Re: [PATCH] ibmvnic: remove excessive irqsave

[Sukadev Bhattiprolu]

angkery [angk...@163.com] wrote:
> From: Junlin Yang 
> 
> ibmvnic_remove locks multiple spinlocks while disabling interrupts:
> spin_lock_irqsave(>state_lock, flags);
> spin_lock_irqsave(>rwi_lock, flags);
> 
> there is no need for the second irqsave,since interrupts are disabled
> at that point, so remove the second irqsave:
> spin_lock_irqsave(>state_lock, flags);
> spin_lock(>rwi_lock);
> 
> Generated by: ./scripts/coccinelle/locks/flags.cocci
> ./drivers/net/ethernet/ibm/ibmvnic.c:5413:1-18:
> ERROR: nested lock+irqsave that reuses flags from line 5404.
> 

Thanks. Please add

Fixes: 4a41c421f367 ("ibmvnic: serialize access to work queue on remove")

> Signed-off-by: Junlin Yang 

Reviewed-by: Sukadev Bhattiprolu 

Re: [PATCH] ibmvnic: Fix possibly uninitialized old_num_tx_queues variable warning.

[Sukadev Bhattiprolu]

Michal Suchanek [msucha...@suse.de] wrote:
> GCC 7.5 reports:
> ../drivers/net/ethernet/ibm/ibmvnic.c: In function 'ibmvnic_reset_init':
> ../drivers/net/ethernet/ibm/ibmvnic.c:5373:51: warning: 'old_num_tx_queues' 
> may be used uninitialized in this function [-Wmaybe-uninitialized]
> ../drivers/net/ethernet/ibm/ibmvnic.c:5373:6: warning: 'old_num_rx_queues' 
> may be used uninitialized in this function [-Wmaybe-uninitialized]
> 
> The variable is initialized only if(reset) and used only if(reset &&
> something) so this is a false positive. However, there is no reason to
> not initialize the variables unconditionally avoiding the warning.

Yeah, its a false positive, but initializing doesn't hurt.
> 
> Fixes: 635e442f4a48 ("ibmvnic: merge ibmvnic_reset_init and ibmvnic_init")
> Signed-off-by: Michal Suchanek 

Reviewed-by: Sukadev Bhattiprolu 

Re: linux-next: manual merge of the net-next tree with the net tree

[Sukadev Bhattiprolu]

Stephen Rothwell [s...@canb.auug.org.au] wrote:
> Hi all,
> 
> Today's linux-next merge of the net-next tree got conflicts in:
> 
>   drivers/net/ethernet/ibm/ibmvnic.c
>   drivers/net/ethernet/ibm/ibmvnic.h
> 
> between commit:
> 
>   4a41c421f367 ("ibmvnic: serialize access to work queue on remove")
> 
> from the net tree and commits:
> 
>   bab08bedcdc3 ("ibmvnic: fix block comments")
>   a369d96ca554 ("ibmvnic: add comments for spinlock_t definitions")
> 
> from the net-next tree.
> 
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging.  You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.

The changes look good to me. Thanks.

Sukadev

Re: [PATCH v2 3/7] powerpc: use task_pid_nr() for TID allocation

[Sukadev Bhattiprolu]

Andrew Donnellan [andrew.donnel...@au1.ibm.com] wrote:
> [+ Sukadev, Christophe]
> 
> On 18/04/18 11:08, Alastair D'Silva wrote:
> > From: Alastair D'Silva 
> > 
> > The current implementation of TID allocation, using a global IDR, may
> > result in an errant process starving the system of available TIDs.
> > Instead, use task_pid_nr(), as mentioned by the original author. The
> > scenario described which prevented it's use is not applicable, as
> > set_thread_tidr can only be called after the task struct has been
> > populated.
> > 
> > Signed-off-by: Alastair D'Silva 
> 
> So it's too late in the evening for me to completely get my head around
> what's going on here enough to give my Reviewed-by:, but my current thinking
> is:
> 
> - In the first version of the patch to add TIDR support
> (https://patchwork.ozlabs.org/patch/799494/), it was originally proposed to
> call assign_thread_id() (as it was then called) from copy_thread()
> 
> - The comment block documents the reason why we can't use task_pid_nr() but
> assumes that we're trying to assign a TIDR from within copy_thread()
> 
> - The final patch that was accepted
> (https://patchwork.ozlabs.org/patch/835552/,
> ec233ede4c8654894610ea54f4dae7adc954ac62) instead sets the TIDR to 0 from
> copy_thread(), so the original reasoning regarding not using task_pid_nr()
> within copy_thread() is no longer applicable.
> 
> Sukadev: does this sound right?

Yes. Like with PIDR, was trying to assign TIDR initially to all threads.
But since only a subset of threads need/use TIDR, we can assign the
value later (when set_thread_tidr() is called). So we should be able to
use task_pid_nr() then.

Sukadev

Re: [PATCH v2 3/7] powerpc: use task_pid_nr() for TID allocation

[Sukadev Bhattiprolu]

Andrew Donnellan [andrew.donnel...@au1.ibm.com] wrote:
> [+ Sukadev, Christophe]
> 
> On 18/04/18 11:08, Alastair D'Silva wrote:
> > From: Alastair D'Silva 
> > 
> > The current implementation of TID allocation, using a global IDR, may
> > result in an errant process starving the system of available TIDs.
> > Instead, use task_pid_nr(), as mentioned by the original author. The
> > scenario described which prevented it's use is not applicable, as
> > set_thread_tidr can only be called after the task struct has been
> > populated.
> > 
> > Signed-off-by: Alastair D'Silva 
> 
> So it's too late in the evening for me to completely get my head around
> what's going on here enough to give my Reviewed-by:, but my current thinking
> is:
> 
> - In the first version of the patch to add TIDR support
> (https://patchwork.ozlabs.org/patch/799494/), it was originally proposed to
> call assign_thread_id() (as it was then called) from copy_thread()
> 
> - The comment block documents the reason why we can't use task_pid_nr() but
> assumes that we're trying to assign a TIDR from within copy_thread()
> 
> - The final patch that was accepted
> (https://patchwork.ozlabs.org/patch/835552/,
> ec233ede4c8654894610ea54f4dae7adc954ac62) instead sets the TIDR to 0 from
> copy_thread(), so the original reasoning regarding not using task_pid_nr()
> within copy_thread() is no longer applicable.
> 
> Sukadev: does this sound right?

Yes. Like with PIDR, was trying to assign TIDR initially to all threads.
But since only a subset of threads need/use TIDR, we can assign the
value later (when set_thread_tidr() is called). So we should be able to
use task_pid_nr() then.

Sukadev

[tip:perf/core] perf vendor events: Update POWER9 events

[tip-bot for Sukadev Bhattiprolu]

Commit-ID:  9749adc3b2a23c91b2eda8758ff0c650d731aa2f
Gitweb: https://git.kernel.org/tip/9749adc3b2a23c91b2eda8758ff0c650d731aa2f
Author: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
AuthorDate: Tue, 13 Mar 2018 12:33:29 -0500
Committer:  Arnaldo Carvalho de Melo <a...@redhat.com>
CommitDate: Fri, 16 Mar 2018 13:57:08 -0300

perf vendor events: Update POWER9 events

Cc: linuxppc-...@lists.ozlabs.org
Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20180313224647.ga22...@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com>
---
 .../perf/pmu-events/arch/powerpc/power9/cache.json |  25 ---
 .../pmu-events/arch/powerpc/power9/frontend.json   |  10 -
 .../pmu-events/arch/powerpc/power9/marked.json |   5 -
 .../pmu-events/arch/powerpc/power9/memory.json |   5 -
 .../perf/pmu-events/arch/powerpc/power9/other.json | 241 ++---
 .../pmu-events/arch/powerpc/power9/pipeline.json   |  50 ++---
 tools/perf/pmu-events/arch/powerpc/power9/pmc.json |   5 -
 .../arch/powerpc/power9/translation.json   |  10 +-
 8 files changed, 178 insertions(+), 173 deletions(-)

diff --git a/tools/perf/pmu-events/arch/powerpc/power9/cache.json 
b/tools/perf/pmu-events/arch/powerpc/power9/cache.json
index 7945c5196c43..851072105054 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/cache.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/cache.json
@@ -19,11 +19,6 @@
 "EventName": "PM_CMPLU_STALL_FXU",
 "BriefDescription": "Finish stall due to a scalar fixed point or CR 
instruction in the execution pipeline. These instructions get routed to the 
ALU, ALU2, and DIV pipes"
   },
-  {,
-"EventCode": "0x1D15C",
-"EventName": "PM_MRK_DTLB_MISS_1G",
-"BriefDescription": "Marked Data TLB reload (after a miss) page size 2M. 
Implies radix translation was used"
-  },
   {,
 "EventCode": "0x4D12A",
 "EventName": "PM_MRK_DATA_FROM_RL4_CYC",
@@ -79,21 +74,6 @@
 "EventName": "PM_THRESH_EXC_4096",
 "BriefDescription": "Threshold counter exceed a count of 4096"
   },
-  {,
-"EventCode": "0x3D156",
-"EventName": "PM_MRK_DTLB_MISS_64K",
-"BriefDescription": "Marked Data TLB Miss page size 64K"
-  },
-  {,
-"EventCode": "0x4C15E",
-"EventName": "PM_MRK_DTLB_MISS_16M",
-"BriefDescription": "Marked Data TLB Miss page size 16M"
-  },
-  {,
-"EventCode": "0x2D15E",
-"EventName": "PM_MRK_DTLB_MISS_16G",
-"BriefDescription": "Marked Data TLB Miss page size 16G"
-  },
   {,
 "EventCode": "0x3F14A",
 "EventName": "PM_MRK_DPTEG_FROM_RMEM",
@@ -123,10 +103,5 @@
 "EventCode": "0x1002A",
 "EventName": "PM_CMPLU_STALL_LARX",
 "BriefDescription": "Finish stall because the NTF instruction was a larx 
waiting to be satisfied"
-  },
-  {,
-"EventCode": "0x1C058",
-"EventName": "PM_DTLB_MISS_16G",
-"BriefDescription": "Data TLB Miss page size 16G"
   }
 ]
\ No newline at end of file
diff --git a/tools/perf/pmu-events/arch/powerpc/power9/frontend.json 
b/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
index bd8361b5fd6a..f9fa84b16fb5 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
@@ -154,11 +154,6 @@
 "EventName": "PM_MRK_DATA_FROM_RL2L3_SHR_CYC",
 "BriefDescription": "Duration in cycles to reload with Shared (S) data 
from another chip's L2 or L3 on the same Node or Group (Remote), as this chip 
due to a marked load"
   },
-  {,
-"EventCode": "0x3C056",
-"EventName": "PM_DTLB_MISS_64K",
-"BriefDescription": "Data TLB Miss page size 64K"
-  },
   {,
 "EventCode": "0x30060",
 "EventName": "PM_TM_TRANS_RUN_INST",
@@ -344,11 +339,6 @@
 "EventName": "PM_MRK_LARX_FIN",
 "BriefDescription": "Larx finished"
   },
-  {,
-"EventCode": "0x4C056",
-"EventName": "PM_DTLB_MISS_16M",
-"BriefDescription": "Data TLB Miss page size 16M"
-  },
   {,
 "EventCode": "0x1003A",
 "EventName": "PM_CMPLU_STALL_LSU_FIN",
diff --git a/tools/perf/pmu-events/arch/powerpc/power9/marked.json 
b/tools/perf/pmu-events/arch/powerpc/power9/mar

[tip:perf/core] perf vendor events: Update POWER9 events

[tip-bot for Sukadev Bhattiprolu]

Commit-ID:  9749adc3b2a23c91b2eda8758ff0c650d731aa2f
Gitweb: https://git.kernel.org/tip/9749adc3b2a23c91b2eda8758ff0c650d731aa2f
Author: Sukadev Bhattiprolu 
AuthorDate: Tue, 13 Mar 2018 12:33:29 -0500
Committer:  Arnaldo Carvalho de Melo 
CommitDate: Fri, 16 Mar 2018 13:57:08 -0300

perf vendor events: Update POWER9 events

Cc: linuxppc-...@lists.ozlabs.org
Signed-off-by: Sukadev Bhattiprolu 
Link: https://lkml.kernel.org/r/20180313224647.ga22...@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo 
---
 .../perf/pmu-events/arch/powerpc/power9/cache.json |  25 ---
 .../pmu-events/arch/powerpc/power9/frontend.json   |  10 -
 .../pmu-events/arch/powerpc/power9/marked.json |   5 -
 .../pmu-events/arch/powerpc/power9/memory.json |   5 -
 .../perf/pmu-events/arch/powerpc/power9/other.json | 241 ++---
 .../pmu-events/arch/powerpc/power9/pipeline.json   |  50 ++---
 tools/perf/pmu-events/arch/powerpc/power9/pmc.json |   5 -
 .../arch/powerpc/power9/translation.json   |  10 +-
 8 files changed, 178 insertions(+), 173 deletions(-)

diff --git a/tools/perf/pmu-events/arch/powerpc/power9/cache.json 
b/tools/perf/pmu-events/arch/powerpc/power9/cache.json
index 7945c5196c43..851072105054 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/cache.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/cache.json
@@ -19,11 +19,6 @@
 "EventName": "PM_CMPLU_STALL_FXU",
 "BriefDescription": "Finish stall due to a scalar fixed point or CR 
instruction in the execution pipeline. These instructions get routed to the 
ALU, ALU2, and DIV pipes"
   },
-  {,
-"EventCode": "0x1D15C",
-"EventName": "PM_MRK_DTLB_MISS_1G",
-"BriefDescription": "Marked Data TLB reload (after a miss) page size 2M. 
Implies radix translation was used"
-  },
   {,
 "EventCode": "0x4D12A",
 "EventName": "PM_MRK_DATA_FROM_RL4_CYC",
@@ -79,21 +74,6 @@
 "EventName": "PM_THRESH_EXC_4096",
 "BriefDescription": "Threshold counter exceed a count of 4096"
   },
-  {,
-"EventCode": "0x3D156",
-"EventName": "PM_MRK_DTLB_MISS_64K",
-"BriefDescription": "Marked Data TLB Miss page size 64K"
-  },
-  {,
-"EventCode": "0x4C15E",
-"EventName": "PM_MRK_DTLB_MISS_16M",
-"BriefDescription": "Marked Data TLB Miss page size 16M"
-  },
-  {,
-"EventCode": "0x2D15E",
-"EventName": "PM_MRK_DTLB_MISS_16G",
-"BriefDescription": "Marked Data TLB Miss page size 16G"
-  },
   {,
 "EventCode": "0x3F14A",
 "EventName": "PM_MRK_DPTEG_FROM_RMEM",
@@ -123,10 +103,5 @@
 "EventCode": "0x1002A",
 "EventName": "PM_CMPLU_STALL_LARX",
 "BriefDescription": "Finish stall because the NTF instruction was a larx 
waiting to be satisfied"
-  },
-  {,
-"EventCode": "0x1C058",
-"EventName": "PM_DTLB_MISS_16G",
-"BriefDescription": "Data TLB Miss page size 16G"
   }
 ]
\ No newline at end of file
diff --git a/tools/perf/pmu-events/arch/powerpc/power9/frontend.json 
b/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
index bd8361b5fd6a..f9fa84b16fb5 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
@@ -154,11 +154,6 @@
 "EventName": "PM_MRK_DATA_FROM_RL2L3_SHR_CYC",
 "BriefDescription": "Duration in cycles to reload with Shared (S) data 
from another chip's L2 or L3 on the same Node or Group (Remote), as this chip 
due to a marked load"
   },
-  {,
-"EventCode": "0x3C056",
-"EventName": "PM_DTLB_MISS_64K",
-"BriefDescription": "Data TLB Miss page size 64K"
-  },
   {,
 "EventCode": "0x30060",
 "EventName": "PM_TM_TRANS_RUN_INST",
@@ -344,11 +339,6 @@
 "EventName": "PM_MRK_LARX_FIN",
 "BriefDescription": "Larx finished"
   },
-  {,
-"EventCode": "0x4C056",
-"EventName": "PM_DTLB_MISS_16M",
-"BriefDescription": "Data TLB Miss page size 16M"
-  },
   {,
 "EventCode": "0x1003A",
 "EventName": "PM_CMPLU_STALL_LSU_FIN",
diff --git a/tools/perf/pmu-events/arch/powerpc/power9/marked.json 
b/tools/perf/pmu-events/arch/powerpc/power9/marked.json
index 22f9f32060a8..b1954c38bab1 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/marked.json
+++

Re: [PATCH] perf vendor events: fix processing for xfs

[Sukadev Bhattiprolu]

John Garry [john.ga...@huawei.com] wrote:
> In the recently introduced support for vendor subdirectory,
> the checking for directory entries under xfs (or any other fs
> which does not support dirent.d_type) is missing the check
> for links for current and parent directory. This can result
> in a broken pmu_events.c being generated.

I run into the problem on a 4.15-based kernel/xfs but not on a
3.10-based kernel! Have not investigated, but this fix is good.
> 
> Fix this by adding the appropriate check in is_leaf_dir().
> 
> Cc: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
> Signed-off-by: John Garry <john.ga...@huawei.com>

Tested-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>

Thanks John.

Sukadev
> 
> diff --git a/tools/perf/pmu-events/jevents.c b/tools/perf/pmu-events/jevents.c
> index 1c01844..db3a594 100644
> --- a/tools/perf/pmu-events/jevents.c
> +++ b/tools/perf/pmu-events/jevents.c
> @@ -873,7 +873,10 @@ static int is_leaf_dir(const char *fpath)
>   return 0;
> 
>   while ((dir = readdir(d)) != NULL) {
> - if (dir->d_type == DT_DIR && dir->d_name[0] != '.') {
> + if (!strcmp(dir->d_name, ".") || !strcmp(dir->d_name, ".."))
> + continue;
> +
> + if (dir->d_type == DT_DIR) {
>   res = 0;
>   break;
>   } else if (dir->d_type == DT_UNKNOWN) {
> -- 
> 1.9.1

Re: [PATCH] perf vendor events: fix processing for xfs

[Sukadev Bhattiprolu]

John Garry [john.ga...@huawei.com] wrote:
> In the recently introduced support for vendor subdirectory,
> the checking for directory entries under xfs (or any other fs
> which does not support dirent.d_type) is missing the check
> for links for current and parent directory. This can result
> in a broken pmu_events.c being generated.

I run into the problem on a 4.15-based kernel/xfs but not on a
3.10-based kernel! Have not investigated, but this fix is good.
> 
> Fix this by adding the appropriate check in is_leaf_dir().
> 
> Cc: Sukadev Bhattiprolu 
> Signed-off-by: John Garry 

Tested-by: Sukadev Bhattiprolu 

Thanks John.

Sukadev
> 
> diff --git a/tools/perf/pmu-events/jevents.c b/tools/perf/pmu-events/jevents.c
> index 1c01844..db3a594 100644
> --- a/tools/perf/pmu-events/jevents.c
> +++ b/tools/perf/pmu-events/jevents.c
> @@ -873,7 +873,10 @@ static int is_leaf_dir(const char *fpath)
>   return 0;
> 
>   while ((dir = readdir(d)) != NULL) {
> - if (dir->d_type == DT_DIR && dir->d_name[0] != '.') {
> + if (!strcmp(dir->d_name, ".") || !strcmp(dir->d_name, ".."))
> + continue;
> +
> + if (dir->d_type == DT_DIR) {
>   res = 0;
>   break;
>   } else if (dir->d_type == DT_UNKNOWN) {
> -- 
> 1.9.1

[GIT PULL] Please pull JSON files for POWR9 PMU events

[Sukadev Bhattiprolu]

Hi Arnaldo,

Please pull an update to the JSON files for POWER9 PMU events.

The following changes since commit 90d2614c4d10c2f9d0ada9a3b01e5f43ca8d1ae3:

  perf test: Fix exit code for record+probe_libc_inet_pton.sh (2018-03-13 
15:14:43 -0300)

are available in the git repository at:

  https://github.com/sukadev/linux/ p9-json-v5

for you to fetch changes up to 99c9dff949f2502964005f9afa8d60c89b446f2c:

  perf vendor events: Update POWER9 events (2018-03-13 16:48:12 -0500)


Sukadev Bhattiprolu (1):
  perf vendor events: Update POWER9 events

 .../perf/pmu-events/arch/powerpc/power9/cache.json |  25 ---
 .../pmu-events/arch/powerpc/power9/frontend.json   |  10 -
 .../pmu-events/arch/powerpc/power9/marked.json |   5 -
 .../pmu-events/arch/powerpc/power9/memory.json |   5 -
 .../perf/pmu-events/arch/powerpc/power9/other.json | 241 ++---
 .../pmu-events/arch/powerpc/power9/pipeline.json   |  50 ++---
 tools/perf/pmu-events/arch/powerpc/power9/pmc.json |   5 -
 .../arch/powerpc/power9/translation.json   |  10 +-
 8 files changed, 178 insertions(+), 173 deletions(-)

[GIT PULL] Please pull JSON files for POWR9 PMU events

[Sukadev Bhattiprolu]

Hi Arnaldo,

Please pull an update to the JSON files for POWER9 PMU events.

The following changes since commit 90d2614c4d10c2f9d0ada9a3b01e5f43ca8d1ae3:

  perf test: Fix exit code for record+probe_libc_inet_pton.sh (2018-03-13 
15:14:43 -0300)

are available in the git repository at:

  https://github.com/sukadev/linux/ p9-json-v5

for you to fetch changes up to 99c9dff949f2502964005f9afa8d60c89b446f2c:

  perf vendor events: Update POWER9 events (2018-03-13 16:48:12 -0500)


Sukadev Bhattiprolu (1):
  perf vendor events: Update POWER9 events

 .../perf/pmu-events/arch/powerpc/power9/cache.json |  25 ---
 .../pmu-events/arch/powerpc/power9/frontend.json   |  10 -
 .../pmu-events/arch/powerpc/power9/marked.json |   5 -
 .../pmu-events/arch/powerpc/power9/memory.json |   5 -
 .../perf/pmu-events/arch/powerpc/power9/other.json | 241 ++---
 .../pmu-events/arch/powerpc/power9/pipeline.json   |  50 ++---
 tools/perf/pmu-events/arch/powerpc/power9/pmc.json |   5 -
 .../arch/powerpc/power9/translation.json   |  10 +-
 8 files changed, 178 insertions(+), 173 deletions(-)

Re: perf-core build fails on powerpc

[Sukadev Bhattiprolu]

John Garry [john.ga...@huawei.com] wrote:
> On 13/03/2018 20:10, Sukadev Bhattiprolu wrote:
> 
> > Hi John,
> > 
> > I have an xfs file system which seems to have d_type == DT_UNKNOWN for all
> > entries in 'tools/perf/pmu-events/arch/power8'! readdir(3) says ->d_type
> > may not be supported by all file systems.
> > 
> > Not relying on ->d_type seems to fix it:
> > 
> 
> Hi Sukadev,
> 
> Thanks for debugging this. Jiri Olsa (cc'ed) warned me on this, so I did add
> the check for d_type == DT_UNKNOWN.
> 
> But, if all files have d_type == DT_UNKNOWN, you're code would from visual
> observation look to be same as mine (apart from check for '.' or '..'
> filename, which I would say is already covered by stat() and S_ISDIR()). Or
> is d_type value just unreliable?

In the current code and with DT_UNKNOWN, is_leaf_dir() returns false when
it sees the "." or ".." entries right? In the new code, we skip those and
return false only if we find some other directory. 

Thanks,

Sukadev

Re: perf-core build fails on powerpc

[Sukadev Bhattiprolu]

John Garry [john.ga...@huawei.com] wrote:
> On 13/03/2018 20:10, Sukadev Bhattiprolu wrote:
> 
> > Hi John,
> > 
> > I have an xfs file system which seems to have d_type == DT_UNKNOWN for all
> > entries in 'tools/perf/pmu-events/arch/power8'! readdir(3) says ->d_type
> > may not be supported by all file systems.
> > 
> > Not relying on ->d_type seems to fix it:
> > 
> 
> Hi Sukadev,
> 
> Thanks for debugging this. Jiri Olsa (cc'ed) warned me on this, so I did add
> the check for d_type == DT_UNKNOWN.
> 
> But, if all files have d_type == DT_UNKNOWN, you're code would from visual
> observation look to be same as mine (apart from check for '.' or '..'
> filename, which I would say is already covered by stat() and S_ISDIR()). Or
> is d_type value just unreliable?

In the current code and with DT_UNKNOWN, is_leaf_dir() returns false when
it sees the "." or ".." entries right? In the new code, we skip those and
return false only if we find some other directory. 

Thanks,

Sukadev

Re: perf-core build fails on powerpc

[Sukadev Bhattiprolu]

John Garry [john.ga...@huawei.com] wrote:
> On 13/03/2018 19:17, Sukadev Bhattiprolu wrote:
> > 
> > 
> > Building perf on Powerpc seems broken when using Arnaldo's perf/core branch
> > with HEAD as:
> > 
> > 1b442ed ("perf test: Fix exit code for record+probe_libc_inet_pton.sh")
> > 
> > It maybe related to this commit:
> > 
> > commit d596299
> > Author: John Garry <john.ga...@huawei.com>
> > Date:   Thu Mar 8 18:58:29 2018 +0800
> > 
> > perf vendor events: Add support for pmu events vendor subdirectory
> > 
> > Reverting this hunk from tools/perf/pmu-events/jevents.c, seems to fix the
> > problem for me.
> > 

Hi John,

I have an xfs file system which seems to have d_type == DT_UNKNOWN for all
entries in 'tools/perf/pmu-events/arch/power8'! readdir(3) says ->d_type
may not be supported by all file systems.

Not relying on ->d_type seems to fix it:

@@ -873,26 +879,26 @@ static int is_leaf_dir(const char *fpath)
return 0;
 
while ((dir = readdir(d)) != NULL) {
-   if (dir->d_type == DT_DIR && dir->d_name[0] != '.') {
-   res = 0;
-   break;
-   } else if (dir->d_type == DT_UNKNOWN) {
-   char path[PATH_MAX];
-   struct stat st;
+   char path[PATH_MAX];
+   struct stat st;
 
-   sprintf(path, "%s/%s", fpath, dir->d_name);
-   if (stat(path, ))
-   break;
+   if (strcmp(dir->d_name, ".") == 0 ||
+   strcmp(dir->d_name, "..") == 0)
+   continue;
 
-   if (S_ISDIR(st.st_mode)) {
-   res = 0;
-   break;
-   }
+   sprintf(path, "%s/%s", fpath, dir->d_name);
+   if (stat(path, ))
+   break;
+
+   if (S_ISDIR(st.st_mode)) {
+   res = 0;
+   break;

Re: perf-core build fails on powerpc

[Sukadev Bhattiprolu]

John Garry [john.ga...@huawei.com] wrote:
> On 13/03/2018 19:17, Sukadev Bhattiprolu wrote:
> > 
> > 
> > Building perf on Powerpc seems broken when using Arnaldo's perf/core branch
> > with HEAD as:
> > 
> > 1b442ed ("perf test: Fix exit code for record+probe_libc_inet_pton.sh")
> > 
> > It maybe related to this commit:
> > 
> > commit d596299
> > Author: John Garry 
> > Date:   Thu Mar 8 18:58:29 2018 +0800
> > 
> > perf vendor events: Add support for pmu events vendor subdirectory
> > 
> > Reverting this hunk from tools/perf/pmu-events/jevents.c, seems to fix the
> > problem for me.
> > 

Hi John,

I have an xfs file system which seems to have d_type == DT_UNKNOWN for all
entries in 'tools/perf/pmu-events/arch/power8'! readdir(3) says ->d_type
may not be supported by all file systems.

Not relying on ->d_type seems to fix it:

@@ -873,26 +879,26 @@ static int is_leaf_dir(const char *fpath)
return 0;
 
while ((dir = readdir(d)) != NULL) {
-   if (dir->d_type == DT_DIR && dir->d_name[0] != '.') {
-   res = 0;
-   break;
-   } else if (dir->d_type == DT_UNKNOWN) {
-   char path[PATH_MAX];
-   struct stat st;
+   char path[PATH_MAX];
+   struct stat st;
 
-   sprintf(path, "%s/%s", fpath, dir->d_name);
-   if (stat(path, ))
-   break;
+   if (strcmp(dir->d_name, ".") == 0 ||
+   strcmp(dir->d_name, "..") == 0)
+   continue;
 
-   if (S_ISDIR(st.st_mode)) {
-   res = 0;
-   break;
-   }
+   sprintf(path, "%s/%s", fpath, dir->d_name);
+   if (stat(path, ))
+   break;
+
+   if (S_ISDIR(st.st_mode)) {
+   res = 0;
+   break;

perf-core build fails on powerpc

[Sukadev Bhattiprolu]

Building perf on Powerpc seems broken when using Arnaldo's perf/core branch
with HEAD as:

1b442ed ("perf test: Fix exit code for record+probe_libc_inet_pton.sh")

It maybe related to this commit:

commit d596299
Author: John Garry 
Date:   Thu Mar 8 18:58:29 2018 +0800

perf vendor events: Add support for pmu events vendor subdirectory

Reverting this hunk from tools/perf/pmu-events/jevents.c, seems to fix the
problem for me.

