Re: [Xen-devel] [PATCH v12 1/6] IOMMU: add a timeout parameter for device IOTLB invalidation
On June 27, 2016 4:29 PM, Jan Beulich wrote: > >>> On 27.06.16 at 10:19, wrote: > > On June 27, 2016 4:03 PM, Jan Beulich wrote: > >> >>> On 24.06.16 at 07:51, wrote: > >> > From: Quan Xu > >> > > >> > The parameter 'iommu_dev_iotlb_timeout' specifies the timeout of > >> > device IOTLB invalidation in milliseconds. By default, the timeout > >> > is > >> > 1000 milliseconds, which can be boot-time changed. > >> > > >> > We also confirmed with VT-d hardware team that 1 milliseconds is > >> > large enough for VT-d IOMMU internal invalidation. > >> > > >> > the existing panic() is eliminated and we bubble up the timeout of > >> > device IOTLB invalidation for further processing, as the PCI-e > >> > Address Translation Services (ATS) mandates a timeout of > >> > 60 seconds for device IOTLB invalidation. Obviously we can't spin > >> > for > >> > 60 seconds or otherwise Xen hypervisor hangs. > >> > > >> > Add a __must_check annotation. The followup patch titled 'VT-d > >> > IOTLB/Context/IEC flush issue' addresses the __mustcheck. > >> > That is the other callers of this routine (two or three levels up) > >> > ignore the return code. This patch does not address this but the > >> > other does. > >> > >> The patch itself looks okay, > > > > Jan, thanks for your review. > > > >> but I'm confused by this paragraph: > >> There's no patch with the named title later in this series. And > >> having gone through this patch I also don't see what remains to be > >> addressed wrt the __must_check-s getting added here. > > > > This paragraph was added from a few rounds ago. I will drop it in next > > version. > > Well, if dropping this paragraph is all that's needed, Yes, > I can do this while > committing: Patches 1-3 appear to be ready to go in. > Ah, that's great. Thanks. Quan ___ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Re: [Xen-devel] [PATCH v12 1/6] IOMMU: add a timeout parameter for device IOTLB invalidation
>>> On 27.06.16 at 10:19, wrote: > On June 27, 2016 4:03 PM, Jan Beulich wrote: >> >>> On 24.06.16 at 07:51, wrote: >> > From: Quan Xu >> > >> > The parameter 'iommu_dev_iotlb_timeout' specifies the timeout of >> > device IOTLB invalidation in milliseconds. By default, the timeout is >> > 1000 milliseconds, which can be boot-time changed. >> > >> > We also confirmed with VT-d hardware team that 1 milliseconds is large >> > enough for VT-d IOMMU internal invalidation. >> > >> > the existing panic() is eliminated and we bubble up the timeout of >> > device IOTLB invalidation for further processing, as the PCI-e Address >> > Translation Services (ATS) mandates a timeout of >> > 60 seconds for device IOTLB invalidation. Obviously we can't spin for >> > 60 seconds or otherwise Xen hypervisor hangs. >> > >> > Add a __must_check annotation. The followup patch titled 'VT-d >> > IOTLB/Context/IEC flush issue' addresses the __mustcheck. >> > That is the other callers of this routine (two or three levels up) >> > ignore the return code. This patch does not address this but the other >> > does. >> >> The patch itself looks okay, > > Jan, thanks for your review. > >> but I'm confused by this paragraph: >> There's no patch with the named title later in this series. And having gone >> through this patch I also don't see what remains to be addressed wrt the >> __must_check-s getting added here. > > This paragraph was added from a few rounds ago. I will drop it in next > version. Well, if dropping this paragraph is all that's needed, I can do this while committing: Patches 1-3 appear to be ready to go in. Jan ___ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Re: [Xen-devel] [PATCH v12 1/6] IOMMU: add a timeout parameter for device IOTLB invalidation
