diff options
| author | Johannes Weiner <hannes@cmpxchg.org> | 2014-12-10 15:43:54 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-10 17:41:07 -0800 |
| commit | 7bdd143c37e591c254d0991ac398a53f3f9ef1af (patch) | |
| tree | 0198540d14c53ee642729dcdf57f0faf94e8b2e2 /mm/memcontrol.c | |
| parent | b9982f8d27f893de2e8e98a25c68bb838b5311a4 (diff) | |
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/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 18 |
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); } /** |