@@ -957,8 +963,12 @@ static int process_one_file(const char *fpath, const struct
 
 
/* model directory, reset topic */
+#if 0
if ((level == 1 && is_dir && is_leaf_dir(fpath)) ||
(level == 2 && is_dir)) {
+#else
+   if (level == 1 && is_dir) {
+#endif


The problem is that the tools/perf/pmu-events/pmu-events.c file generated by
the jevents program is missing the "prefix" lines like:

struct pmu_event pme_power8[] = {
and 
struct pmu_event pme_power9[] = {


i.e the pmu-events.c begins like:
---

#include "../../pmu-events/pmu-events.h"
{
.name = "pm_data_from_dl2l3_mod",
.event = "event=0x4c048",
.desc = "The processor's data cache was reloaded with Modified (M) data 
from another chip's L2 or L3 on a different Node or Group (Distant), as this 
chip due to a demand load",
.topic = "cache",
.long_desc = "The processor's data cache was reloaded with Modified (M) 
data from another chip's L2 or L3 on a different Node or Group (Distant), as 
this chip due to either only demand loads or demand loads plus prefetches if 
MMCR1[16] is 1",
},

---

Below is the debug and info messages at the time of failure:

---

  HOSTCC   /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/jevents.o
  HOSTLD   /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/jevents-in.o
  LINK /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/jevents
  GEN  /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c
d 0  50 powerpc  pmu-events/arch/powerpc
d 14096 power8   pmu-events/arch/powerpc/power8
f 2   10275 cache.json   pmu-events/arch/powerpc/power8/cache.json
f 2 302 floating-point.json  
pmu-events/arch/powerpc/power8/floating-point.json
f 2   29283 marked.json  pmu-events/arch/powerpc/power8/marked.json
f 2   12028 memory.json  pmu-events/arch/powerpc/power8/memory.json
f 2  159271 other.json   pmu-events/arch/powerpc/power8/other.json
f 2   10777 pipeline.jsonpmu-events/arch/powerpc/power8/pipeline.json
f 23781 pmc.json pmu-events/arch/powerpc/power8/pmc.json
f 26664 translation.json pmu-events/arch/powerpc/power8/translation.json
f 2   25104 frontend.jsonpmu-events/arch/powerpc/power8/frontend.json
d 14096 power9   pmu-events/arch/powerpc/power9
f 21096 floating-point.json  
pmu-events/arch/powerpc/power9/floating-point.json
f 25503 cache.json   pmu-events/arch/powerpc/power9/cache.json
f 2   14885 frontend.jsonpmu-events/arch/powerpc/power9/frontend.json
f 2   27807 marked.json  pmu-events/arch/powerpc/power9/marked.json
f 24820 memory.json  pmu-events/arch/powerpc/power9/memory.json
f 2   85387 other.json   pmu-events/arch/powerpc/power9/other.json
f 2   23839 pipeline.jsonpmu-events/arch/powerpc/power9/pipeline.json
f 25138 pmc.json pmu-events/arch/powerpc/power9/pmc.json
f 29897 translation.json pmu-events/arch/powerpc/power9/translation.json
f 1 440 mapfile.csv  pmu-events/arch/powerpc/mapfile.csv
jevents: Processing mapfile pmu-events/arch/powerpc/mapfile.csv
  CC   /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.o
/home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c:2:1: 
error: expected identifier or ‘(’ before ‘{’ token
 {
 ^
/home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c:8:2: 
error: expected identifier or ‘(’ before ‘,’ token
 },
  ^
/home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c:15:2: 
error: expected identifier or ‘(’ before ‘,’ token
 },
  ^
/home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c:22:2: 
error: expected identifier or ‘(’ before ‘,’ token
 },

perf-core build fails on powerpc

[Sukadev Bhattiprolu]

Building perf on Powerpc seems broken when using Arnaldo's perf/core branch
with HEAD as:

1b442ed ("perf test: Fix exit code for record+probe_libc_inet_pton.sh")

It maybe related to this commit:

commit d596299
Author: John Garry 
Date:   Thu Mar 8 18:58:29 2018 +0800

perf vendor events: Add support for pmu events vendor subdirectory

Reverting this hunk from tools/perf/pmu-events/jevents.c, seems to fix the
problem for me.

@@ -957,8 +963,12 @@ static int process_one_file(const char *fpath, const struct
 
 
/* model directory, reset topic */
+#if 0
if ((level == 1 && is_dir && is_leaf_dir(fpath)) ||
(level == 2 && is_dir)) {
+#else
+   if (level == 1 && is_dir) {
+#endif


The problem is that the tools/perf/pmu-events/pmu-events.c file generated by
the jevents program is missing the "prefix" lines like:

struct pmu_event pme_power8[] = {
and 
struct pmu_event pme_power9[] = {


i.e the pmu-events.c begins like:
---

#include "../../pmu-events/pmu-events.h"
{
.name = "pm_data_from_dl2l3_mod",
.event = "event=0x4c048",
.desc = "The processor's data cache was reloaded with Modified (M) data 
from another chip's L2 or L3 on a different Node or Group (Distant), as this 
chip due to a demand load",
.topic = "cache",
.long_desc = "The processor's data cache was reloaded with Modified (M) 
data from another chip's L2 or L3 on a different Node or Group (Distant), as 
this chip due to either only demand loads or demand loads plus prefetches if 
MMCR1[16] is 1",
},

---

Below is the debug and info messages at the time of failure:

---

  HOSTCC   /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/jevents.o
  HOSTLD   /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/jevents-in.o
  LINK /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/jevents
  GEN  /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c
d 0  50 powerpc  pmu-events/arch/powerpc
d 14096 power8   pmu-events/arch/powerpc/power8
f 2   10275 cache.json   pmu-events/arch/powerpc/power8/cache.json
f 2 302 floating-point.json  
pmu-events/arch/powerpc/power8/floating-point.json
f 2   29283 marked.json  pmu-events/arch/powerpc/power8/marked.json
f 2   12028 memory.json  pmu-events/arch/powerpc/power8/memory.json
f 2  159271 other.json   pmu-events/arch/powerpc/power8/other.json
f 2   10777 pipeline.jsonpmu-events/arch/powerpc/power8/pipeline.json
f 23781 pmc.json pmu-events/arch/powerpc/power8/pmc.json
f 26664 translation.json pmu-events/arch/powerpc/power8/translation.json
f 2   25104 frontend.jsonpmu-events/arch/powerpc/power8/frontend.json
d 14096 power9   pmu-events/arch/powerpc/power9
f 21096 floating-point.json  
pmu-events/arch/powerpc/power9/floating-point.json
f 25503 cache.json   pmu-events/arch/powerpc/power9/cache.json
f 2   14885 frontend.jsonpmu-events/arch/powerpc/power9/frontend.json
f 2   27807 marked.json  pmu-events/arch/powerpc/power9/marked.json
f 24820 memory.json  pmu-events/arch/powerpc/power9/memory.json
f 2   85387 other.json   pmu-events/arch/powerpc/power9/other.json
f 2   23839 pipeline.jsonpmu-events/arch/powerpc/power9/pipeline.json
f 25138 pmc.json pmu-events/arch/powerpc/power9/pmc.json
f 29897 translation.json pmu-events/arch/powerpc/power9/translation.json
f 1 440 mapfile.csv  pmu-events/arch/powerpc/mapfile.csv
jevents: Processing mapfile pmu-events/arch/powerpc/mapfile.csv
  CC   /home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.o
/home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c:2:1: 
error: expected identifier or ‘(’ before ‘{’ token
 {
 ^
/home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c:8:2: 
error: expected identifier or ‘(’ before ‘,’ token
 },
  ^
/home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c:15:2: 
error: expected identifier or ‘(’ before ‘,’ token
 },
  ^
/home/suka/linux-acme.git/tools/perf/perf-obj/pmu-events/pmu-events.c:22:2: 
error: expected identifier or ‘(’ before ‘,’ token
 },

[PATCH] Fix cleanup when VAS is not configured

[Sukadev Bhattiprolu]

From: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Date: Fri, 9 Feb 2018 11:49:06 -0600
Subject: [PATCH 1/1] powerpc/vas: Fix cleanup when VAS is not configured

When VAS is not configured, unregister the platform driver. Also simplify
cleanup by delaying vas debugfs init until we know VAS is configured.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v2]
- [Michael Ellerman] Move vas_init_dbgdir() into a lower level
  function to keep vas_init() cleaner.
---
 arch/powerpc/platforms/powernv/vas-debug.c | 11 +++
 arch/powerpc/platforms/powernv/vas.c   |  6 +++---
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
index b4de4c6..4f7276e 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -179,6 +179,7 @@ void vas_instance_init_dbgdir(struct vas_instance *vinst)
 {
struct dentry *d;
 
+   vas_init_dbgdir();
if (!vas_debugfs)
return;
 
@@ -201,8 +202,18 @@ void vas_instance_init_dbgdir(struct vas_instance *vinst)
vinst->dbgdir = NULL;
 }
 
+/*
+ * Set up the "root" VAS debugfs dir. Return if we already set it up
+ * (or failed to) in an earlier instance of VAS.
+ */
 void vas_init_dbgdir(void)
 {
+   static bool first_time = true;
+
+   if (!first_time)
+   return;
+
+   first_time = false;
vas_debugfs = debugfs_create_dir("vas", NULL);
if (IS_ERR(vas_debugfs))
vas_debugfs = NULL;
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index aebbe95..5a2b24c 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -160,8 +160,6 @@ static int __init vas_init(void)
int found = 0;
struct device_node *dn;
 
-   vas_init_dbgdir();
-
platform_driver_register(_driver);
 
for_each_compatible_node(dn, NULL, "ibm,vas") {
@@ -169,8 +167,10 @@ static int __init vas_init(void)
found++;
}
 
-   if (!found)
+   if (!found) {
+   platform_driver_unregister(_driver);
return -ENODEV;
+   }
 
pr_devel("Found %d instances\n", found);
 
-- 
2.7.4

[PATCH] Fix cleanup when VAS is not configured

[Sukadev Bhattiprolu]

From: Sukadev Bhattiprolu 
Date: Fri, 9 Feb 2018 11:49:06 -0600
Subject: [PATCH 1/1] powerpc/vas: Fix cleanup when VAS is not configured

When VAS is not configured, unregister the platform driver. Also simplify
cleanup by delaying vas debugfs init until we know VAS is configured.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v2]
- [Michael Ellerman] Move vas_init_dbgdir() into a lower level
  function to keep vas_init() cleaner.
---
 arch/powerpc/platforms/powernv/vas-debug.c | 11 +++
 arch/powerpc/platforms/powernv/vas.c   |  6 +++---
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
index b4de4c6..4f7276e 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -179,6 +179,7 @@ void vas_instance_init_dbgdir(struct vas_instance *vinst)
 {
struct dentry *d;
 
+   vas_init_dbgdir();
if (!vas_debugfs)
return;
 
@@ -201,8 +202,18 @@ void vas_instance_init_dbgdir(struct vas_instance *vinst)
vinst->dbgdir = NULL;
 }
 
+/*
+ * Set up the "root" VAS debugfs dir. Return if we already set it up
+ * (or failed to) in an earlier instance of VAS.
+ */
 void vas_init_dbgdir(void)
 {
+   static bool first_time = true;
+
+   if (!first_time)
+   return;
+
+   first_time = false;
vas_debugfs = debugfs_create_dir("vas", NULL);
if (IS_ERR(vas_debugfs))
vas_debugfs = NULL;
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index aebbe95..5a2b24c 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -160,8 +160,6 @@ static int __init vas_init(void)
int found = 0;
struct device_node *dn;
 
-   vas_init_dbgdir();
-
platform_driver_register(_driver);
 
for_each_compatible_node(dn, NULL, "ibm,vas") {
@@ -169,8 +167,10 @@ static int __init vas_init(void)
found++;
}
 
-   if (!found)
+   if (!found) {
+   platform_driver_unregister(_driver);
return -ENODEV;
+   }
 
pr_devel("Found %d instances\n", found);
 
-- 
2.7.4

Re: [PATCH 2/4] powerpc/vas: Fix cleanup when VAS is not configured

[Sukadev Bhattiprolu]

Michael Ellerman [m...@ellerman.id.au] wrote:
> Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com> writes:
> 
> > When VAS is not configured in the system, make sure to remove
> > the VAS debugfs directory and unregister the platform driver.
> >
> > Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
> ...
> > diff --git a/arch/powerpc/platforms/powernv/vas.c 
> > b/arch/powerpc/platforms/powernv/vas.c
> > index aebbe95..f83e27d8 100644
> > --- a/arch/powerpc/platforms/powernv/vas.c
> > +++ b/arch/powerpc/platforms/powernv/vas.c
> > @@ -169,8 +169,11 @@ static int __init vas_init(void)
> > found++;
> > }
> >  
> > -   if (!found)
> > +   if (!found) {
> > +   platform_driver_unregister(_driver);
> > +   vas_cleanup_dbgdir();
> > return -ENODEV;
> > +   }
> 
> The better patch would be to move the call to vas_init_dbgdir() down
> here, where we know we have successfully registered the driver.

Well, when VAS is configured, init_vas_instance() expects the top level
"vas" debugfs dir to already be setup.

We could have each init_vas_instance() assume it is the first and
unconditionally call vas_init_dbgdir(). vas_init_dbgdir() could make
sure to initialize only once.

Or, we could make a separate pass countng "ibm,vas" nodes. If there are
none, skip both steps (dbgdir and registering platform driver).

Sukadev

Re: [PATCH 2/4] powerpc/vas: Fix cleanup when VAS is not configured

[Sukadev Bhattiprolu]

Michael Ellerman [m...@ellerman.id.au] wrote:
> Sukadev Bhattiprolu  writes:
> 
> > When VAS is not configured in the system, make sure to remove
> > the VAS debugfs directory and unregister the platform driver.
> >
> > Signed-off-by: Sukadev Bhattiprolu 
> ...
> > diff --git a/arch/powerpc/platforms/powernv/vas.c 
> > b/arch/powerpc/platforms/powernv/vas.c
> > index aebbe95..f83e27d8 100644
> > --- a/arch/powerpc/platforms/powernv/vas.c
> > +++ b/arch/powerpc/platforms/powernv/vas.c
> > @@ -169,8 +169,11 @@ static int __init vas_init(void)
> > found++;
> > }
> >  
> > -   if (!found)
> > +   if (!found) {
> > +   platform_driver_unregister(_driver);
> > +   vas_cleanup_dbgdir();
> > return -ENODEV;
> > +   }
> 
> The better patch would be to move the call to vas_init_dbgdir() down
> here, where we know we have successfully registered the driver.

Well, when VAS is configured, init_vas_instance() expects the top level
"vas" debugfs dir to already be setup.

We could have each init_vas_instance() assume it is the first and
unconditionally call vas_init_dbgdir(). vas_init_dbgdir() could make
sure to initialize only once.

Or, we could make a separate pass countng "ibm,vas" nodes. If there are
none, skip both steps (dbgdir and registering platform driver).

Sukadev

[PATCH 2/4] powerpc/vas: Fix cleanup when VAS is not configured

[Sukadev Bhattiprolu]

When VAS is not configured in the system, make sure to remove
the VAS debugfs directory and unregister the platform driver.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-debug.c | 5 +
 arch/powerpc/platforms/powernv/vas.c   | 5 -
 arch/powerpc/platforms/powernv/vas.h   | 1 +
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
index b4de4c6..e6e4067 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -207,3 +207,8 @@ void vas_init_dbgdir(void)
if (IS_ERR(vas_debugfs))
vas_debugfs = NULL;
 }
+
+void vas_cleanup_dbgdir(void)
+{
+   debugfs_remove_recursive(vas_debugfs);
+}
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index aebbe95..f83e27d8 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -169,8 +169,11 @@ static int __init vas_init(void)
found++;
}
 
-   if (!found)
+   if (!found) {
+   platform_driver_unregister(_driver);
+   vas_cleanup_dbgdir();
return -ENODEV;
+   }
 
pr_devel("Found %d instances\n", found);
 
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index ae0100f..2645613 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -406,6 +406,7 @@ extern struct mutex vas_mutex;
 
 extern struct vas_instance *find_vas_instance(int vasid);
 extern void vas_init_dbgdir(void);
+extern void vas_cleanup_dbgdir(void);
 extern void vas_instance_init_dbgdir(struct vas_instance *vinst);
 extern void vas_window_init_dbgdir(struct vas_window *win);
 extern void vas_window_free_dbgdir(struct vas_window *win);
-- 
2.7.4

[PATCH 4/4] powerpc/vas: Add a couple of trace points

[Sukadev Bhattiprolu]

Add a couple of trace points in the VAS driver

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog [v2]
- Make TRACE_INCLUDE_PATH relative to 
---
 arch/powerpc/platforms/powernv/vas-trace.h  | 112 
 arch/powerpc/platforms/powernv/vas-window.c |   9 +++
 2 files changed, 121 insertions(+)
 create mode 100644 arch/powerpc/platforms/powernv/vas-trace.h

diff --git a/arch/powerpc/platforms/powernv/vas-trace.h 
b/arch/powerpc/platforms/powernv/vas-trace.h
new file mode 100644
index 000..939d85d
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-trace.h
@@ -0,0 +1,112 @@
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM   vas
+
+#if !defined(_VAS_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+
+#define _VAS_TRACE_H
+#include 
+#include 
+#include 
+
+TRACE_EVENT(   vas_rx_win_open,
+
+   TP_PROTO(struct task_struct *tsk,
+int vasid,
+int cop,
+struct vas_rx_win_attr *rxattr),
+
+   TP_ARGS(tsk, vasid, cop, rxattr),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, cop)
+   __field(int, vasid)
+   __field(struct vas_rx_win_attr *, rxattr)
+   __field(int, lnotify_lpid)
+   __field(int, lnotify_pid)
+   __field(int, lnotify_tid)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = vasid;
+   __entry->cop = cop;
+   __entry->lnotify_lpid = rxattr->lnotify_lpid;
+   __entry->lnotify_pid = rxattr->lnotify_pid;
+   __entry->lnotify_tid = rxattr->lnotify_tid;
+   ),
+
+   TP_printk("pid=%d, vasid=%d, cop=%d, lpid=%d, pid=%d, tid=%d",
+   __entry->pid, __entry->vasid, __entry->cop,
+   __entry->lnotify_lpid, __entry->lnotify_pid,
+   __entry->lnotify_tid)
+);
+
+TRACE_EVENT(   vas_tx_win_open,
+
+   TP_PROTO(struct task_struct *tsk,
+int vasid,
+int cop,
+struct vas_tx_win_attr *txattr),
+
+   TP_ARGS(tsk, vasid, cop, txattr),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, cop)
+   __field(int, vasid)
+   __field(struct vas_tx_win_attr *, txattr)
+   __field(int, lpid)
+   __field(int, pidr)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = vasid;
+   __entry->cop = cop;
+   __entry->lpid = txattr->lpid;
+   __entry->pidr = txattr->pidr;
+   ),
+
+   TP_printk("pid=%d, vasid=%d, cop=%d, lpid=%d, pidr=%d",
+   __entry->pid, __entry->vasid, __entry->cop,
+   __entry->lpid, __entry->pidr)
+);
+
+TRACE_EVENT(   vas_paste_crb,
+
+   TP_PROTO(struct task_struct *tsk,
+   struct vas_window *win),
+
+   TP_ARGS(tsk, win),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(struct vas_window *, win)
+   __field(int, pid)
+   __field(int, vasid)
+   __field(int, winid)
+   __field(unsigned long, paste_kaddr)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = win->vinst->vas_id;
+   __entry->winid = win->winid;
+   __entry->paste_kaddr = (unsigned long)win->paste_kaddr
+   ),
+
+   TP_printk("pid=%d, vasid=%d, winid=%d, paste_kaddr=0x%016lx\n",
+   __entry->pid, __entry->vasid, __entry->winid,
+   __entry->paste_kaddr)
+);
+
+#endif /* _VAS_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH ../../arch/powerpc/platforms/powernv
+#define TRACE_INCLUDE_FILE vas-trace
+#include 
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 2b3eb01..6b2de9e 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -21,6 +21,9 @@
 #inclu

[PATCH 2/4] powerpc/vas: Fix cleanup when VAS is not configured

[Sukadev Bhattiprolu]

When VAS is not configured in the system, make sure to remove
the VAS debugfs directory and unregister the platform driver.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-debug.c | 5 +
 arch/powerpc/platforms/powernv/vas.c   | 5 -
 arch/powerpc/platforms/powernv/vas.h   | 1 +
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
index b4de4c6..e6e4067 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -207,3 +207,8 @@ void vas_init_dbgdir(void)
if (IS_ERR(vas_debugfs))
vas_debugfs = NULL;
 }
+
+void vas_cleanup_dbgdir(void)
+{
+   debugfs_remove_recursive(vas_debugfs);
+}
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index aebbe95..f83e27d8 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -169,8 +169,11 @@ static int __init vas_init(void)
found++;
}
 
-   if (!found)
+   if (!found) {
+   platform_driver_unregister(_driver);
+   vas_cleanup_dbgdir();
return -ENODEV;
+   }
 
pr_devel("Found %d instances\n", found);
 
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index ae0100f..2645613 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -406,6 +406,7 @@ extern struct mutex vas_mutex;
 
 extern struct vas_instance *find_vas_instance(int vasid);
 extern void vas_init_dbgdir(void);
+extern void vas_cleanup_dbgdir(void);
 extern void vas_instance_init_dbgdir(struct vas_instance *vinst);
 extern void vas_window_init_dbgdir(struct vas_window *win);
 extern void vas_window_free_dbgdir(struct vas_window *win);
-- 
2.7.4

[PATCH 4/4] powerpc/vas: Add a couple of trace points

[Sukadev Bhattiprolu]

Add a couple of trace points in the VAS driver

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog [v2]
- Make TRACE_INCLUDE_PATH relative to 
---
 arch/powerpc/platforms/powernv/vas-trace.h  | 112 
 arch/powerpc/platforms/powernv/vas-window.c |   9 +++
 2 files changed, 121 insertions(+)
 create mode 100644 arch/powerpc/platforms/powernv/vas-trace.h

diff --git a/arch/powerpc/platforms/powernv/vas-trace.h 
b/arch/powerpc/platforms/powernv/vas-trace.h
new file mode 100644
index 000..939d85d
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-trace.h
@@ -0,0 +1,112 @@
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM   vas
+
+#if !defined(_VAS_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+
+#define _VAS_TRACE_H
+#include 
+#include 
+#include 
+
+TRACE_EVENT(   vas_rx_win_open,
+
+   TP_PROTO(struct task_struct *tsk,
+int vasid,
+int cop,
+struct vas_rx_win_attr *rxattr),
+
+   TP_ARGS(tsk, vasid, cop, rxattr),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, cop)
+   __field(int, vasid)
+   __field(struct vas_rx_win_attr *, rxattr)
+   __field(int, lnotify_lpid)
+   __field(int, lnotify_pid)
+   __field(int, lnotify_tid)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = vasid;
+   __entry->cop = cop;
+   __entry->lnotify_lpid = rxattr->lnotify_lpid;
+   __entry->lnotify_pid = rxattr->lnotify_pid;
+   __entry->lnotify_tid = rxattr->lnotify_tid;
+   ),
+
+   TP_printk("pid=%d, vasid=%d, cop=%d, lpid=%d, pid=%d, tid=%d",
+   __entry->pid, __entry->vasid, __entry->cop,
+   __entry->lnotify_lpid, __entry->lnotify_pid,
+   __entry->lnotify_tid)
+);
+
+TRACE_EVENT(   vas_tx_win_open,
+
+   TP_PROTO(struct task_struct *tsk,
+int vasid,
+int cop,
+struct vas_tx_win_attr *txattr),
+
+   TP_ARGS(tsk, vasid, cop, txattr),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, cop)
+   __field(int, vasid)
+   __field(struct vas_tx_win_attr *, txattr)
+   __field(int, lpid)
+   __field(int, pidr)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = vasid;
+   __entry->cop = cop;
+   __entry->lpid = txattr->lpid;
+   __entry->pidr = txattr->pidr;
+   ),
+
+   TP_printk("pid=%d, vasid=%d, cop=%d, lpid=%d, pidr=%d",
+   __entry->pid, __entry->vasid, __entry->cop,
+   __entry->lpid, __entry->pidr)
+);
+
+TRACE_EVENT(   vas_paste_crb,
+
+   TP_PROTO(struct task_struct *tsk,
+   struct vas_window *win),
+
+   TP_ARGS(tsk, win),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(struct vas_window *, win)
+   __field(int, pid)
+   __field(int, vasid)
+   __field(int, winid)
+   __field(unsigned long, paste_kaddr)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = win->vinst->vas_id;
+   __entry->winid = win->winid;
+   __entry->paste_kaddr = (unsigned long)win->paste_kaddr
+   ),
+
+   TP_printk("pid=%d, vasid=%d, winid=%d, paste_kaddr=0x%016lx\n",
+   __entry->pid, __entry->vasid, __entry->winid,
+   __entry->paste_kaddr)
+);
+
+#endif /* _VAS_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH ../../arch/powerpc/platforms/powernv
+#define TRACE_INCLUDE_FILE vas-trace
+#include 
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 2b3eb01..6b2de9e 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -21,6 +21,9 @@
 #include "vas.h"
 #include &

[PATCH RESEND 3/4] powerpc/vas: Remove a stray line in Makefile

[Sukadev Bhattiprolu]

Remove a bogus line from arch/powerpc/platforms/powernv/Makefile that
was added by commit ece4e51 ("powerpc/vas: Export HVWC to debugfs").

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/Makefile | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index 6c9d519..703a350 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -16,5 +16,4 @@ obj-$(CONFIG_OPAL_PRD)+= opal-prd.o
 obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
 obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
 obj-$(CONFIG_PPC_VAS)  += vas.o vas-window.o vas-debug.o
-obj-$(CONFIG_PPC_FTW)  += nx-ftw.o
 obj-$(CONFIG_OCXL_BASE)+= ocxl.o
-- 
2.7.4

[PATCH RESEND 1/4] powerpc/vas: Fix order of cleanup in debugfs dir

[Sukadev Bhattiprolu]

Fix the order of cleanup to ensure we free the name buffer in case
of an error creating 'hvwc' or 'info' files.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-debug.c | 8 
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
index ca22f1e..b4de4c6 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -166,13 +166,13 @@ void vas_window_init_dbgdir(struct vas_window *window)
 
return;
 
-free_name:
-   kfree(window->dbgname);
-   window->dbgname = NULL;
-
 remove_dir:
debugfs_remove_recursive(window->dbgdir);
window->dbgdir = NULL;
+
+free_name:
+   kfree(window->dbgname);
+   window->dbgname = NULL;
 }
 
 void vas_instance_init_dbgdir(struct vas_instance *vinst)
-- 
2.7.4

[PATCH RESEND 3/4] powerpc/vas: Remove a stray line in Makefile

[Sukadev Bhattiprolu]

Remove a bogus line from arch/powerpc/platforms/powernv/Makefile that
was added by commit ece4e51 ("powerpc/vas: Export HVWC to debugfs").

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/Makefile | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index 6c9d519..703a350 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -16,5 +16,4 @@ obj-$(CONFIG_OPAL_PRD)+= opal-prd.o
 obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
 obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
 obj-$(CONFIG_PPC_VAS)  += vas.o vas-window.o vas-debug.o
-obj-$(CONFIG_PPC_FTW)  += nx-ftw.o
 obj-$(CONFIG_OCXL_BASE)+= ocxl.o
-- 
2.7.4

[PATCH RESEND 1/4] powerpc/vas: Fix order of cleanup in debugfs dir

[Sukadev Bhattiprolu]

Fix the order of cleanup to ensure we free the name buffer in case
of an error creating 'hvwc' or 'info' files.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-debug.c | 8 
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
index ca22f1e..b4de4c6 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -166,13 +166,13 @@ void vas_window_init_dbgdir(struct vas_window *window)
 
return;
 
-free_name:
-   kfree(window->dbgname);
-   window->dbgname = NULL;
-
 remove_dir:
debugfs_remove_recursive(window->dbgdir);
window->dbgdir = NULL;
+
+free_name:
+   kfree(window->dbgname);
+   window->dbgname = NULL;
 }
 
 void vas_instance_init_dbgdir(struct vas_instance *vinst)
-- 
2.7.4

Re: [PATCH 5/5] powerpc/ftw: Document FTW API/usage

[Sukadev Bhattiprolu]

Randy Dunlap [rdun...@infradead.org] wrote:

> > +struct ftw_setup_attr ftwattr;
> > +
> > +fd = open("/dev/ftw", O_RDWR);
> > +
> > +memset(, 0, sizeof(rxattr));
> 
> Is that supposed to be ftwattr (2x above)?

Yes. I agree with your other comments as well and will send a new version.

Thanks for the detailed review.

Sukadev

Re: [PATCH 5/5] powerpc/ftw: Document FTW API/usage

[Sukadev Bhattiprolu]

Randy Dunlap [rdun...@infradead.org] wrote:

> > +struct ftw_setup_attr ftwattr;
> > +
> > +fd = open("/dev/ftw", O_RDWR);
> > +
> > +memset(, 0, sizeof(rxattr));
> 
> Is that supposed to be ftwattr (2x above)?

Yes. I agree with your other comments as well and will send a new version.

Thanks for the detailed review.

Sukadev

Re: [PATCH 3/5] powerpc/ftw: Implement a simple FTW driver

[Sukadev Bhattiprolu]

Randy Dunlap [rdun...@infradead.org] wrote:
> > +
> > +   default:
> > +   return -EINVAL;
> > +   }
> > +}
> 
> Nit:  some versions of gcc (or maybe clang) complain about a typed function
> not always having a return value in code like above, so it is often done as:

Ok.
> 
> > +static long ftw_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
> > +{
> > +   switch (cmd) {
> > +
> > +   case FTW_SETUP:
> > +   return ftw_ioc_ftw_setup(fp, arg);
> > +
> > +   default:
> > +   break;
> > +   }
> 
>   return -EINVAL;
> > +}
> 
> Do you expect to implement more ioctls?  If not, just change the switch to
> an if ().
Maybe a couple more but changed it to an 'if' for now (and fixed an
error handling issue in ftw_file_init()).

Here is the updated patch.

---
>From 344ffbcc2cd1e64dd87249d508cf6000e6e41a0c Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Date: Fri, 4 Aug 2017 16:45:34 -0500
Subject: [PATCH 3/5] powerpc/ftw: Implement a simple FTW driver

The Fast Thread Wake-up (FTW) driver provides user space applications an
interface to the low latency Core-to-Core wakeup functionality in POWER9.

This mechanism allows a thread on one core to efficiently send a message
to a "waiting thread" on another core on the same chip, using the Virtual
Accelrator Switchboard (VAS) subsystem.

This initial FTW driver implements the ioctl and mmap operations on an
FTW device node. Using these operations, a pair of application threads
can establish a "communication channel" and use the COPY, PASTE and WAIT
instructions to wait/wake up.

