diff options
| author | Jens Axboe <axboe@kernel.dk> | 2021-12-14 07:03:24 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-12-14 20:08:05 -0700 |
| commit | cb2ac2912a9ca7d3d26291c511939a41361d2d83 (patch) | |
| tree | 5e7397cf98c33d5ea4287116aeded901fc7d19db /block | |
| parent | edaa26334c117a584add6053f48d63a988d25a6e (diff) | |
block: reduce kblockd_mod_delayed_work_on() CPU consumption
Dexuan reports that he's seeing spikes of very heavy CPU utilization when
running 24 disks and using the 'none' scheduler. This happens off the
sched restart path, because SCSI requires the queue to be restarted async,
and hence we're hammering on mod_delayed_work_on() to ensure that the work
item gets run appropriately.
Avoid hammering on the timer and just use queue_work_on() if no delay
has been specified.
Reported-and-tested-by: Dexuan Cui <decui@microsoft.com>
Link: https://lore.kernel.org/linux-block/BYAPR21MB1270C598ED214C0490F47400BF719@BYAPR21MB1270.namprd21.prod.outlook.com/
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-core.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 1378d084c770..c1833f95cb97 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1484,6 +1484,8 @@ EXPORT_SYMBOL(kblockd_schedule_work); int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay) { + if (!delay) + return queue_work_on(cpu, kblockd_workqueue, &dwork->work); return mod_delayed_work_on(cpu, kblockd_workqueue, dwork, delay); } EXPORT_SYMBOL(kblockd_mod_delayed_work_on); |