Currently mem_cgroup_read_stat2() imprecise result for performance reasons. However, for statistics like 'memory.stat' we'd want the precise results.
Make mem_cgroup_read_stat2() slower but preciser, and add unprecise but fast mem_cgroup_read_stat2_fast() for performance-sensitive caller - dcache_is_low(). https://jira.sw.ru/browse/PSBM-69332 Signed-off-by: Andrey Ryabinin <aryabi...@virtuozzo.com> --- mm/memcontrol.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 19af6a9d9fc8..5ab5e82c924e 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -973,12 +973,19 @@ mem_cgroup_read_stat(struct mem_cgroup *memcg, enum mem_cgroup_stat_index idx) val = 0; return val; } + static inline unsigned long -mem_cgroup_read_stat2(struct mem_cgroup *memcg, enum mem_cgroup_stat2_index idx) +mem_cgroup_read_stat2_fast(struct mem_cgroup *memcg, enum mem_cgroup_stat2_index idx) { return percpu_counter_read_positive(&memcg->stat2.counters[idx]); } +static inline unsigned long +mem_cgroup_read_stat2(struct mem_cgroup *memcg, enum mem_cgroup_stat2_index idx) +{ + return percpu_counter_sum_positive(&memcg->stat2.counters[idx]); +} + static void mem_cgroup_update_swap_max(struct mem_cgroup *memcg) { long long swap; @@ -1611,9 +1618,9 @@ bool mem_cgroup_dcache_is_low(struct mem_cgroup *memcg, int vfs_cache_min_ratio) { unsigned long anon, file, dcache; - anon = mem_cgroup_read_stat2(memcg, MEM_CGROUP_STAT_RSS); - file = mem_cgroup_read_stat2(memcg, MEM_CGROUP_STAT_CACHE); - dcache = mem_cgroup_read_stat2(memcg, MEM_CGROUP_STAT_SLAB_RECLAIMABLE); + anon = mem_cgroup_read_stat2_fast(memcg, MEM_CGROUP_STAT_RSS); + file = mem_cgroup_read_stat2_fast(memcg, MEM_CGROUP_STAT_CACHE); + dcache = mem_cgroup_read_stat2_fast(memcg, MEM_CGROUP_STAT_SLAB_RECLAIMABLE); return dcache / vfs_cache_min_ratio < (anon + file + dcache) / 100; -- 2.13.0 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
