Re: [PATCH 05/11] fs: add iterate_supers_excl() and iterate_supers_reverse_excl()

On Thu, Nov 30, 2017 at 2:34 AM, Dave Chinner wrote: > On Thu, Nov 30, 2017 at 12:48:15AM +0100, Rafael J. Wysocki wrote: >> On Thu, Nov 30, 2017 at 12:23 AM, Luis R. Rodriguez >> wrote: >> > There are use cases where we wish to traverse the superblock

Re: [PATCH 05/11] fs: add iterate_supers_excl() and iterate_supers_reverse_excl()

On Thu, Nov 30, 2017 at 12:48:15AM +0100, Rafael J. Wysocki wrote: > On Thu, Nov 30, 2017 at 12:23 AM, Luis R. Rodriguez wrote: > > There are use cases where we wish to traverse the superblock list > > but also capture errors, and in which case we want to avoid having > > our

Re: [PATCH 05/11] fs: add iterate_supers_excl() and iterate_supers_reverse_excl()

On Thu, Nov 30, 2017 at 12:48:15AM +0100, Rafael J. Wysocki wrote: > On Thu, Nov 30, 2017 at 12:23 AM, Luis R. Rodriguez wrote: > > +int iterate_supers_excl(int (*f)(struct super_block *, void *), void *arg) > > +{ > > + struct super_block *sb, *p = NULL; > > + int

[PATCH V3] block: drain queue before waiting for q_usage_counter becoming zero

Now we track legacy requests with .q_usage_counter in commit 055f6e18e08f ("block: Make q_usage_counter also track legacy requests"), but that commit never runs and drains legacy queue before waiting for this counter becoming zero, then IO hang is caused in the test of pulling disk during IO.

Re: [PATCH 05/11] fs: add iterate_supers_excl() and iterate_supers_reverse_excl()

On Thu, Nov 30, 2017 at 12:23 AM, Luis R. Rodriguez wrote: > There are use cases where we wish to traverse the superblock list > but also capture errors, and in which case we want to avoid having > our callers issue a lock themselves since we can do the locking for > the

[PATCH 00/11] fs: use freeze_fs on suspend/hibernate

[3] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?h=20171129-fs-freeze-cleanup [4] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/log/?h=20171129-fs-freeze-cleanup Luis R. Rodriguez (11): fs: provide unlocked helper for freeze_super() fs

[PATCH 03/11] fs: add frozen sb state helpers

The question of whether or not a superblock is frozen needs to be augmented in the future to account for differences between a user initiated freeze and a kernel initiated freeze done automatically on behalf of the kernel. Provide helpers so that these can be used instead so that we don't have to

[PATCH 04/11] fs: distinguish between user initiated freeze and kernel initiated freeze

Userspace can initiate a freeze call using ioctls. If the kernel decides to freeze a filesystem later it must be able to distinguish if userspace had initiated the freeze, so that it does not unfreeze it later automatically on resume. Likewise if the kernel is initiating a freeze on its own it

[PATCH 01/11] fs: provide unlocked helper for freeze_super()

freeze_super() holds a write lock, however we wish to also enable callers which already hold the write lock. To do this provide a helper and make freeze_super() use it. This way, all that freeze_super() does now is lock handling and active count management. This change has no functional changes.

[PATCH 02/11] fs: provide unlocked helper thaw_super()

thaw_super() hold a write lock, however we wish to also enable callers which already hold the write lock. To do this provide a helper and make thaw_super() use it. This way, all that thaw_super() does now is lock handling and active count management. This change has no functional changes.

[PATCH 05/11] fs: add iterate_supers_excl() and iterate_supers_reverse_excl()

There are use cases where we wish to traverse the superblock list but also capture errors, and in which case we want to avoid having our callers issue a lock themselves since we can do the locking for the callers. Provide a iterate_supers_excl() which calls a function with the write lock held. If

[PATCH 07/11] xfs: remove not needed freezing calls

This removes superflous freezer calls as they are no longer needed as the VFS now performs filesystem freezing/thaw if the filesystem has support for it. The following Coccinelle rule was used as follows: spatch --sp-file fs-freeze-cleanup.cocci --in-place fs/$FS/ @ has_freeze_fs @ identifier

[PATCH 06/11] fs: freeze on suspend and thaw on resume

This uses the existing filesystem freeze and thaw callbacks to freeze each filesystem on suspend/hibernation and thaw upon resume. This is needed so that we properly really stop IO in flight without races after userspace has been frozen. Without this we rely on kthread freezing and its semantics

