diff options
| author | KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> | 2008-10-18 20:28:09 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-20 08:52:38 -0700 |
| commit | b7abea9630bc8ffc663a751e46680db25c4cdf8d (patch) | |
| tree | b37d5ba073ccea31328812c74598872d49a85735 /mm/migrate.c | |
| parent | 073e587ec2cc377867e53d8b8959738a8e16cff6 (diff) | |
| download | lwn-b7abea9630bc8ffc663a751e46680db25c4cdf8d.tar.gz lwn-b7abea9630bc8ffc663a751e46680db25c4cdf8d.zip | |
memcg: make page->mapping NULL before uncharge
This patch tries to make page->mapping to be NULL before
mem_cgroup_uncharge_cache_page() is called.
"page->mapping == NULL" is a good check for "whether the page is still
radix-tree or not". This patch also adds BUG_ON() to
mem_cgroup_uncharge_cache_page();
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/migrate.c')
| -rw-r--r-- | mm/migrate.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index 11c6c56ec017..6602941bfab0 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -330,8 +330,6 @@ static int migrate_page_move_mapping(struct address_space *mapping, __inc_zone_page_state(newpage, NR_FILE_PAGES); spin_unlock_irq(&mapping->tree_lock); - if (!PageSwapCache(newpage)) - mem_cgroup_uncharge_cache_page(page); return 0; } @@ -341,6 +339,8 @@ static int migrate_page_move_mapping(struct address_space *mapping, */ static void migrate_page_copy(struct page *newpage, struct page *page) { + int anon; + copy_highpage(newpage, page); if (PageError(page)) @@ -378,8 +378,13 @@ static void migrate_page_copy(struct page *newpage, struct page *page) #endif ClearPagePrivate(page); set_page_private(page, 0); + /* page->mapping contains a flag for PageAnon() */ + anon = PageAnon(page); page->mapping = NULL; + if (!anon) /* This page was removed from radix-tree. */ + mem_cgroup_uncharge_cache_page(page); + /* * If any waiters have accumulated on the new page then * wake them up. |