PATCH 5/5 documents the API and includes an example of the usage.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v2]
- [Michael Neuling] Rename from drop "nx" from name "nx-ftw".
- [Michael Neuling] Use a single VAS_FTW_SETUP ioctl to simplify
  interface.
- [Michael Ellerman] To work with paste emulation patch, mark
  PTE dirty in ->mmap() to ensure there is no fault on paste
  (the emulation patch must disable pagefaults when updating
  thread reconfig registers).
- [Randy Dunlap] Minor cleanup in ftw_ioctl().
- Fix cleanup code in ftw_file_init()
- Check return value from set_thread_tidr().
- Move driver drivers/misc/ftw.
---
 drivers/misc/Kconfig  |   1 +
 drivers/misc/Makefile |   1 +
 drivers/misc/ftw/Kconfig  |  16 +++
 drivers/misc/ftw/Makefile |   4 +
 drivers/misc/ftw/ftw.c| 346 ++
 5 files changed, 368 insertions(+)
 create mode 100644 drivers/misc/ftw/Kconfig
 create mode 100644 drivers/misc/ftw/Makefile
 create mode 100644 drivers/misc/ftw/ftw.c

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index f1a5c23..a9b161f 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -508,4 +508,5 @@ source "drivers/misc/mic/Kconfig"
 source "drivers/misc/genwqe/Kconfig"
 source "drivers/misc/echo/Kconfig"
 source "drivers/misc/cxl/Kconfig"
+source "drivers/misc/ftw/Kconfig"
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 5ca5f64..338668c 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_GENWQE)  += genwqe/
 obj-$(CONFIG_ECHO) += echo/
 obj-$(CONFIG_VEXPRESS_SYSCFG)  += vexpress-syscfg.o
 obj-$(CONFIG_CXL_BASE) += cxl/
+obj-$(CONFIG_PPC_FTW)  += ftw/
 obj-$(CONFIG_ASPEED_LPC_CTRL)  += aspeed-lpc-ctrl.o
 obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o
 obj-$(CONFIG_PCI_ENDPOINT_TEST)+= pci_endpoint_test.o
diff --git a/drivers/misc/ftw/Kconfig b/drivers/misc/ftw/Kconfig
new file mode 100644
index 000..5454d40
--- /dev/null
+++ b/drivers/misc/ftw/Kconfig
@@ -0,0 +1,16 @@
+
+config PPC_FTW
+   tristate "IBM Fast Thread-Wakeup (FTW)"
+   depends on PPC_VAS
+   default n
+   help
+  This enables support for IBM Fast Thread-Wakeup driver.
+
+  The FTW driver allows applications to utilize a low overhead
+  core-to-core wake up mechansim in the IBM Virtual Accelerator
+  Switchboard (VAS) to improve performance.
+
+  VAS adapters are found in POWER9 based systems and are required
+  for the FTW driver to be operational.
+
+  If unsure, say N.
diff --git a/drivers/misc/ftw/Makefile b/drivers/misc/ftw/Makefile
new file mode 100644
index 000..2cfe566
--- /dev/null
+++ b/drivers/misc/ftw/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+ccflags-y  := $(call cc-disable-warning, 
unused-const-variable)
+ccflags-$(CONFIG_PPC_WERROR)   += -Werror
+obj-$(CONFIG_PPC_FTW)  += ftw.o

Re: [PATCH 3/5] powerpc/ftw: Implement a simple FTW driver

[Sukadev Bhattiprolu]

Randy Dunlap [rdun...@infradead.org] wrote:
> > +
> > +   default:
> > +   return -EINVAL;
> > +   }
> > +}
> 
> Nit:  some versions of gcc (or maybe clang) complain about a typed function
> not always having a return value in code like above, so it is often done as:

Ok.
> 
> > +static long ftw_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
> > +{
> > +   switch (cmd) {
> > +
> > +   case FTW_SETUP:
> > +   return ftw_ioc_ftw_setup(fp, arg);
> > +
> > +   default:
> > +   break;
> > +   }
> 
>   return -EINVAL;
> > +}
> 
> Do you expect to implement more ioctls?  If not, just change the switch to
> an if ().
Maybe a couple more but changed it to an 'if' for now (and fixed an
error handling issue in ftw_file_init()).

Here is the updated patch.

---
>From 344ffbcc2cd1e64dd87249d508cf6000e6e41a0c Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu 
Date: Fri, 4 Aug 2017 16:45:34 -0500
Subject: [PATCH 3/5] powerpc/ftw: Implement a simple FTW driver

The Fast Thread Wake-up (FTW) driver provides user space applications an
interface to the low latency Core-to-Core wakeup functionality in POWER9.

This mechanism allows a thread on one core to efficiently send a message
to a "waiting thread" on another core on the same chip, using the Virtual
Accelrator Switchboard (VAS) subsystem.

This initial FTW driver implements the ioctl and mmap operations on an
FTW device node. Using these operations, a pair of application threads
can establish a "communication channel" and use the COPY, PASTE and WAIT
instructions to wait/wake up.

PATCH 5/5 documents the API and includes an example of the usage.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v2]
- [Michael Neuling] Rename from drop "nx" from name "nx-ftw".
- [Michael Neuling] Use a single VAS_FTW_SETUP ioctl to simplify
  interface.
- [Michael Ellerman] To work with paste emulation patch, mark
  PTE dirty in ->mmap() to ensure there is no fault on paste
  (the emulation patch must disable pagefaults when updating
  thread reconfig registers).
- [Randy Dunlap] Minor cleanup in ftw_ioctl().
- Fix cleanup code in ftw_file_init()
- Check return value from set_thread_tidr().
- Move driver drivers/misc/ftw.
---
 drivers/misc/Kconfig  |   1 +
 drivers/misc/Makefile |   1 +
 drivers/misc/ftw/Kconfig  |  16 +++
 drivers/misc/ftw/Makefile |   4 +
 drivers/misc/ftw/ftw.c| 346 ++
 5 files changed, 368 insertions(+)
 create mode 100644 drivers/misc/ftw/Kconfig
 create mode 100644 drivers/misc/ftw/Makefile
 create mode 100644 drivers/misc/ftw/ftw.c

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index f1a5c23..a9b161f 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -508,4 +508,5 @@ source "drivers/misc/mic/Kconfig"
 source "drivers/misc/genwqe/Kconfig"
 source "drivers/misc/echo/Kconfig"
 source "drivers/misc/cxl/Kconfig"
+source "drivers/misc/ftw/Kconfig"
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 5ca5f64..338668c 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_GENWQE)  += genwqe/
 obj-$(CONFIG_ECHO) += echo/
 obj-$(CONFIG_VEXPRESS_SYSCFG)  += vexpress-syscfg.o
 obj-$(CONFIG_CXL_BASE) += cxl/
+obj-$(CONFIG_PPC_FTW)  += ftw/
 obj-$(CONFIG_ASPEED_LPC_CTRL)  += aspeed-lpc-ctrl.o
 obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o
 obj-$(CONFIG_PCI_ENDPOINT_TEST)+= pci_endpoint_test.o
diff --git a/drivers/misc/ftw/Kconfig b/drivers/misc/ftw/Kconfig
new file mode 100644
index 000..5454d40
--- /dev/null
+++ b/drivers/misc/ftw/Kconfig
@@ -0,0 +1,16 @@
+
+config PPC_FTW
+   tristate "IBM Fast Thread-Wakeup (FTW)"
+   depends on PPC_VAS
+   default n
+   help
+  This enables support for IBM Fast Thread-Wakeup driver.
+
+  The FTW driver allows applications to utilize a low overhead
+  core-to-core wake up mechansim in the IBM Virtual Accelerator
+  Switchboard (VAS) to improve performance.
+
+  VAS adapters are found in POWER9 based systems and are required
+  for the FTW driver to be operational.
+
+  If unsure, say N.
diff --git a/drivers/misc/ftw/Makefile b/drivers/misc/ftw/Makefile
new file mode 100644
index 000..2cfe566
--- /dev/null
+++ b/drivers/misc/ftw/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+ccflags-y  := $(call cc-disable-warning, 
unused-const-variable)
+ccflags-$(CONFIG_PPC_WERROR)   += -Werror
+obj-$(CONFIG_PPC_FTW)  += ftw.o
diff --git a/drivers/misc/ftw/ftw.c b/drivers/misc/ftw/ftw.c
new file

Re: [PATCH 2/5] powerpc/ftw: Define FTW_SETUP ioctl API

[Sukadev Bhattiprolu]

Randy Dunlap [rdun...@infradead.org] wrote:

> > +#define FTW_FLAGS_PIN_WINDOW   0x1
> > +
> > +#define FTW_SETUP  _IOW('v', 1, struct ftw_setup_attr)
> 
> ioctls should be documented in Documentation/ioctl/ioctl-number.txt.
> Please update that file.

Ok. Here is the updated patch.

Thanks for the review.

Sukadev
---
>From 1f347c199a0b1bbc528705c8e9ddd11c825a80fc Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Date: Thu, 2 Feb 2017 06:20:07 -0500
Subject: [PATCH 2/5] powerpc/ftw: Define FTW_SETUP ioctl API

Define the FTW_SETUP ioctl interface for fast thread wakeup (FTW). A
follow-on patch will implement the FTW driver and ioctl.

Thanks to input from Ben Herrenschmidt, Michael Neuling, Michael Ellerman.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v2]
- [Michael Neuling] Use a single VAS_FTW_SETUP ioctl and simplify
  the interface.
- [Randy Dunlap] Reserve/document the ioctl number used.
---
 Documentation/ioctl/ioctl-number.txt |  1 +
 include/uapi/misc/ftw.h  | 35 +++
 2 files changed, 36 insertions(+)
 create mode 100644 include/uapi/misc/ftw.h

diff --git a/Documentation/ioctl/ioctl-number.txt 
b/Documentation/ioctl/ioctl-number.txt
index 3e3fdae..b0f323c 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -277,6 +277,7 @@ Code  Seq#(hex) Include FileComments
 'v'00-1F   linux/fs.h  conflict!
 'v'00-0F   linux/sonypi.h  conflict!
 'v'C0-FF   linux/meye.hconflict!
+'v'20-27   include/uapi/misc/ftw.h
 'w'all CERN SCI driver
 'y'00-1F   packet based user level communications
<mailto:zap...@interlan.net>
diff --git a/include/uapi/misc/ftw.h b/include/uapi/misc/ftw.h
new file mode 100644
index 000..99676b2
--- /dev/null
+++ b/include/uapi/misc/ftw.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2018 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_MISC_FTW_H
+#define _UAPI_MISC_FTW_H
+
+#include 
+#include 
+
+#define FTW_FLAGS_PIN_WINDOW   0x1
+
+/*
+ * Note: The range 0x20-27 for letter 'v' are reserved for FTW ioctls in
+ *  Documentation/ioctl/ioctl-number.txt.
+ */
+#define FTW_SETUP  _IOW('v', 0x20, struct ftw_setup_attr)
+
+struct ftw_setup_attr {
+   __s16   version;
+   __s16   vas_id; /* specific instance of vas or -1 for default */
+   __u32   reserved;
+
+   __u64   reserved1;
+
+   __u64   flags;
+   __u64   reserved2;
+};
+
+#endif /* _UAPI_MISC_FTW_H */
-- 
2.7.4

Re: [PATCH 2/5] powerpc/ftw: Define FTW_SETUP ioctl API

[Sukadev Bhattiprolu]

Randy Dunlap [rdun...@infradead.org] wrote:

> > +#define FTW_FLAGS_PIN_WINDOW   0x1
> > +
> > +#define FTW_SETUP  _IOW('v', 1, struct ftw_setup_attr)
> 
> ioctls should be documented in Documentation/ioctl/ioctl-number.txt.
> Please update that file.

Ok. Here is the updated patch.

Thanks for the review.

Sukadev
---
>From 1f347c199a0b1bbc528705c8e9ddd11c825a80fc Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu 
Date: Thu, 2 Feb 2017 06:20:07 -0500
Subject: [PATCH 2/5] powerpc/ftw: Define FTW_SETUP ioctl API

Define the FTW_SETUP ioctl interface for fast thread wakeup (FTW). A
follow-on patch will implement the FTW driver and ioctl.

Thanks to input from Ben Herrenschmidt, Michael Neuling, Michael Ellerman.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v2]
- [Michael Neuling] Use a single VAS_FTW_SETUP ioctl and simplify
  the interface.
- [Randy Dunlap] Reserve/document the ioctl number used.
---
 Documentation/ioctl/ioctl-number.txt |  1 +
 include/uapi/misc/ftw.h  | 35 +++
 2 files changed, 36 insertions(+)
 create mode 100644 include/uapi/misc/ftw.h

diff --git a/Documentation/ioctl/ioctl-number.txt 
b/Documentation/ioctl/ioctl-number.txt
index 3e3fdae..b0f323c 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -277,6 +277,7 @@ Code  Seq#(hex) Include FileComments
 'v'00-1F   linux/fs.h  conflict!
 'v'00-0F   linux/sonypi.h  conflict!
 'v'C0-FF   linux/meye.hconflict!
+'v'20-27   include/uapi/misc/ftw.h
 'w'all CERN SCI driver
 'y'00-1F   packet based user level communications
<mailto:zap...@interlan.net>
diff --git a/include/uapi/misc/ftw.h b/include/uapi/misc/ftw.h
new file mode 100644
index 000..99676b2
--- /dev/null
+++ b/include/uapi/misc/ftw.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2018 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_MISC_FTW_H
+#define _UAPI_MISC_FTW_H
+
+#include 
+#include 
+
+#define FTW_FLAGS_PIN_WINDOW   0x1
+
+/*
+ * Note: The range 0x20-27 for letter 'v' are reserved for FTW ioctls in
+ *  Documentation/ioctl/ioctl-number.txt.
+ */
+#define FTW_SETUP  _IOW('v', 0x20, struct ftw_setup_attr)
+
+struct ftw_setup_attr {
+   __s16   version;
+   __s16   vas_id; /* specific instance of vas or -1 for default */
+   __u32   reserved;
+
+   __u64   reserved1;
+
+   __u64   flags;
+   __u64   reserved2;
+};
+
+#endif /* _UAPI_MISC_FTW_H */
-- 
2.7.4

Re: [PATCH 1/2] powerpc: export thread-tidr interfaces

[Sukadev Bhattiprolu]

Frederic Barrat [fbar...@linux.vnet.ibm.com] wrote:
> Hi,
> 
> 
> > diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
> > index 2010e4c..f20c1ad 100644
> > --- a/arch/powerpc/kernel/process.c
> > +++ b/arch/powerpc/kernel/process.c
> > @@ -1560,6 +1560,7 @@ void clear_thread_tidr(struct task_struct *t)
> > free_thread_tidr(t->thread.tidr);
> > t->thread.tidr = 0;
> >   }
> > +EXPORT_SYMBOL_GPL(clear_thread_tidr);
> 
> Isn't it dangerous to export clear_thread_tidr()? Other modules may also
> have assigned the TIDR by calling set_thread_tidr(), so clearing it could
> potentially break those other modules. My understanding is that once the
> TIDR is assigned, there's no safe way to reclaim it other than the thread
> exiting. Or we would need some kind of reference counter.

Yes the FTW driver avoids calling clear_thread_tidr() for the same reasons.
I don't have a strong case for exporting clear_thread_tidr(). Here is the
updated patch, exporting just the set_thread_tidr().

Thanks,

Sukadev
---
>From 204ee3c918f8dad46c1e40d2d3730b07c10a87a3 Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Date: Mon, 15 Jan 2018 13:43:18 -0600
Subject: [PATCH 1/2] powerpc: export set_thread_tidr()

Export set_thread_tidr() so it can be used by external modules.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog  [Frederic Barrat] Don't export clear_thread_tidr()

---
 arch/powerpc/kernel/process.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 2010e4c..20df2cb2 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1592,6 +1592,7 @@ int set_thread_tidr(struct task_struct *t)
 
return 0;
 }
+EXPORT_SYMBOL_GPL(set_thread_tidr);
 
 #endif /* CONFIG_PPC64 */
 
-- 
1.8.3.1

Re: [PATCH 1/2] powerpc: export thread-tidr interfaces

[Sukadev Bhattiprolu]

Frederic Barrat [fbar...@linux.vnet.ibm.com] wrote:
> Hi,
> 
> 
> > diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
> > index 2010e4c..f20c1ad 100644
> > --- a/arch/powerpc/kernel/process.c
> > +++ b/arch/powerpc/kernel/process.c
> > @@ -1560,6 +1560,7 @@ void clear_thread_tidr(struct task_struct *t)
> > free_thread_tidr(t->thread.tidr);
> > t->thread.tidr = 0;
> >   }
> > +EXPORT_SYMBOL_GPL(clear_thread_tidr);
> 
> Isn't it dangerous to export clear_thread_tidr()? Other modules may also
> have assigned the TIDR by calling set_thread_tidr(), so clearing it could
> potentially break those other modules. My understanding is that once the
> TIDR is assigned, there's no safe way to reclaim it other than the thread
> exiting. Or we would need some kind of reference counter.

Yes the FTW driver avoids calling clear_thread_tidr() for the same reasons.
I don't have a strong case for exporting clear_thread_tidr(). Here is the
updated patch, exporting just the set_thread_tidr().

Thanks,

Sukadev
---
>From 204ee3c918f8dad46c1e40d2d3730b07c10a87a3 Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu 
Date: Mon, 15 Jan 2018 13:43:18 -0600
Subject: [PATCH 1/2] powerpc: export set_thread_tidr()

Export set_thread_tidr() so it can be used by external modules.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog  [Frederic Barrat] Don't export clear_thread_tidr()

---
 arch/powerpc/kernel/process.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 2010e4c..20df2cb2 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1592,6 +1592,7 @@ int set_thread_tidr(struct task_struct *t)
 
return 0;
 }
+EXPORT_SYMBOL_GPL(set_thread_tidr);
 
 #endif /* CONFIG_PPC64 */
 
-- 
1.8.3.1

[PATCH 1/5] powerpc/vas: Remove a stray line in Makefile

[Sukadev Bhattiprolu]

Remove a bogus line from arch/powerpc/platforms/powernv/Makefile that
was added by commit ece4e51 ("powerpc/vas: Export HVWC to debugfs").

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/Makefile | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index 3732118..ca94488 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -16,4 +16,3 @@ obj-$(CONFIG_OPAL_PRD)+= opal-prd.o
 obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
 obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
 obj-$(CONFIG_PPC_VAS)  += vas.o vas-window.o vas-debug.o
-obj-$(CONFIG_PPC_FTW)  += nx-ftw.o
-- 
2.7.4

[PATCH 1/5] powerpc/vas: Remove a stray line in Makefile

[Sukadev Bhattiprolu]

Remove a bogus line from arch/powerpc/platforms/powernv/Makefile that
was added by commit ece4e51 ("powerpc/vas: Export HVWC to debugfs").

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/Makefile | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index 3732118..ca94488 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -16,4 +16,3 @@ obj-$(CONFIG_OPAL_PRD)+= opal-prd.o
 obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
 obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
 obj-$(CONFIG_PPC_VAS)  += vas.o vas-window.o vas-debug.o
-obj-$(CONFIG_PPC_FTW)  += nx-ftw.o
-- 
2.7.4

[PATCH 3/5] powerpc/ftw: Implement a simple FTW driver

[Sukadev Bhattiprolu]

The Fast Thread Wake-up (FTW) driver provides user space applications an
interface to the low latency Core-to-Core wakeup functionality in POWER9.

This mechanism allows a thread on one core to efficiently send a message
to a "waiting thread" on another core on the same chip, using the Virtual
Accelrator Switchboard (VAS) subsystem.

This initial FTW driver implements the ioctl and mmap operations on an
FTW device node. Using these operations, a pair of application threads
can establish a "communication channel" and use the COPY, PASTE and WAIT
instructions to wait/wake up.

PATCH 5/5 documents the API and includes an example of the usage.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v2]
- [Michael Neuling] Rename from drop "nx" from name "nx-ftw".
- [Michael Neuling] Use a single VAS_FTW_SETUP ioctl to simplify
  interface.
- [Michael Ellerman] To work with paste emulation patch, mark
  PTE dirty in ->mmap() to ensure there is no fault on paste
  (the emulation patch must disable pagefaults when updating
  thread reconfig registers).
- Check return value from set_thread_tidr().
- Move driver drivers/misc/ftw.

---
 drivers/misc/Kconfig  |   1 +
 drivers/misc/Makefile |   1 +
 drivers/misc/ftw/Kconfig  |  16 +++
 drivers/misc/ftw/Makefile |   4 +
 drivers/misc/ftw/ftw.c| 346 ++
 5 files changed, 368 insertions(+)
 create mode 100644 drivers/misc/ftw/Kconfig
 create mode 100644 drivers/misc/ftw/Makefile
 create mode 100644 drivers/misc/ftw/ftw.c

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index f1a5c23..a9b161f 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -508,4 +508,5 @@ source "drivers/misc/mic/Kconfig"
 source "drivers/misc/genwqe/Kconfig"
 source "drivers/misc/echo/Kconfig"
 source "drivers/misc/cxl/Kconfig"
+source "drivers/misc/ftw/Kconfig"
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 5ca5f64..338668c 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_GENWQE)  += genwqe/
 obj-$(CONFIG_ECHO) += echo/
 obj-$(CONFIG_VEXPRESS_SYSCFG)  += vexpress-syscfg.o
 obj-$(CONFIG_CXL_BASE) += cxl/
+obj-$(CONFIG_PPC_FTW)  += ftw/
 obj-$(CONFIG_ASPEED_LPC_CTRL)  += aspeed-lpc-ctrl.o
 obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o
 obj-$(CONFIG_PCI_ENDPOINT_TEST)+= pci_endpoint_test.o
diff --git a/drivers/misc/ftw/Kconfig b/drivers/misc/ftw/Kconfig
new file mode 100644
index 000..5454d40
--- /dev/null
+++ b/drivers/misc/ftw/Kconfig
@@ -0,0 +1,16 @@
+
+config PPC_FTW
+   tristate "IBM Fast Thread-Wakeup (FTW)"
+   depends on PPC_VAS
+   default n
+   help
+  This enables support for IBM Fast Thread-Wakeup driver.
+
+  The FTW driver allows applications to utilize a low overhead
+  core-to-core wake up mechansim in the IBM Virtual Accelerator
+  Switchboard (VAS) to improve performance.
+
+  VAS adapters are found in POWER9 based systems and are required
+  for the FTW driver to be operational.
+
+  If unsure, say N.
diff --git a/drivers/misc/ftw/Makefile b/drivers/misc/ftw/Makefile
new file mode 100644
index 000..2cfe566
--- /dev/null
+++ b/drivers/misc/ftw/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+ccflags-y  := $(call cc-disable-warning, 
unused-const-variable)
+ccflags-$(CONFIG_PPC_WERROR)   += -Werror
+obj-$(CONFIG_PPC_FTW)  += ftw.o
diff --git a/drivers/misc/ftw/ftw.c b/drivers/misc/ftw/ftw.c
new file mode 100644
index 000..6fcb4e2
--- /dev/null
+++ b/drivers/misc/ftw/ftw.c
@@ -0,0 +1,346 @@
+/*
+ * Copyright 2018 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#define pr_fmt(fmt) "ftw: " fmt
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+/*
+ * FTW is a device driver used to provide user space access to the
+ * Core-to-Core aka Fast Thread Wakeup (FTW) functionality provided by
+ * the Virtual Accelerator Subsystem (VAS) in POWER9 systems. See also
+ * arch/powerpc/platforms/powernv/vas*.
+ *
+ * The driver creates the device /dev/ftw that can be used as follows:
+ *
+ * fd = open("/dev/ftw", O_RDWR);
+ * rc = ioctl(fd, FTW_SETUP, );
+ * paste_addr = mmap(NULL, PAGE_SIZE, prot, MAP_SHARED, fd, 0ULL).
+ * vas_copy(, 0, 1);
+ * vas_paste(paste_addr, 0, 1);
+ *
+ * where "vas_copy" and "vas_past

[PATCH 3/5] powerpc/ftw: Implement a simple FTW driver

[Sukadev Bhattiprolu]

The Fast Thread Wake-up (FTW) driver provides user space applications an
interface to the low latency Core-to-Core wakeup functionality in POWER9.

This mechanism allows a thread on one core to efficiently send a message
to a "waiting thread" on another core on the same chip, using the Virtual
Accelrator Switchboard (VAS) subsystem.

This initial FTW driver implements the ioctl and mmap operations on an
FTW device node. Using these operations, a pair of application threads
can establish a "communication channel" and use the COPY, PASTE and WAIT
instructions to wait/wake up.

PATCH 5/5 documents the API and includes an example of the usage.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v2]
- [Michael Neuling] Rename from drop "nx" from name "nx-ftw".
- [Michael Neuling] Use a single VAS_FTW_SETUP ioctl to simplify
  interface.
- [Michael Ellerman] To work with paste emulation patch, mark
  PTE dirty in ->mmap() to ensure there is no fault on paste
  (the emulation patch must disable pagefaults when updating
  thread reconfig registers).
- Check return value from set_thread_tidr().
- Move driver drivers/misc/ftw.

---
 drivers/misc/Kconfig  |   1 +
 drivers/misc/Makefile |   1 +
 drivers/misc/ftw/Kconfig  |  16 +++
 drivers/misc/ftw/Makefile |   4 +
 drivers/misc/ftw/ftw.c| 346 ++
 5 files changed, 368 insertions(+)
 create mode 100644 drivers/misc/ftw/Kconfig
 create mode 100644 drivers/misc/ftw/Makefile
 create mode 100644 drivers/misc/ftw/ftw.c

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index f1a5c23..a9b161f 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -508,4 +508,5 @@ source "drivers/misc/mic/Kconfig"
 source "drivers/misc/genwqe/Kconfig"
 source "drivers/misc/echo/Kconfig"
 source "drivers/misc/cxl/Kconfig"
+source "drivers/misc/ftw/Kconfig"
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 5ca5f64..338668c 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_GENWQE)  += genwqe/
 obj-$(CONFIG_ECHO) += echo/
 obj-$(CONFIG_VEXPRESS_SYSCFG)  += vexpress-syscfg.o
 obj-$(CONFIG_CXL_BASE) += cxl/
+obj-$(CONFIG_PPC_FTW)  += ftw/
 obj-$(CONFIG_ASPEED_LPC_CTRL)  += aspeed-lpc-ctrl.o
 obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o
 obj-$(CONFIG_PCI_ENDPOINT_TEST)+= pci_endpoint_test.o
diff --git a/drivers/misc/ftw/Kconfig b/drivers/misc/ftw/Kconfig
new file mode 100644
index 000..5454d40
--- /dev/null
+++ b/drivers/misc/ftw/Kconfig
@@ -0,0 +1,16 @@
+
+config PPC_FTW
+   tristate "IBM Fast Thread-Wakeup (FTW)"
+   depends on PPC_VAS
+   default n
+   help
+  This enables support for IBM Fast Thread-Wakeup driver.
+
+  The FTW driver allows applications to utilize a low overhead
+  core-to-core wake up mechansim in the IBM Virtual Accelerator
+  Switchboard (VAS) to improve performance.
+
+  VAS adapters are found in POWER9 based systems and are required
+  for the FTW driver to be operational.
+
+  If unsure, say N.
diff --git a/drivers/misc/ftw/Makefile b/drivers/misc/ftw/Makefile
new file mode 100644
index 000..2cfe566
--- /dev/null
+++ b/drivers/misc/ftw/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+ccflags-y  := $(call cc-disable-warning, 
unused-const-variable)
+ccflags-$(CONFIG_PPC_WERROR)   += -Werror
+obj-$(CONFIG_PPC_FTW)  += ftw.o
diff --git a/drivers/misc/ftw/ftw.c b/drivers/misc/ftw/ftw.c
new file mode 100644
index 000..6fcb4e2
--- /dev/null
+++ b/drivers/misc/ftw/ftw.c
@@ -0,0 +1,346 @@
+/*
+ * Copyright 2018 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#define pr_fmt(fmt) "ftw: " fmt
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+/*
+ * FTW is a device driver used to provide user space access to the
+ * Core-to-Core aka Fast Thread Wakeup (FTW) functionality provided by
+ * the Virtual Accelerator Subsystem (VAS) in POWER9 systems. See also
+ * arch/powerpc/platforms/powernv/vas*.
+ *
+ * The driver creates the device /dev/ftw that can be used as follows:
+ *
+ * fd = open("/dev/ftw", O_RDWR);
+ * rc = ioctl(fd, FTW_SETUP, );
+ * paste_addr = mmap(NULL, PAGE_SIZE, prot, MAP_SHARED, fd, 0ULL).
+ * vas_copy(, 0, 1);
+ * vas_paste(paste_addr, 0, 1);
+ *
+ * where "vas_copy" and "vas_paste" are defined in copy-paste

[PATCH 4/5] powerpc/ftw: Add a couple of trace points

[Sukadev Bhattiprolu]

Add a couple of trace points in the FTW driver

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 drivers/misc/ftw/ftw-trace.h | 75 
 drivers/misc/ftw/ftw.c   |  6 
 2 files changed, 81 insertions(+)
 create mode 100644 drivers/misc/ftw/ftw-trace.h

diff --git a/drivers/misc/ftw/ftw-trace.h b/drivers/misc/ftw/ftw-trace.h
new file mode 100644
index 000..0d96046
--- /dev/null
+++ b/drivers/misc/ftw/ftw-trace.h
@@ -0,0 +1,75 @@
+/*
+ * Copyright 2018 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM   ftw
+
+#if !defined(_FTW_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+
+#define _FTW_TRACE_H
+#include 
+#include 
+
+TRACE_EVENT(   ftw_open_event,
+
+   TP_PROTO(struct task_struct *tsk,
+int instid),
+
+   TP_ARGS(tsk, instid),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, instid)
+   __field(int, pid)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->instid = instid;
+   ),
+
+   TP_printk("pid=%d, inst=%d", __entry->pid, __entry->instid)
+);
+
+TRACE_EVENT(   ftw_mmap_event,
+
+   TP_PROTO(struct task_struct *tsk,
+int instid,
+unsigned long paste_addr,
+unsigned long vma_start),
+
+   TP_ARGS(tsk, instid, paste_addr, vma_start),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, instid)
+   __field(unsigned long, paste_addr)
+   __field(unsigned long, vma_start)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->instid = instid;
+   __entry->paste_addr = paste_addr;
+   __entry->vma_start = vma_start;
+   ),
+
+   TP_printk(
+   "pid=%d, inst=%d, pasteaddr=0x%16lx, vma_start=0x%16lx",
+   __entry->pid, __entry->instid, __entry->paste_addr,
+   __entry->vma_start)
+);
+
+#endif /* _FTW_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE ftw-trace
+#include 
diff --git a/drivers/misc/ftw/ftw.c b/drivers/misc/ftw/ftw.c
index 6fcb4e2..a01c9e6 100644
--- a/drivers/misc/ftw/ftw.c
+++ b/drivers/misc/ftw/ftw.c
@@ -21,6 +21,9 @@
 #include 
 #include 
 
+#define CREATE_TRACE_POINTS
+#include "ftw-trace.h"
+
 /*
  * FTW is a device driver used to provide user space access to the
  * Core-to-Core aka Fast Thread Wakeup (FTW) functionality provided by
@@ -81,6 +84,8 @@ static int ftw_open(struct inode *inode, struct file *fp)
 
fp->private_data = instance;
 
+   trace_ftw_open_event(current, instance->id);
+
return 0;
 }
 
@@ -234,6 +239,7 @@ static int ftw_mmap(struct file *fp, struct vm_area_struct 
*vma)
 
pr_devel("paste addr %llx at %lx, rc %d\n", paste_addr, vma->vm_start,
rc);
+   trace_ftw_mmap_event(current, instance->id, paste_addr, vma->vm_start);
 
set_thread_uses_vas();
 
-- 
2.7.4

[PATCH 4/5] powerpc/ftw: Add a couple of trace points

[Sukadev Bhattiprolu]

Add a couple of trace points in the FTW driver

Signed-off-by: Sukadev Bhattiprolu 
---
 drivers/misc/ftw/ftw-trace.h | 75 
 drivers/misc/ftw/ftw.c   |  6 
 2 files changed, 81 insertions(+)
 create mode 100644 drivers/misc/ftw/ftw-trace.h

diff --git a/drivers/misc/ftw/ftw-trace.h b/drivers/misc/ftw/ftw-trace.h
new file mode 100644
index 000..0d96046
--- /dev/null
+++ b/drivers/misc/ftw/ftw-trace.h
@@ -0,0 +1,75 @@
+/*
+ * Copyright 2018 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM   ftw
+
+#if !defined(_FTW_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+
+#define _FTW_TRACE_H
+#include 
+#include 
+
+TRACE_EVENT(   ftw_open_event,
+
+   TP_PROTO(struct task_struct *tsk,
+int instid),
+
+   TP_ARGS(tsk, instid),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, instid)
+   __field(int, pid)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->instid = instid;
+   ),
+
+   TP_printk("pid=%d, inst=%d", __entry->pid, __entry->instid)
+);
+
+TRACE_EVENT(   ftw_mmap_event,
+
+   TP_PROTO(struct task_struct *tsk,
+int instid,
+unsigned long paste_addr,
+unsigned long vma_start),
+
+   TP_ARGS(tsk, instid, paste_addr, vma_start),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, instid)
+   __field(unsigned long, paste_addr)
+   __field(unsigned long, vma_start)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->instid = instid;
+   __entry->paste_addr = paste_addr;
+   __entry->vma_start = vma_start;
+   ),
+
+   TP_printk(
+   "pid=%d, inst=%d, pasteaddr=0x%16lx, vma_start=0x%16lx",
+   __entry->pid, __entry->instid, __entry->paste_addr,
+   __entry->vma_start)
+);
+
+#endif /* _FTW_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE ftw-trace
+#include 
diff --git a/drivers/misc/ftw/ftw.c b/drivers/misc/ftw/ftw.c
index 6fcb4e2..a01c9e6 100644
--- a/drivers/misc/ftw/ftw.c
+++ b/drivers/misc/ftw/ftw.c
@@ -21,6 +21,9 @@
 #include 
 #include 
 
+#define CREATE_TRACE_POINTS
+#include "ftw-trace.h"
+
 /*
  * FTW is a device driver used to provide user space access to the
  * Core-to-Core aka Fast Thread Wakeup (FTW) functionality provided by
@@ -81,6 +84,8 @@ static int ftw_open(struct inode *inode, struct file *fp)
 
fp->private_data = instance;
 
+   trace_ftw_open_event(current, instance->id);
+
return 0;
 }
 
@@ -234,6 +239,7 @@ static int ftw_mmap(struct file *fp, struct vm_area_struct 
*vma)
 
pr_devel("paste addr %llx at %lx, rc %d\n", paste_addr, vma->vm_start,
rc);
+   trace_ftw_mmap_event(current, instance->id, paste_addr, vma->vm_start);
 
set_thread_uses_vas();
 
-- 
2.7.4

[PATCH 5/5] powerpc/ftw: Document FTW API/usage

[Sukadev Bhattiprolu]

Document the usage of the VAS Fast thread-wakeup API and add an entry in
MAINTAINERS file.

