Граф коммитов

663059 Коммитов

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Sagi Grimberg 7d9a5e7176 nvme-loop: increment request retries counter before requeuing
This way our max retry limit holds as well.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg e806666e25 nvme-rdma: increment request retries counter before requeuing
This way our max retry limit holds as well.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
James Smart 62eeacb0e0 nvme_fc: Clean up host fcpio done status handling
As Dan Carpenter pointed out: mixing 16-bit nvme status with 32-bit
error status from driver. Corrected comment on fcp request struct
status field, and converted done routine to explicitly set nvme status
codes for nvme status.

Signed-off-by: James Smart <james.smart@broadcom.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
James Smart c820ad4cda nvmet_fc: Clear SG list to avoid double frees
Clear SG list to avoid double frees of payload page list

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
James Smart f77fc87c37 nvme_fc: correct LS validation
LS validations shouldn't have been independent checks.

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
James Smart 4083aa986f nvmet_fc: Sync NVME LS reject reasons with spec
nvmet_fc: Sync NVME LS reject reasons with spec

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
James Smart 726a1080e5 nvme_fc: Add check of status_code in ERSP_IU
Add check of status_code in ERSP_IU

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
James Smart 0f222ccce3 nvme_fc: Sync FC-NVME header with standard
Update FC-NVME definitions to match FC-NVME r1.14 (16-020vB) plus
change voted in by 2/22 FC-NVME Adhoc (see HOSTID below).

Includes the following:
- Addition of "status_code" field to ERSP IU
- Addition of FC-NVME LS RJT reason_codes and reason_explanations
- CreateAssociation payload, HostID field shortened to 16 bytes

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg fd8563ced8 nvme-rdma: Support ctrl_loss_tmo
Before scheduling a reconnect attempt, check
nr_reconnects against max_reconnects, if not
exhausted (or max_reconnects is not -1), schedule
a reconnect attempts, otherwise schedule ctrl
removal.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 42a45274c2 nvme-fabrics: Allow ctrl loss timeout configuration
When a host sense that its controller session is damaged,
it tries to re-establish it periodically (reconnect every
reconnect_delay). It may very well be that the controller
is gone and never coming back, in this case the host will
try to reconnect forever.

Add a ctrl_loss_tmo to bound the number of reconnect attempts
to a specific controller (default to a reasonable 10 minutes).
The timeout configuration is actually translated into number of
reconnect attempts and not a schedule on its own but rather
divided with reconnect_delay. This is useful to prevent
racing flows of remove and reconnect, and it doesn't really
matter if we remove slightly sooner than what the user requested.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 7777bdedf3 nvme-rdma: get rid of local reconnect_delay
we already have it in opts.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 3b06837630 nvme-loop: retrieve iod from the cqe command_id
useful to validate that the we didn't mess up
the command_id.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg d89a39be5f nvme-loop: remove unneeded includes
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg c0e4a6f594 nvme-fc: fix module_init (theoretical) error path
If nvmf_register_transport happened to fail
(it can't, but theoretically) we leak memory.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg d19eef029d nvme-loop: fix module_init (theoretical) error path
if nvmf_register_transport happend to fail, we
need to nvmet_unregister_transport as well.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg a56c79cfd3 nvme-rdma: fix module_init (theoretical) error path
If nvmf_register_transport happened to fail
(it can't, but theoretically) we leak memory.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Max Gurtovoy 2ca0786d5a nvmet: use symbolic constants for log identifiers
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Parav Pandit 64a0ca88ea nvmet: Introduced helper routine for controller status check.
This patch introduces helper function for checking controller
status during admin and io command processing which returns u16
status. As to bring consistency on returning status, other
friend functions also now return u16 status instead of int
to match the spec.

As part of the theseerror log prints in also prints qid on
which command error occured.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Parav Pandit 4151dd9a58 nvmet: Fixed avoided printing nvmet: twice in error logs.
This patch avoids printing "nvmet:" twice in error logs as its already
coming through pr_fmt macro.

Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 4459e04297 iscsi-target: use generic inet_pton_with_scope
Instead of parsing address strings, use a generic
helper.

Acked-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 0928f9b4f1 nvme-rdma: use inet_pton_with_scope helper
Both the destination and the host addresses are now
parsed using inet_pton_with_scope helper. We also
get ipv6 (with address scopes support).

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 670c2a3ad5 nvmet-rdma: use generic inet_pton_with_scope
Instead of parsing address strings, use a generic
helper. This also adds ipv6 (with address scopes)
support.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg b1a951fe46 net/utils: generic inet_pton_with_scope helper
Several locations in the stack need to handle ipv4/ipv6
(with scope) and port strings conversion to sockaddr.
Add a helper that takes either AF_INET, AF_INET6 or
AF_UNSPEC (for wildcard) to centralize this handling.

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 297186d640 nvme-loop: remove some code duplication
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 782d820ca4 nvme-rdma: Give some more grace for rdma connection establishment
The target might be occupied with multiple hosts so lets
give it some more grace before failing the connection
establishment.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 777dc82395 nvmet-rdma: occasionally flush ongoing controller teardown
If we are attacked with establishments/teradowns we need to
make sure we do not consume too much system memory. Thus
let ongoing controller teardowns complete before accepting
new controller establishments.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg dc2ad16ab2 nvme-rdma: handle cpu unplug when re-establishing the controller
If a cpu unplug event has occured, we need to take the minimum
of the provided nr_io_queues and the number of online cpus,
otherwise we won't be able to connect them as blk-mq mapping
won't dispatch to those queues.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 8d61413db6 nvmet-rdma: Fix a possible uninitialized variable dereference
When handling a new recv command, we grab a new rsp resource and
check for the queue state being live. In case the queue is not in
live state, we simply restore the rsp back to the free list. However
in this flow we didn't set rsp->queue yet, so we cannot dereference it.

Instead, make sure to initialize rsp->queue (and other rsp members)
as soon as possible so we won't reference uninitialized variables.

Reported-by: Yi Zhang <yizhan@redhat.com>
Reported-by: Raju Rangoju <rajur@chelsio.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 427242ce99 nvmet: confirm sq percpu has scheduled and switched to atomic
percpu_ref_kill is not enough to prevent subsequent
percpu_ref_tryget_live from failing. Hence call
perfcpu_ref_kill_confirm to make it safe.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-04 09:48:23 -06:00
Sagi Grimberg 6ecda70ea9 nvme-loop: handle cpu unplug when re-establishing the controller
If a cpu unplug event has occured, we need to take the minimum
of the provided nr_io_queues and the number of online cpus,
otherwise we won't be able to connect them as blk-mq mapping
won't dispatch to those queues.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-04 09:44:43 -06:00
Sagi Grimberg d476983ea0 nvme-loop: fix a possible use-after-free when destroying the admin queue
we need to destroy the nvmet sq and let it finish gracefully
before continue to cleanup the queue.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-04 09:44:41 -06:00
Jens Axboe 8945927cb7 Merge branch 'nvme-4.11-rc' of git://git.infradead.org/nvme into for-linus
Sagi writes:

We have one spec mis-match fix from Roland and several sparse fixes from
Christoph.
2017-04-04 08:35:01 -06:00
Christoph Hellwig 793c7ed9d7 nvmet: fix byte swap in nvmet_parse_io_cmd
We need to do arithmetics after byte swapping, not before.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02 10:24:15 +03:00
Christoph Hellwig 78ce3daa7d nvmet: fix byte swap in nvmet_execute_write_zeroes
The length field in the Write Zeroes command is a 16-bit field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02 10:24:15 +03:00
Christoph Hellwig 5ac5fcc6c7 nvmet: add missing byte swap in nvmet_get_smart_log
In this case entirely harmless as it's all-ones, but still nice to
shut up sparse.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02 10:24:15 +03:00
Christoph Hellwig f1dd03a84d nvme: add missing byte swap in nvme_setup_discard
Fixes: b35ba01e ("nvme: support ranged discard requests")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02 10:24:15 +03:00
Roland Dreier bf17aa36c0 nvme: Correct NVMF enum values to match NVMe-oF rev 1.0
The enum values for QPTYPE, PRTYPE and CMS are off by 1 from the
values defined in figure 42 of the NVM Express over Fabrics 1.0:

    http://www.nvmexpress.org/wp-content/uploads/NVMe_over_Fabrics_1_0_Gold_20160605-1.pdf

