From 9a4caf1e9fa4864ce21ba9584a2c336bfbc72740 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Wed, 3 May 2017 14:52:45 -0700 Subject: [PATCH] mm: memcontrol: provide shmem statistics Cgroups currently don't report how much shmem they use, which can be useful data to have, in particular since shmem is included in the cache/file item while being reclaimed like anonymous memory. Add a counter to track shmem pages during charging and uncharging. Link: http://lkml.kernel.org/r/20170221164343.32252-1-hannes@cmpxchg.org Signed-off-by: Johannes Weiner Reported-by: Chris Down Cc: Michal Hocko Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/cgroup-v2.txt | 5 +++++ include/linux/memcontrol.h | 1 + mm/memcontrol.c | 28 ++++++++++++++++++++-------- 3 files changed, 26 insertions(+), 8 deletions(-) diff --git a/Documentation/cgroup-v2.txt b/Documentation/cgroup-v2.txt index 49d7c997fa1e..e50b95c25868 100644 --- a/Documentation/cgroup-v2.txt +++ b/Documentation/cgroup-v2.txt @@ -871,6 +871,11 @@ PAGE_SIZE multiple when read back. Amount of memory used in network transmission buffers + shmem + + Amount of cached filesystem data that is swap-backed, + such as tmpfs, shm segments, shared anonymous mmap()s + file_mapped Amount of cached filesystem data mapped with mmap() diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index bb7250c45cb8..c5ebb32fef49 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -46,6 +46,7 @@ enum mem_cgroup_stat_index { MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */ MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */ MEM_CGROUP_STAT_RSS_HUGE, /* # of pages charged as anon huge */ + MEM_CGROUP_STAT_SHMEM, /* # of pages charged as shmem */ MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */ MEM_CGROUP_STAT_DIRTY, /* # of dirty pages in page cache */ MEM_CGROUP_STAT_WRITEBACK, /* # of pages under writeback */ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2bd7541d7c11..490d5b4676c1 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -104,6 +104,7 @@ static const char * const mem_cgroup_stat_names[] = { "cache", "rss", "rss_huge", + "shmem", "mapped_file", "dirty", "writeback", @@ -608,9 +609,13 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg, if (PageAnon(page)) __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_RSS], nr_pages); - else + else { __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_pages); + if (PageSwapBacked(page)) + __this_cpu_add(memcg->stat->count[MEM_CGROUP_STAT_SHMEM], + nr_pages); + } if (compound) { VM_BUG_ON_PAGE(!PageTransHuge(page), page); @@ -5208,6 +5213,8 @@ static int memory_stat_show(struct seq_file *m, void *v) seq_printf(m, "sock %llu\n", (u64)stat[MEMCG_SOCK] * PAGE_SIZE); + seq_printf(m, "shmem %llu\n", + (u64)stat[MEM_CGROUP_STAT_SHMEM] * PAGE_SIZE); seq_printf(m, "file_mapped %llu\n", (u64)stat[MEM_CGROUP_STAT_FILE_MAPPED] * PAGE_SIZE); seq_printf(m, "file_dirty %llu\n", @@ -5476,8 +5483,8 @@ void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg, static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, unsigned long nr_anon, unsigned long nr_file, - unsigned long nr_huge, unsigned long nr_kmem, - struct page *dummy_page) + unsigned long nr_kmem, unsigned long nr_huge, + unsigned long nr_shmem, struct page *dummy_page) { unsigned long nr_pages = nr_anon + nr_file + nr_kmem; unsigned long flags; @@ -5495,6 +5502,7 @@ static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS], nr_anon); __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file); __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge); + __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_SHMEM], nr_shmem); __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout); __this_cpu_add(memcg->stat->nr_page_events, nr_pages); memcg_check_events(memcg, dummy_page); @@ -5507,6 +5515,7 @@ static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, static void uncharge_list(struct list_head *page_list) { struct mem_cgroup *memcg = NULL; + unsigned long nr_shmem = 0; unsigned long nr_anon = 0; unsigned long nr_file = 0; unsigned long nr_huge = 0; @@ -5539,9 +5548,9 @@ static void uncharge_list(struct list_head *page_list) if (memcg != page->mem_cgroup) { if (memcg) { uncharge_batch(memcg, pgpgout, nr_anon, nr_file, - nr_huge, nr_kmem, page); - pgpgout = nr_anon = nr_file = - nr_huge = nr_kmem = 0; + nr_kmem, nr_huge, nr_shmem, page); + pgpgout = nr_anon = nr_file = nr_kmem = 0; + nr_huge = nr_shmem = 0; } memcg = page->mem_cgroup; } @@ -5555,8 +5564,11 @@ static void uncharge_list(struct list_head *page_list) } if (PageAnon(page)) nr_anon += nr_pages; - else + else { nr_file += nr_pages; + if (PageSwapBacked(page)) + nr_shmem += nr_pages; + } pgpgout++; } else { nr_kmem += 1 << compound_order(page); @@ -5568,7 +5580,7 @@ static void uncharge_list(struct list_head *page_list) if (memcg) uncharge_batch(memcg, pgpgout, nr_anon, nr_file, - nr_huge, nr_kmem, page); + nr_kmem, nr_huge, nr_shmem, page); } /** -- 2.20.1