Thanks for input/comments from Benjamin Herrenschmidt, Michael Neuling,
Michael Ellerman, Robert Blackmore, Ian Munsie, Haren Myneni and Paul
Mackerras.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---

Changelog[v2]
- [Michael Neuling] Update API to use a single, VAS_FTW_SEUTP ioctl
  rather than two ioctls.
- [Michael Neuling] Drop "nx" from name "nx-ftw".

---
 Documentation/powerpc/ftw-api.txt | 283 ++
 MAINTAINERS   |   8 ++
 2 files changed, 291 insertions(+)
 create mode 100644 Documentation/powerpc/ftw-api.txt

diff --git a/Documentation/powerpc/ftw-api.txt 
b/Documentation/powerpc/ftw-api.txt
new file mode 100644
index 000..a107628
--- /dev/null
+++ b/Documentation/powerpc/ftw-api.txt
@@ -0,0 +1,283 @@
+Virtual Accelerator Switchboard and Fast Thread-Wakeup API
+
+Power9 processor supports a hardware subystem known as the Virtual
+Accelerator Switchboard (VAS) which allows two entities in the Power9
+system to efficiently exchange messages. Messages must be formatted as
+Coprocessor Request Blocks (CRB) and be submitted using the COPY/PASTE
+instructions (new in Power9).
+
+Usage of VAS depends on the entities exchanging the messages and
+currently two usages have been identified.
+
+First usage of VAS, referred to as VAS/NX involves a software thread
+submitting data compression requests to a co-processor (hardware/nest
+accelerator) aka NX engine. This usage is not yet available to user
+applications.
+
+Alternatively, VAS can be used by two software threads to efficiently
+exchange messages. Initially, this mechanism is intended to wake up a
+waiting thread quickly - i.e "fast thread wake-up (FTW)". This document
+describes the user API for this VAS/FTW mechanism.
+
+Application access to the FTW mechanism is provided through the FTW
+device node (/dev/ftw) implemented by the FTW device driver.
+
+A multi-threaded software processes that intends to use the FTW
+mechanism must first setup a channel (consisting of a pair of VAS
+windows) for the waiting and waking threads to communicate. The
+channel is set up by opening the FTW device and issuing the FTW_SETUP
+ioctl. Upon successful return from the ioctl, the waiting side of
+channel is complete and a thread can issue the "Wait" instruction
+to wait for an event.
+
+After the successful return from the FTW_SETUP ioctl, the waking
+thread must use mmap() system call on the same file descriptor and
+obtain a virtual address known as the "paste address".
+
+Once the mmap() call succeeds the setup of "waking" side of the channel
+is complete. To wake up a waiting thread, the waking thread should use
+the "COPY" and "PASTE" instructions to write a zero-filled CRB to the
+paste-address.
+
+The wait and wake up operations can be repeated as long as the paste
+address and the FTW file descriptor are valid (i.e until munmap() of
+the paste address or a close() of the FTW fd).
+
+1. FTW Device Node
+
+There is one /dev/ftw node in the system and it provides access to the
+VAS/FTW functionality.
+
+The only valid operations (system calls) on the FTW node are:
+
+- open() the device for read and write.
+
+- issue the FTW_SETUP ioctl to set up a channel.
+
+- mmap() the file descriptor
+
+- close the device node.
+
+Other file operations on the FTW node are undefined.
+
+Note that the COPY and PASTE operations go directly to the hardware
+and do not involve system calls or go through the FTW device.
+
+Although a system may have several instances of the VAS in the system
+(typically, one per P9 chip) there is just one FTW device node in
+the system.
+
+When the FTW device node is opened, the kernel assigns a suitable
+instance of VAS to the process. Kernel will make a best-effort attempt
+to assign an optimal instance of VAS for the process - based on the CPU/
+chip that the process is running on. In the initial release, the kernel
+does not support migrating the VAS instance if the process migrates from
+a CPU on one chip to a CPU on another chip.
+
+Applications may chose a specific instance of the VAS using the 'vas_id'
+field in the FTW_SETUP ioctl as detailed below.
+
+2. Open FTW node
+
+The device should be opened for read and write. No special privileges
+are needed to open the device. The device may be opened multiple times.
+
+Each open() of the FTW device is associated with one channel of
+communication. There is a system-wide limit (currently 64K windows per
+chip and since some are reserved for hardware, there are a

[PATCH 5/5] powerpc/ftw: Document FTW API/usage

[Sukadev Bhattiprolu]

Document the usage of the VAS Fast thread-wakeup API and add an entry in
MAINTAINERS file.

Thanks for input/comments from Benjamin Herrenschmidt, Michael Neuling,
Michael Ellerman, Robert Blackmore, Ian Munsie, Haren Myneni and Paul
Mackerras.

Signed-off-by: Sukadev Bhattiprolu 
---

Changelog[v2]
- [Michael Neuling] Update API to use a single, VAS_FTW_SEUTP ioctl
  rather than two ioctls.
- [Michael Neuling] Drop "nx" from name "nx-ftw".

---
 Documentation/powerpc/ftw-api.txt | 283 ++
 MAINTAINERS   |   8 ++
 2 files changed, 291 insertions(+)
 create mode 100644 Documentation/powerpc/ftw-api.txt

diff --git a/Documentation/powerpc/ftw-api.txt 
b/Documentation/powerpc/ftw-api.txt
new file mode 100644
index 000..a107628
--- /dev/null
+++ b/Documentation/powerpc/ftw-api.txt
@@ -0,0 +1,283 @@
+Virtual Accelerator Switchboard and Fast Thread-Wakeup API
+
+Power9 processor supports a hardware subystem known as the Virtual
+Accelerator Switchboard (VAS) which allows two entities in the Power9
+system to efficiently exchange messages. Messages must be formatted as
+Coprocessor Request Blocks (CRB) and be submitted using the COPY/PASTE
+instructions (new in Power9).
+
+Usage of VAS depends on the entities exchanging the messages and
+currently two usages have been identified.
+
+First usage of VAS, referred to as VAS/NX involves a software thread
+submitting data compression requests to a co-processor (hardware/nest
+accelerator) aka NX engine. This usage is not yet available to user
+applications.
+
+Alternatively, VAS can be used by two software threads to efficiently
+exchange messages. Initially, this mechanism is intended to wake up a
+waiting thread quickly - i.e "fast thread wake-up (FTW)". This document
+describes the user API for this VAS/FTW mechanism.
+
+Application access to the FTW mechanism is provided through the FTW
+device node (/dev/ftw) implemented by the FTW device driver.
+
+A multi-threaded software processes that intends to use the FTW
+mechanism must first setup a channel (consisting of a pair of VAS
+windows) for the waiting and waking threads to communicate. The
+channel is set up by opening the FTW device and issuing the FTW_SETUP
+ioctl. Upon successful return from the ioctl, the waiting side of
+channel is complete and a thread can issue the "Wait" instruction
+to wait for an event.
+
+After the successful return from the FTW_SETUP ioctl, the waking
+thread must use mmap() system call on the same file descriptor and
+obtain a virtual address known as the "paste address".
+
+Once the mmap() call succeeds the setup of "waking" side of the channel
+is complete. To wake up a waiting thread, the waking thread should use
+the "COPY" and "PASTE" instructions to write a zero-filled CRB to the
+paste-address.
+
+The wait and wake up operations can be repeated as long as the paste
+address and the FTW file descriptor are valid (i.e until munmap() of
+the paste address or a close() of the FTW fd).
+
+1. FTW Device Node
+
+There is one /dev/ftw node in the system and it provides access to the
+VAS/FTW functionality.
+
+The only valid operations (system calls) on the FTW node are:
+
+- open() the device for read and write.
+
+- issue the FTW_SETUP ioctl to set up a channel.
+
+- mmap() the file descriptor
+
+- close the device node.
+
+Other file operations on the FTW node are undefined.
+
+Note that the COPY and PASTE operations go directly to the hardware
+and do not involve system calls or go through the FTW device.
+
+Although a system may have several instances of the VAS in the system
+(typically, one per P9 chip) there is just one FTW device node in
+the system.
+
+When the FTW device node is opened, the kernel assigns a suitable
+instance of VAS to the process. Kernel will make a best-effort attempt
+to assign an optimal instance of VAS for the process - based on the CPU/
+chip that the process is running on. In the initial release, the kernel
+does not support migrating the VAS instance if the process migrates from
+a CPU on one chip to a CPU on another chip.
+
+Applications may chose a specific instance of the VAS using the 'vas_id'
+field in the FTW_SETUP ioctl as detailed below.
+
+2. Open FTW node
+
+The device should be opened for read and write. No special privileges
+are needed to open the device. The device may be opened multiple times.
+
+Each open() of the FTW device is associated with one channel of
+communication. There is a system-wide limit (currently 64K windows per
+chip and since some are reserved for hardware, there are about 32K
+channels per

[PATCH 2/5] powerpc/ftw: Define FTW_SETUP ioctl API

[Sukadev Bhattiprolu]

Define the FTW_SETUP ioctl interface for fast thread wakeup (FTW). A
follow-on patch will implement the FTW driver and ioctl.

Thanks to input from Ben Herrenschmidt, Michael Neuling, Michael Ellerman.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v2]
- [Michael Neuling] Use a single VAS_FTW_SETUP ioctl and simplify
  the interface.
---
 include/uapi/misc/ftw.h | 31 +++
 1 file changed, 31 insertions(+)
 create mode 100644 include/uapi/misc/ftw.h

diff --git a/include/uapi/misc/ftw.h b/include/uapi/misc/ftw.h
new file mode 100644
index 000..f233f51
--- /dev/null
+++ b/include/uapi/misc/ftw.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2018 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_MISC_FTW_H
+#define _UAPI_MISC_FTW_H
+
+#include 
+#include 
+
+#define FTW_FLAGS_PIN_WINDOW   0x1
+
+#define FTW_SETUP  _IOW('v', 1, struct ftw_setup_attr)
+
+struct ftw_setup_attr {
+   __s16   version;
+   __s16   vas_id; /* specific instance of vas or -1 for default */
+   __u32   reserved;
+
+   __u64   reserved1;
+
+   __u64   flags;
+   __u64   reserved2;
+};
+
+#endif /* _UAPI_MISC_FTW_H */
-- 
2.7.4

[PATCH 2/5] powerpc/ftw: Define FTW_SETUP ioctl API

[Sukadev Bhattiprolu]

Define the FTW_SETUP ioctl interface for fast thread wakeup (FTW). A
follow-on patch will implement the FTW driver and ioctl.

Thanks to input from Ben Herrenschmidt, Michael Neuling, Michael Ellerman.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v2]
- [Michael Neuling] Use a single VAS_FTW_SETUP ioctl and simplify
  the interface.
---
 include/uapi/misc/ftw.h | 31 +++
 1 file changed, 31 insertions(+)
 create mode 100644 include/uapi/misc/ftw.h

diff --git a/include/uapi/misc/ftw.h b/include/uapi/misc/ftw.h
new file mode 100644
index 000..f233f51
--- /dev/null
+++ b/include/uapi/misc/ftw.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2018 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_MISC_FTW_H
+#define _UAPI_MISC_FTW_H
+
+#include 
+#include 
+
+#define FTW_FLAGS_PIN_WINDOW   0x1
+
+#define FTW_SETUP  _IOW('v', 1, struct ftw_setup_attr)
+
+struct ftw_setup_attr {
+   __s16   version;
+   __s16   vas_id; /* specific instance of vas or -1 for default */
+   __u32   reserved;
+
+   __u64   reserved1;
+
+   __u64   flags;
+   __u64   reserved2;
+};
+
+#endif /* _UAPI_MISC_FTW_H */
-- 
2.7.4

[PATCH 0/5] Implement FTW driver

[Sukadev Bhattiprolu]

The Virtual Accelerator Switchboard (VAS) subsystem in the POWER9 processor
provides a low latency Core-to-core wakeup" mechanism which allows a thread
on one core the processor to efficiently send a message to a thread waiting
on another core.

This Fast thread-wakeup (FTW) driver provides user space applications an
interface to the Core-to-core wakeup mechanism. The FTW driver uses the
"external" interfaces provided by the VAS driver to interact with the VAS
hardware.

PATCH 5/5 documents the API.

The ftw-next branch on my github has some initial test cases for the
driver:

https://github.com/sukadev/linux/tree/ftw-next

Thanks to input from Ben Herrenschmidt, Michael Ellerman, Michael
Neuling and Robert Blackmore.

Sukadev Bhattiprolu (5):
  powerpc/vas: Remove a stray line in Makefile
  powerpc/ftw: Define FTW_SETUP ioctl API
  powerpc/ftw: Implement a simple FTW driver
  powerpc/ftw: Add a couple of trace points
  powerpc/ftw: Document FTW API/usage

 Documentation/powerpc/ftw-api.txt   | 283 +
 MAINTAINERS |   8 +
 arch/powerpc/platforms/powernv/Makefile |   1 -
 drivers/misc/Kconfig|   1 +
 drivers/misc/Makefile   |   1 +
 drivers/misc/ftw/Kconfig|  16 ++
 drivers/misc/ftw/Makefile   |   4 +
 drivers/misc/ftw/ftw-trace.h|  75 +++
 drivers/misc/ftw/ftw.c  | 352 
 include/uapi/misc/ftw.h |  31 +++
 10 files changed, 771 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/powerpc/ftw-api.txt
 create mode 100644 drivers/misc/ftw/Kconfig
 create mode 100644 drivers/misc/ftw/Makefile
 create mode 100644 drivers/misc/ftw/ftw-trace.h
 create mode 100644 drivers/misc/ftw/ftw.c
 create mode 100644 include/uapi/misc/ftw.h

-- 
2.7.4

[PATCH 0/5] Implement FTW driver

[Sukadev Bhattiprolu]

The Virtual Accelerator Switchboard (VAS) subsystem in the POWER9 processor
provides a low latency Core-to-core wakeup" mechanism which allows a thread
on one core the processor to efficiently send a message to a thread waiting
on another core.

This Fast thread-wakeup (FTW) driver provides user space applications an
interface to the Core-to-core wakeup mechanism. The FTW driver uses the
"external" interfaces provided by the VAS driver to interact with the VAS
hardware.

PATCH 5/5 documents the API.

The ftw-next branch on my github has some initial test cases for the
driver:

https://github.com/sukadev/linux/tree/ftw-next

Thanks to input from Ben Herrenschmidt, Michael Ellerman, Michael
Neuling and Robert Blackmore.

Sukadev Bhattiprolu (5):
  powerpc/vas: Remove a stray line in Makefile
  powerpc/ftw: Define FTW_SETUP ioctl API
  powerpc/ftw: Implement a simple FTW driver
  powerpc/ftw: Add a couple of trace points
  powerpc/ftw: Document FTW API/usage

 Documentation/powerpc/ftw-api.txt   | 283 +
 MAINTAINERS |   8 +
 arch/powerpc/platforms/powernv/Makefile |   1 -
 drivers/misc/Kconfig|   1 +
 drivers/misc/Makefile   |   1 +
 drivers/misc/ftw/Kconfig|  16 ++
 drivers/misc/ftw/Makefile   |   4 +
 drivers/misc/ftw/ftw-trace.h|  75 +++
 drivers/misc/ftw/ftw.c  | 352 
 include/uapi/misc/ftw.h |  31 +++
 10 files changed, 771 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/powerpc/ftw-api.txt
 create mode 100644 drivers/misc/ftw/Kconfig
 create mode 100644 drivers/misc/ftw/Makefile
 create mode 100644 drivers/misc/ftw/ftw-trace.h
 create mode 100644 drivers/misc/ftw/ftw.c
 create mode 100644 include/uapi/misc/ftw.h

-- 
2.7.4

[PATCH 1/1] powerpc/vas: Add a couple of trace points

[Sukadev Bhattiprolu]

Add a couple of trace points in the VAS driver.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-trace.h  | 112 
 arch/powerpc/platforms/powernv/vas-window.c |   9 +++
 2 files changed, 121 insertions(+)
 create mode 100644 arch/powerpc/platforms/powernv/vas-trace.h

diff --git a/arch/powerpc/platforms/powernv/vas-trace.h 
b/arch/powerpc/platforms/powernv/vas-trace.h
new file mode 100644
index 000..c937191
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-trace.h
@@ -0,0 +1,112 @@
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM   vas
+
+#if !defined(_VAS_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+
+#define _VAS_TRACE_H
+#include 
+#include 
+#include 
+
+TRACE_EVENT(   vas_rx_win_open,
+
+   TP_PROTO(struct task_struct *tsk,
+int vasid,
+int cop,
+struct vas_rx_win_attr *rxattr),
+
+   TP_ARGS(tsk, vasid, cop, rxattr),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, cop)
+   __field(int, vasid)
+   __field(struct vas_rx_win_attr *, rxattr)
+   __field(int, lnotify_lpid)
+   __field(int, lnotify_pid)
+   __field(int, lnotify_tid)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = vasid;
+   __entry->cop = cop;
+   __entry->lnotify_lpid = rxattr->lnotify_lpid;
+   __entry->lnotify_pid = rxattr->lnotify_pid;
+   __entry->lnotify_tid = rxattr->lnotify_tid;
+   ),
+
+   TP_printk("pid=%d, vasid=%d, cop=%d, lpid=%d, pid=%d, tid=%d",
+   __entry->pid, __entry->vasid, __entry->cop,
+   __entry->lnotify_lpid, __entry->lnotify_pid,
+   __entry->lnotify_tid)
+);
+
+TRACE_EVENT(   vas_tx_win_open,
+
+   TP_PROTO(struct task_struct *tsk,
+int vasid,
+int cop,
+struct vas_tx_win_attr *txattr),
+
+   TP_ARGS(tsk, vasid, cop, txattr),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, cop)
+   __field(int, vasid)
+   __field(struct vas_tx_win_attr *, txattr)
+   __field(int, lpid)
+   __field(int, pidr)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = vasid;
+   __entry->cop = cop;
+   __entry->lpid = txattr->lpid;
+   __entry->pidr = txattr->pidr;
+   ),
+
+   TP_printk("pid=%d, vasid=%d, cop=%d, lpid=%d, pidr=%d",
+   __entry->pid, __entry->vasid, __entry->cop,
+   __entry->lpid, __entry->pidr)
+);
+
+TRACE_EVENT(   vas_paste_crb,
+
+   TP_PROTO(struct task_struct *tsk,
+   struct vas_window *win),
+
+   TP_ARGS(tsk, win),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(struct vas_window *, win)
+   __field(int, pid)
+   __field(int, vasid)
+   __field(int, winid)
+   __field(unsigned long, paste_kaddr)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = win->vinst->vas_id;
+   __entry->winid = win->winid;
+   __entry->paste_kaddr = (unsigned long)win->paste_kaddr
+   ),
+
+   TP_printk("pid=%d, vasid=%d, winid=%d, paste_kaddr=0x%016lx\n",
+   __entry->pid, __entry->vasid, __entry->winid,
+   __entry->paste_kaddr)
+);
+
+#endif /* _VAS_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE vas-trace
+#include 
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 2b3eb01..6b2de9e 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -21,6 +21,9 @@
 #include "vas.h"
 #include "copy-paste.h"
 
+#define CREATE_TRACE_POINTS
+#incl

[PATCH 1/1] powerpc/vas: Add a couple of trace points

[Sukadev Bhattiprolu]

Add a couple of trace points in the VAS driver.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-trace.h  | 112 
 arch/powerpc/platforms/powernv/vas-window.c |   9 +++
 2 files changed, 121 insertions(+)
 create mode 100644 arch/powerpc/platforms/powernv/vas-trace.h

diff --git a/arch/powerpc/platforms/powernv/vas-trace.h 
b/arch/powerpc/platforms/powernv/vas-trace.h
new file mode 100644
index 000..c937191
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-trace.h
@@ -0,0 +1,112 @@
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM   vas
+
+#if !defined(_VAS_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+
+#define _VAS_TRACE_H
+#include 
+#include 
+#include 
+
+TRACE_EVENT(   vas_rx_win_open,
+
+   TP_PROTO(struct task_struct *tsk,
+int vasid,
+int cop,
+struct vas_rx_win_attr *rxattr),
+
+   TP_ARGS(tsk, vasid, cop, rxattr),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, cop)
+   __field(int, vasid)
+   __field(struct vas_rx_win_attr *, rxattr)
+   __field(int, lnotify_lpid)
+   __field(int, lnotify_pid)
+   __field(int, lnotify_tid)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = vasid;
+   __entry->cop = cop;
+   __entry->lnotify_lpid = rxattr->lnotify_lpid;
+   __entry->lnotify_pid = rxattr->lnotify_pid;
+   __entry->lnotify_tid = rxattr->lnotify_tid;
+   ),
+
+   TP_printk("pid=%d, vasid=%d, cop=%d, lpid=%d, pid=%d, tid=%d",
+   __entry->pid, __entry->vasid, __entry->cop,
+   __entry->lnotify_lpid, __entry->lnotify_pid,
+   __entry->lnotify_tid)
+);
+
+TRACE_EVENT(   vas_tx_win_open,
+
+   TP_PROTO(struct task_struct *tsk,
+int vasid,
+int cop,
+struct vas_tx_win_attr *txattr),
+
+   TP_ARGS(tsk, vasid, cop, txattr),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(int, pid)
+   __field(int, cop)
+   __field(int, vasid)
+   __field(struct vas_tx_win_attr *, txattr)
+   __field(int, lpid)
+   __field(int, pidr)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = vasid;
+   __entry->cop = cop;
+   __entry->lpid = txattr->lpid;
+   __entry->pidr = txattr->pidr;
+   ),
+
+   TP_printk("pid=%d, vasid=%d, cop=%d, lpid=%d, pidr=%d",
+   __entry->pid, __entry->vasid, __entry->cop,
+   __entry->lpid, __entry->pidr)
+);
+
+TRACE_EVENT(   vas_paste_crb,
+
+   TP_PROTO(struct task_struct *tsk,
+   struct vas_window *win),
+
+   TP_ARGS(tsk, win),
+
+   TP_STRUCT__entry(
+   __field(struct task_struct *, tsk)
+   __field(struct vas_window *, win)
+   __field(int, pid)
+   __field(int, vasid)
+   __field(int, winid)
+   __field(unsigned long, paste_kaddr)
+   ),
+
+   TP_fast_assign(
+   __entry->pid = tsk->pid;
+   __entry->vasid = win->vinst->vas_id;
+   __entry->winid = win->winid;
+   __entry->paste_kaddr = (unsigned long)win->paste_kaddr
+   ),
+
+   TP_printk("pid=%d, vasid=%d, winid=%d, paste_kaddr=0x%016lx\n",
+   __entry->pid, __entry->vasid, __entry->winid,
+   __entry->paste_kaddr)
+);
+
+#endif /* _VAS_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE vas-trace
+#include 
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 2b3eb01..6b2de9e 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -21,6 +21,9 @@
 #include "vas.h"
 #include "copy-paste.h"
 
+#define CREATE_TRACE_POINTS
+#include "vas-trace.h"

[PATCH 2/2] powerpc: export set_thread_uses_vas()

[Sukadev Bhattiprolu]

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/process.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index f20c1ad..d22055b 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1475,6 +1475,7 @@ int set_thread_uses_vas(void)
 #endif /* CONFIG_PPC_BOOK3S_64 */
return 0;
 }
+EXPORT_SYMBOL_GPL(set_thread_uses_vas);
 
 #ifdef CONFIG_PPC64
 static DEFINE_SPINLOCK(vas_thread_id_lock);
-- 
2.7.4

[PATCH 2/2] powerpc: export set_thread_uses_vas()

[Sukadev Bhattiprolu]

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/kernel/process.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index f20c1ad..d22055b 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1475,6 +1475,7 @@ int set_thread_uses_vas(void)
 #endif /* CONFIG_PPC_BOOK3S_64 */
return 0;
 }
+EXPORT_SYMBOL_GPL(set_thread_uses_vas);
 
 #ifdef CONFIG_PPC64
 static DEFINE_SPINLOCK(vas_thread_id_lock);
-- 
2.7.4

[PATCH 1/2] powerpc: export thread-tidr interfaces

[Sukadev Bhattiprolu]

Export set_thread_tidr() and clear_thread_tidr() interfaces so they
can be used by external modules.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/process.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 2010e4c..f20c1ad 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1560,6 +1560,7 @@ void clear_thread_tidr(struct task_struct *t)
free_thread_tidr(t->thread.tidr);
t->thread.tidr = 0;
 }
+EXPORT_SYMBOL_GPL(clear_thread_tidr);
 
 void arch_release_task_struct(struct task_struct *t)
 {
@@ -1592,6 +1593,7 @@ int set_thread_tidr(struct task_struct *t)
 
return 0;
 }
+EXPORT_SYMBOL_GPL(set_thread_tidr);
 
 #endif /* CONFIG_PPC64 */
 
-- 
2.7.4

[PATCH 1/2] powerpc: export thread-tidr interfaces

[Sukadev Bhattiprolu]

Export set_thread_tidr() and clear_thread_tidr() interfaces so they
can be used by external modules.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/kernel/process.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 2010e4c..f20c1ad 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1560,6 +1560,7 @@ void clear_thread_tidr(struct task_struct *t)
free_thread_tidr(t->thread.tidr);
t->thread.tidr = 0;
 }
+EXPORT_SYMBOL_GPL(clear_thread_tidr);
 
 void arch_release_task_struct(struct task_struct *t)
 {
@@ -1592,6 +1593,7 @@ int set_thread_tidr(struct task_struct *t)
 
return 0;
 }
+EXPORT_SYMBOL_GPL(set_thread_tidr);
 
 #endif /* CONFIG_PPC64 */
 
-- 
2.7.4

[PATCH 1/1] powerpc: Emulate paste instruction

[Sukadev Bhattiprolu]

From: Michael Neuling <mi...@neuling.org>

On POWER9 DD2.1 and below there are issues when the paste instruction
generates an error. If an error occurs when thread reconfiguration
happens (ie another thread in the core goes into/out of powersave) the
core may hang.

To avoid this a special sequence is required which stops thread
configuration so that the paste can be safely executed.

This patch assumes paste executed in userspace are trapped into the
illegal instruction exception at 0xe40.

Here we re-execute the paste instruction but with the required
sequence to ensure thread reconfiguration doesn't occur.

Signed-off-by: Michael Neuling <mi...@neuling.org>
Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v4]:
- We need to disable pagefaults after all when modifying the thread
  reconfig registers. Use a mutex, rather than a spinlock around
  the thread reconfig registers. Acquire the mutex first then block
  interrupts so we don't sleep on the mutex with interrupts disabled.

