From: Jiang Biao <benbjiang@xxxxxxxxxxx> 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. Signed-off-by: Jiang Biao <benbjiang@xxxxxxxxxxx> Reported-by: Bin Lai <robinlai@xxxxxxxxxxx> --- mm/vmstat.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/vmstat.c b/mm/vmstat.c index f8942160fc95..b538199883b5 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1953,6 +1953,8 @@ 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(); -- 2.21.0
