From: Johannes Weiner Date: Wed, 10 Dec 2014 23:44:00 +0000 (-0800) Subject: mm: memcontrol: remove unnecessary PCG_MEM memory charge flag X-Git-Url: http://git.efficios.com/?p=deliverable%2Flinux.git;a=commitdiff_plain;h=f4aaa8b43d90294ca7546317997c452600e9a8a7 mm: memcontrol: remove unnecessary PCG_MEM memory charge flag PCG_MEM is a remnant from an earlier version of 0a31bc97c80c ("mm: memcontrol: rewrite uncharge API"), used to tell whether migration cleared a charge while leaving pc->mem_cgroup valid and PCG_USED set. But in the final version, mem_cgroup_migrate() directly uncharges the source page, rendering this distinction unnecessary. Remove it. Signed-off-by: Johannes Weiner Cc: Hugh Dickins Acked-by: Michal Hocko Reviewed-by: Vladimir Davydov Acked-by: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/linux/page_cgroup.h b/include/linux/page_cgroup.h index da62ee2be28b..97536e685843 100644 --- a/include/linux/page_cgroup.h +++ b/include/linux/page_cgroup.h @@ -4,7 +4,6 @@ enum { /* flags for mem_cgroup */ PCG_USED = 0x01, /* This page is charged to a memcg */ - PCG_MEM = 0x02, /* This page holds a memory charge */ }; struct pglist_data; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index baf3b535b180..3dfb56a93117 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2614,7 +2614,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg, * have the page locked */ pc->mem_cgroup = memcg; - pc->flags = PCG_USED | PCG_MEM; + pc->flags = PCG_USED; if (lrucare) unlock_page_lru(page, isolated); @@ -6156,8 +6156,6 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage, if (!PageCgroupUsed(pc)) return; - VM_BUG_ON_PAGE(!(pc->flags & PCG_MEM), oldpage); - if (lrucare) lock_page_lru(oldpage, &isolated);