Changlog[v3]:
- [Michael Ellerman] We don't need to disable/enable pagefaults
  when emulating paste;
- [Michael Ellerman, Aneesh Kumar] Fix retval from emulate_paste()

Changelog[v2]:
[Sukadev]: Use PPC_PASTE() rather than the paste instruction since
in older versions the instruction required a third parameter.
---
 arch/powerpc/include/asm/emulated_ops.h |  1 +
 arch/powerpc/include/asm/ppc-opcode.h   |  1 +
 arch/powerpc/include/asm/reg.h  |  2 +
 arch/powerpc/kernel/traps.c | 73 +
 4 files changed, 77 insertions(+)

diff --git a/arch/powerpc/include/asm/emulated_ops.h 
b/arch/powerpc/include/asm/emulated_ops.h
index 651e135..fdc95cf 100644
--- a/arch/powerpc/include/asm/emulated_ops.h
+++ b/arch/powerpc/include/asm/emulated_ops.h
@@ -59,6 +59,7 @@ extern struct ppc_emulated {
struct ppc_emulated_entry lxvh8x;
struct ppc_emulated_entry lxvd2x;
struct ppc_emulated_entry lxvb16x;
+   struct ppc_emulated_entry paste;
 #endif
 } ppc_emulated;
 
diff --git a/arch/powerpc/include/asm/ppc-opcode.h 
b/arch/powerpc/include/asm/ppc-opcode.h
index ce0930d..a55d2ef 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -229,6 +229,7 @@
 #define PPC_INST_MTTMR 0x7c0003dc
 #define PPC_INST_NOP   0x6000
 #define PPC_INST_PASTE 0x7c20070d
+#define PPC_INST_PASTE_MASK0xfc2007ff
 #define PPC_INST_POPCNTB   0x7cf4
 #define PPC_INST_POPCNTB_MASK  0xfc0007fe
 #define PPC_INST_POPCNTD   0x7c0003f4
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index b779f3c..3495ecf 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -469,6 +469,8 @@
 #define SPRN_DBAT7U0x23E   /* Data BAT 7 Upper Register */
 #define SPRN_PPR   0x380   /* SMT Thread status Register */
 #define SPRN_TSCR  0x399   /* Thread Switch Control Register */
+#define SPRN_TRIG1 0x371   /* WAT Trigger 1 */
+#define SPRN_TRIG2 0x372   /* WAT Trigger 2 */
 
 #define SPRN_DEC   0x016   /* Decrement Register */
 #define SPRN_DER   0x095   /* Debug Enable Register */
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index f3eb61b..e1ea3be 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1153,6 +1153,74 @@ static inline bool tm_abort_check(struct pt_regs *regs, 
int reason)
 }
 #endif
 
+static DEFINE_MUTEX(paste_emulation_mutex);
+
+static inline int paste(void *i)
+{
+   int cr;
+   long retval = 0;
+
+   /* Need per core lock to ensure trig1/2 writes don't race */
+   mutex_lock(_emulation_mutex);
+
+   hard_irq_disable();
+
+   mtspr(SPRN_TRIG1, 0); /* data doesn't matter */
+   mtspr(SPRN_TRIG1, 0); /* HW says do this twice */
+   asm volatile(
+   "1: " PPC_PASTE(0, %2) "\n"
+   "2: mfcr %1\n"
+   ".section .fixup,\"ax\"\n"
+   "3: li %0,%3\n"
+   "   li %2,0\n"
+   "   b 2b\n"
+   ".previous\n"
+   EX_TABLE(1b, 3b)
+   : "=r" (retval), "=r" (cr)
+   : "b" (i), "i" (-EFAULT), "0" (retval));
+   mtspr(SPRN_TRIG2, 0);
+
+   local_irq_enable();
+
+   mutex_unlock(_emulation_mutex);
+
+   return retval ? retval : cr;
+}
+
+static int emulate_paste(struct pt_regs *regs, u32 instword)
+{
+   const void __user *addr;
+   unsigned long ea;
+   u8 ra, rb;
+   int rc;
+
+   if (!cpu_has_feature(CPU_FTR_ARCH_300))
+   return -EINVAL;
+
+   ra = (instword &

[PATCH 1/1] powerpc: Emulate paste instruction

[Sukadev Bhattiprolu]

From: Michael Neuling 

On POWER9 DD2.1 and below there are issues when the paste instruction
generates an error. If an error occurs when thread reconfiguration
happens (ie another thread in the core goes into/out of powersave) the
core may hang.

To avoid this a special sequence is required which stops thread
configuration so that the paste can be safely executed.

This patch assumes paste executed in userspace are trapped into the
illegal instruction exception at 0xe40.

Here we re-execute the paste instruction but with the required
sequence to ensure thread reconfiguration doesn't occur.

Signed-off-by: Michael Neuling 
Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v4]:
- We need to disable pagefaults after all when modifying the thread
  reconfig registers. Use a mutex, rather than a spinlock around
  the thread reconfig registers. Acquire the mutex first then block
  interrupts so we don't sleep on the mutex with interrupts disabled.

Changlog[v3]:
- [Michael Ellerman] We don't need to disable/enable pagefaults
  when emulating paste;
- [Michael Ellerman, Aneesh Kumar] Fix retval from emulate_paste()

Changelog[v2]:
[Sukadev]: Use PPC_PASTE() rather than the paste instruction since
in older versions the instruction required a third parameter.
---
 arch/powerpc/include/asm/emulated_ops.h |  1 +
 arch/powerpc/include/asm/ppc-opcode.h   |  1 +
 arch/powerpc/include/asm/reg.h  |  2 +
 arch/powerpc/kernel/traps.c | 73 +
 4 files changed, 77 insertions(+)

diff --git a/arch/powerpc/include/asm/emulated_ops.h 
b/arch/powerpc/include/asm/emulated_ops.h
index 651e135..fdc95cf 100644
--- a/arch/powerpc/include/asm/emulated_ops.h
+++ b/arch/powerpc/include/asm/emulated_ops.h
@@ -59,6 +59,7 @@ extern struct ppc_emulated {
struct ppc_emulated_entry lxvh8x;
struct ppc_emulated_entry lxvd2x;
struct ppc_emulated_entry lxvb16x;
+   struct ppc_emulated_entry paste;
 #endif
 } ppc_emulated;
 
diff --git a/arch/powerpc/include/asm/ppc-opcode.h 
b/arch/powerpc/include/asm/ppc-opcode.h
index ce0930d..a55d2ef 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -229,6 +229,7 @@
 #define PPC_INST_MTTMR 0x7c0003dc
 #define PPC_INST_NOP   0x6000
 #define PPC_INST_PASTE 0x7c20070d
+#define PPC_INST_PASTE_MASK0xfc2007ff
 #define PPC_INST_POPCNTB   0x7cf4
 #define PPC_INST_POPCNTB_MASK  0xfc0007fe
 #define PPC_INST_POPCNTD   0x7c0003f4
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index b779f3c..3495ecf 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -469,6 +469,8 @@
 #define SPRN_DBAT7U0x23E   /* Data BAT 7 Upper Register */
 #define SPRN_PPR   0x380   /* SMT Thread status Register */
 #define SPRN_TSCR  0x399   /* Thread Switch Control Register */
+#define SPRN_TRIG1 0x371   /* WAT Trigger 1 */
+#define SPRN_TRIG2 0x372   /* WAT Trigger 2 */
 
 #define SPRN_DEC   0x016   /* Decrement Register */
 #define SPRN_DER   0x095   /* Debug Enable Register */
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index f3eb61b..e1ea3be 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1153,6 +1153,74 @@ static inline bool tm_abort_check(struct pt_regs *regs, 
int reason)
 }
 #endif
 
+static DEFINE_MUTEX(paste_emulation_mutex);
+
+static inline int paste(void *i)
+{
+   int cr;
+   long retval = 0;
+
+   /* Need per core lock to ensure trig1/2 writes don't race */
+   mutex_lock(_emulation_mutex);
+
+   hard_irq_disable();
+
+   mtspr(SPRN_TRIG1, 0); /* data doesn't matter */
+   mtspr(SPRN_TRIG1, 0); /* HW says do this twice */
+   asm volatile(
+   "1: " PPC_PASTE(0, %2) "\n"
+   "2: mfcr %1\n"
+   ".section .fixup,\"ax\"\n"
+   "3: li %0,%3\n"
+   "   li %2,0\n"
+   "   b 2b\n"
+   ".previous\n"
+   EX_TABLE(1b, 3b)
+   : "=r" (retval), "=r" (cr)
+   : "b" (i), "i" (-EFAULT), "0" (retval));
+   mtspr(SPRN_TRIG2, 0);
+
+   local_irq_enable();
+
+   mutex_unlock(_emulation_mutex);
+
+   return retval ? retval : cr;
+}
+
+static int emulate_paste(struct pt_regs *regs, u32 instword)
+{
+   const void __user *addr;
+   unsigned long ea;
+   u8 ra, rb;
+   int rc;
+
+   if (!cpu_has_feature(CPU_FTR_ARCH_300))
+   return -EINVAL;
+
+   ra = (instword >> 16) & 0x1f;
+   rb = (instword >> 11) & 0x1f;
+
+   

[PATCH 1/1] vas: vas_window_init_dbgdir: fix order of cleanup.

[Sukadev Bhattiprolu]

Fix the order of cleanup to ensure we free the name buffer in case
of an error creating 'hvwc' or 'info' files.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-debug.c | 8 
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
index ca22f1e..b4de4c6 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -166,13 +166,13 @@ void vas_window_init_dbgdir(struct vas_window *window)
 
return;
 
-free_name:
-   kfree(window->dbgname);
-   window->dbgname = NULL;
-
 remove_dir:
debugfs_remove_recursive(window->dbgdir);
window->dbgdir = NULL;
+
+free_name:
+   kfree(window->dbgname);
+   window->dbgname = NULL;
 }
 
 void vas_instance_init_dbgdir(struct vas_instance *vinst)
-- 
2.7.4

[PATCH 1/1] vas: vas_window_init_dbgdir: fix order of cleanup.

[Sukadev Bhattiprolu]

Fix the order of cleanup to ensure we free the name buffer in case
of an error creating 'hvwc' or 'info' files.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-debug.c | 8 
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
index ca22f1e..b4de4c6 100644
--- a/arch/powerpc/platforms/powernv/vas-debug.c
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -166,13 +166,13 @@ void vas_window_init_dbgdir(struct vas_window *window)
 
return;
 
-free_name:
-   kfree(window->dbgname);
-   window->dbgname = NULL;
-
 remove_dir:
debugfs_remove_recursive(window->dbgdir);
window->dbgdir = NULL;
+
+free_name:
+   kfree(window->dbgname);
+   window->dbgname = NULL;
 }
 
 void vas_instance_init_dbgdir(struct vas_instance *vinst)
-- 
2.7.4

[PATCH 1/1]: powerpc: block interrupts when updating TIDR

[Sukadev Bhattiprolu]

From: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Date: Tue, 28 Nov 2017 13:39:43 -0600
Subject: [PATCH 1/1]: powerpc: block interrupts when updating TIDR

clear_thread_tidr() is called in interrupt context as a part of delayed
put of the task structure (i.e as a part of timer interrupt). To prevent
a deadlock, block interrupts when holding vas_thread_id_lock to set/
clear TIDR for a task.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/process.c | 15 +--
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index bfdd783..aa8dbb9 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1509,14 +1509,15 @@ static int assign_thread_tidr(void)
 {
int index;
int err;
+   unsigned long flags;
 
 again:
if (!ida_pre_get(_thread_ida, GFP_KERNEL))
return -ENOMEM;
 
-   spin_lock(_thread_id_lock);
+   spin_lock_irqsave(_thread_id_lock, flags);
err = ida_get_new_above(_thread_ida, 1, );
-   spin_unlock(_thread_id_lock);
+   spin_unlock_irqrestore(_thread_id_lock, flags);
 
if (err == -EAGAIN)
goto again;
@@ -1524,9 +1525,9 @@ static int assign_thread_tidr(void)
return err;
 
if (index > MAX_THREAD_CONTEXT) {
-   spin_lock(_thread_id_lock);
+   spin_lock_irqsave(_thread_id_lock, flags);
ida_remove(_thread_ida, index);
-   spin_unlock(_thread_id_lock);
+   spin_unlock_irqrestore(_thread_id_lock, flags);
return -ENOMEM;
}
 
@@ -1535,9 +1536,11 @@ static int assign_thread_tidr(void)
 
 static void free_thread_tidr(int id)
 {
-   spin_lock(_thread_id_lock);
+   unsigned long flags;
+
+   spin_lock_irqsave(_thread_id_lock, flags);
ida_remove(_thread_ida, id);
-   spin_unlock(_thread_id_lock);
+   spin_unlock_irqrestore(_thread_id_lock, flags);
 }
 
 /*
-- 
2.7.4

[PATCH 1/1]: powerpc: block interrupts when updating TIDR

[Sukadev Bhattiprolu]

From: Sukadev Bhattiprolu 
Date: Tue, 28 Nov 2017 13:39:43 -0600
Subject: [PATCH 1/1]: powerpc: block interrupts when updating TIDR

clear_thread_tidr() is called in interrupt context as a part of delayed
put of the task structure (i.e as a part of timer interrupt). To prevent
a deadlock, block interrupts when holding vas_thread_id_lock to set/
clear TIDR for a task.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/kernel/process.c | 15 +--
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index bfdd783..aa8dbb9 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1509,14 +1509,15 @@ static int assign_thread_tidr(void)
 {
int index;
int err;
+   unsigned long flags;
 
 again:
if (!ida_pre_get(_thread_ida, GFP_KERNEL))
return -ENOMEM;
 
-   spin_lock(_thread_id_lock);
+   spin_lock_irqsave(_thread_id_lock, flags);
err = ida_get_new_above(_thread_ida, 1, );
-   spin_unlock(_thread_id_lock);
+   spin_unlock_irqrestore(_thread_id_lock, flags);
 
if (err == -EAGAIN)
goto again;
@@ -1524,9 +1525,9 @@ static int assign_thread_tidr(void)
return err;
 
if (index > MAX_THREAD_CONTEXT) {
-   spin_lock(_thread_id_lock);
+   spin_lock_irqsave(_thread_id_lock, flags);
ida_remove(_thread_ida, index);
-   spin_unlock(_thread_id_lock);
+   spin_unlock_irqrestore(_thread_id_lock, flags);
return -ENOMEM;
}
 
@@ -1535,9 +1536,11 @@ static int assign_thread_tidr(void)
 
 static void free_thread_tidr(int id)
 {
-   spin_lock(_thread_id_lock);
+   unsigned long flags;
+
+   spin_lock_irqsave(_thread_id_lock, flags);
ida_remove(_thread_ida, id);
-   spin_unlock(_thread_id_lock);
+   spin_unlock_irqrestore(_thread_id_lock, flags);
 }
 
 /*
-- 
2.7.4

[PATCH] powerpc/vas, export chip_to_vas_id()

[Sukadev Bhattiprolu]

>From 958f8db089f4b89407fc4b89bccd3eaef585aa96 Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Date: Mon, 20 Nov 2017 12:53:15 -0600
Subject: [PATCH 1/1] powerpc/vas, export chip_to_vas_id()

Export the symbol chip_to_vas_id() to fix a build failure when
CONFIG_CRYPTO_DEV_NX_COMPRESS_POWERNV=m.

Reported-by: Haren Myneni <hb...@us.ibm.com>
Reported-by: Josh Boyer <jwbo...@fedoraproject.org>
Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---

This was broken by the patch https://lkml.org/lkml/2017/11/7/915.

---
 arch/powerpc/platforms/powernv/vas.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index c488621..aebbe95 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -135,6 +135,7 @@ int chip_to_vas_id(int chipid)
}
return -1;
 }
+EXPORT_SYMBOL(chip_to_vas_id);
 
 static int vas_probe(struct platform_device *pdev)
 {
-- 
2.7.4

[PATCH] powerpc/vas, export chip_to_vas_id()

[Sukadev Bhattiprolu]

>From 958f8db089f4b89407fc4b89bccd3eaef585aa96 Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu 
Date: Mon, 20 Nov 2017 12:53:15 -0600
Subject: [PATCH 1/1] powerpc/vas, export chip_to_vas_id()

Export the symbol chip_to_vas_id() to fix a build failure when
CONFIG_CRYPTO_DEV_NX_COMPRESS_POWERNV=m.

Reported-by: Haren Myneni 
Reported-by: Josh Boyer 
Signed-off-by: Sukadev Bhattiprolu 
---

This was broken by the patch https://lkml.org/lkml/2017/11/7/915.

---
 arch/powerpc/platforms/powernv/vas.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index c488621..aebbe95 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -135,6 +135,7 @@ int chip_to_vas_id(int chipid)
}
return -1;
 }
+EXPORT_SYMBOL(chip_to_vas_id);
 
 static int vas_probe(struct platform_device *pdev)
 {
-- 
2.7.4

[tip:perf/core] perf vendor events powerpc: Update POWER9 events

[tip-bot for Sukadev Bhattiprolu]

Commit-ID:  e795dd42b716ff36ebaa5384fd1be8458d6c9c34
Gitweb: https://git.kernel.org/tip/e795dd42b716ff36ebaa5384fd1be8458d6c9c34
Author: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
AuthorDate: Wed, 8 Nov 2017 18:42:03 -0500
Committer:  Arnaldo Carvalho de Melo <a...@redhat.com>
CommitDate: Thu, 16 Nov 2017 14:49:54 -0300

perf vendor events powerpc: Update POWER9 events

The POWER9 hardware has dropped support for several events, added
a few new events and changed the category for a couple of events.

Update the POWER9 events in Linux to reflect these changes.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Cc: Jiri Olsa <jo...@redhat.com>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Madhavan Srinivasan <ma...@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20171108201938.ga10...@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com>
---
 .../perf/pmu-events/arch/powerpc/power9/cache.json |   5 -
 .../pmu-events/arch/powerpc/power9/frontend.json   |   7 +-
 .../pmu-events/arch/powerpc/power9/marked.json |  27 +-
 .../perf/pmu-events/arch/powerpc/power9/other.json | 276 ++---
 .../pmu-events/arch/powerpc/power9/pipeline.json   |  14 +-
 tools/perf/pmu-events/arch/powerpc/power9/pmc.json |   2 +-
 .../arch/powerpc/power9/translation.json   |   5 -
 7 files changed, 88 insertions(+), 248 deletions(-)

diff --git a/tools/perf/pmu-events/arch/powerpc/power9/cache.json 
b/tools/perf/pmu-events/arch/powerpc/power9/cache.json
index 18f6645..7945c51 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/cache.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/cache.json
@@ -125,11 +125,6 @@
 "BriefDescription": "Finish stall because the NTF instruction was a larx 
waiting to be satisfied"
   },
   {,
-"EventCode": "0x3006C",
-"EventName": "PM_RUN_CYC_SMT2_MODE",
-"BriefDescription": "Cycles in which this thread's run latch is set and 
the core is in SMT2 mode"
-  },
-  {,
 "EventCode": "0x1C058",
 "EventName": "PM_DTLB_MISS_16G",
 "BriefDescription": "Data TLB Miss page size 16G"
diff --git a/tools/perf/pmu-events/arch/powerpc/power9/frontend.json 
b/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
index c63a919..bd8361b 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
@@ -1,10 +1,5 @@
 [
   {,
-"EventCode": "0x3E15C",
-"EventName": "PM_MRK_L2_TM_ST_ABORT_SISTER",
-"BriefDescription": "TM marked store abort for this thread"
-  },
-  {,
 "EventCode": "0x25044",
 "EventName": "PM_IPTEG_FROM_L31_MOD",
 "BriefDescription": "A Page Table Entry was loaded into the TLB with 
Modified (M) data from another core's L3 on the same chip due to a instruction 
side request"
@@ -369,4 +364,4 @@
 "EventName": "PM_IPTEG_FROM_L31_ECO_MOD",
 "BriefDescription": "A Page Table Entry was loaded into the TLB with 
Modified (M) data from another core's ECO L3 on the same chip due to a 
instruction side request"
   }
-]
+]
\ No newline at end of file
diff --git a/tools/perf/pmu-events/arch/powerpc/power9/marked.json 
b/tools/perf/pmu-events/arch/powerpc/power9/marked.json
index b9df54f..22f9f32 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/marked.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/marked.json
@@ -1,10 +1,5 @@
 [
   {,
-"EventCode": "0x3C052",
-"EventName": "PM_DATA_SYS_PUMP_MPRED",
-"BriefDescription": "Final Pump Scope (system) mispredicted. Either the 
original scope was too small (Chip/Group) or the original scope was System and 
it should have been smaller. Counts for a demand load"
-  },
-  {,
 "EventCode": "0x3013E",
 "EventName": "PM_MRK_STALL_CMPLU_CYC",
 "BriefDescription": "Number of cycles the marked instruction is 
experiencing a stall while it is next to complete (NTC)"
@@ -255,6 +250,11 @@
 "BriefDescription": "A Page Directory Entry was reloaded to a level 1 page 
walk cache from the core's L3 data cache"
   },
   {,
+"EventCode": "0x3C052",
+"EventName": "PM_DATA_SYS_PUMP_MPRED",
+"BriefDescription": "Final Pump Scope (system) mispredicted. Either the 
original scope was too small (Chip/Group) or the original scope was System and 
it should have been smaller. Counts for a demand load"
+  },
+  {,
 "EventCode": "0x4D142",
 "EventName": "PM_MRK_DATA_F

[tip:perf/core] perf vendor events powerpc: Update POWER9 events

[tip-bot for Sukadev Bhattiprolu]

Commit-ID:  e795dd42b716ff36ebaa5384fd1be8458d6c9c34
Gitweb: https://git.kernel.org/tip/e795dd42b716ff36ebaa5384fd1be8458d6c9c34
Author: Sukadev Bhattiprolu 
AuthorDate: Wed, 8 Nov 2017 18:42:03 -0500
Committer:  Arnaldo Carvalho de Melo 
CommitDate: Thu, 16 Nov 2017 14:49:54 -0300

perf vendor events powerpc: Update POWER9 events

The POWER9 hardware has dropped support for several events, added
a few new events and changed the category for a couple of events.

Update the POWER9 events in Linux to reflect these changes.

Signed-off-by: Sukadev Bhattiprolu 
Cc: Jiri Olsa 
Cc: Michael Ellerman 
Cc: Madhavan Srinivasan 
Link: http://lkml.kernel.org/r/20171108201938.ga10...@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo 
---
 .../perf/pmu-events/arch/powerpc/power9/cache.json |   5 -
 .../pmu-events/arch/powerpc/power9/frontend.json   |   7 +-
 .../pmu-events/arch/powerpc/power9/marked.json |  27 +-
 .../perf/pmu-events/arch/powerpc/power9/other.json | 276 ++---
 .../pmu-events/arch/powerpc/power9/pipeline.json   |  14 +-
 tools/perf/pmu-events/arch/powerpc/power9/pmc.json |   2 +-
 .../arch/powerpc/power9/translation.json   |   5 -
 7 files changed, 88 insertions(+), 248 deletions(-)

diff --git a/tools/perf/pmu-events/arch/powerpc/power9/cache.json 
b/tools/perf/pmu-events/arch/powerpc/power9/cache.json
index 18f6645..7945c51 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/cache.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/cache.json
@@ -125,11 +125,6 @@
 "BriefDescription": "Finish stall because the NTF instruction was a larx 
waiting to be satisfied"
   },
   {,
-"EventCode": "0x3006C",
-"EventName": "PM_RUN_CYC_SMT2_MODE",
-"BriefDescription": "Cycles in which this thread's run latch is set and 
the core is in SMT2 mode"
-  },
-  {,
 "EventCode": "0x1C058",
 "EventName": "PM_DTLB_MISS_16G",
 "BriefDescription": "Data TLB Miss page size 16G"
diff --git a/tools/perf/pmu-events/arch/powerpc/power9/frontend.json 
b/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
index c63a919..bd8361b 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/frontend.json
@@ -1,10 +1,5 @@
 [
   {,
-"EventCode": "0x3E15C",
-"EventName": "PM_MRK_L2_TM_ST_ABORT_SISTER",
-"BriefDescription": "TM marked store abort for this thread"
-  },
-  {,
 "EventCode": "0x25044",
 "EventName": "PM_IPTEG_FROM_L31_MOD",
 "BriefDescription": "A Page Table Entry was loaded into the TLB with 
Modified (M) data from another core's L3 on the same chip due to a instruction 
side request"
@@ -369,4 +364,4 @@
 "EventName": "PM_IPTEG_FROM_L31_ECO_MOD",
 "BriefDescription": "A Page Table Entry was loaded into the TLB with 
Modified (M) data from another core's ECO L3 on the same chip due to a 
instruction side request"
   }
-]
+]
\ No newline at end of file
diff --git a/tools/perf/pmu-events/arch/powerpc/power9/marked.json 
b/tools/perf/pmu-events/arch/powerpc/power9/marked.json
index b9df54f..22f9f32 100644
--- a/tools/perf/pmu-events/arch/powerpc/power9/marked.json
+++ b/tools/perf/pmu-events/arch/powerpc/power9/marked.json
@@ -1,10 +1,5 @@
 [
   {,
-"EventCode": "0x3C052",
-"EventName": "PM_DATA_SYS_PUMP_MPRED",
-"BriefDescription": "Final Pump Scope (system) mispredicted. Either the 
original scope was too small (Chip/Group) or the original scope was System and 
it should have been smaller. Counts for a demand load"
-  },
-  {,
 "EventCode": "0x3013E",
 "EventName": "PM_MRK_STALL_CMPLU_CYC",
 "BriefDescription": "Number of cycles the marked instruction is 
experiencing a stall while it is next to complete (NTC)"
@@ -255,6 +250,11 @@
 "BriefDescription": "A Page Directory Entry was reloaded to a level 1 page 
walk cache from the core's L3 data cache"
   },
   {,
+"EventCode": "0x3C052",
+"EventName": "PM_DATA_SYS_PUMP_MPRED",
+"BriefDescription": "Final Pump Scope (system) mispredicted. Either the 
original scope was too small (Chip/Group) or the original scope was System and 
it should have been smaller. Counts for a demand load"
+  },
+  {,
 "EventCode": "0x4D142",
 "EventName": "PM_MRK_DATA_FROM_L3",
 "BriefDescription": "The processor's data cache was reloaded from local 
core's L3 due to a marked load"
@@ -435,21 +435,6 @@
 "BriefDe

[GIT PULL] Please pull JSON files for POWR9 PMU events

[Sukadev Bhattiprolu]

Hi Arnaldo,

Please pull an update to the JSON files for POWER9 PMU events.

The following changes since commit 148b43a3540bf25875bb5ab695a446950dc8d559:

  tools headers: Synchronize kernel ABI headers wrt SPDX tags (2017-11-07 
13:41:35 -0300)

are available in the git repository at:

  https://github.com/sukadev/linux p9-json-v4

for you to fetch changes up to 4afb062d7d306bf56dbae9b5291e3515ccfede4c:

  perf vendor events powerpc: Update POWER9 events (2017-11-08 18:42:03 -0500)


Sukadev Bhattiprolu (1):
  perf vendor events powerpc: Update POWER9 events

 .../perf/pmu-events/arch/powerpc/power9/cache.json |   5 -
 .../pmu-events/arch/powerpc/power9/frontend.json   |   7 +-
 .../pmu-events/arch/powerpc/power9/marked.json |  27 +-
 .../perf/pmu-events/arch/powerpc/power9/other.json | 276 ++---
 .../pmu-events/arch/powerpc/power9/pipeline.json   |  14 +-
 tools/perf/pmu-events/arch/powerpc/power9/pmc.json |   2 +-
 .../arch/powerpc/power9/translation.json   |   5 -
 7 files changed, 88 insertions(+), 248 deletions(-)

[GIT PULL] Please pull JSON files for POWR9 PMU events

[Sukadev Bhattiprolu]

Hi Arnaldo,

Please pull an update to the JSON files for POWER9 PMU events.

The following changes since commit 148b43a3540bf25875bb5ab695a446950dc8d559:

  tools headers: Synchronize kernel ABI headers wrt SPDX tags (2017-11-07 
13:41:35 -0300)

are available in the git repository at:

  https://github.com/sukadev/linux p9-json-v4

for you to fetch changes up to 4afb062d7d306bf56dbae9b5291e3515ccfede4c:

  perf vendor events powerpc: Update POWER9 events (2017-11-08 18:42:03 -0500)


Sukadev Bhattiprolu (1):
  perf vendor events powerpc: Update POWER9 events

 .../perf/pmu-events/arch/powerpc/power9/cache.json |   5 -
 .../pmu-events/arch/powerpc/power9/frontend.json   |   7 +-
 .../pmu-events/arch/powerpc/power9/marked.json |  27 +-
 .../perf/pmu-events/arch/powerpc/power9/other.json | 276 ++---
 .../pmu-events/arch/powerpc/power9/pipeline.json   |  14 +-
 tools/perf/pmu-events/arch/powerpc/power9/pmc.json |   2 +-
 .../arch/powerpc/power9/translation.json   |   5 -
 7 files changed, 88 insertions(+), 248 deletions(-)

[PATCH v3 03/18] powerpc/vas: Cleanup some debug code

[Sukadev Bhattiprolu]

Clean up vas.h and the debug code around ifdef vas_debug.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>

---
Changelog[v3]
- Minor tweak to a debug message
---
 arch/powerpc/platforms/powernv/vas-window.c |  8 +++--
 arch/powerpc/platforms/powernv/vas.h| 54 ++---
 2 files changed, 17 insertions(+), 45 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index a2fe120..67ffc5d 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -726,7 +726,10 @@ static void init_winctx_for_rxwin(struct vas_window *rxwin,
 static bool rx_win_args_valid(enum vas_cop_type cop,
struct vas_rx_win_attr *attr)
 {
-   dump_rx_win_attr(attr);
+   pr_debug("Rxattr: fault %d, notify %d, intr %d, early %d, fifo %d\n",
+   attr->fault_win, attr->notify_disable,
+   attr->intr_disable, attr->notify_early,
+   attr->rx_fifo_size);
 
if (cop >= VAS_COP_TYPE_MAX)
return false;
@@ -1050,7 +1053,8 @@ int vas_paste_crb(struct vas_window *txwin, int offset, 
bool re)
else
rc = -EINVAL;
 
-   print_fifo_msg_count(txwin);
+   pr_debug("Txwin #%d: Msg count %llu\n", txwin->winid,
+   read_hvwc_reg(txwin, VREG(LRFIFO_PUSH)));
 
return rc;
 }
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index fea0de4..63e8e03 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -259,6 +259,16 @@
 #define VAS_NX_UTIL_ADDER  PPC_BITMASK(32, 63)
 
 /*
+ * VREG(x):
+ * Expand a register's short name (eg: LPID) into two parameters:
+ * - the register's short name in string form ("LPID"), and
+ * - the name of the macro (eg: VAS_LPID_OFFSET), defining the
+ *   register's offset in the window context
+ */
+#define VREG_SFX(n, s) __stringify(n), VAS_##n##s
+#define VREG(r)VREG_SFX(r, _OFFSET)
+
+/*
  * Local Notify Scope Control Register. (Receive windows only).
  */
 enum vas_notify_scope {
@@ -385,43 +395,15 @@ struct vas_winctx {
 
 extern struct vas_instance *find_vas_instance(int vasid);
 
-/*
- * VREG(x):
- * Expand a register's short name (eg: LPID) into two parameters:
- * - the register's short name in string form ("LPID"), and
- * - the name of the macro (eg: VAS_LPID_OFFSET), defining the
- *   register's offset in the window context
- */
-#define VREG_SFX(n, s) __stringify(n), VAS_##n##s
-#define VREG(r)VREG_SFX(r, _OFFSET)
-
-#ifdef vas_debug
-static inline void dump_rx_win_attr(struct vas_rx_win_attr *attr)
-{
-   pr_err("fault %d, notify %d, intr %d early %d\n",
-   attr->fault_win, attr->notify_disable,
-   attr->intr_disable, attr->notify_early);
-
-   pr_err("rx_fifo_size %d, max value %d\n",
-   attr->rx_fifo_size, VAS_RX_FIFO_SIZE_MAX);
-}
-
 static inline void vas_log_write(struct vas_window *win, char *name,
void *regptr, u64 val)
 {
if (val)
-   pr_err("%swin #%d: %s reg %p, val 0x%016llx\n",
+   pr_debug("%swin #%d: %s reg %p, val 0x%016llx\n",
win->tx_win ? "Tx" : "Rx", win->winid, name,
regptr, val);
 }
 
-#else  /* vas_debug */
-
-#define vas_log_write(win, name, reg, val)
-#define dump_rx_win_attr(attr)
-
-#endif /* vas_debug */
-
 static inline void write_uwc_reg(struct vas_window *win, char *name,
s32 reg, u64 val)
 {
@@ -450,18 +432,4 @@ static inline u64 read_hvwc_reg(struct vas_window *win,
return in_be64(win->hvwc_map+reg);
 }
 
-#ifdef vas_debug
-
-static void print_fifo_msg_count(struct vas_window *txwin)
-{
-   uint64_t read_hvwc_reg(struct vas_window *w, char *n, uint64_t o);
-   pr_devel("Winid %d, Msg count %llu\n", txwin->winid,
-   (uint64_t)read_hvwc_reg(txwin, VREG(LRFIFO_PUSH)));
-}
-#else  /* vas_debug */
-
-#define print_fifo_msg_count(window)
-
-#endif /* vas_debug */
-
 #endif /* _VAS_H */
-- 
2.7.4

[PATCH v3 03/18] powerpc/vas: Cleanup some debug code

[Sukadev Bhattiprolu]

Clean up vas.h and the debug code around ifdef vas_debug.