[PATCH 09/11] f2fs: remove not needed freezing calls

This removes superflous freezer calls as they are no longer needed as the VFS now performs filesystem freezing/thaw if the filesystem has support for it. The following Coccinelle rule was used as follows: spatch --sp-file fs-freeze-cleanup.cocci --in-place fs/$FS/ @ has_freeze_fs @ identifier

[PATCH 08/11] ext4: remove not needed freezing calls

This removes superflous freezer calls as they are no longer needed as the VFS now performs filesystem freezing/thaw if the filesystem has support for it. The following Coccinelle rule was used as follows: spatch --sp-file fs-freeze-cleanup.cocci --in-place fs/$FS/ @ has_freeze_fs @ identifier

[PATCH 10/11] nilfs2: remove not needed freezing calls

This removes superflous freezer calls as they are no longer needed as the VFS now performs filesystem freezing/thaw if the filesystem has support for it. The following Coccinelle rule was used as follows: spatch --sp-file fs-freeze-cleanup.cocci --in-place fs/$FS/ @ has_freeze_fs @ identifier

[PATCH 11/11] jfs: remove not needed freezing calls

This removes superflous freezer calls as they are no longer needed as the VFS now performs filesystem freezing/thaw if the filesystem has support for it. The following Coccinelle rule was used as follows: spatch --sp-file fs-freeze-cleanup.cocci --in-place fs/$FS/ @ has_freeze_fs @ identifier

Re: [RFC 5/5] pm: remove kernel thread freezing

On Wed, Oct 04, 2017 at 01:03:54AM +, Bart Van Assche wrote: > On Wed, 2017-10-04 at 02:47 +0200, Luis R. Rodriguez wrote: > > 3) Lookup for kthreads which seem to generate IO -- address / review if > > removal of the freezer API can be done somehow with a quescing. This > > is

Re: [PATCH] [RFC] um: Convert ubd driver to blk-mq

On Sun, Nov 26, 2017 at 02:10:53PM +0100, Richard Weinberger wrote: > MAX_SG is 64, used for blk_queue_max_segments(). This comes from > a0044bdf60c2 ("uml: batch I/O requests"). Is this still a good/sane > value for blk-mq? blk-mq itself doesn't change the tradeoff. > The driver does IO

Re: 4.14: WARNING: CPU: 4 PID: 2895 at block/blk-mq.c:1144 with virtio-blk (also 4.12 stable)

On 11/29/2017 08:18 PM, Christian Borntraeger wrote: > Works fine under KVM with virtio-blk, but still hangs during boot in an LPAR. > FWIW, the system not only has scsi disks via fcp but also DASDs as a boot > disk. > Seems that this is the place where the system stops. (see the sysrq-t output

Re: 4.14: WARNING: CPU: 4 PID: 2895 at block/blk-mq.c:1144 with virtio-blk (also 4.12 stable)

Works fine under KVM with virtio-blk, but still hangs during boot in an LPAR. FWIW, the system not only has scsi disks via fcp but also DASDs as a boot disk. Seems that this is the place where the system stops. (see the sysrq-t output at the bottom). Message "[0.247484] Linux version

Re: [GIT PULL] nvme fixes for Linux 4.15

On 11/29/2017 09:16 AM, Christoph Hellwig wrote: > Hi Jens, > > a few more nvme updates for 4.15. A single small PCIe fix, and a number > of patches for RDMA that are a little larger than what I'd like to see > for -rc2, but they fix important issues seen in the wild. Looks good to me, pulled.

[PATCH V15 02/22] mmc: block: Simplify cleaning up the queue

Use blk_cleanup_queue() to shutdown the queue when the driver is removed, and instead get an extra reference to the queue to prevent the queue being freed before the final mmc_blk_put(). Signed-off-by: Adrian Hunter --- drivers/mmc/core/block.c | 17 -

[PATCH V15 03/22] mmc: core: Make mmc_pre_req() and mmc_post_req() available

Make mmc_pre_req() and mmc_post_req() available to the card drivers. Later patches will make use of this. Signed-off-by: Adrian Hunter --- drivers/mmc/core/core.c | 31 --- drivers/mmc/core/core.h | 31 +++ 2 files

[PATCH V15 05/22] mmc: core: Add parameter use_blk_mq

Until mmc has blk-mq support fully implemented and tested, add a parameter use_blk_mq, set to true if config option MMC_MQ_DEFAULT is selected, which it is by default. Signed-off-by: Adrian Hunter --- drivers/mmc/Kconfig | 10 ++ drivers/mmc/core/core.c |