Fix our enums to match the final spec.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-04-02 10:24:07 +03:00
Eric Biggers f363b089be blk-mq: constify struct blk_mq_ops
Constify all instances of blk_mq_ops, as they are never modified.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-31 08:28:58 -06:00
Jens Axboe db5bcf87bb null_blk: add blocking mode
This adds a new module parameter to null_blk, blocking. If set, null_blk
will set the BLK_MQ_F_BLOCKING flag, indicating that it sometimes/always
needs to block in its ->queue_rq() function.  The intent is to help find
regressions in blocking drivers, since not many of them exist.

If null_blk is loaded with submit_queues > 1 and blocking=1, this
shows the regression recently fixed by bf4907c05e.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30 13:44:26 -06:00
Jens Axboe bf4907c05e blk-mq: fix schedule-under-preempt for blocking drivers
Commit a4d907b6a3 unified the single and multi queue request handlers,
but in the process, it also screwed up the locking balance and calls
blk_mq_try_issue_directly() with the ctx preempt lock held. This is a
problem for drivers that have set BLK_MQ_F_BLOCKING, since now they
can't reliably sleep.

While in there, protect against similar issues in the future, by adding
a might_sleep() trigger in the BLOCKING path for direct issue or queue
run.

Reported-by: Josef Bacik <josef@toxicpanda.com>
Tested-by: Josef Bacik <josef@toxicpanda.com>
Fixes: a4d907b6a3 ("blk-mq: streamline blk_mq_make_request")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30 12:30:39 -06:00
Colin Ian King 47d752076a block/sed-opal: fix spelling mistake: "Lifcycle" -> "Lifecycle"
trivial fix to spelling mistake in pr_err error message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30 09:22:53 -06:00
Minchan Kim ac77a0c463 block: do not put mq context in blk_mq_alloc_request_hctx
In blk_mq_alloc_request_hctx, blk_mq_sched_get_request doesn't
get sw context so we don't need to put the context with
blk_mq_put_ctx. Unless, we will see preempt counter underflow.

Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30 08:13:23 -06:00
Minchan Kim 3e06eb3dac block: do not put mq context in blk_mq_alloc_request_hctx
In blk_mq_alloc_request_hctx, blk_mq_sched_get_request doesn't
get sw context so we don't need to put the context with
blk_mq_put_ctx. Unless, we will see preempt counter underflow.

Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-30 08:13:05 -06:00
Linus Torvalds 89970a04d7 Merge branch 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Pull thermal management fixes from Zhang Rui:

 - Fix a potential deadlock in cpu_cooling driver, which was introduced
   in 4.11-rc1. (Matthew Wilcox)

 - Fix the cpu_cooling and devfreq_cooling code to handle possible error
   return value from OPP calls, together with three minor fixes in the
   same patch series. (Viresh Kumar)

* 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
  thermal: cpu_cooling: Check OPP for errors
  thermal: cpu_cooling: Replace dev_warn with dev_err
  thermal: devfreq: Check OPP for errors
  thermal: devfreq_cooling: Replace dev_warn with dev_err
  thermal: devfreq: Simplify expression
  thermal: Fix potential deadlock in cpu_cooling
2017-03-29 19:59:49 -07:00
Linus Torvalds 806276b7f0 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "Five fixes for this series:

   - a fix from me to ensure that blk-mq drivers that terminate IO in
     their ->queue_rq() handler by returning QUEUE_ERROR don't stall
     with a scheduler enabled.

