Commit fbcc8183 authored by Jiang Biao's avatar Jiang Biao Committed by Linus Torvalds
Browse files

mm/vmstat.c: erase latency in vmstat_shepherd 

Many 100us+ latencies have been deteceted in vmstat_shepherd() on CPX
platform which has 208 logic cpus.  And vmstat_shepherd is queued every
second, which could make the case worse.

Add schedule point in vmstat_shepherd() to erase the latency.

Link: https://lkml.kernel.org/r/20210111035526.1511-1-benbjiang@tencent.com


Signed-off-by: default avatarJiang Biao <benbjiang@tencent.com>
Reported-by: default avatarBin Lai <robinlai@tencent.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 629484ae

mm/vmstat.c

+2 −0
Original line number Diff line number Diff line
@@ -1980,6 +1980,8 @@ static void vmstat_shepherd(struct work_struct *w) 


		if (!delayed_work_pending(dw) && need_update(cpu))

			queue_delayed_work_on(cpu, mm_percpu_wq, dw, 0);



		cond_resched();

	}

	put_online_cpus();