summaryrefslogtreecommitdiffstats
path: root/mm
diff options
context:
space:
mode:
authorJohannes Weiner <hannes@cmpxchg.org>2014-12-11 00:43:54 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-11 02:41:07 +0100
commit7bdd143c37e591c254d0991ac398a53f3f9ef1af (patch)
tree0198540d14c53ee642729dcdf57f0faf94e8b2e2 /mm
parentmm: memcontrol: micro-optimize mem_cgroup_split_huge_fixup() (diff)
downloadlinux-7bdd143c37e591c254d0991ac398a53f3f9ef1af.tar.xz
linux-7bdd143c37e591c254d0991ac398a53f3f9ef1af.zip
mm: memcontrol: uncharge pages on swapout
This series gets rid of the remaining page_cgroup flags, thus cutting the memcg per-page overhead down to one pointer. This patch (of 4): mem_cgroup_swapout() is called with exclusive access to the page at the end of the page's lifetime. Instead of clearing the PCG_MEMSW flag and deferring the uncharge, just do it right away. This allows follow-up patches to simplify the uncharge code. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Hugh Dickins <hughd@google.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Vladimir Davydov <vdavydov@parallels.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/memcontrol.c18
1 files changed, 14 insertions, 4 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 8c10d4ca9c3f..266a440c89f9 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5777,6 +5777,7 @@ static void __init enable_swap_cgroup(void)
*/
void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
{
+ struct mem_cgroup *memcg;
struct page_cgroup *pc;
unsigned short oldid;
@@ -5793,13 +5794,22 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
return;
VM_BUG_ON_PAGE(!(pc->flags & PCG_MEMSW), page);
+ memcg = pc->mem_cgroup;
- oldid = swap_cgroup_record(entry, mem_cgroup_id(pc->mem_cgroup));
+ oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg));
VM_BUG_ON_PAGE(oldid, page);
+ mem_cgroup_swap_statistics(memcg, true);
+
+ pc->flags = 0;
- pc->flags &= ~PCG_MEMSW;
- css_get(&pc->mem_cgroup->css);
- mem_cgroup_swap_statistics(pc->mem_cgroup, true);
+ if (!mem_cgroup_is_root(memcg))
+ page_counter_uncharge(&memcg->memory, 1);
+
+ /* XXX: caller holds IRQ-safe mapping->tree_lock */
+ VM_BUG_ON(!irqs_disabled());
+
+ mem_cgroup_charge_statistics(memcg, page, -1);
+ memcg_check_events(memcg, page);
}
/**