   - four nbd fixes from Josef and Ratna, fixing various problems that
     are critical enough to go in for this cycle. They have been well
     tested"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nbd: replace kill_bdev() with __invalidate_device()
  nbd: set queue timeout properly
  nbd: set rq->errors to actual error code
  nbd: handle ERESTARTSYS properly
  blk-mq: include errors in did_work calculation
2017-03-29 14:30:19 -07:00
Linus Torvalds 52b9c81680 Merge branch 'apw' (xfrm_user fixes)
Merge xfrm_user validation fixes from Andy Whitcroft:
 "Two patches we are applying to Ubuntu for XFRM_MSG_NEWAE validation
  issue reported by ZDI.

  The first of these is the primary fix, and the second is for a more
  theoretical issue that Kees pointed out when reviewing the first"

* emailed patches from Andy Whitcroft <apw@canonical.com>:
  xfrm_user: validate XFRM_MSG_NEWAE incoming ESN size harder
  xfrm_user: validate XFRM_MSG_NEWAE XFRMA_REPLAY_ESN_VAL replay_window
2017-03-29 13:26:22 -07:00
Jens Axboe 3e8a7069b9 blk-mq: include errors in did_work calculation
Currently we return true in blk_mq_dispatch_rq_list() if we queued IO
successfully, but we really want to return whether or not the we made
progress. Progress includes if we got an error return.  If we don't,
this can lead to a hang in blk_mq_sched_dispatch_requests() when a
driver is draining IO by returning BLK_MQ_QUEUE_ERROR instead of
manually ending the IO in error and return BLK_MQ_QUEUE_OK.

Tested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29 13:21:13 -06:00
Josef Bacik b58e176914 block-mq: don't re-queue if we get a queue error
When try to issue a request directly and we fail we will requeue the
request, but call blk_mq_end_request() as well.  This leads to the
completed request being on a queuelist and getting ended twice, which
causes list corruption in schedulers and other shenanigans.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29 13:18:18 -06:00
Tahsin Erdogan 457e490f2b blkcg: allocate struct blkcg_gq outside request queue spinlock
blkg_conf_prep() currently calls blkg_lookup_create() while holding
request queue spinlock. This means allocating memory for struct
blkcg_gq has to be made non-blocking. This causes occasional -ENOMEM
failures in call paths like below:

  pcpu_alloc+0x68f/0x710
  __alloc_percpu_gfp+0xd/0x10
  __percpu_counter_init+0x55/0xc0
  cfq_pd_alloc+0x3b2/0x4e0
  blkg_alloc+0x187/0x230
  blkg_create+0x489/0x670
  blkg_lookup_create+0x9a/0x230
  blkg_conf_prep+0x1fb/0x240
  __cfqg_set_weight_device.isra.105+0x5c/0x180
  cfq_set_weight_on_dfl+0x69/0xc0
  cgroup_file_write+0x39/0x1c0
  kernfs_fop_write+0x13f/0x1d0
  __vfs_write+0x23/0x120
  vfs_write+0xc2/0x1f0
  SyS_write+0x44/0xb0
  entry_SYSCALL_64_fastpath+0x18/0xad

In the code path above, percpu allocator cannot call vmalloc() due to
queue spinlock.

A failure in this call path gives grief to tools which are trying to
configure io weights. We see occasional failures happen shortly after
reboots even when system is not under any memory pressure. Machines
with a lot of cpus are more vulnerable to this condition.

Do struct blkcg_gq allocations outside the queue spinlock to allow
blocking during memory allocations.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-29 11:27:19 -06:00
Jens Axboe d708f0d502 Revert "blkcg: allocate struct blkcg_gq outside request queue spinlock"
I inadvertently applied the v5 version of this patch, whereas
the agreed upon version was v5. Revert this one so we can apply
the right one.

This reverts commit 7fc6b87a9f.
2017-03-29 11:25:48 -06:00