memcg: use find_lock_task_mm() in memory cgroups oom
authorKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Wed, 11 Aug 2010 01:03:00 +0000 (18:03 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 11 Aug 2010 15:59:19 +0000 (08:59 -0700)
commit158e0a2d1b3cffed8b46cbc56393a1394672ef79
treea044d53137609fdfc8c1afdde366b3e205c96eda
parent73045c47b6facbdf4656e6763c8cb469de4337e2
memcg: use find_lock_task_mm() in memory cgroups oom

When the OOM killer scans task, it check a task is under memcg or
not when it's called via memcg's context.

But, as Oleg pointed out, a thread group leader may have NULL ->mm
and task_in_mem_cgroup() may do wrong decision. We have to use
find_lock_task_mm() in memcg as generic OOM-Killer does.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/oom.h
mm/memcontrol.c
mm/oom_kill.c