memcg: add file-based RSS accounting
Add file RSS tracking per memory cgroup
We currently don't track file RSS, the RSS we report is actually anon RSS.
All the file mapped pages, come in through the page cache and get
accounted there. This patch adds support for accounting file RSS pages.
It should
1. Help improve the metrics reported by the memory resource controller
2. Will form the basis for a future shared memory accounting heuristic
that has been proposed by Kamezawa.
Unfortunately, we cannot rename the existing "rss" keyword used in
memory.stat to "anon_rss". We however, add "mapped_file" data and hope to
educate the end user through documentation.
[hugh.dickins@tiscali.co.uk: fix mem_cgroup_update_mapped_file_stat oops]
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.cn>
Cc: Paul Menage <menage@google.com>
Cc: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 45add35..e46a073 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -117,7 +117,7 @@
}
extern bool mem_cgroup_oom_called(struct task_struct *task);
-
+void mem_cgroup_update_mapped_file_stat(struct page *page, int val);
#else /* CONFIG_CGROUP_MEM_RES_CTLR */
struct mem_cgroup;
@@ -271,6 +271,11 @@
{
}
+static inline void mem_cgroup_update_mapped_file_stat(struct page *page,
+ int val)
+{
+}
+
#endif /* CONFIG_CGROUP_MEM_CONT */
#endif /* _LINUX_MEMCONTROL_H */
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 70db6e0..6f68290 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -62,7 +62,8 @@
* For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
*/
MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */
- MEM_CGROUP_STAT_RSS, /* # of pages charged as rss */
+ MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */
+ MEM_CGROUP_STAT_MAPPED_FILE, /* # of pages charged as file rss */
MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */
MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */
@@ -900,6 +901,44 @@
mem_cgroup_walk_tree(mem, NULL, record_last_oom_cb);
}
+/*
+ * Currently used to update mapped file statistics, but the routine can be
+ * generalized to update other statistics as well.
+ */
+void mem_cgroup_update_mapped_file_stat(struct page *page, int val)
+{
+ struct mem_cgroup *mem;
+ struct mem_cgroup_stat *stat;
+ struct mem_cgroup_stat_cpu *cpustat;
+ int cpu;
+ struct page_cgroup *pc;
+
+ if (!page_is_file_cache(page))
+ return;
+
+ pc = lookup_page_cgroup(page);
+ if (unlikely(!pc))
+ return;
+
+ lock_page_cgroup(pc);
+ mem = pc->mem_cgroup;
+ if (!mem)
+ goto done;
+
+ if (!PageCgroupUsed(pc))
+ goto done;
+
+ /*
+ * Preemption is already disabled, we don't need get_cpu()
+ */
+ cpu = smp_processor_id();
+ stat = &mem->stat;
+ cpustat = &stat->cpustat[cpu];
+
+ __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE, val);
+done:
+ unlock_page_cgroup(pc);
+}
/*
* Unlike exported interface, "oom" parameter is added. if oom==true,
@@ -1098,6 +1137,10 @@
struct mem_cgroup_per_zone *from_mz, *to_mz;
int nid, zid;
int ret = -EBUSY;
+ struct page *page;
+ int cpu;
+ struct mem_cgroup_stat *stat;
+ struct mem_cgroup_stat_cpu *cpustat;
VM_BUG_ON(from == to);
VM_BUG_ON(PageLRU(pc->page));
@@ -1118,6 +1161,23 @@
res_counter_uncharge(&from->res, PAGE_SIZE);
mem_cgroup_charge_statistics(from, pc, false);
+
+ page = pc->page;
+ if (page_is_file_cache(page) && page_mapped(page)) {
+ cpu = smp_processor_id();
+ /* Update mapped_file data for mem_cgroup "from" */
+ stat = &from->stat;
+ cpustat = &stat->cpustat[cpu];
+ __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE,
+ -1);
+
+ /* Update mapped_file data for mem_cgroup "to" */
+ stat = &to->stat;
+ cpustat = &stat->cpustat[cpu];
+ __mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_MAPPED_FILE,
+ 1);
+ }
+
if (do_swap_account)
res_counter_uncharge(&from->memsw, PAGE_SIZE);
css_put(&from->css);
@@ -2046,6 +2106,7 @@
enum {
MCS_CACHE,
MCS_RSS,
+ MCS_MAPPED_FILE,
MCS_PGPGIN,
MCS_PGPGOUT,
MCS_INACTIVE_ANON,
@@ -2066,6 +2127,7 @@
} memcg_stat_strings[NR_MCS_STAT] = {
{"cache", "total_cache"},
{"rss", "total_rss"},
+ {"mapped_file", "total_mapped_file"},
{"pgpgin", "total_pgpgin"},
{"pgpgout", "total_pgpgout"},
{"inactive_anon", "total_inactive_anon"},
@@ -2086,6 +2148,8 @@
s->stat[MCS_CACHE] += val * PAGE_SIZE;
val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS);
s->stat[MCS_RSS] += val * PAGE_SIZE;
+ val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_MAPPED_FILE);
+ s->stat[MCS_MAPPED_FILE] += val * PAGE_SIZE;
val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_PGPGIN_COUNT);
s->stat[MCS_PGPGIN] += val;
val = mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_PGPGOUT_COUNT);
diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c
index 4f31c9b..672089d 100644
--- a/mm/page_cgroup.c
+++ b/mm/page_cgroup.c
@@ -99,6 +99,8 @@
unsigned long pfn = page_to_pfn(page);
struct mem_section *section = __pfn_to_section(pfn);
+ if (!section->page_cgroup)
+ return NULL;
return section->page_cgroup + pfn;
}
diff --git a/mm/rmap.c b/mm/rmap.c
index c9ccc1a..836c6c6 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -703,8 +703,10 @@
*/
void page_add_file_rmap(struct page *page)
{
- if (atomic_inc_and_test(&page->_mapcount))
+ if (atomic_inc_and_test(&page->_mapcount)) {
__inc_zone_page_state(page, NR_FILE_MAPPED);
+ mem_cgroup_update_mapped_file_stat(page, 1);
+ }
}
#ifdef CONFIG_DEBUG_VM
@@ -753,6 +755,7 @@
mem_cgroup_uncharge_page(page);
__dec_zone_page_state(page,
PageAnon(page) ? NR_ANON_PAGES : NR_FILE_MAPPED);
+ mem_cgroup_update_mapped_file_stat(page, -1);
/*
* It would be tidy to reset the PageAnon mapping here,
* but that might overwrite a racing page_add_anon_rmap