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charset=us-ascii Content-Disposition: inline In-Reply-To: <20230328221644.803272-9-yosryahmed@google.com> X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: iaxs5b7qru5gwbpb59ad4g5jbwrc8j1o X-Rspamd-Queue-Id: F35FD1C0010 X-HE-Tag: 1680162057-165720 X-HE-Meta: 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 n0F2eGQf KlxMNUHBjPbHNbw2q2EexuaWaOWXTh5r1HA8/R4+//WUfBXCIamxT9nxGUEqNPQbDkdex/PT7ZmvGZr/PxqM8aOs7Ox5FDcq7arMHT4ZKpk6PXTteoov2QgziGemZ1qTROL7+g+v/AIEIUgoxgfn/3FrcAfjmM/P72YTKDczMdOtZDi0rsqPg5ZC+Ysz6SuwiPKZj9s8GkJX/U+rg9u9zPp644FSetXA7/7GnBhqid3L4rlUDQXOLGzkaJA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue 28-03-23 22:16:43, Yosry Ahmed wrote: > Memory reclaim is a sleepable context. Allow sleeping when flushing > memcg stats to avoid unnecessarily performing a lot of work without > sleeping. This can slow down reclaim code if flushing stats is taking > too long, but there is already multiple cond_resched()'s in reclaim > code. Why is this preferred? Memory reclaim is surely a slow path but what is the advantage of calling mem_cgroup_flush_stats here? > Signed-off-by: Yosry Ahmed > Acked-by: Shakeel Butt > Acked-by: Johannes Weiner > --- > mm/vmscan.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index a9511ccb936f..9c1c5e8b24b8 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -2845,7 +2845,7 @@ static void prepare_scan_count(pg_data_t *pgdat, struct scan_control *sc) > * Flush the memory cgroup stats, so that we read accurate per-memcg > * lruvec stats for heuristics. > */ > - mem_cgroup_flush_stats_atomic(); > + mem_cgroup_flush_stats(); > > /* > * Determine the scan balance between anon and file LRUs. > -- > 2.40.0.348.gf938b09366-goog -- Michal Hocko SUSE Labs