diff options
Diffstat (limited to 'mm')
-rw-r--r-- | mm/memcontrol.c | 45 | ||||
-rw-r--r-- | mm/vmscan.c | 2 | ||||
-rw-r--r-- | mm/workingset.c | 2 |
3 files changed, 38 insertions, 11 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index a9f18456a16b..06786dea50b8 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -635,7 +635,7 @@ static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) } } -static void __mem_cgroup_flush_stats(void) +static void do_flush_stats(bool atomic) { /* * We always flush the entire tree, so concurrent flushers can just @@ -647,26 +647,46 @@ static void __mem_cgroup_flush_stats(void) return; WRITE_ONCE(flush_next_time, jiffies_64 + 2*FLUSH_TIME); - cgroup_rstat_flush_atomic(root_mem_cgroup->css.cgroup); + + if (atomic) + cgroup_rstat_flush_atomic(root_mem_cgroup->css.cgroup); + else + cgroup_rstat_flush(root_mem_cgroup->css.cgroup); + atomic_set(&stats_flush_threshold, 0); atomic_set(&stats_flush_ongoing, 0); } +static bool should_flush_stats(void) +{ + return atomic_read(&stats_flush_threshold) > num_online_cpus(); +} + void mem_cgroup_flush_stats(void) { - if (atomic_read(&stats_flush_threshold) > num_online_cpus()) - __mem_cgroup_flush_stats(); + if (should_flush_stats()) + do_flush_stats(false); } -void mem_cgroup_flush_stats_ratelimited(void) +void mem_cgroup_flush_stats_atomic(void) +{ + if (should_flush_stats()) + do_flush_stats(true); +} + +void mem_cgroup_flush_stats_atomic_ratelimited(void) { if (time_after64(jiffies_64, READ_ONCE(flush_next_time))) - mem_cgroup_flush_stats(); + mem_cgroup_flush_stats_atomic(); } static void flush_memcg_stats_dwork(struct work_struct *w) { - __mem_cgroup_flush_stats(); + /* + * Always flush here so that flushing in latency-sensitive paths is + * as cheap as possible. + */ + do_flush_stats(false); queue_delayed_work(system_unbound_wq, &stats_flush_dwork, FLUSH_TIME); } @@ -3686,9 +3706,12 @@ static unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) * done from irq context; use stale stats in this case. * Arguably, usage threshold events are not reliable on the root * memcg anyway since its usage is ill-defined. + * + * Additionally, other call paths through memcg_check_events() + * disable irqs, so make sure we are flushing stats atomically. */ if (in_task()) - mem_cgroup_flush_stats(); + mem_cgroup_flush_stats_atomic(); val = memcg_page_state(memcg, NR_FILE_PAGES) + memcg_page_state(memcg, NR_ANON_MAPPED); if (swap) @@ -4611,7 +4634,11 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); struct mem_cgroup *parent; - mem_cgroup_flush_stats(); + /* + * wb_writeback() takes a spinlock and calls + * wb_over_bg_thresh()->mem_cgroup_wb_stats(). Do not sleep. + */ + mem_cgroup_flush_stats_atomic(); *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY); *pwriteback = memcg_page_state(memcg, NR_WRITEBACK); diff --git a/mm/vmscan.c b/mm/vmscan.c index 98719e72b5e2..c68db50ec109 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2861,7 +2861,7 @@ 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(); + mem_cgroup_flush_stats_atomic(); /* * Determine the scan balance between anon and file LRUs. diff --git a/mm/workingset.c b/mm/workingset.c index af862c6738c3..dab0c362b9e3 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -462,7 +462,7 @@ void workingset_refault(struct folio *folio, void *shadow) mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr); - mem_cgroup_flush_stats_ratelimited(); + mem_cgroup_flush_stats_atomic_ratelimited(); /* * Compare the distance to the existing workingset size. We * don't activate pages that couldn't stay resident even if |