Messages in this thread Patch in this message | | | Date | Sun, 14 May 2023 09:33:38 -0700 | Subject | [PATCH 1/1] sched/psi: avoid resetting the min update period when it is unnecessary | From | Suren Baghdasaryan <> |
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From: Yang Yang <yang.yang29@zte.com.cn>
Psi_group's poll_min_period is determined by the minimum window size of psi_trigger when creating new triggers. While destroying a psi_trigger, there is no need to reset poll_min_period if the psi_trigger being destroyed did not have the minimum window size, since in this condition poll_min_period will remain the same as before.
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn> Acked-by: Suren Baghdasaryan <surenb@google.com> --- rebase of https://lore.kernel.org/all/202305121642367753446@zte.com.cn/ over git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched/core branch
kernel/sched/psi.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index b49af594ad28..81fca77397f6 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -1407,11 +1407,16 @@ void psi_trigger_destroy(struct psi_trigger *t) group->rtpoll_nr_triggers[t->state]--; if (!group->rtpoll_nr_triggers[t->state]) group->rtpoll_states &= ~(1 << t->state); - /* reset min update period for the remaining triggers */ - list_for_each_entry(tmp, &group->rtpoll_triggers, node) - period = min(period, div_u64(tmp->win.size, - UPDATES_PER_WINDOW)); - group->rtpoll_min_period = period; + /* + * Reset min update period for the remaining triggers + * iff the destroying trigger had the min window size. + */ + if (group->rtpoll_min_period == div_u64(t->win.size, UPDATES_PER_WINDOW)) { + list_for_each_entry(tmp, &group->rtpoll_triggers, node) + period = min(period, div_u64(tmp->win.size, + UPDATES_PER_WINDOW)); + group->rtpoll_min_period = period; + } /* Destroy rtpoll_task when the last trigger is destroyed */ if (group->rtpoll_states == 0) { group->rtpoll_until = 0; -- 2.40.1.606.ga4b1b128d6-goog
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