On June 27, 2016 4:03 PM, Jan Beulich wrote: > >>> On 24.06.16 at 07:51, wrote: > > From: Quan Xu > > > > The parameter 'iommu_dev_iotlb_timeout' specifies the timeout of > > device IOTLB invalidation in milliseconds. By default, the timeout is > > 1000 milliseconds, which can be boot-time changed. > > > > We also confirmed with VT-d hardware team that 1 milliseconds is large > > enough for VT-d IOMMU internal invalidation. > > > > the existing panic() is eliminated and we bubble up the timeout of > > device IOTLB invalidation for further processing, as the PCI-e Address > > Translation Services (ATS) mandates a timeout of > > 60 seconds for device IOTLB invalidation. Obviously we can't spin for > > 60 seconds or otherwise Xen hypervisor hangs. > > > > Add a __must_check annotation. The followup patch titled 'VT-d > > IOTLB/Context/IEC flush issue' addresses the __mustcheck. > > That is the other callers of this routine (two or three levels up) > > ignore the return code. This patch does not address this but the other > > does. > > The patch itself looks okay, Jan, thanks for your review. > but I'm confused by this paragraph: > There's no patch with the named title later in this series. And having gone > through this patch I also don't see what remains to be addressed wrt the > __must_check-s getting added here. > This paragraph was added from a few rounds ago. I will drop it in next version. Quan ___ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Re: [Xen-devel] [PATCH v12 1/6] IOMMU: add a timeout parameter for device IOTLB invalidation
>>> On 24.06.16 at 07:51, wrote: > From: Quan Xu > > The parameter 'iommu_dev_iotlb_timeout' specifies the timeout > of device IOTLB invalidation in milliseconds. By default, the > timeout is 1000 milliseconds, which can be boot-time changed. > > We also confirmed with VT-d hardware team that 1 milliseconds > is large enough for VT-d IOMMU internal invalidation. > > the existing panic() is eliminated and we bubble up the timeout > of device IOTLB invalidation for further processing, as the > PCI-e Address Translation Services (ATS) mandates a timeout of > 60 seconds for device IOTLB invalidation. Obviously we can't > spin for 60 seconds or otherwise Xen hypervisor hangs. > > Add a __must_check annotation. The followup patch titled > 'VT-d IOTLB/Context/IEC flush issue' addresses the __mustcheck. > That is the other callers of this routine (two or three levels up) > ignore the return code. This patch does not address this but the > other does. The patch itself looks okay, but I'm confused by this paragraph: There's no patch with the named title later in this series. And having gone through this patch I also don't see what remains to be addressed wrt the __must_check-s getting added here. Jan ___ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Re: [Xen-devel] [PATCH v12 1/6] IOMMU: add a timeout parameter for device IOTLB invalidation
> From: Xu, Quan > Sent: Friday, June 24, 2016 1:52 PM > > From: Quan Xu > > The parameter 'iommu_dev_iotlb_timeout' specifies the timeout > of device IOTLB invalidation in milliseconds. By default, the > timeout is 1000 milliseconds, which can be boot-time changed. > > We also confirmed with VT-d hardware team that 1 milliseconds > is large enough for VT-d IOMMU internal invalidation. > > the existing panic() is eliminated and we bubble up the timeout > of device IOTLB invalidation for further processing, as the > PCI-e Address Translation Services (ATS) mandates a timeout of > 60 seconds for device IOTLB invalidation. Obviously we can't > spin for 60 seconds or otherwise Xen hypervisor hangs. > > Add a __must_check annotation. The followup patch titled > 'VT-d IOTLB/Context/IEC flush issue' addresses the __mustcheck. > That is the other callers of this routine (two or three levels up) > ignore the return code. This patch does not address this but the > other does. > > Signed-off-by: Quan Xu > Acked-by: Kevin Tian ___ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
[Xen-devel] [PATCH v12 1/6] IOMMU: add a timeout parameter for device IOTLB invalidation
From: Quan Xu
The parameter 'iommu_dev_iotlb_timeout' specifies the timeout
of device IOTLB invalidation in milliseconds. By default, the
timeout is 1000 milliseconds, which can be boot-time changed.
We also confirmed with VT-d hardware team that 1 milliseconds
is large enough for VT-d IOMMU internal invalidation.
the existing panic() is eliminated and we bubble up the timeout
of device IOTLB invalidation for further processing, as the
PCI-e Address Translation Services (ATS) mandates a timeout of
60 seconds for device IOTLB invalidation. Obviously we can't
spin for 60 seconds or otherwise Xen hypervisor hangs.
Add a __must_check annotation. The followup patch titled
'VT-d IOTLB/Context/IEC flush issue' addresses the __mustcheck.
That is the other callers of this routine (two or three levels up)
ignore the return code. This patch does not address this but the
other does.
Signed-off-by: Quan Xu
CC: Julien Grall
CC: Jan Beulich
CC: Kevin Tian
CC: Feng Wu
CC: Suravee Suthikulpanit
---
v12:
1. enhance commit message.
