From: Hugh Dickins <hughd@google.com>
Date: Fri, 25 Feb 2011 22:44:29 +0000 (-0800)
Subject: memcg: more mem_cgroup_uncharge() batching
X-Git-Url: https://git.karo-electronics.de/?p=mv-sheeva.git;a=commitdiff_plain;h=e5598f8bf5449bc09e4005600ead32e6f2a3e79b

memcg: more mem_cgroup_uncharge() batching

It seems odd that truncate_inode_pages_range(), called not only when
truncating but also when evicting inodes, has mem_cgroup_uncharge_start
and _end() batching in its second loop to clear up a few leftovers, but
not in its first loop that does almost all the work: add them there too.

Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/truncate.c b/mm/truncate.c
index 49feb46e77b..d64296be00d 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -225,6 +225,7 @@ void truncate_inode_pages_range(struct address_space *mapping,
 	next = start;
 	while (next <= end &&
 	       pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
+		mem_cgroup_uncharge_start();
 		for (i = 0; i < pagevec_count(&pvec); i++) {
 			struct page *page = pvec.pages[i];
 			pgoff_t page_index = page->index;
@@ -247,6 +248,7 @@ void truncate_inode_pages_range(struct address_space *mapping,
 			unlock_page(page);
 		}
 		pagevec_release(&pvec);
+		mem_cgroup_uncharge_end();
 		cond_resched();
 	}