memory cgroup enhancements: force_empty interface for dropping all account in empty...
authorKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Thu, 7 Feb 2008 08:14:16 +0000 (00:14 -0800)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Thu, 7 Feb 2008 16:42:20 +0000 (08:42 -0800)
commitcc8475822f8a4b17e9b76e7fadb6b9a341860422
treeb7e3ee9aba56ffaf93130786f3439cc43339e586
parent417eead30434b4bd09a54455e839cf9a62c05460
memory cgroup enhancements: force_empty interface for dropping all account in empty cgroup

This patch adds an interface "memory.force_empty".  Any write to this file
will drop all charges in this cgroup if there is no task under.

%echo 1 > /....../memory.force_empty

will drop all charges of memory cgroup if cgroup's tasks is empty.

This is useful to invoke rmdir() against memory cgroup successfully.

Tested and worked well on x86_64/fake-NUMA system.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Paul Menage <menage@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: David Rientjes <rientjes@google.com>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/memcontrol.c