2. change timeout from 1ms to 1000ms.
3. change IOMMU_QI_TIMEOUT to VTD_QI_TIMEOUT, with VTD_QI_TIMEOUT
having its MILLISECS() dropped.
4. enhance the whole expression of 'timeout = ...'
5. drop a blank line that doesn't belong here.
---
docs/misc/xen-command-line.markdown | 9 +
xen/drivers/passthrough/iommu.c | 3 +++
xen/drivers/passthrough/vtd/qinval.c | 32 +---
xen/include/xen/iommu.h | 2 ++
4 files changed, 35 insertions(+), 11 deletions(-)
diff --git a/docs/misc/xen-command-line.markdown
b/docs/misc/xen-command-line.markdown
index 7a271c0..0046f0d 100644
--- a/docs/misc/xen-command-line.markdown
+++ b/docs/misc/xen-command-line.markdown
@@ -1015,6 +1015,15 @@ debug hypervisor only).
>> Enable IOMMU debugging code (implies `verbose`).
+### iommu\_dev\_iotlb\_timeout
+> `= `
+
+> Default: `1000`
+
+Specify the timeout of the device IOTLB invalidation in milliseconds.
+By default, the timeout is 1000 ms. When you see error 'Queue invalidate
+wait descriptor timed out', try increasing this value.
+
### iommu\_inclusive\_mapping (VT-d)
> `= `
diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index ef80b3c..7656aeb 100644
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -24,6 +24,9 @@
static void parse_iommu_param(char *s);
static void iommu_dump_p2m_table(unsigned char key);
+unsigned int __read_mostly iommu_dev_iotlb_timeout = 1000;
+integer_param("iommu_dev_iotlb_timeout", iommu_dev_iotlb_timeout);
+
/*
* The 'iommu' parameter enables the IOMMU. Optional comma separated
* value may contain:
diff --git a/xen/drivers/passthrough/vtd/qinval.c
b/xen/drivers/passthrough/vtd/qinval.c
index aa7841a..4788d5f 100644
--- a/xen/drivers/passthrough/vtd/qinval.c
+++ b/xen/drivers/passthrough/vtd/qinval.c
@@ -28,6 +28,8 @@
#include "vtd.h"
#include "extern.h"
+#define VTD_QI_TIMEOUT 1
+
static void print_qi_regs(struct iommu *iommu)
{
u64 val;
@@ -130,10 +132,10 @@ static void queue_invalidate_iotlb(struct iommu *iommu,
spin_unlock_irqrestore(&iommu->register_lock, flags);
}
-static int queue_invalidate_wait(struct iommu *iommu,
-u8 iflag, u8 sw, u8 fn)
+static int __must_check queue_invalidate_wait(struct iommu *iommu,
+ u8 iflag, u8 sw, u8 fn,
+ bool_t flush_dev_iotlb)
{
-s_time_t start_time;
volatile u32 poll_slot = QINVAL_STAT_INIT;
unsigned int index;
unsigned long flags;
@@ -163,14 +165,20 @@ static int queue_invalidate_wait(struct iommu *iommu,
/* Now we don't support interrupt method */
if ( sw )
{
+s_time_t timeout;
+
/* In case all wait descriptor writes to same addr with same data */
-start_time = NOW();
+timeout = NOW() + MILLISECS(flush_dev_iotlb ?
+iommu_dev_iotlb_timeout : VTD_QI_TIMEOUT);
+
while ( poll_slot != QINVAL_STAT_DONE )
{
-if ( NOW() > (start_time + DMAR_OPERATION_TIMEOUT) )
+if ( NOW() > timeout )
{
print_qi_regs(iommu);
-panic("queue invalidate wait descriptor was not executed");
+printk(XENLOG_WARNING VTDPREFIX
+ " Queue invalidate wait descriptor timed out\n");
+return -ETIMEDOUT;
}
cpu_relax();
}
@@ -180,12 +188,14 @@ static int queue_invalidate_wait(struct iommu *iommu,
return -EOPNOTSUPP;
}
-static int invalidate_sync(struct iommu *iommu)
+static int __must_check invalidate_sync(struct iommu *iommu,
+bool_t flush_dev_iotlb)
{
struct qi_ctrl *qi_ctrl = iommu_qi_ctrl(iommu);
if ( qi_ctrl->qinval_maddr )
-return queue_invalidate_wait(iommu, 0, 1, 1);
