diff options
author | Yunfeng Ye <yeyunfeng@huawei.com> | 2020-11-19 14:21:25 +0800 |
---|---|---|
committer | Tejun Heo <tj@kernel.org> | 2020-11-25 17:10:28 -0500 |
commit | 01341fbd0d8d4e717fc1231cdffe00343088ce0b (patch) | |
tree | ff3811c2c56f56b94ec7687bf943454112591fda /kernel | |
parent | 127c501a03d5db8b833e953728d3bcf53c8832a9 (diff) |
workqueue: Kick a worker based on the actual activation of delayed works
In realtime scenario, We do not want to have interference on the
isolated cpu cores. but when invoking alloc_workqueue() for percpu wq
on the housekeeping cpu, it kick a kworker on the isolated cpu.
alloc_workqueue
pwq_adjust_max_active
wake_up_worker
The comment in pwq_adjust_max_active() said:
"Need to kick a worker after thawed or an unbound wq's
max_active is bumped"
So it is unnecessary to kick a kworker for percpu's wq when invoking
alloc_workqueue(). this patch only kick a worker based on the actual
activation of delayed works.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/workqueue.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 437935e7a199..0695c7895c89 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -3728,17 +3728,24 @@ static void pwq_adjust_max_active(struct pool_workqueue *pwq) * is updated and visible. */ if (!freezable || !workqueue_freezing) { + bool kick = false; + pwq->max_active = wq->saved_max_active; while (!list_empty(&pwq->delayed_works) && - pwq->nr_active < pwq->max_active) + pwq->nr_active < pwq->max_active) { pwq_activate_first_delayed(pwq); + kick = true; + } /* * Need to kick a worker after thawed or an unbound wq's - * max_active is bumped. It's a slow path. Do it always. + * max_active is bumped. In realtime scenarios, always kicking a + * worker will cause interference on the isolated cpu cores, so + * let's kick iff work items were activated. */ - wake_up_worker(pwq->pool); + if (kick) + wake_up_worker(pwq->pool); } else { pwq->max_active = 0; } |