diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 006fe142d4b..f9ae4b4c36e 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -63,8 +63,15 @@ static int really_do_swap_account __initdata = 1; /* for remember boot option*/ #define do_swap_account (0) #endif -#define SOFTLIMIT_EVENTS_THRESH (1000) -#define THRESHOLDS_EVENTS_THRESH (100) +/* + * Per memcg event counter is incremented at every pagein/pageout. This counter + * is used for trigger some periodic events. This is straightforward and better + * than using jiffies etc. to handle periodic memcg event. + * + * These values will be used as !((event) & ((1 <<(thresh)) - 1)) + */ +#define THRESHOLDS_EVENTS_THRESH (7) /* once in 128 */ +#define SOFTLIMIT_EVENTS_THRESH (10) /* once in 1024 */ /* * Statistics for memory cgroup. @@ -79,10 +86,7 @@ enum mem_cgroup_stat_index { MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */ MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */ MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */ - MEM_CGROUP_STAT_SOFTLIMIT, /* decrements on each page in/out. - used by soft limit implementation */ - MEM_CGROUP_STAT_THRESHOLDS, /* decrements on each page in/out. - used by threshold implementation */ + MEM_CGROUP_EVENTS, /* incremented at every pagein/pageout */ MEM_CGROUP_STAT_NSTATS, }; @@ -154,7 +158,6 @@ struct mem_cgroup_threshold_ary { struct mem_cgroup_threshold entries[0]; }; -static bool mem_cgroup_threshold_check(struct mem_cgroup *mem); static void mem_cgroup_threshold(struct mem_cgroup *mem); /* @@ -392,19 +395,6 @@ mem_cgroup_remove_exceeded(struct mem_cgroup *mem, spin_unlock(&mctz->lock); } -static bool mem_cgroup_soft_limit_check(struct mem_cgroup *mem) -{ - bool ret = false; - s64 val; - - val = this_cpu_read(mem->stat->count[MEM_CGROUP_STAT_SOFTLIMIT]); - if (unlikely(val < 0)) { - this_cpu_write(mem->stat->count[MEM_CGROUP_STAT_SOFTLIMIT], - SOFTLIMIT_EVENTS_THRESH); - ret = true; - } - return ret; -} static void mem_cgroup_update_tree(struct mem_cgroup *mem, struct page *page) { @@ -542,8 +532,7 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, __this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_PGPGIN_COUNT]); else __this_cpu_inc(mem->stat->count[MEM_CGROUP_STAT_PGPGOUT_COUNT]); - __this_cpu_dec(mem->stat->count[MEM_CGROUP_STAT_SOFTLIMIT]); - __this_cpu_dec(mem->stat->count[MEM_CGROUP_STAT_THRESHOLDS]); + __this_cpu_inc(mem->stat->count[MEM_CGROUP_EVENTS]); preempt_enable(); } @@ -563,6 +552,29 @@ static unsigned long mem_cgroup_get_local_zonestat(struct mem_cgroup *mem, return total; } +static bool __memcg_event_check(struct mem_cgroup *mem, int event_mask_shift) +{ + s64 val; + + val = this_cpu_read(mem->stat->count[MEM_CGROUP_EVENTS]); + + return !(val & ((1 << event_mask_shift) - 1)); +} + +/* + * Check events in order. + * + */ +static void memcg_check_events(struct mem_cgroup *mem, struct page *page) +{ + /* threshold event is triggered in finer grain than soft limit */ + if (unlikely(__memcg_event_check(mem, THRESHOLDS_EVENTS_THRESH))) { + mem_cgroup_threshold(mem); + if (unlikely(__memcg_event_check(mem, SOFTLIMIT_EVENTS_THRESH))) + mem_cgroup_update_tree(mem, page); + } +} + static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) { return container_of(cgroup_subsys_state(cont, @@ -1686,11 +1698,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *mem, * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree. * if they exceeds softlimit. */ - if (mem_cgroup_soft_limit_check(mem)) - mem_cgroup_update_tree(mem, pc->page); - if (mem_cgroup_threshold_check(mem)) - mem_cgroup_threshold(mem); - + memcg_check_events(mem, pc->page); } /** @@ -1760,6 +1768,11 @@ static int mem_cgroup_move_account(struct page_cgroup *pc, ret = 0; } unlock_page_cgroup(pc); + /* + * check events + */ + memcg_check_events(to, pc->page); + memcg_check_events(from, pc->page); return ret; } @@ -2128,10 +2141,7 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) mz = page_cgroup_zoneinfo(pc); unlock_page_cgroup(pc); - if (mem_cgroup_soft_limit_check(mem)) - mem_cgroup_update_tree(mem, page); - if (mem_cgroup_threshold_check(mem)) - mem_cgroup_threshold(mem); + memcg_check_events(mem, page); /* at swapout, this memcg will be accessed to record to swap */ if (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT) css_put(&mem->css); @@ -3215,20 +3225,6 @@ static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, return 0; } -static bool mem_cgroup_threshold_check(struct mem_cgroup *mem) -{ - bool ret = false; - s64 val; - - val = this_cpu_read(mem->stat->count[MEM_CGROUP_STAT_THRESHOLDS]); - if (unlikely(val < 0)) { - this_cpu_write(mem->stat->count[MEM_CGROUP_STAT_THRESHOLDS], - THRESHOLDS_EVENTS_THRESH); - ret = true; - } - return ret; -} - static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) { struct mem_cgroup_threshold_ary *t;