Signed-off-by: Sukadev Bhattiprolu 

---
Changelog[v3]
- Minor tweak to a debug message
---
 arch/powerpc/platforms/powernv/vas-window.c |  8 +++--
 arch/powerpc/platforms/powernv/vas.h| 54 ++---
 2 files changed, 17 insertions(+), 45 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index a2fe120..67ffc5d 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -726,7 +726,10 @@ static void init_winctx_for_rxwin(struct vas_window *rxwin,
 static bool rx_win_args_valid(enum vas_cop_type cop,
struct vas_rx_win_attr *attr)
 {
-   dump_rx_win_attr(attr);
+   pr_debug("Rxattr: fault %d, notify %d, intr %d, early %d, fifo %d\n",
+   attr->fault_win, attr->notify_disable,
+   attr->intr_disable, attr->notify_early,
+   attr->rx_fifo_size);
 
if (cop >= VAS_COP_TYPE_MAX)
return false;
@@ -1050,7 +1053,8 @@ int vas_paste_crb(struct vas_window *txwin, int offset, 
bool re)
else
rc = -EINVAL;
 
-   print_fifo_msg_count(txwin);
+   pr_debug("Txwin #%d: Msg count %llu\n", txwin->winid,
+   read_hvwc_reg(txwin, VREG(LRFIFO_PUSH)));
 
return rc;
 }
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index fea0de4..63e8e03 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -259,6 +259,16 @@
 #define VAS_NX_UTIL_ADDER  PPC_BITMASK(32, 63)
 
 /*
+ * VREG(x):
+ * Expand a register's short name (eg: LPID) into two parameters:
+ * - the register's short name in string form ("LPID"), and
+ * - the name of the macro (eg: VAS_LPID_OFFSET), defining the
+ *   register's offset in the window context
+ */
+#define VREG_SFX(n, s) __stringify(n), VAS_##n##s
+#define VREG(r)VREG_SFX(r, _OFFSET)
+
+/*
  * Local Notify Scope Control Register. (Receive windows only).
  */
 enum vas_notify_scope {
@@ -385,43 +395,15 @@ struct vas_winctx {
 
 extern struct vas_instance *find_vas_instance(int vasid);
 
-/*
- * VREG(x):
- * Expand a register's short name (eg: LPID) into two parameters:
- * - the register's short name in string form ("LPID"), and
- * - the name of the macro (eg: VAS_LPID_OFFSET), defining the
- *   register's offset in the window context
- */
-#define VREG_SFX(n, s) __stringify(n), VAS_##n##s
-#define VREG(r)VREG_SFX(r, _OFFSET)
-
-#ifdef vas_debug
-static inline void dump_rx_win_attr(struct vas_rx_win_attr *attr)
-{
-   pr_err("fault %d, notify %d, intr %d early %d\n",
-   attr->fault_win, attr->notify_disable,
-   attr->intr_disable, attr->notify_early);
-
-   pr_err("rx_fifo_size %d, max value %d\n",
-   attr->rx_fifo_size, VAS_RX_FIFO_SIZE_MAX);
-}
-
 static inline void vas_log_write(struct vas_window *win, char *name,
void *regptr, u64 val)
 {
if (val)
-   pr_err("%swin #%d: %s reg %p, val 0x%016llx\n",
+   pr_debug("%swin #%d: %s reg %p, val 0x%016llx\n",
win->tx_win ? "Tx" : "Rx", win->winid, name,
regptr, val);
 }
 
-#else  /* vas_debug */
-
-#define vas_log_write(win, name, reg, val)
-#define dump_rx_win_attr(attr)
-
-#endif /* vas_debug */
-
 static inline void write_uwc_reg(struct vas_window *win, char *name,
s32 reg, u64 val)
 {
@@ -450,18 +432,4 @@ static inline u64 read_hvwc_reg(struct vas_window *win,
return in_be64(win->hvwc_map+reg);
 }
 
-#ifdef vas_debug
-
-static void print_fifo_msg_count(struct vas_window *txwin)
-{
-   uint64_t read_hvwc_reg(struct vas_window *w, char *n, uint64_t o);
-   pr_devel("Winid %d, Msg count %llu\n", txwin->winid,
-   (uint64_t)read_hvwc_reg(txwin, VREG(LRFIFO_PUSH)));
-}
-#else  /* vas_debug */
-
-#define print_fifo_msg_count(window)
-
-#endif /* vas_debug */
-
 #endif /* _VAS_H */
-- 
2.7.4

[PATCH v3 08/18] powerpc/vas: poll for return of window credits

[Sukadev Bhattiprolu]

Normally, the NX driver waits for the CRBs to be processed before closing
the window. But it is better to ensure that the credits are returned before
the window gets reassigned later.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 45 +
 1 file changed, 45 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index a59a187..23c13a7 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1063,6 +1063,49 @@ int vas_paste_crb(struct vas_window *txwin, int offset, 
bool re)
 EXPORT_SYMBOL_GPL(vas_paste_crb);
 
 /*
+ * If credit checking is enabled for this window, poll for the return
+ * of window credits (i.e for NX engines to process any outstanding CRBs).
+ * Since NX-842 waits for the CRBs to be processed before closing the
+ * window, we should not have to wait for too long.
+ *
+ * TODO: We retry in 10ms intervals now. We could/should probably peek at
+ * the VAS_LRFIFO_PUSH_OFFSET register to get an estimate of pending
+ * CRBs on the FIFO and compute the delay dynamically on each retry.
+ * But that is not really needed until we support NX-GZIP access from
+ * user space. (NX-842 driver waits for CSB and Fast thread-wakeup
+ * doesn't use credit checking).
+ */
+static void poll_window_credits(struct vas_window *window)
+{
+   u64 val;
+   int creds, mode;
+
+   val = read_hvwc_reg(window, VREG(WINCTL));
+   if (window->tx_win)
+   mode = GET_FIELD(VAS_WINCTL_TX_WCRED_MODE, val);
+   else
+   mode = GET_FIELD(VAS_WINCTL_RX_WCRED_MODE, val);
+
+   if (!mode)
+   return;
+retry:
+   if (window->tx_win) {
+   val = read_hvwc_reg(window, VREG(TX_WCRED));
+   creds = GET_FIELD(VAS_TX_WCRED, val);
+   } else {
+   val = read_hvwc_reg(window, VREG(LRX_WCRED));
+   creds = GET_FIELD(VAS_LRX_WCRED, val);
+   }
+
+   if (creds < window->wcreds_max) {
+   val = 0;
+   set_current_state(TASK_UNINTERRUPTIBLE);
+   schedule_timeout(msecs_to_jiffies(10));
+   goto retry;
+   }
+}
+
+/*
  * Wait for the window to go to "not-busy" state. It should only take a
  * short time to queue a CRB, so window should not be busy for too long.
  * Trying 5ms intervals.
@@ -1149,6 +1192,8 @@ int vas_win_close(struct vas_window *window)
 
unpin_close_window(window);
 
+   poll_window_credits(window);
+
poll_window_castout(window);
 
/* if send window, drop reference to matching receive window */
-- 
2.7.4

[PATCH v3 04/18] powerpc/vas: Drop poll_window_cast_out().

[Sukadev Bhattiprolu]

Polling for window cast out is listed in the spec, but turns out that
it is not strictly necessary and slows down window close. Making it a
stub for now.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 34 ++---
 1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 67ffc5d..8ab8a82 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1079,25 +1079,25 @@ static void poll_window_busy_state(struct vas_window 
*window)
}
 }
 
+/*
+ * Have the hardware cast a window out of cache and wait for it to
+ * be completed.
+ *
+ * NOTE: It can take a relatively long time to cast the window context
+ * out of the cache. It is not strictly necessary to cast out if:
+ *
+ * - we clear the "Pin Window" bit (so hardware is free to evict)
+ *
+ * - we re-initialize the window context when it is reassigned.
+ *
+ * We do the former in vas_win_close() and latter in vas_win_open().
+ * So, ignoring the cast-out for now. We can add it as needed. If
+ * casting out becomes necessary we should consider offloading the
+ * job to a worker thread, so the window close can proceed quickly.
+ */
 static void poll_window_castout(struct vas_window *window)
 {
-   int cached;
-   u64 val;
-
-   /* Cast window context out of the cache */
-retry:
-   val = read_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL));
-   cached = GET_FIELD(VAS_WIN_CACHE_STATUS, val);
-   if (cached) {
-   val = 0ULL;
-   val = SET_FIELD(VAS_CASTOUT_REQ, val, 1);
-   val = SET_FIELD(VAS_PUSH_TO_MEM, val, 0);
-   write_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL), val);
-
-   set_current_state(TASK_UNINTERRUPTIBLE);
-   schedule_timeout(HZ);
-   goto retry;
-   }
+   /* stub for now */
 }
 
 /*
-- 
2.7.4

[PATCH v3 08/18] powerpc/vas: poll for return of window credits

[Sukadev Bhattiprolu]

Normally, the NX driver waits for the CRBs to be processed before closing
the window. But it is better to ensure that the credits are returned before
the window gets reassigned later.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-window.c | 45 +
 1 file changed, 45 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index a59a187..23c13a7 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1063,6 +1063,49 @@ int vas_paste_crb(struct vas_window *txwin, int offset, 
bool re)
 EXPORT_SYMBOL_GPL(vas_paste_crb);
 
 /*
+ * If credit checking is enabled for this window, poll for the return
+ * of window credits (i.e for NX engines to process any outstanding CRBs).
+ * Since NX-842 waits for the CRBs to be processed before closing the
+ * window, we should not have to wait for too long.
+ *
+ * TODO: We retry in 10ms intervals now. We could/should probably peek at
+ * the VAS_LRFIFO_PUSH_OFFSET register to get an estimate of pending
+ * CRBs on the FIFO and compute the delay dynamically on each retry.
+ * But that is not really needed until we support NX-GZIP access from
+ * user space. (NX-842 driver waits for CSB and Fast thread-wakeup
+ * doesn't use credit checking).
+ */
+static void poll_window_credits(struct vas_window *window)
+{
+   u64 val;
+   int creds, mode;
+
+   val = read_hvwc_reg(window, VREG(WINCTL));
+   if (window->tx_win)
+   mode = GET_FIELD(VAS_WINCTL_TX_WCRED_MODE, val);
+   else
+   mode = GET_FIELD(VAS_WINCTL_RX_WCRED_MODE, val);
+
+   if (!mode)
+   return;
+retry:
+   if (window->tx_win) {
+   val = read_hvwc_reg(window, VREG(TX_WCRED));
+   creds = GET_FIELD(VAS_TX_WCRED, val);
+   } else {
+   val = read_hvwc_reg(window, VREG(LRX_WCRED));
+   creds = GET_FIELD(VAS_LRX_WCRED, val);
+   }
+
+   if (creds < window->wcreds_max) {
+   val = 0;
+   set_current_state(TASK_UNINTERRUPTIBLE);
+   schedule_timeout(msecs_to_jiffies(10));
+   goto retry;
+   }
+}
+
+/*
  * Wait for the window to go to "not-busy" state. It should only take a
  * short time to queue a CRB, so window should not be busy for too long.
  * Trying 5ms intervals.
@@ -1149,6 +1192,8 @@ int vas_win_close(struct vas_window *window)
 
unpin_close_window(window);
 
+   poll_window_credits(window);
+
poll_window_castout(window);
 
/* if send window, drop reference to matching receive window */
-- 
2.7.4

[PATCH v3 04/18] powerpc/vas: Drop poll_window_cast_out().

[Sukadev Bhattiprolu]

Polling for window cast out is listed in the spec, but turns out that
it is not strictly necessary and slows down window close. Making it a
stub for now.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-window.c | 34 ++---
 1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 67ffc5d..8ab8a82 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1079,25 +1079,25 @@ static void poll_window_busy_state(struct vas_window 
*window)
}
 }
 
+/*
+ * Have the hardware cast a window out of cache and wait for it to
+ * be completed.
+ *
+ * NOTE: It can take a relatively long time to cast the window context
+ * out of the cache. It is not strictly necessary to cast out if:
+ *
+ * - we clear the "Pin Window" bit (so hardware is free to evict)
+ *
+ * - we re-initialize the window context when it is reassigned.
+ *
+ * We do the former in vas_win_close() and latter in vas_win_open().
+ * So, ignoring the cast-out for now. We can add it as needed. If
+ * casting out becomes necessary we should consider offloading the
+ * job to a worker thread, so the window close can proceed quickly.
+ */
 static void poll_window_castout(struct vas_window *window)
 {
-   int cached;
-   u64 val;
-
-   /* Cast window context out of the cache */
-retry:
-   val = read_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL));
-   cached = GET_FIELD(VAS_WIN_CACHE_STATUS, val);
-   if (cached) {
-   val = 0ULL;
-   val = SET_FIELD(VAS_CASTOUT_REQ, val, 1);
-   val = SET_FIELD(VAS_PUSH_TO_MEM, val, 0);
-   write_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL), val);
-
-   set_current_state(TASK_UNINTERRUPTIBLE);
-   schedule_timeout(HZ);
-   goto retry;
-   }
+   /* stub for now */
 }
 
 /*
-- 
2.7.4

[PATCH v3 07/18] powerpc/vas: Save configured window credits

[Sukadev Bhattiprolu]

Save the configured max window credits for a window in the vas_window
structure. We will need this when polling for return of window credits.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 6 --
 arch/powerpc/platforms/powernv/vas.h| 1 +
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 1422cdd..a59a187 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -674,7 +674,7 @@ static void init_winctx_for_rxwin(struct vas_window *rxwin,
 
winctx->rx_fifo = rxattr->rx_fifo;
winctx->rx_fifo_size = rxattr->rx_fifo_size;
-   winctx->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+   winctx->wcreds_max = rxwin->wcreds_max;
winctx->pin_win = rxattr->pin_win;
 
winctx->nx_win = rxattr->nx_win;
@@ -844,6 +844,7 @@ struct vas_window *vas_rx_win_open(int vasid, enum 
vas_cop_type cop,
rxwin->nx_win = rxattr->nx_win;
rxwin->user_win = rxattr->user_win;
rxwin->cop = cop;
+   rxwin->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
if (rxattr->user_win)
rxwin->pid = task_pid_vnr(current);
 
@@ -893,7 +894,7 @@ static void init_winctx_for_txwin(struct vas_window *txwin,
 */
memset(winctx, 0, sizeof(struct vas_winctx));
 
-   winctx->wcreds_max = txattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+   winctx->wcreds_max = txwin->wcreds_max;
 
winctx->user_win = txattr->user_win;
winctx->nx_win = txwin->rxwin->nx_win;
@@ -978,6 +979,7 @@ struct vas_window *vas_tx_win_open(int vasid, enum 
vas_cop_type cop,
txwin->nx_win = txwin->rxwin->nx_win;
txwin->pid = attr->pid;
txwin->user_win = attr->user_win;
+   txwin->wcreds_max = attr->wcreds_max ?: VAS_WCREDS_DEFAULT;
 
init_winctx_for_txwin(txwin, attr, );
 
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index 63e8e03..02d8a31 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -332,6 +332,7 @@ struct vas_window {
void *hvwc_map; /* HV window context */
void *uwc_map;  /* OS/User window context */
pid_t pid;  /* Linux process id of owner */
+   int wcreds_max; /* Window credits */
 
/* Fields applicable only to send windows */
void *paste_kaddr;
-- 
2.7.4

[PATCH v3 07/18] powerpc/vas: Save configured window credits

[Sukadev Bhattiprolu]

Save the configured max window credits for a window in the vas_window
structure. We will need this when polling for return of window credits.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-window.c | 6 --
 arch/powerpc/platforms/powernv/vas.h| 1 +
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 1422cdd..a59a187 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -674,7 +674,7 @@ static void init_winctx_for_rxwin(struct vas_window *rxwin,
 
winctx->rx_fifo = rxattr->rx_fifo;
winctx->rx_fifo_size = rxattr->rx_fifo_size;
-   winctx->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+   winctx->wcreds_max = rxwin->wcreds_max;
winctx->pin_win = rxattr->pin_win;
 
winctx->nx_win = rxattr->nx_win;
@@ -844,6 +844,7 @@ struct vas_window *vas_rx_win_open(int vasid, enum 
vas_cop_type cop,
rxwin->nx_win = rxattr->nx_win;
rxwin->user_win = rxattr->user_win;
rxwin->cop = cop;
+   rxwin->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
if (rxattr->user_win)
rxwin->pid = task_pid_vnr(current);
 
@@ -893,7 +894,7 @@ static void init_winctx_for_txwin(struct vas_window *txwin,
 */
memset(winctx, 0, sizeof(struct vas_winctx));
 
-   winctx->wcreds_max = txattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+   winctx->wcreds_max = txwin->wcreds_max;
 
winctx->user_win = txattr->user_win;
winctx->nx_win = txwin->rxwin->nx_win;
@@ -978,6 +979,7 @@ struct vas_window *vas_tx_win_open(int vasid, enum 
vas_cop_type cop,
txwin->nx_win = txwin->rxwin->nx_win;
txwin->pid = attr->pid;
txwin->user_win = attr->user_win;
+   txwin->wcreds_max = attr->wcreds_max ?: VAS_WCREDS_DEFAULT;
 
init_winctx_for_txwin(txwin, attr, );
 
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index 63e8e03..02d8a31 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -332,6 +332,7 @@ struct vas_window {
void *hvwc_map; /* HV window context */
void *uwc_map;  /* OS/User window context */
pid_t pid;  /* Linux process id of owner */
+   int wcreds_max; /* Window credits */
 
/* Fields applicable only to send windows */
void *paste_kaddr;
-- 
2.7.4

[PATCH v3 05/18] powerpc/vas: Use helper to unpin/close window

[Sukadev Bhattiprolu]

Use a helper to have the hardware unpin and mark a window closed.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 22 +++---
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 8ab8a82..95622a9 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1101,6 +1101,20 @@ static void poll_window_castout(struct vas_window 
*window)
 }
 
 /*
+ * Unpin and close a window so no new requests are accepted and the
+ * hardware can evict this window from cache if necessary.
+ */
+static void unpin_close_window(struct vas_window *window)
+{
+   u64 val;
+
+   val = read_hvwc_reg(window, VREG(WINCTL));
+   val = SET_FIELD(VAS_WINCTL_PIN, val, 0);
+   val = SET_FIELD(VAS_WINCTL_OPEN, val, 0);
+   write_hvwc_reg(window, VREG(WINCTL), val);
+}
+
+/*
  * Close a window.
  *
  * See Section 1.12.1 of VAS workbook v1.05 for details on closing window:
@@ -1114,8 +1128,6 @@ static void poll_window_castout(struct vas_window *window)
  */
 int vas_win_close(struct vas_window *window)
 {
-   u64 val;
-
if (!window)
return 0;
 
@@ -1131,11 +1143,7 @@ int vas_win_close(struct vas_window *window)
 
poll_window_busy_state(window);
 
-   /* Unpin window from cache and close it */
-   val = read_hvwc_reg(window, VREG(WINCTL));
-   val = SET_FIELD(VAS_WINCTL_PIN, val, 0);
-   val = SET_FIELD(VAS_WINCTL_OPEN, val, 0);
-   write_hvwc_reg(window, VREG(WINCTL), val);
+   unpin_close_window(window);
 
poll_window_castout(window);
 
-- 
2.7.4

[PATCH v3 05/18] powerpc/vas: Use helper to unpin/close window

[Sukadev Bhattiprolu]

Use a helper to have the hardware unpin and mark a window closed.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-window.c | 22 +++---
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 8ab8a82..95622a9 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1101,6 +1101,20 @@ static void poll_window_castout(struct vas_window 
*window)
 }
 
 /*
+ * Unpin and close a window so no new requests are accepted and the
+ * hardware can evict this window from cache if necessary.
+ */
+static void unpin_close_window(struct vas_window *window)
+{
+   u64 val;
+
+   val = read_hvwc_reg(window, VREG(WINCTL));
+   val = SET_FIELD(VAS_WINCTL_PIN, val, 0);
+   val = SET_FIELD(VAS_WINCTL_OPEN, val, 0);
+   write_hvwc_reg(window, VREG(WINCTL), val);
+}
+
+/*
  * Close a window.
  *
  * See Section 1.12.1 of VAS workbook v1.05 for details on closing window:
@@ -1114,8 +1128,6 @@ static void poll_window_castout(struct vas_window *window)
  */
 int vas_win_close(struct vas_window *window)
 {
-   u64 val;
-
if (!window)
return 0;
 
@@ -1131,11 +1143,7 @@ int vas_win_close(struct vas_window *window)
 
poll_window_busy_state(window);
 
-   /* Unpin window from cache and close it */
-   val = read_hvwc_reg(window, VREG(WINCTL));
-   val = SET_FIELD(VAS_WINCTL_PIN, val, 0);
-   val = SET_FIELD(VAS_WINCTL_OPEN, val, 0);
-   write_hvwc_reg(window, VREG(WINCTL), val);
+   unpin_close_window(window);
 
poll_window_castout(window);
 
-- 
2.7.4

[PATCH v3 09/18] powerpc/vas: Create cpu to vas id mapping

[Sukadev Bhattiprolu]

Create a cpu to vasid mapping so callers can specify -1 instead of
trying to find a VAS id.

Changelog[v2]
[Michael Ellerman] Use per-cpu variables to simplify code.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas.c | 14 +-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index 565a487..abb7090 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -18,15 +18,18 @@
 #include 
 #include 
 #include 
+#include 
 
 #include "vas.h"
 
 static DEFINE_MUTEX(vas_mutex);
 static LIST_HEAD(vas_instances);
 
+static DEFINE_PER_CPU(int, cpu_vas_id);
+
 static int init_vas_instance(struct platform_device *pdev)
 {
-   int rc, vasid;
+   int rc, cpu, vasid;
struct resource *res;
struct vas_instance *vinst;
struct device_node *dn = pdev->dev.of_node;
@@ -74,6 +77,11 @@ static int init_vas_instance(struct platform_device *pdev)
"paste_win_id_shift 0x%llx\n", pdev->name, vasid,
vinst->paste_base_addr, vinst->paste_win_id_shift);
 
+   for_each_possible_cpu(cpu) {
+   if (cpu_to_chip_id(cpu) == of_get_ibm_chip_id(dn))
+   per_cpu(cpu_vas_id, cpu) = vasid;
+   }
+
mutex_lock(_mutex);
list_add(>node, _instances);
mutex_unlock(_mutex);
@@ -98,6 +106,10 @@ struct vas_instance *find_vas_instance(int vasid)
struct vas_instance *vinst;
 
mutex_lock(_mutex);
+
+   if (vasid == -1)
+   vasid = per_cpu(cpu_vas_id, smp_processor_id());
+
list_for_each(ent, _instances) {
vinst = list_entry(ent, struct vas_instance, node);
if (vinst->vas_id == vasid) {
-- 
2.7.4

[PATCH v3 12/18] powerpc: have copy depend on CONFIG_BOOK3S_64

[Sukadev Bhattiprolu]

Have the COPY/PASTE instructions depend on CONFIG_BOOK3S_64 rather than
CONFIG_PPC_STD_MMU_64.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/process.c | 6 +-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index a0c74bb..37ed60b 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1215,10 +1215,14 @@ struct task_struct *__switch_to(struct task_struct 
*prev,
batch = this_cpu_ptr(_tlb_batch);
batch->active = 1;
}
+#endif /* CONFIG_PPC_STD_MMU_64 */
 
if (current_thread_info()->task->thread.regs) {
+#ifdef CONFIG_PPC_STD_MMU_64
restore_math(current_thread_info()->task->thread.regs);
+#endif /* CONFIG_PPC_STD_MMU_64 */
 
+#ifdef CONFIG_PPC_BOOK3S_64
/*
 * The copy-paste buffer can only store into foreign real
 * addresses, so unprivileged processes can not see the
@@ -1237,8 +1241,8 @@ struct task_struct *__switch_to(struct task_struct *prev,
asm volatile(PPC_COPY(%0, %1)
: : "r"(dummy_copy_buffer), "r"(0));
}
+#endif /* CONFIG_PPC_BOOK3S_64 */
}
-#endif /* CONFIG_PPC_STD_MMU_64 */
 
return last;
 }
-- 
2.7.4

[PATCH v3 11/18] powerpc/vas: Export HVWC to debugfs

[Sukadev Bhattiprolu]

Export the VAS Window context information to debugfs.

We need to hold a mutex when closing the window to prevent a race
with the debugfs read(). Rather than introduce a per-instance mutex,
we use the global vas_mutex for now, since it is not heavily contended.

The window->cop field is only relevant to a receive window so we were
not setting it for a send window (which is is paired to a receive window
anyway). But to simplify reporting in debugfs, set the 'cop' field for the
send window also.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>

---
Changelog[v3]:
- [Michael Ellerman] Fix couple of unininitialized variables
---
 arch/powerpc/platforms/powernv/Makefile |   3 +-
 arch/powerpc/platforms/powernv/vas-debug.c  | 209 
 arch/powerpc/platforms/powernv/vas-window.c |  34 -
 arch/powerpc/platforms/powernv/vas.c|   6 +-
 arch/powerpc/platforms/powernv/vas.h|  14 ++
 5 files changed, 257 insertions(+), 9 deletions(-)
 create mode 100644 arch/powerpc/platforms/powernv/vas-debug.c

diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index 7a31c26..3732118 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -15,4 +15,5 @@ obj-$(CONFIG_TRACEPOINTS) += opal-tracepoints.o
 obj-$(CONFIG_OPAL_PRD) += opal-prd.o
 obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
 obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
-obj-$(CONFIG_PPC_VAS)  += vas.o vas-window.o
+obj-$(CONFIG_PPC_VAS)  += vas.o vas-window.o vas-debug.o
+obj-$(CONFIG_PPC_FTW)  += nx-ftw.o
diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
new file mode 100644
index 000..ca22f1e
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -0,0 +1,209 @@
+/*
+ * Copyright 2016-17 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "vas: " fmt
+
+#include 
+#include 
+#include 
+#include 
+#include "vas.h"
+
+static struct dentry *vas_debugfs;
+
+static char *cop_to_str(int cop)
+{
+   switch (cop) {
+   case VAS_COP_TYPE_FAULT:return "Fault";
+   case VAS_COP_TYPE_842:  return "NX-842 Normal Priority";
+   case VAS_COP_TYPE_842_HIPRI:return "NX-842 High Priority";
+   case VAS_COP_TYPE_GZIP: return "NX-GZIP Normal Priority";
+   case VAS_COP_TYPE_GZIP_HIPRI:   return "NX-GZIP High Priority";
+   case VAS_COP_TYPE_FTW:  return "Fast Thread-wakeup";
+   default:return "Unknown";
+   }
+}
+
+static int info_dbg_show(struct seq_file *s, void *private)
+{
+   struct vas_window *window = s->private;
+
+   mutex_lock(_mutex);
+
+   /* ensure window is not unmapped */
+   if (!window->hvwc_map)
+   goto unlock;
+
+   seq_printf(s, "Type: %s, %s\n", cop_to_str(window->cop),
+   window->tx_win ? "Send" : "Receive");
+   seq_printf(s, "Pid : %d\n", window->pid);
+
+unlock:
+   mutex_unlock(_mutex);
+   return 0;
+}
+
+static int info_dbg_open(struct inode *inode, struct file *file)
+{
+   return single_open(file, info_dbg_show, inode->i_private);
+}
+
+static const struct file_operations info_fops = {
+   .open   = info_dbg_open,
+   .read   = seq_read,
+   .llseek = seq_lseek,
+   .release= single_release,
+};
+
+static inline void print_reg(struct seq_file *s, struct vas_window *win,
+   char *name, u32 reg)
+{
+   seq_printf(s, "0x%016llx %s\n", read_hvwc_reg(win, name, reg), name);
+}
+
+static int hvwc_dbg_show(struct seq_file *s, void *private)
+{
+   struct vas_window *window = s->private;
+
+   mutex_lock(_mutex);
+
+   /* ensure window is not unmapped */
+   if (!window->hvwc_map)
+   goto unlock;
+
+   print_reg(s, window, VREG(LPID));
+   print_reg(s, window, VREG(PID));
+   print_reg(s, window, VREG(XLATE_MSR));
+   print_reg(s, window, VREG(XLATE_LPCR));
+   print_reg(s, window, VREG(XLATE_CTL));
+   print_reg(s, window, VREG(AMR));
+   print_reg(s, window, VREG(SEIDR));
+   print_reg(s, window, VREG(FAULT_TX_WIN));
+   print_reg(s, window, VREG(OSU_INTR_SRC_RA));
+   print_reg(s, window, VREG(HV_INTR_SRC_RA));
+   print_reg(s, window, VREG(PSWID));
+   print_reg(s, window, VREG(LFIFO_BAR));
+   print_reg(s, window, VREG(LDATA_STAMP_CTL));
+   print_reg(s, window, VREG(LDMA_CACHE_CTL));
+   

[PATCH v3 06/18] powerpc/vas: Reduce polling interval for busy state

[Sukadev Bhattiprolu]

A VAS window is normally in "busy" state for only a short duration.
Reduce the time we wait for the window to go to "not-busy" state to
speed-up vas_win_close() a bit.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 10 ++
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 95622a9..1422cdd 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1060,21 +1060,23 @@ int vas_paste_crb(struct vas_window *txwin, int offset, 
bool re)
 }
 EXPORT_SYMBOL_GPL(vas_paste_crb);
 
+/*
+ * Wait for the window to go to "not-busy" state. It should only take a
+ * short time to queue a CRB, so window should not be busy for too long.
+ * Trying 5ms intervals.
+ */
 static void poll_window_busy_state(struct vas_window *window)
 {
int busy;
u64 val;
 
 retry:
-   /*
-* Poll Window Busy flag
-*/
val = read_hvwc_reg(window, VREG(WIN_STATUS));
busy = GET_FIELD(VAS_WIN_BUSY, val);
if (busy) {
val = 0;
set_current_state(TASK_UNINTERRUPTIBLE);
-   schedule_timeout(HZ);
+   schedule_timeout(msecs_to_jiffies(5));
goto retry;
}
 }
-- 
2.7.4

[PATCH v3 09/18] powerpc/vas: Create cpu to vas id mapping

[Sukadev Bhattiprolu]

Create a cpu to vasid mapping so callers can specify -1 instead of
trying to find a VAS id.

