[lkml]   [2011]   [Jan]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [BUGFIX][PATCH 2/4] memcg: fix charge path for THP and allow early retirement
On Fri, Jan 28, 2011 at 12:26:08PM +0900, KAMEZAWA Hiroyuki wrote:
> From: KAMEZAWA Hiroyuki <>
> When THP is used, Hugepage size charge can happen. It's not handled
> correctly in mem_cgroup_do_charge(). For example, THP can fallback
> to small page allocation when HUGEPAGE allocation seems difficult
> or busy, but memory cgroup doesn't understand it and continue to
> try HUGEPAGE charging. And the worst thing is memory cgroup
> believes 'memory reclaim succeeded' if limit - usage > PAGE_SIZE.
> By this, khugepaged etc...can goes into inifinite reclaim loop
> if tasks in memcg are busy.
> After this patch
> - Hugepage allocation will fail if 1st trial of page reclaim fails.
> Changelog:
> - make changes small. removed renaming codes.
> Signed-off-by: KAMEZAWA Hiroyuki <>
> ---
> mm/memcontrol.c | 28 ++++++++++++++++++++++++----
> 1 file changed, 24 insertions(+), 4 deletions(-)

Was there something wrong with my oneline fix?

Really, there is no way to make this a beautiful fix. The way this
function is split up makes no sense, and the constant addition of more
and more flags just to correctly communicate with _one callsite_
should be an obvious hint.

 \ /
  Last update: 2011-01-28 08:59    [W:0.109 / U:15.368 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site