memcg: never OOM when charging huge pages

Huge page coverage should obviously have less priority than the continued
execution of a process.

Never kill a process when charging it a huge page fails.  Instead, give up
after the first failed reclaim attempt and fall back to regular pages.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: 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>
This commit is contained in:
Johannes Weiner 2011-02-01 15:52:44 -08:00 committed by Linus Torvalds
parent 19942822df
commit 8493ae439f
1 changed files with 9 additions and 3 deletions

View File

@ -2351,13 +2351,19 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask, enum charge_type ctype)
{
struct mem_cgroup *mem = NULL;
struct page_cgroup *pc;
int ret;
int page_size = PAGE_SIZE;
struct page_cgroup *pc;
bool oom = true;
int ret;
if (PageTransHuge(page)) {
page_size <<= compound_order(page);
VM_BUG_ON(!PageTransHuge(page));
/*
* Never OOM-kill a process for a huge page. The
* fault handler will fall back to regular pages.
*/
oom = false;
}
pc = lookup_page_cgroup(page);
@ -2366,7 +2372,7 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
return 0;
prefetchw(pc);
ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, true, page_size);
ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, oom, page_size);
if (ret || !mem)
return ret;