Changelog[v2]
[Michael Ellerman] Use per-cpu variables to simplify code.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas.c | 14 +-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index 565a487..abb7090 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -18,15 +18,18 @@
 #include 
 #include 
 #include 
+#include 
 
 #include "vas.h"
 
 static DEFINE_MUTEX(vas_mutex);
 static LIST_HEAD(vas_instances);
 
+static DEFINE_PER_CPU(int, cpu_vas_id);
+
 static int init_vas_instance(struct platform_device *pdev)
 {
-   int rc, vasid;
+   int rc, cpu, vasid;
struct resource *res;
struct vas_instance *vinst;
struct device_node *dn = pdev->dev.of_node;
@@ -74,6 +77,11 @@ static int init_vas_instance(struct platform_device *pdev)
"paste_win_id_shift 0x%llx\n", pdev->name, vasid,
vinst->paste_base_addr, vinst->paste_win_id_shift);
 
+   for_each_possible_cpu(cpu) {
+   if (cpu_to_chip_id(cpu) == of_get_ibm_chip_id(dn))
+   per_cpu(cpu_vas_id, cpu) = vasid;
+   }
+
mutex_lock(_mutex);
list_add(>node, _instances);
mutex_unlock(_mutex);
@@ -98,6 +106,10 @@ struct vas_instance *find_vas_instance(int vasid)
struct vas_instance *vinst;
 
mutex_lock(_mutex);
+
+   if (vasid == -1)
+   vasid = per_cpu(cpu_vas_id, smp_processor_id());
+
list_for_each(ent, _instances) {
vinst = list_entry(ent, struct vas_instance, node);
if (vinst->vas_id == vasid) {
-- 
2.7.4

[PATCH v3 12/18] powerpc: have copy depend on CONFIG_BOOK3S_64

[Sukadev Bhattiprolu]

Have the COPY/PASTE instructions depend on CONFIG_BOOK3S_64 rather than
CONFIG_PPC_STD_MMU_64.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/kernel/process.c | 6 +-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index a0c74bb..37ed60b 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1215,10 +1215,14 @@ struct task_struct *__switch_to(struct task_struct 
*prev,
batch = this_cpu_ptr(_tlb_batch);
batch->active = 1;
}
+#endif /* CONFIG_PPC_STD_MMU_64 */
 
if (current_thread_info()->task->thread.regs) {
+#ifdef CONFIG_PPC_STD_MMU_64
restore_math(current_thread_info()->task->thread.regs);
+#endif /* CONFIG_PPC_STD_MMU_64 */
 
+#ifdef CONFIG_PPC_BOOK3S_64
/*
 * The copy-paste buffer can only store into foreign real
 * addresses, so unprivileged processes can not see the
@@ -1237,8 +1241,8 @@ struct task_struct *__switch_to(struct task_struct *prev,
asm volatile(PPC_COPY(%0, %1)
: : "r"(dummy_copy_buffer), "r"(0));
}
+#endif /* CONFIG_PPC_BOOK3S_64 */
}
-#endif /* CONFIG_PPC_STD_MMU_64 */
 
return last;
 }
-- 
2.7.4

[PATCH v3 11/18] powerpc/vas: Export HVWC to debugfs

[Sukadev Bhattiprolu]

Export the VAS Window context information to debugfs.

We need to hold a mutex when closing the window to prevent a race
with the debugfs read(). Rather than introduce a per-instance mutex,
we use the global vas_mutex for now, since it is not heavily contended.

The window->cop field is only relevant to a receive window so we were
not setting it for a send window (which is is paired to a receive window
anyway). But to simplify reporting in debugfs, set the 'cop' field for the
send window also.

Signed-off-by: Sukadev Bhattiprolu 

---
Changelog[v3]:
- [Michael Ellerman] Fix couple of unininitialized variables
---
 arch/powerpc/platforms/powernv/Makefile |   3 +-
 arch/powerpc/platforms/powernv/vas-debug.c  | 209 
 arch/powerpc/platforms/powernv/vas-window.c |  34 -
 arch/powerpc/platforms/powernv/vas.c|   6 +-
 arch/powerpc/platforms/powernv/vas.h|  14 ++
 5 files changed, 257 insertions(+), 9 deletions(-)
 create mode 100644 arch/powerpc/platforms/powernv/vas-debug.c

diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index 7a31c26..3732118 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -15,4 +15,5 @@ obj-$(CONFIG_TRACEPOINTS) += opal-tracepoints.o
 obj-$(CONFIG_OPAL_PRD) += opal-prd.o
 obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
 obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
-obj-$(CONFIG_PPC_VAS)  += vas.o vas-window.o
+obj-$(CONFIG_PPC_VAS)  += vas.o vas-window.o vas-debug.o
+obj-$(CONFIG_PPC_FTW)  += nx-ftw.o
diff --git a/arch/powerpc/platforms/powernv/vas-debug.c 
b/arch/powerpc/platforms/powernv/vas-debug.c
new file mode 100644
index 000..ca22f1e
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-debug.c
@@ -0,0 +1,209 @@
+/*
+ * Copyright 2016-17 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "vas: " fmt
+
+#include 
+#include 
+#include 
+#include 
+#include "vas.h"
+
+static struct dentry *vas_debugfs;
+
+static char *cop_to_str(int cop)
+{
+   switch (cop) {
+   case VAS_COP_TYPE_FAULT:return "Fault";
+   case VAS_COP_TYPE_842:  return "NX-842 Normal Priority";
+   case VAS_COP_TYPE_842_HIPRI:return "NX-842 High Priority";
+   case VAS_COP_TYPE_GZIP: return "NX-GZIP Normal Priority";
+   case VAS_COP_TYPE_GZIP_HIPRI:   return "NX-GZIP High Priority";
+   case VAS_COP_TYPE_FTW:  return "Fast Thread-wakeup";
+   default:return "Unknown";
+   }
+}
+
+static int info_dbg_show(struct seq_file *s, void *private)
+{
+   struct vas_window *window = s->private;
+
+   mutex_lock(_mutex);
+
+   /* ensure window is not unmapped */
+   if (!window->hvwc_map)
+   goto unlock;
+
+   seq_printf(s, "Type: %s, %s\n", cop_to_str(window->cop),
+   window->tx_win ? "Send" : "Receive");
+   seq_printf(s, "Pid : %d\n", window->pid);
+
+unlock:
+   mutex_unlock(_mutex);
+   return 0;
+}
+
+static int info_dbg_open(struct inode *inode, struct file *file)
+{
+   return single_open(file, info_dbg_show, inode->i_private);
+}
+
+static const struct file_operations info_fops = {
+   .open   = info_dbg_open,
+   .read   = seq_read,
+   .llseek = seq_lseek,
+   .release= single_release,
+};
+
+static inline void print_reg(struct seq_file *s, struct vas_window *win,
+   char *name, u32 reg)
+{
+   seq_printf(s, "0x%016llx %s\n", read_hvwc_reg(win, name, reg), name);
+}
+
+static int hvwc_dbg_show(struct seq_file *s, void *private)
+{
+   struct vas_window *window = s->private;
+
+   mutex_lock(_mutex);
+
+   /* ensure window is not unmapped */
+   if (!window->hvwc_map)
+   goto unlock;
+
+   print_reg(s, window, VREG(LPID));
+   print_reg(s, window, VREG(PID));
+   print_reg(s, window, VREG(XLATE_MSR));
+   print_reg(s, window, VREG(XLATE_LPCR));
+   print_reg(s, window, VREG(XLATE_CTL));
+   print_reg(s, window, VREG(AMR));
+   print_reg(s, window, VREG(SEIDR));
+   print_reg(s, window, VREG(FAULT_TX_WIN));
+   print_reg(s, window, VREG(OSU_INTR_SRC_RA));
+   print_reg(s, window, VREG(HV_INTR_SRC_RA));
+   print_reg(s, window, VREG(PSWID));
+   print_reg(s, window, VREG(LFIFO_BAR));
+   print_reg(s, window, VREG(LDATA_STAMP_CTL));
+   print_reg(s, window, VREG(LDMA_CACHE_CTL));
+   print_reg(s, window, VREG(

[PATCH v3 06/18] powerpc/vas: Reduce polling interval for busy state

[Sukadev Bhattiprolu]

A VAS window is normally in "busy" state for only a short duration.
Reduce the time we wait for the window to go to "not-busy" state to
speed-up vas_win_close() a bit.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-window.c | 10 ++
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 95622a9..1422cdd 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1060,21 +1060,23 @@ int vas_paste_crb(struct vas_window *txwin, int offset, 
bool re)
 }
 EXPORT_SYMBOL_GPL(vas_paste_crb);
 
+/*
+ * Wait for the window to go to "not-busy" state. It should only take a
+ * short time to queue a CRB, so window should not be busy for too long.
+ * Trying 5ms intervals.
+ */
 static void poll_window_busy_state(struct vas_window *window)
 {
int busy;
u64 val;
 
 retry:
-   /*
-* Poll Window Busy flag
-*/
val = read_hvwc_reg(window, VREG(WIN_STATUS));
busy = GET_FIELD(VAS_WIN_BUSY, val);
if (busy) {
val = 0;
set_current_state(TASK_UNINTERRUPTIBLE);
-   schedule_timeout(HZ);
+   schedule_timeout(msecs_to_jiffies(5));
goto retry;
}
 }
-- 
2.7.4

[PATCH v3 14/18] powerpc: Define set_thread_uses_vas()

[Sukadev Bhattiprolu]

A CP_ABORT instruction is required in processes that have mapped a VAS
"paste address" with the intention of using COPY/PASTE instructions.
But since CP_ABORT is expensive, we want to restrict it to only processes
that use/intend to use COPY/PASTE.

Define an interface, set_thread_uses_vas(), that VAS can use to indicate
that the current process opened a send window. During context switch,
issue CP_ABORT only for processes that have the flag set.

Thanks for input from Nick Piggin, Michael Ellerman.

Cc: Nicholas Piggin <npig...@gmail.com>
Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v3]:
- [Nick Piggin] Rename interface to set_thread_uses_vas(), tweak
  comment and move the CP_ABORT from callers into the interface.
---
 arch/powerpc/include/asm/processor.h |  2 ++
 arch/powerpc/include/asm/switch_to.h |  2 ++
 arch/powerpc/kernel/process.c| 41 +++-
 3 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/include/asm/processor.h 
b/arch/powerpc/include/asm/processor.h
index 58cc212..bdab3b74 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -341,7 +341,9 @@ struct thread_struct {
unsigned long   sier;
unsigned long   mmcr2;
unsignedmmcr0;
+
unsignedused_ebb;
+   unsigned intused_vas;
 #endif
 };
 
diff --git a/arch/powerpc/include/asm/switch_to.h 
b/arch/powerpc/include/asm/switch_to.h
index ad2d762..c3ca42c 100644
--- a/arch/powerpc/include/asm/switch_to.h
+++ b/arch/powerpc/include/asm/switch_to.h
@@ -92,6 +92,8 @@ static inline void clear_task_ebb(struct task_struct *t)
 #endif
 }
 
+extern int set_thread_uses_vas(void);
+
 extern int set_thread_tidr(struct task_struct *t);
 extern void clear_thread_tidr(struct task_struct *t);
 
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index d861fcd..395ca80 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1234,17 +1234,17 @@ struct task_struct *__switch_to(struct task_struct 
*prev,
 * The copy-paste buffer can only store into foreign real
 * addresses, so unprivileged processes can not see the
 * data or use it in any way unless they have foreign real
-* mappings. We don't have a VAS driver that allocates those
-* yet, so no cpabort is required.
+* mappings. If the new process has the foreign real address
+* mappings, we must issue a cp_abort to clear any state and
+* prevent snooping, corruption or a covert channel.
+*
+* DD1 allows paste into normal system memory so we do an
+* unpaired copy, rather than cp_abort, to clear the buffer,
+* since cp_abort is quite expensive.
 */
-   if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
-   /*
-* DD1 allows paste into normal system memory, so we
-* do an unpaired copy here to clear the buffer and
-* prevent a covert channel being set up.
-*
-* cpabort is not used because it is quite expensive.
-*/
+   if (new_thread->used_vas) {
+   asm volatile(PPC_CP_ABORT);
+   } else if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
asm volatile(PPC_COPY(%0, %1)
: : "r"(dummy_copy_buffer), "r"(0));
}
@@ -1445,6 +1445,27 @@ void flush_thread(void)
 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
 }
 
+int set_thread_uses_vas(void)
+{
+#ifdef CONFIG_PPC_BOOK3S_64
+   if (!cpu_has_feature(CPU_FTR_ARCH_300))
+   return -EINVAL;
+
+   current->thread.used_vas = 1;
+
+   /*
+* Even a process that has no foreign real address mapping can use
+* an unpaired COPY instruction (to no real effect). Issue CP_ABORT
+* to clear any pending COPY and prevent a covert channel.
+*
+* __switch_to() will issue CP_ABORT on future context switches.
+*/
+   asm volatile(PPC_CP_ABORT);
+
+#endif /* CONFIG_PPC_BOOK3S_64 */
+   return 0;
+}
+
 #ifdef CONFIG_PPC64
 static DEFINE_SPINLOCK(vas_thread_id_lock);
 static DEFINE_IDA(vas_thread_ida);
-- 
2.7.4

[PATCH v3 17/18] powerpc/vas: Define vas_win_id()

[Sukadev Bhattiprolu]

Define an interface to return a system-wide unique id for a given VAS
window.

The vas_win_id() will be used in a follow-on patch to generate an unique
handle for a user space receive window. Applications can use this handle
to pair send and receive windows for fast thread-wakeup.

The hardware refers to this system-wide unique id as a Partition Send
Window ID which is expected to be used during fault handling. Hence the
"pswid" in the function names.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/vas.h  |  5 +
 arch/powerpc/platforms/powernv/vas-window.c |  9 +
 arch/powerpc/platforms/powernv/vas.h| 28 
 3 files changed, 42 insertions(+)

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index f98ade8..7714562 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -168,6 +168,11 @@ int vas_copy_crb(void *crb, int offset);
 int vas_paste_crb(struct vas_window *win, int offset, bool re);
 
 /*
+ * Return a system-wide unique id for the VAS window @win.
+ */
+extern u32 vas_win_id(struct vas_window *win);
+
+/*
  * Return the power bus paste address associated with @win so the caller
  * can map that address into their address space.
  */
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index d7d0653..8275492 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1235,3 +1235,12 @@ int vas_win_close(struct vas_window *window)
return 0;
 }
 EXPORT_SYMBOL_GPL(vas_win_close);
+
+/*
+ * Return a system-wide unique window id for the window @win.
+ */
+u32 vas_win_id(struct vas_window *win)
+{
+   return encode_pswid(win->vinst->vas_id, win->winid);
+}
+EXPORT_SYMBOL_GPL(vas_win_id);
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index 756cbc5..ae0100f 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -447,4 +447,32 @@ static inline u64 read_hvwc_reg(struct vas_window *win,
return in_be64(win->hvwc_map+reg);
 }
 
+/*
+ * Encode/decode the Partition Send Window ID (PSWID) for a window in
+ * a way that we can uniquely identify any window in the system. i.e.
+ * we should be able to locate the 'struct vas_window' given the PSWID.
+ *
+ * BitsUsage
+ * 0:7 VAS id (8 bits)
+ * 8:15Unused, 0 (3 bits)
+ * 16:31   Window id (16 bits)
+ */
+static inline u32 encode_pswid(int vasid, int winid)
+{
+   u32 pswid = 0;
+
+   pswid |= vasid << (31 - 7);
+   pswid |= winid;
+
+   return pswid;
+}
+
+static inline void decode_pswid(u32 pswid, int *vasid, int *winid)
+{
+   if (vasid)
+   *vasid = pswid >> (31 - 7) & 0xFF;
+
+   if (winid)
+   *winid = pswid & 0x;
+}
 #endif /* _VAS_H */
-- 
2.7.4

[PATCH v3 14/18] powerpc: Define set_thread_uses_vas()

[Sukadev Bhattiprolu]

A CP_ABORT instruction is required in processes that have mapped a VAS
"paste address" with the intention of using COPY/PASTE instructions.
But since CP_ABORT is expensive, we want to restrict it to only processes
that use/intend to use COPY/PASTE.

Define an interface, set_thread_uses_vas(), that VAS can use to indicate
that the current process opened a send window. During context switch,
issue CP_ABORT only for processes that have the flag set.

Thanks for input from Nick Piggin, Michael Ellerman.

Cc: Nicholas Piggin 
Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v3]:
- [Nick Piggin] Rename interface to set_thread_uses_vas(), tweak
  comment and move the CP_ABORT from callers into the interface.
---
 arch/powerpc/include/asm/processor.h |  2 ++
 arch/powerpc/include/asm/switch_to.h |  2 ++
 arch/powerpc/kernel/process.c| 41 +++-
 3 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/include/asm/processor.h 
b/arch/powerpc/include/asm/processor.h
index 58cc212..bdab3b74 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -341,7 +341,9 @@ struct thread_struct {
unsigned long   sier;
unsigned long   mmcr2;
unsignedmmcr0;
+
unsignedused_ebb;
+   unsigned intused_vas;
 #endif
 };
 
diff --git a/arch/powerpc/include/asm/switch_to.h 
b/arch/powerpc/include/asm/switch_to.h
index ad2d762..c3ca42c 100644
--- a/arch/powerpc/include/asm/switch_to.h
+++ b/arch/powerpc/include/asm/switch_to.h
@@ -92,6 +92,8 @@ static inline void clear_task_ebb(struct task_struct *t)
 #endif
 }
 
+extern int set_thread_uses_vas(void);
+
 extern int set_thread_tidr(struct task_struct *t);
 extern void clear_thread_tidr(struct task_struct *t);
 
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index d861fcd..395ca80 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1234,17 +1234,17 @@ struct task_struct *__switch_to(struct task_struct 
*prev,
 * The copy-paste buffer can only store into foreign real
 * addresses, so unprivileged processes can not see the
 * data or use it in any way unless they have foreign real
-* mappings. We don't have a VAS driver that allocates those
-* yet, so no cpabort is required.
+* mappings. If the new process has the foreign real address
+* mappings, we must issue a cp_abort to clear any state and
+* prevent snooping, corruption or a covert channel.
+*
+* DD1 allows paste into normal system memory so we do an
+* unpaired copy, rather than cp_abort, to clear the buffer,
+* since cp_abort is quite expensive.
 */
-   if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
-   /*
-* DD1 allows paste into normal system memory, so we
-* do an unpaired copy here to clear the buffer and
-* prevent a covert channel being set up.
-*
-* cpabort is not used because it is quite expensive.
-*/
+   if (new_thread->used_vas) {
+   asm volatile(PPC_CP_ABORT);
+   } else if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
asm volatile(PPC_COPY(%0, %1)
: : "r"(dummy_copy_buffer), "r"(0));
}
@@ -1445,6 +1445,27 @@ void flush_thread(void)
 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
 }
 
+int set_thread_uses_vas(void)
+{
+#ifdef CONFIG_PPC_BOOK3S_64
+   if (!cpu_has_feature(CPU_FTR_ARCH_300))
+   return -EINVAL;
+
+   current->thread.used_vas = 1;
+
+   /*
+* Even a process that has no foreign real address mapping can use
+* an unpaired COPY instruction (to no real effect). Issue CP_ABORT
+* to clear any pending COPY and prevent a covert channel.
+*
+* __switch_to() will issue CP_ABORT on future context switches.
+*/
+   asm volatile(PPC_CP_ABORT);
+
+#endif /* CONFIG_PPC_BOOK3S_64 */
+   return 0;
+}
+
 #ifdef CONFIG_PPC64
 static DEFINE_SPINLOCK(vas_thread_id_lock);
 static DEFINE_IDA(vas_thread_ida);
-- 
2.7.4

[PATCH v3 17/18] powerpc/vas: Define vas_win_id()

[Sukadev Bhattiprolu]

Define an interface to return a system-wide unique id for a given VAS
window.

The vas_win_id() will be used in a follow-on patch to generate an unique
handle for a user space receive window. Applications can use this handle
to pair send and receive windows for fast thread-wakeup.

The hardware refers to this system-wide unique id as a Partition Send
Window ID which is expected to be used during fault handling. Hence the
"pswid" in the function names.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/include/asm/vas.h  |  5 +
 arch/powerpc/platforms/powernv/vas-window.c |  9 +
 arch/powerpc/platforms/powernv/vas.h| 28 
 3 files changed, 42 insertions(+)

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index f98ade8..7714562 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -168,6 +168,11 @@ int vas_copy_crb(void *crb, int offset);
 int vas_paste_crb(struct vas_window *win, int offset, bool re);
 
 /*
+ * Return a system-wide unique id for the VAS window @win.
+ */
+extern u32 vas_win_id(struct vas_window *win);
+
+/*
  * Return the power bus paste address associated with @win so the caller
  * can map that address into their address space.
  */
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index d7d0653..8275492 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -1235,3 +1235,12 @@ int vas_win_close(struct vas_window *window)
return 0;
 }
 EXPORT_SYMBOL_GPL(vas_win_close);
+
+/*
+ * Return a system-wide unique window id for the window @win.
+ */
+u32 vas_win_id(struct vas_window *win)
+{
+   return encode_pswid(win->vinst->vas_id, win->winid);
+}
+EXPORT_SYMBOL_GPL(vas_win_id);
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index 756cbc5..ae0100f 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -447,4 +447,32 @@ static inline u64 read_hvwc_reg(struct vas_window *win,
return in_be64(win->hvwc_map+reg);
 }
 
+/*
+ * Encode/decode the Partition Send Window ID (PSWID) for a window in
+ * a way that we can uniquely identify any window in the system. i.e.
+ * we should be able to locate the 'struct vas_window' given the PSWID.
+ *
+ * BitsUsage
+ * 0:7 VAS id (8 bits)
+ * 8:15Unused, 0 (3 bits)
+ * 16:31   Window id (16 bits)
+ */
+static inline u32 encode_pswid(int vasid, int winid)
+{
+   u32 pswid = 0;
+
+   pswid |= vasid << (31 - 7);
+   pswid |= winid;
+
+   return pswid;
+}
+
+static inline void decode_pswid(u32 pswid, int *vasid, int *winid)
+{
+   if (vasid)
+   *vasid = pswid >> (31 - 7) & 0xFF;
+
+   if (winid)
+   *winid = pswid & 0x;
+}
 #endif /* _VAS_H */
-- 
2.7.4

[PATCH v3 10/18] powerpc/vas, nx-842: Define and use chip_to_vas_id()

[Sukadev Bhattiprolu]

Define a helper, chip_to_vas_id() to map a given chip id to corresponding
vas id.

Normally, callers of vas_rx_win_open() and vas_tx_win_open() want the VAS
window to be on the same chip where the calling thread is executing. These
callers can pass in -1 for the VAS id.

This interface will be useful if a thread running on one chip wants to open
a window on another chip (like the NX-842 driver does during start up).

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/vas.h   |  9 +
 arch/powerpc/platforms/powernv/vas.c | 11 +++
 drivers/crypto/nx/nx-842-powernv.c   | 18 +++---
 3 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index fd5963a..044748f 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -104,6 +104,15 @@ struct vas_tx_win_attr {
 };
 
 /*
+ * Helper to map a chip id to VAS id.
+ * For POWER9, this is a 1:1 mapping. In the future this maybe a 1:N
+ * mapping in which case, we will need to update this helper.
+ *
+ * Return the VAS id or -1 if no matching vasid is found.
+ */
+int chip_to_vas_id(int chipid);
+
+/*
  * Helper to initialize receive window attributes to defaults for an
  * NX window.
  */
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index abb7090..cd9a733 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -123,6 +123,17 @@ struct vas_instance *find_vas_instance(int vasid)
return NULL;
 }
 
+int chip_to_vas_id(int chipid)
+{
+   int cpu;
+
+   for_each_possible_cpu(cpu) {
+   if (cpu_to_chip_id(cpu) == chipid)
+   return per_cpu(cpu_vas_id, cpu);
+   }
+   return -1;
+}
+
 static int vas_probe(struct platform_device *pdev)
 {
return init_vas_instance(pdev);
diff --git a/drivers/crypto/nx/nx-842-powernv.c 
b/drivers/crypto/nx/nx-842-powernv.c
index 874ddf5..eb221ed 100644
--- a/drivers/crypto/nx/nx-842-powernv.c
+++ b/drivers/crypto/nx/nx-842-powernv.c
@@ -847,24 +847,12 @@ static int __init nx842_powernv_probe_vas(struct 
device_node *pn)
return -EINVAL;
}
 
-   for_each_compatible_node(dn, NULL, "ibm,power9-vas-x") {
-   if (of_get_ibm_chip_id(dn) == chip_id)
-   break;
-   }
-
-   if (!dn) {
-   pr_err("Missing VAS device node\n");
+   vasid = chip_to_vas_id(chip_id);
+   if (vasid < 0) {
+   pr_err("Unable to map chip_id %d to vasid\n", chip_id);
return -EINVAL;
}
 
-   if (of_property_read_u32(dn, "ibm,vas-id", )) {
-   pr_err("Missing ibm,vas-id device property\n");
-   of_node_put(dn);
-   return -EINVAL;
-   }
-
-   of_node_put(dn);
-
for_each_child_of_node(pn, dn) {
if (of_device_is_compatible(dn, "ibm,p9-nx-842")) {
ret = vas_cfg_coproc_info(dn, chip_id, vasid);
-- 
2.7.4

[PATCH v3 10/18] powerpc/vas, nx-842: Define and use chip_to_vas_id()

[Sukadev Bhattiprolu]

Define a helper, chip_to_vas_id() to map a given chip id to corresponding
vas id.

Normally, callers of vas_rx_win_open() and vas_tx_win_open() want the VAS
window to be on the same chip where the calling thread is executing. These
callers can pass in -1 for the VAS id.

This interface will be useful if a thread running on one chip wants to open
a window on another chip (like the NX-842 driver does during start up).

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/include/asm/vas.h   |  9 +
 arch/powerpc/platforms/powernv/vas.c | 11 +++
 drivers/crypto/nx/nx-842-powernv.c   | 18 +++---
 3 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index fd5963a..044748f 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -104,6 +104,15 @@ struct vas_tx_win_attr {
 };
 
 /*
+ * Helper to map a chip id to VAS id.
+ * For POWER9, this is a 1:1 mapping. In the future this maybe a 1:N
+ * mapping in which case, we will need to update this helper.
+ *
+ * Return the VAS id or -1 if no matching vasid is found.
+ */
+int chip_to_vas_id(int chipid);
+
+/*
  * Helper to initialize receive window attributes to defaults for an
  * NX window.
  */
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index abb7090..cd9a733 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -123,6 +123,17 @@ struct vas_instance *find_vas_instance(int vasid)
return NULL;
 }
 
+int chip_to_vas_id(int chipid)
+{
+   int cpu;
+
+   for_each_possible_cpu(cpu) {
+   if (cpu_to_chip_id(cpu) == chipid)
+   return per_cpu(cpu_vas_id, cpu);
+   }
+   return -1;
+}
+
 static int vas_probe(struct platform_device *pdev)
 {
return init_vas_instance(pdev);
diff --git a/drivers/crypto/nx/nx-842-powernv.c 
b/drivers/crypto/nx/nx-842-powernv.c
index 874ddf5..eb221ed 100644
--- a/drivers/crypto/nx/nx-842-powernv.c
+++ b/drivers/crypto/nx/nx-842-powernv.c
@@ -847,24 +847,12 @@ static int __init nx842_powernv_probe_vas(struct 
device_node *pn)
return -EINVAL;
}
 
-   for_each_compatible_node(dn, NULL, "ibm,power9-vas-x") {
-   if (of_get_ibm_chip_id(dn) == chip_id)
-   break;
-   }
-
-   if (!dn) {
-   pr_err("Missing VAS device node\n");
+   vasid = chip_to_vas_id(chip_id);
+   if (vasid < 0) {
+   pr_err("Unable to map chip_id %d to vasid\n", chip_id);
return -EINVAL;
}
 
-   if (of_property_read_u32(dn, "ibm,vas-id", )) {
-   pr_err("Missing ibm,vas-id device property\n");
-   of_node_put(dn);
-   return -EINVAL;
-   }
-
-   of_node_put(dn);
-
for_each_child_of_node(pn, dn) {
if (of_device_is_compatible(dn, "ibm,p9-nx-842")) {
ret = vas_cfg_coproc_info(dn, chip_id, vasid);
-- 
2.7.4

[PATCH v3 15/18] powerpc: Emulate paste instruction

[Sukadev Bhattiprolu]

From: Michael Neuling <mi...@neuling.org>

On POWER9 DD2.1 and below there are issues when the paste instruction
generates an error. If an error occurs when thread reconfiguration
happens (ie another thread in the core goes into/out of powersave) the
core may hang.

To avoid this a special sequence is required which stops thread
configuration so that the paste can be safely executed.

This patch assumes paste executed in userspace are trapped into the
illegal instruction exception at 0xe40.

Here we re-execute the paste instruction but with the required
sequence to ensure thread reconfiguration doesn't occur.

