| Message ID | 20250207091942.3966756-1-zhaoyang.huang@unisoc.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | driver: block: release the lo_work_lock before queue_work | expand |
On Fri, Feb 7, 2025 at 5:20 PM zhaoyang.huang <zhaoyang.huang@unisoc.com> wrote: > > From: Zhaoyang Huang <zhaoyang.huang@unisoc.com> > > queue_work could spin on wq->cpu_pwq->pool->lock which could lead to > concurrent loop_process_work failed on lo_work_lock contention and > increase the request latency. Remove this combination by moving the > lock release ahead of queue_work. > > Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com> > --- > drivers/block/loop.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/block/loop.c b/drivers/block/loop.c > index 8f6761c27c68..33e31cd95953 100644 > --- a/drivers/block/loop.c > +++ b/drivers/block/loop.c > @@ -890,8 +890,8 @@ static void loop_queue_work(struct loop_device *lo, struct loop_cmd *cmd) > cmd_list = &lo->rootcg_cmd_list; > } > list_add_tail(&cmd->list_entry, cmd_list); > - queue_work(lo->workqueue, work); > spin_unlock_irq(&lo->lo_work_lock); > + queue_work(lo->workqueue, work); > } Reviewed-by: Ming Lei <ming.lei@redhat.com>
On Fri, 07 Feb 2025 17:19:42 +0800, zhaoyang.huang wrote: > queue_work could spin on wq->cpu_pwq->pool->lock which could lead to > concurrent loop_process_work failed on lo_work_lock contention and > increase the request latency. Remove this combination by moving the > lock release ahead of queue_work. > > Applied, thanks! [1/1] driver: block: release the lo_work_lock before queue_work commit: 3bee991f2b68175c828dc3f9c26367fe1827319a Best regards,
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 8f6761c27c68..33e31cd95953 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -890,8 +890,8 @@ static void loop_queue_work(struct loop_device *lo, struct loop_cmd *cmd) cmd_list = &lo->rootcg_cmd_list; } list_add_tail(&cmd->list_entry, cmd_list); - queue_work(lo->workqueue, work); spin_unlock_irq(&lo->lo_work_lock); + queue_work(lo->workqueue, work); } static void loop_set_timer(struct loop_device *lo)