| Message ID | 20230328061638.203420-10-yosryahmed@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | memcg: make rstat flushing irq and sleep friendly | expand |
On Mon, Mar 27, 2023 at 11:17 PM Yosry Ahmed <yosryahmed@google.com> wrote: > > In some situations, we may end up calling memcg_rstat_updated() with a > value of 0, which means the stat was not actually updated. An example is > if we fail to reclaim any pages in shrink_folio_list(). > > Do not add the cgroup to the rstat updated tree in this case, to avoid > unnecessarily flushing it. > > Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Shakeel Butt <shakeelb@google.com>
On Tue, Mar 28, 2023 at 06:16:38AM +0000, Yosry Ahmed wrote: > In some situations, we may end up calling memcg_rstat_updated() with a > value of 0, which means the stat was not actually updated. An example is > if we fail to reclaim any pages in shrink_folio_list(). > > Do not add the cgroup to the rstat updated tree in this case, to avoid > unnecessarily flushing it. > > Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 0c0e74188e90..828e670e721a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -618,6 +618,9 @@ static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) { unsigned int x; + if (!val) + return; + cgroup_rstat_updated(memcg->css.cgroup, smp_processor_id()); x = __this_cpu_add_return(stats_updates, abs(val));
In some situations, we may end up calling memcg_rstat_updated() with a value of 0, which means the stat was not actually updated. An example is if we fail to reclaim any pages in shrink_folio_list(). Do not add the cgroup to the rstat updated tree in this case, to avoid unnecessarily flushing it. Signed-off-by: Yosry Ahmed <yosryahmed@google.com> --- mm/memcontrol.c | 3 +++ 1 file changed, 3 insertions(+)