Cc: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
Signed-off-by: Michael Neuling <mi...@neuling.org>
Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changlog[v3]:
- [Michael Ellerman] We don't need to disable/enable pagefaults
  when emulating paste;
- [Michael Ellerman, Aneesh Kumar] Fix retval from emulate_paste()

Edit by Sukadev: Use PPC_PASTE() rather than the paste instruction since
in older versions the instruction required a third parameter.
---
 arch/powerpc/include/asm/emulated_ops.h |  1 +
 arch/powerpc/include/asm/ppc-opcode.h   |  1 +
 arch/powerpc/include/asm/reg.h  |  2 +
 arch/powerpc/kernel/traps.c | 67 +
 4 files changed, 71 insertions(+)

diff --git a/arch/powerpc/include/asm/emulated_ops.h 
b/arch/powerpc/include/asm/emulated_ops.h
index f00e10e..9247af9 100644
--- a/arch/powerpc/include/asm/emulated_ops.h
+++ b/arch/powerpc/include/asm/emulated_ops.h
@@ -55,6 +55,7 @@ extern struct ppc_emulated {
struct ppc_emulated_entry mfdscr;
struct ppc_emulated_entry mtdscr;
struct ppc_emulated_entry lq_stq;
+   struct ppc_emulated_entry paste;
 #endif
 } ppc_emulated;
 
diff --git a/arch/powerpc/include/asm/ppc-opcode.h 
b/arch/powerpc/include/asm/ppc-opcode.h
index ce0930d..a55d2ef 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -229,6 +229,7 @@
 #define PPC_INST_MTTMR 0x7c0003dc
 #define PPC_INST_NOP   0x6000
 #define PPC_INST_PASTE 0x7c20070d
+#define PPC_INST_PASTE_MASK0xfc2007ff
 #define PPC_INST_POPCNTB   0x7cf4
 #define PPC_INST_POPCNTB_MASK  0xfc0007fe
 #define PPC_INST_POPCNTD   0x7c0003f4
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index b779f3c..3495ecf 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -469,6 +469,8 @@
 #define SPRN_DBAT7U0x23E   /* Data BAT 7 Upper Register */
 #define SPRN_PPR   0x380   /* SMT Thread status Register */
 #define SPRN_TSCR  0x399   /* Thread Switch Control Register */
+#define SPRN_TRIG1 0x371   /* WAT Trigger 1 */
+#define SPRN_TRIG2 0x372   /* WAT Trigger 2 */
 
 #define SPRN_DEC   0x016   /* Decrement Register */
 #define SPRN_DER   0x095   /* Debug Enable Register */
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 13c9dcd..c2cce25 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -956,6 +956,68 @@ static inline bool tm_abort_check(struct pt_regs *regs, 
int reason)
 }
 #endif
 
+static DEFINE_SPINLOCK(paste_emulation_lock);
+
+static inline int paste(void *i)
+{
+   int cr;
+   long retval = 0;
+
+   /* Need per core lock to ensure trig1/2 writes don't race */
+   spin_lock(_emulation_lock);
+   mtspr(SPRN_TRIG1, 0); /* data doesn't matter */
+   mtspr(SPRN_TRIG1, 0); /* HW says do this twice */
+   asm volatile(
+   "1: " PPC_PASTE(0, %2) "\n"
+   "2: mfcr %1\n"
+   ".section .fixup,\"ax\"\n"
+   "3: li %0,%3\n"
+   "   li %2,0\n"
+   "   b 2b\n"
+   ".previous\n"
+   EX_TABLE(1b, 3b)
+   : "=r" (retval), "=r" (cr)
+   : "b" (i), "i" (-EFAULT), "0" (retval));
+   mtspr(SPRN_TRIG2, 0);
+   spin_unlock(_emulation_lock);
+
+   return retval ?: cr;
+}
+
+static int emulate_paste(struct pt_regs *regs, u32 instword)
+{
+   const void __user *addr;
+   unsigned long ea;
+   u8 ra, rb;
+   int rc;
+
+   if (!cpu_has_feature(CPU_FTR_ARCH_300))
+   return -EINVAL;
+
+   ra = (instword >> 16) & 0x1f;
+   rb = (instword >> 11) & 0x1f;
+
+   ea = regs->gpr[rb] + (ra ? regs->gpr[ra] : 0ul);
+   if (is_32bit_task())
+   ea &= 0xul;
+   addr = (__force const void __user *)ea;
+
+   if (!access_ok(VERIFY_WRITE, addr, 128)) // cacheline size == 128
+   return -

[PATCH v3 15/18] powerpc: Emulate paste instruction

[Sukadev Bhattiprolu]

From: Michael Neuling 

On POWER9 DD2.1 and below there are issues when the paste instruction
generates an error. If an error occurs when thread reconfiguration
happens (ie another thread in the core goes into/out of powersave) the
core may hang.

To avoid this a special sequence is required which stops thread
configuration so that the paste can be safely executed.

This patch assumes paste executed in userspace are trapped into the
illegal instruction exception at 0xe40.

Here we re-execute the paste instruction but with the required
sequence to ensure thread reconfiguration doesn't occur.

Cc: Aneesh Kumar K.V 
Signed-off-by: Michael Neuling 
Signed-off-by: Sukadev Bhattiprolu 
---
Changlog[v3]:
- [Michael Ellerman] We don't need to disable/enable pagefaults
  when emulating paste;
- [Michael Ellerman, Aneesh Kumar] Fix retval from emulate_paste()

Edit by Sukadev: Use PPC_PASTE() rather than the paste instruction since
in older versions the instruction required a third parameter.
---
 arch/powerpc/include/asm/emulated_ops.h |  1 +
 arch/powerpc/include/asm/ppc-opcode.h   |  1 +
 arch/powerpc/include/asm/reg.h  |  2 +
 arch/powerpc/kernel/traps.c | 67 +
 4 files changed, 71 insertions(+)

diff --git a/arch/powerpc/include/asm/emulated_ops.h 
b/arch/powerpc/include/asm/emulated_ops.h
index f00e10e..9247af9 100644
--- a/arch/powerpc/include/asm/emulated_ops.h
+++ b/arch/powerpc/include/asm/emulated_ops.h
@@ -55,6 +55,7 @@ extern struct ppc_emulated {
struct ppc_emulated_entry mfdscr;
struct ppc_emulated_entry mtdscr;
struct ppc_emulated_entry lq_stq;
+   struct ppc_emulated_entry paste;
 #endif
 } ppc_emulated;
 
diff --git a/arch/powerpc/include/asm/ppc-opcode.h 
b/arch/powerpc/include/asm/ppc-opcode.h
index ce0930d..a55d2ef 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -229,6 +229,7 @@
 #define PPC_INST_MTTMR 0x7c0003dc
 #define PPC_INST_NOP   0x6000
 #define PPC_INST_PASTE 0x7c20070d
+#define PPC_INST_PASTE_MASK0xfc2007ff
 #define PPC_INST_POPCNTB   0x7cf4
 #define PPC_INST_POPCNTB_MASK  0xfc0007fe
 #define PPC_INST_POPCNTD   0x7c0003f4
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index b779f3c..3495ecf 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -469,6 +469,8 @@
 #define SPRN_DBAT7U0x23E   /* Data BAT 7 Upper Register */
 #define SPRN_PPR   0x380   /* SMT Thread status Register */
 #define SPRN_TSCR  0x399   /* Thread Switch Control Register */
+#define SPRN_TRIG1 0x371   /* WAT Trigger 1 */
+#define SPRN_TRIG2 0x372   /* WAT Trigger 2 */
 
 #define SPRN_DEC   0x016   /* Decrement Register */
 #define SPRN_DER   0x095   /* Debug Enable Register */
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 13c9dcd..c2cce25 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -956,6 +956,68 @@ static inline bool tm_abort_check(struct pt_regs *regs, 
int reason)
 }
 #endif
 
+static DEFINE_SPINLOCK(paste_emulation_lock);
+
+static inline int paste(void *i)
+{
+   int cr;
+   long retval = 0;
+
+   /* Need per core lock to ensure trig1/2 writes don't race */
+   spin_lock(_emulation_lock);
+   mtspr(SPRN_TRIG1, 0); /* data doesn't matter */
+   mtspr(SPRN_TRIG1, 0); /* HW says do this twice */
+   asm volatile(
+   "1: " PPC_PASTE(0, %2) "\n"
+   "2: mfcr %1\n"
+   ".section .fixup,\"ax\"\n"
+   "3: li %0,%3\n"
+   "   li %2,0\n"
+   "   b 2b\n"
+   ".previous\n"
+   EX_TABLE(1b, 3b)
+   : "=r" (retval), "=r" (cr)
+   : "b" (i), "i" (-EFAULT), "0" (retval));
+   mtspr(SPRN_TRIG2, 0);
+   spin_unlock(_emulation_lock);
+
+   return retval ?: cr;
+}
+
+static int emulate_paste(struct pt_regs *regs, u32 instword)
+{
+   const void __user *addr;
+   unsigned long ea;
+   u8 ra, rb;
+   int rc;
+
+   if (!cpu_has_feature(CPU_FTR_ARCH_300))
+   return -EINVAL;
+
+   ra = (instword >> 16) & 0x1f;
+   rb = (instword >> 11) & 0x1f;
+
+   ea = regs->gpr[rb] + (ra ? regs->gpr[ra] : 0ul);
+   if (is_32bit_task())
+   ea &= 0xul;
+   addr = (__force const void __user *)ea;
+
+   if (!access_ok(VERIFY_WRITE, addr, 128)) // cacheline size == 128
+   return -EFAULT;
+
+   hard_irq_disable(); /* FIXME: could we just soft disable ?? */
+
+   PPC_WARN_EMULATED(paste, reg

[PATCH v3 13/18] powerpc: Add support for setting SPRN_TIDR

[Sukadev Bhattiprolu]

We need the SPRN_TIDR to be set for use with fast thread-wakeup (core-
to-core wakeup) and also with CAPI.

Each thread in a process needs to have a unique id within the process.
But as explained below, for now, we assign globally unique thread ids
to all threads in the system.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Signed-off-by: Philippe Bergheaud <fe...@linux.vnet.ibm.com>
Signed-off-by: Christophe Lombard <clomb...@linux.vnet.ibm.com>
---
Changelog[v3]
- Merge changes with and address comments to Christophe's patch.
  (i.e drop CONFIG_PPC_VAS; use CONFIG_PPC64; check CPU_ARCH_300
  before setting TIDR). Defer following to separate patches:
- emulation parts of Christophe's patch,
- setting TIDR for tasks other than 'current'
- setting feature bit in AT_HWCAP2

Changelog[v2]
- Michael Ellerman: Use an interface to assign TIDR so it is
assigned to only threads that need it; move assignment to
restore_sprs(). Drop lint from rebase;
---
 arch/powerpc/include/asm/processor.h |   1 +
 arch/powerpc/include/asm/switch_to.h |   3 +
 arch/powerpc/kernel/process.c| 122 +++
 3 files changed, 126 insertions(+)

diff --git a/arch/powerpc/include/asm/processor.h 
b/arch/powerpc/include/asm/processor.h
index fab7ff8..58cc212 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -329,6 +329,7 @@ struct thread_struct {
 */
int dscr_inherit;
unsigned long   ppr;/* used to save/restore SMT priority */
+   unsigned long   tidr;
 #endif
 #ifdef CONFIG_PPC_BOOK3S_64
unsigned long   tar;
diff --git a/arch/powerpc/include/asm/switch_to.h 
b/arch/powerpc/include/asm/switch_to.h
index bf820f5..ad2d762 100644
--- a/arch/powerpc/include/asm/switch_to.h
+++ b/arch/powerpc/include/asm/switch_to.h
@@ -92,4 +92,7 @@ static inline void clear_task_ebb(struct task_struct *t)
 #endif
 }
 
+extern int set_thread_tidr(struct task_struct *t);
+extern void clear_thread_tidr(struct task_struct *t);
+
 #endif /* _ASM_POWERPC_SWITCH_TO_H */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 37ed60b..d861fcd 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1120,6 +1120,13 @@ static inline void restore_sprs(struct thread_struct 
*old_thread,
mtspr(SPRN_TAR, new_thread->tar);
}
 #endif
+#ifdef CONFIG_PPC64
+   if (old_thread->tidr != new_thread->tidr) {
+   /* TIDR should be non-zero only with ISA3.0. */
+   WARN_ON_ONCE(!cpu_has_feature(CPU_FTR_ARCH_300));
+   mtspr(SPRN_TIDR, new_thread->tidr);
+   }
+#endif
 }
 
 #ifdef CONFIG_PPC_BOOK3S_64
@@ -1438,9 +1445,117 @@ void flush_thread(void)
 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
 }
 
+#ifdef CONFIG_PPC64
+static DEFINE_SPINLOCK(vas_thread_id_lock);
+static DEFINE_IDA(vas_thread_ida);
+
+/*
+ * We need to assign a unique thread id to each thread in a process.
+ *
+ * This thread id, referred to as TIDR, and separate from the Linux's tgid,
+ * is intended to be used to direct an ASB_Notify from the hardware to the
+ * thread, when a suitable event occurs in the system.
+ *
+ * One such event is a "paste" instruction in the context of Fast Thread
+ * Wakeup (aka Core-to-core wake up in the Virtual Accelerator Switchboard
+ * (VAS) in POWER9.
+ *
+ * To get a unique TIDR per process we could simply reuse task_pid_nr() but
+ * the problem is that task_pid_nr() is not yet available copy_thread() is
+ * called. Fixing that would require changing more intrusive arch-neutral
+ * code in code path in copy_process()?.
+ *
+ * Further, to assign unique TIDRs within each process, we need an atomic
+ * field (or an IDR) in task_struct, which again intrudes into the arch-
+ * neutral code. So try to assign globally unique TIDRs for now.
+ *
+ * NOTE: TIDR 0 indicates that the thread does not need a TIDR value.
+ *  For now, only threads that expect to be notified by the VAS
+ *  hardware need a TIDR value and we assign values > 0 for those.
+ */
+#define MAX_THREAD_CONTEXT ((1 << 16) - 1)
+static int assign_thread_tidr(void)
+{
+   int index;
+   int err;
+
+again:
+   if (!ida_pre_get(_thread_ida, GFP_KERNEL))
+   return -ENOMEM;
+
+   spin_lock(_thread_id_lock);
+   err = ida_get_new_above(_thread_ida, 1, );
+   spin_unlock(_thread_id_lock);
+
+   if (err == -EAGAIN)
+   goto again;
+   else if (err)
+   return err;
+
+   if (index > MAX_THREAD_CONTEXT) {
+   spin_lock(_thread_id_lock);
+   ida_remove(_thread_ida, index);
+   spin_unlock(_thread_id_lock);
+   return -ENOMEM;
+   }
+
+   return index;
+}
+
+stati

[PATCH v3 13/18] powerpc: Add support for setting SPRN_TIDR

[Sukadev Bhattiprolu]

We need the SPRN_TIDR to be set for use with fast thread-wakeup (core-
to-core wakeup) and also with CAPI.

Each thread in a process needs to have a unique id within the process.
But as explained below, for now, we assign globally unique thread ids
to all threads in the system.

Signed-off-by: Sukadev Bhattiprolu 
Signed-off-by: Philippe Bergheaud 
Signed-off-by: Christophe Lombard 
---
Changelog[v3]
- Merge changes with and address comments to Christophe's patch.
  (i.e drop CONFIG_PPC_VAS; use CONFIG_PPC64; check CPU_ARCH_300
  before setting TIDR). Defer following to separate patches:
- emulation parts of Christophe's patch,
- setting TIDR for tasks other than 'current'
- setting feature bit in AT_HWCAP2

Changelog[v2]
- Michael Ellerman: Use an interface to assign TIDR so it is
assigned to only threads that need it; move assignment to
restore_sprs(). Drop lint from rebase;
---
 arch/powerpc/include/asm/processor.h |   1 +
 arch/powerpc/include/asm/switch_to.h |   3 +
 arch/powerpc/kernel/process.c| 122 +++
 3 files changed, 126 insertions(+)

diff --git a/arch/powerpc/include/asm/processor.h 
b/arch/powerpc/include/asm/processor.h
index fab7ff8..58cc212 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -329,6 +329,7 @@ struct thread_struct {
 */
int dscr_inherit;
unsigned long   ppr;/* used to save/restore SMT priority */
+   unsigned long   tidr;
 #endif
 #ifdef CONFIG_PPC_BOOK3S_64
unsigned long   tar;
diff --git a/arch/powerpc/include/asm/switch_to.h 
b/arch/powerpc/include/asm/switch_to.h
index bf820f5..ad2d762 100644
--- a/arch/powerpc/include/asm/switch_to.h
+++ b/arch/powerpc/include/asm/switch_to.h
@@ -92,4 +92,7 @@ static inline void clear_task_ebb(struct task_struct *t)
 #endif
 }
 
+extern int set_thread_tidr(struct task_struct *t);
+extern void clear_thread_tidr(struct task_struct *t);
+
 #endif /* _ASM_POWERPC_SWITCH_TO_H */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 37ed60b..d861fcd 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1120,6 +1120,13 @@ static inline void restore_sprs(struct thread_struct 
*old_thread,
mtspr(SPRN_TAR, new_thread->tar);
}
 #endif
+#ifdef CONFIG_PPC64
+   if (old_thread->tidr != new_thread->tidr) {
+   /* TIDR should be non-zero only with ISA3.0. */
+   WARN_ON_ONCE(!cpu_has_feature(CPU_FTR_ARCH_300));
+   mtspr(SPRN_TIDR, new_thread->tidr);
+   }
+#endif
 }
 
 #ifdef CONFIG_PPC_BOOK3S_64
@@ -1438,9 +1445,117 @@ void flush_thread(void)
 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
 }
 
+#ifdef CONFIG_PPC64
+static DEFINE_SPINLOCK(vas_thread_id_lock);
+static DEFINE_IDA(vas_thread_ida);
+
+/*
+ * We need to assign a unique thread id to each thread in a process.
+ *
+ * This thread id, referred to as TIDR, and separate from the Linux's tgid,
+ * is intended to be used to direct an ASB_Notify from the hardware to the
+ * thread, when a suitable event occurs in the system.
+ *
+ * One such event is a "paste" instruction in the context of Fast Thread
+ * Wakeup (aka Core-to-core wake up in the Virtual Accelerator Switchboard
+ * (VAS) in POWER9.
+ *
+ * To get a unique TIDR per process we could simply reuse task_pid_nr() but
+ * the problem is that task_pid_nr() is not yet available copy_thread() is
+ * called. Fixing that would require changing more intrusive arch-neutral
+ * code in code path in copy_process()?.
+ *
+ * Further, to assign unique TIDRs within each process, we need an atomic
+ * field (or an IDR) in task_struct, which again intrudes into the arch-
+ * neutral code. So try to assign globally unique TIDRs for now.
+ *
+ * NOTE: TIDR 0 indicates that the thread does not need a TIDR value.
+ *  For now, only threads that expect to be notified by the VAS
+ *  hardware need a TIDR value and we assign values > 0 for those.
+ */
+#define MAX_THREAD_CONTEXT ((1 << 16) - 1)
+static int assign_thread_tidr(void)
+{
+   int index;
+   int err;
+
+again:
+   if (!ida_pre_get(_thread_ida, GFP_KERNEL))
+   return -ENOMEM;
+
+   spin_lock(_thread_id_lock);
+   err = ida_get_new_above(_thread_ida, 1, );
+   spin_unlock(_thread_id_lock);
+
+   if (err == -EAGAIN)
+   goto again;
+   else if (err)
+   return err;
+
+   if (index > MAX_THREAD_CONTEXT) {
+   spin_lock(_thread_id_lock);
+   ida_remove(_thread_ida, index);
+   spin_unlock(_thread_id_lock);
+   return -ENOMEM;
+   }
+
+   return index;
+}
+
+static void free_thread_tidr(int id)
+{
+   spin_lock(_thread_id_lock);
+   ida_remove(_thread_ida, id);
+

[PATCH v3 02/18] powerpc/vas: Validate window credits

[Sukadev Bhattiprolu]

NX-842, the only user of VAS, sets the window credits to default values
but VAS should check the credits against the possible max values.

The VAS_WCREDS_MIN is not needed and can be dropped.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 6 ++
 arch/powerpc/platforms/powernv/vas.h| 4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index cec7ab7..a2fe120 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -738,6 +738,9 @@ static bool rx_win_args_valid(enum vas_cop_type cop,
if (attr->rx_fifo_size > VAS_RX_FIFO_SIZE_MAX)
return false;
 
+   if (attr->wcreds_max > VAS_RX_WCREDS_MAX)
+   return false;
+
if (attr->nx_win) {
/* cannot be fault or user window if it is nx */
if (attr->fault_win || attr->user_win)
@@ -927,6 +930,9 @@ static bool tx_win_args_valid(enum vas_cop_type cop,
if (cop > VAS_COP_TYPE_MAX)
return false;
 
+   if (attr->wcreds_max > VAS_TX_WCREDS_MAX)
+   return false;
+
if (attr->user_win &&
(cop != VAS_COP_TYPE_FTW || attr->rsvd_txbuf_count))
return false;
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index 38dee5d..fea0de4 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -106,8 +106,8 @@
  *
  * TODO: Needs tuning for per-process credits
  */
-#define VAS_WCREDS_MIN 16
-#define VAS_WCREDS_MAX ((64 << 10) - 1)
+#define VAS_RX_WCREDS_MAX  ((64 << 10) - 1)
+#define VAS_TX_WCREDS_MAX  ((4 << 10) - 1)
 #define VAS_WCREDS_DEFAULT (1 << 10)
 
 /*
-- 
2.7.4

[PATCH v3 02/18] powerpc/vas: Validate window credits

[Sukadev Bhattiprolu]

NX-842, the only user of VAS, sets the window credits to default values
but VAS should check the credits against the possible max values.

The VAS_WCREDS_MIN is not needed and can be dropped.

Signed-off-by: Sukadev Bhattiprolu 
---
 arch/powerpc/platforms/powernv/vas-window.c | 6 ++
 arch/powerpc/platforms/powernv/vas.h| 4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index cec7ab7..a2fe120 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -738,6 +738,9 @@ static bool rx_win_args_valid(enum vas_cop_type cop,
if (attr->rx_fifo_size > VAS_RX_FIFO_SIZE_MAX)
return false;
 
+   if (attr->wcreds_max > VAS_RX_WCREDS_MAX)
+   return false;
+
if (attr->nx_win) {
/* cannot be fault or user window if it is nx */
if (attr->fault_win || attr->user_win)
@@ -927,6 +930,9 @@ static bool tx_win_args_valid(enum vas_cop_type cop,
if (cop > VAS_COP_TYPE_MAX)
return false;
 
+   if (attr->wcreds_max > VAS_TX_WCREDS_MAX)
+   return false;
+
if (attr->user_win &&
(cop != VAS_COP_TYPE_FTW || attr->rsvd_txbuf_count))
return false;
diff --git a/arch/powerpc/platforms/powernv/vas.h 
b/arch/powerpc/platforms/powernv/vas.h
index 38dee5d..fea0de4 100644
--- a/arch/powerpc/platforms/powernv/vas.h
+++ b/arch/powerpc/platforms/powernv/vas.h
@@ -106,8 +106,8 @@
  *
  * TODO: Needs tuning for per-process credits
  */
-#define VAS_WCREDS_MIN 16
-#define VAS_WCREDS_MAX ((64 << 10) - 1)
+#define VAS_RX_WCREDS_MAX  ((64 << 10) - 1)
+#define VAS_TX_WCREDS_MAX  ((4 << 10) - 1)
 #define VAS_WCREDS_DEFAULT (1 << 10)
 
 /*
-- 
2.7.4

[PATCH v3 16/18] powerpc/vas: Define vas_win_paste_addr()

[Sukadev Bhattiprolu]

Define an interface that the NX drivers can use to find the physical
paste address of a send window. This interface is expected to be used
with the mmap() operation of the NX driver's device. i.e the user space
process can use driver's mmap() operation to map the send window's paste
address into their address space and then use copy and paste instructions
to submit the CRBs to the NX engine.

Note that kernel drivers will use vas_paste_crb() directly and don't need
this interface.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/vas.h  |  7 +++
 arch/powerpc/platforms/powernv/vas-window.c | 10 ++
 2 files changed, 17 insertions(+)

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index 044748f..f98ade8 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -10,6 +10,8 @@
 #ifndef _ASM_POWERPC_VAS_H
 #define _ASM_POWERPC_VAS_H
 
+struct vas_window;
+
 /*
  * Min and max FIFO sizes are based on Version 1.05 Section 3.1.4.25
  * (Local FIFO Size Register) of the VAS workbook.
@@ -165,4 +167,9 @@ int vas_copy_crb(void *crb, int offset);
  */
 int vas_paste_crb(struct vas_window *win, int offset, bool re);
 
+/*
+ * Return the power bus paste address associated with @win so the caller
+ * can map that address into their address space.
+ */
+extern u64 vas_win_paste_addr(struct vas_window *win);
 #endif /* __ASM_POWERPC_VAS_H */
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index c030d4c..d7d0653 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -40,6 +40,16 @@ static void compute_paste_address(struct vas_window *window, 
u64 *addr, int *len
pr_debug("Txwin #%d: Paste addr 0x%llx\n", winid, *addr);
 }
 
+u64 vas_win_paste_addr(struct vas_window *win)
+{
+   u64 addr;
+
+   compute_paste_address(win, , NULL);
+
+   return addr;
+}
+EXPORT_SYMBOL(vas_win_paste_addr);
+
 static inline void get_hvwc_mmio_bar(struct vas_window *window,
u64 *start, int *len)
 {
-- 
2.7.4

[PATCH v3 18/18] powerpc/vas: Add support for user receive window

[Sukadev Bhattiprolu]

Add support for user space receive window (for the Fast thread-wakeup
coprocessor type)

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v3]
- [Nick Piggin] Drop CP_ABORT since set_thread_uses_vas() does
  that now (in earlier patch) and add a check for return value.
---
 arch/powerpc/platforms/powernv/vas-window.c | 56 +
 1 file changed, 49 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 8275492..2b3eb01 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -16,7 +16,8 @@
 #include 
 #include 
 #include 
-
+#include 
+#include 
 #include "vas.h"
 #include "copy-paste.h"
 
@@ -598,6 +599,32 @@ static void put_rx_win(struct vas_window *rxwin)
 }
 
 /*
+ * Find the user space receive window given the @pswid.
+ *  - We must have a valid vasid and it must belong to this instance.
+ *(so both send and receive windows are on the same VAS instance)
+ *  - The window must refer to an OPEN, FTW, RECEIVE window.
+ *
+ * NOTE: We access ->windows[] table and assume that vinst->mutex is held.
+ */
+static struct vas_window *get_user_rxwin(struct vas_instance *vinst, u32 pswid)
+{
+   int vasid, winid;
+   struct vas_window *rxwin;
+
+   decode_pswid(pswid, , );
+
+   if (vinst->vas_id != vasid)
+   return ERR_PTR(-EINVAL);
+
+   rxwin = vinst->windows[winid];
+
+   if (!rxwin || rxwin->tx_win || rxwin->cop != VAS_COP_TYPE_FTW)
+   return ERR_PTR(-EINVAL);
+
+   return rxwin;
+}
+
+/*
  * Get the VAS receive window associated with NX engine identified
  * by @cop and if applicable, @pswid.
  *
@@ -610,10 +637,10 @@ static struct vas_window *get_vinst_rxwin(struct 
vas_instance *vinst,
 
mutex_lock(>mutex);
 
-   if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI)
-   rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL);
+   if (cop == VAS_COP_TYPE_FTW)
+   rxwin = get_user_rxwin(vinst, pswid);
else
-   rxwin = ERR_PTR(-EINVAL);
+   rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL);
 
if (!IS_ERR(rxwin))
atomic_inc(>num_txwins);
@@ -937,10 +964,9 @@ static void init_winctx_for_txwin(struct vas_window *txwin,
winctx->tx_word_mode = txattr->tx_win_ord_mode;
winctx->rsvd_txbuf_count = txattr->rsvd_txbuf_count;
 
-   if (winctx->nx_win) {
+   winctx->intr_disable = true;
+   if (winctx->nx_win)
winctx->data_stamp = true;
-   winctx->intr_disable = true;
-   }
 
winctx->lpid = txattr->lpid;
winctx->pidr = txattr->pidr;
@@ -985,6 +1011,14 @@ struct vas_window *vas_tx_win_open(int vasid, enum 
vas_cop_type cop,
if (!tx_win_args_valid(cop, attr))
return ERR_PTR(-EINVAL);
 
+   /*
+* If caller did not specify a vasid but specified the PSWID of a
+* receive window (applicable only to FTW windows), use the vasid
+* from that receive window.
+*/
+   if (vasid == -1 && attr->pswid)
+   decode_pswid(attr->pswid, , NULL);
+
vinst = find_vas_instance(vasid);
if (!vinst) {
pr_devel("vasid %d not found!\n", vasid);
@@ -1031,6 +1065,14 @@ struct vas_window *vas_tx_win_open(int vasid, enum 
vas_cop_type cop,
}
}
 
+   /*
+* Now that we have a send window, ensure context switch issues
+* CP_ABORT for this thread.
+*/
+   rc = -EINVAL;
+   if (set_thread_uses_vas() < 0)
+   goto free_window;
+
set_vinst_win(vinst, txwin);
 
return txwin;
-- 
2.7.4

[PATCH v3 01/18] powerpc/vas: init missing fields from [rt]xattr

[Sukadev Bhattiprolu]

Initialize a few missing window context fields from the window attributes
specified by the caller. These fields are currently set to their default
values by the caller (NX-842), but would be good to apply them anyway.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas-window.c | 6 ++
 1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
index 5aae845..cec7ab7 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -679,10 +679,13 @@ static void init_winctx_for_rxwin(struct vas_window 
*rxwin,
 
winctx->nx_win = rxattr->nx_win;
winctx->fault_win = rxattr->fault_win;
+   winctx->user_win = rxattr->user_win;
+   winctx->rej_no_credit = rxattr->rej_no_credit;
winctx->rx_word_mode = rxattr->rx_win_ord_mode;
winctx->tx_word_mode = rxattr->tx_win_ord_mode;
winctx->rx_wcred_mode = rxattr->rx_wcred_mode;
winctx->tx_wcred_mode = rxattr->tx_wcred_mode;
+   winctx->notify_early = rxattr->notify_early;
 
if (winctx->nx_win) {
winctx->data_stamp = true;
@@ -889,11 +892,14 @@ static void init_winctx_for_txwin(struct vas_window 
*txwin,
winctx->user_win = txattr->user_win;
winctx->nx_win = txwin->rxwin->nx_win;
winctx->pin_win = txattr->pin_win;
+   winctx->rej_no_credit = txattr->rej_no_credit;
+   winctx->rsvd_txbuf_enable = txattr->rsvd_txbuf_enable;
 
winctx->rx_wcred_mode = txattr->rx_wcred_mode;
winctx->tx_wcred_mode = txattr->tx_wcred_mode;
winctx->rx_word_mode = txattr->rx_win_ord_mode;
winctx->tx_word_mode = txattr->tx_win_ord_mode;
+   winctx->rsvd_txbuf_count = txattr->rsvd_txbuf_count;
 
if (winctx->nx_win) {
winctx->data_stamp = true;
-- 
2.7.4