[PATCH V15 06/22] mmc: block: Add blk-mq support

Define and use a blk-mq queue. Discards and flushes are processed synchronously, but reads and writes asynchronously. In order to support slow DMA unmapping, DMA unmapping is not done until after the next request is started. That means the request is not completed until then. If there is no next

[PATCH V15 07/22] mmc: block: Add CQE support

Add CQE support to the block driver, including: - optionally using DCMD for flush requests - "manually" issuing discard requests - issuing read / write requests to the CQE - supporting block-layer timeouts - handling recovery - supporting re-tuning CQE offers 25% - 50%

[PATCH V15 10/22] mmc: block: blk-mq: Add support for direct completion

For blk-mq, add support for completing requests directly in the ->done callback. That means that error handling and urgent background operations must be handled by recovery_work in that case. Signed-off-by: Adrian Hunter --- drivers/mmc/core/block.c | 129

[PATCH V15 11/22] mmc: block: blk-mq: Separate card polling from recovery

Recovery is simpler to understand if it is only used for errors. Create a separate function for card polling. Signed-off-by: Adrian Hunter --- drivers/mmc/core/block.c | 29 - 1 file changed, 28 insertions(+), 1 deletion(-) diff --git

[PATCH V15 13/22] mmc: block: blk-mq: Check error bits and save the exception bit when polling card busy

Check error bits and save the exception bit when polling card busy. Signed-off-by: Adrian Hunter --- drivers/mmc/core/block.c | 37 - 1 file changed, 28 insertions(+), 9 deletions(-) diff --git a/drivers/mmc/core/block.c

[PATCH V15 14/22] mmc: block: Check the timeout correctly in card_busy_detect()

Pedantically, ensure the status is checked for the last time after the full timeout has passed. Signed-off-by: Adrian Hunter --- drivers/mmc/core/block.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/core/block.c

[PATCH V15 16/22] mmc: block: Add timeout_clks when calculating timeout

According to the specification, total access time is derived from both TAAC and NSAC, which means the timeout should add both timeout_ns and timeout_clks. Host drivers do that, so make the block driver do that too. Signed-off-by: Adrian Hunter ---

[PATCH V15 17/22] mmc: block: Reduce polling timeout from 10 minutes to 10 seconds

Set a 10 second timeout for polling write request busy state. Note, mmc core is setting a 3 second timeout for SD cards, and SDHCI has long had a 10 second software timer to timeout the whole request, so 10 seconds should be ample. Signed-off-by: Adrian Hunter ---

[PATCH V15 18/22] mmc: block: blk-mq: Stop using legacy recovery

There are only a few things the recovery needs to do. Primarily, it just needs to: Determine the number of bytes transferred Get the card back to transfer state Determine whether to retry There are also a couple of additional features: Reset the card before the

[PATCH V15 19/22] mmc: mmc_test: Do not use mmc_start_areq() anymore

The block driver's blk-mq paths do not use mmc_start_areq(). In order to remove mmc_start_areq() entirely, start by removing it from mmc_test. Signed-off-by: Adrian Hunter --- drivers/mmc/core/mmc_test.c | 122 1 file

[PATCH V15 20/22] mmc: core: Remove option not to use blk-mq

Remove config option MMC_MQ_DEFAULT and parameter mmc_use_blk_mq, so that blk-mq must be used always. Signed-off-by: Adrian Hunter --- drivers/mmc/Kconfig | 10 -- drivers/mmc/core/core.c | 7 --- drivers/mmc/core/core.h | 2 -- drivers/mmc/core/host.c

[PATCH V15 21/22] mmc: block: Remove code no longer needed after the switch to blk-mq

Remove code no longer needed after the switch to blk-mq. Signed-off-by: Adrian Hunter --- drivers/mmc/core/block.c | 723 +-- drivers/mmc/core/block.h | 2 - drivers/mmc/core/queue.c | 240 +---

[PATCH V15 22/22] mmc: core: Remove code no longer needed after the switch to blk-mq

Remove code no longer needed after the switch to blk-mq. Signed-off-by: Adrian Hunter --- drivers/mmc/core/bus.c | 2 - drivers/mmc/core/core.c | 185 +-- drivers/mmc/core/core.h | 8 -- drivers/mmc/core/host.h | 5

Re: [PATCH 00/12 v5] Multiqueue for MMC/SD

On Wed, Nov 15, 2017 at 2:50 PM, Adrian Hunter wrote: > On 14/11/17 23:17, Linus Walleij wrote: >> We have the following risk factors: >> >> - Observed performance degradation of 1% (on x86 SDHI I guess) >> - The kernel crashes if SD card is removed (both patch sets) > >