From 9c9f209d9d81ea67cd84f53f470a592c252d845d Mon Sep 17 00:00:00 2001 From: Kemeng Shi Date: Mon, 5 Dec 2022 19:57:08 +0800 Subject: [PATCH] blk-throttle: remove repeat check of elapsed time There is no need to check elapsed time from last upgrade for each node in hierarchy. Move this check before traversing as throtl_can_upgrade do to remove repeat check. Reported-by: kernel test robot Acked-by: Tejun Heo Signed-off-by: Kemeng Shi Link: https://lore.kernel.org/r/20221205115709.251489-9-shikemeng@huaweicloud.com Signed-off-by: Jens Axboe --- block/blk-throttle.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index e6a087de414db..413e668249cfe 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1955,8 +1955,7 @@ static bool throtl_tg_can_downgrade(struct throtl_grp *tg) * If cgroup is below low limit, consider downgrade and throttle other * cgroups */ - if (time_after_eq(now, td->low_upgrade_time + td->throtl_slice) && - time_after_eq(now, tg_last_low_overflow_time(tg) + + if (time_after_eq(now, tg_last_low_overflow_time(tg) + td->throtl_slice) && (!throtl_tg_is_idle(tg) || !list_empty(&tg_to_blkg(tg)->blkcg->css.children))) @@ -1966,6 +1965,11 @@ static bool throtl_tg_can_downgrade(struct throtl_grp *tg) static bool throtl_hierarchy_can_downgrade(struct throtl_grp *tg) { + struct throtl_data *td = tg->td; + + if (time_before(jiffies, td->low_upgrade_time + td->throtl_slice)) + return false; + while (true) { if (!throtl_tg_can_downgrade(tg)) return false;