diff options
author | Balbir Singh <balbir@linux.vnet.ibm.com> | 2008-04-29 08:00:16 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-04-29 15:06:10 (GMT) |
commit | cf475ad28ac35cc9ba612d67158f29b73b38b05d (patch) | |
tree | 2c7cd568d00357bd42643ea602884e731cc24f26 /kernel/cgroup.c | |
parent | 29486df325e1fe6e1764afcb19e3370804c2b002 (diff) | |
download | linux-fsl-qoriq-cf475ad28ac35cc9ba612d67158f29b73b38b05d.tar.xz |
cgroups: add an owner to the mm_struct
Remove the mem_cgroup member from mm_struct and instead adds an owner.
This approach was suggested by Paul Menage. The advantage of this approach
is that, once the mm->owner is known, using the subsystem id, the cgroup
can be determined. It also allows several control groups that are
virtually grouped by mm_struct, to exist independent of the memory
controller i.e., without adding mem_cgroup's for each controller, to
mm_struct.
A new config option CONFIG_MM_OWNER is added and the memory resource
controller selects this config option.
This patch also adds cgroup callbacks to notify subsystems when mm->owner
changes. The mm_cgroup_changed callback is called with the task_lock() of
the new task held and is called just prior to changing the mm->owner.
I am indebted to Paul Menage for the several reviews of this patchset and
helping me make it lighter and simpler.
This patch was tested on a powerpc box, it was compiled with both the
MM_OWNER config turned on and off.
After the thread group leader exits, it's moved to init_css_state by
cgroup_exit(), thus all future charges from runnings threads would be
redirected to the init_css_set's subsystem.
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Sudhir Kumar <skumar@linux.vnet.ibm.com>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: Hirokazu Takahashi <taka@valinux.co.jp>
Cc: David Rientjes <rientjes@google.com>,
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/cgroup.c')
-rw-r--r-- | kernel/cgroup.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index abc4337..b9d467d 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -119,6 +119,7 @@ static int root_count; * be called. */ static int need_forkexit_callback; +static int need_mm_owner_callback __read_mostly; /* convenient tests for these bits */ inline int cgroup_is_removed(const struct cgroup *cgrp) @@ -2498,6 +2499,7 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss) init_css_set.subsys[ss->subsys_id] = dummytop->subsys[ss->subsys_id]; need_forkexit_callback |= ss->fork || ss->exit; + need_mm_owner_callback |= !!ss->mm_owner_changed; /* At system boot, before all subsystems have been * registered, no tasks have been forked, so we don't @@ -2748,6 +2750,34 @@ void cgroup_fork_callbacks(struct task_struct *child) } } +#ifdef CONFIG_MM_OWNER +/** + * cgroup_mm_owner_callbacks - run callbacks when the mm->owner changes + * @p: the new owner + * + * Called on every change to mm->owner. mm_init_owner() does not + * invoke this routine, since it assigns the mm->owner the first time + * and does not change it. + */ +void cgroup_mm_owner_callbacks(struct task_struct *old, struct task_struct *new) +{ + struct cgroup *oldcgrp, *newcgrp; + + if (need_mm_owner_callback) { + int i; + for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) { + struct cgroup_subsys *ss = subsys[i]; + oldcgrp = task_cgroup(old, ss->subsys_id); + newcgrp = task_cgroup(new, ss->subsys_id); + if (oldcgrp == newcgrp) + continue; + if (ss->mm_owner_changed) + ss->mm_owner_changed(ss, oldcgrp, newcgrp); + } + } +} +#endif /* CONFIG_MM_OWNER */ + /** * cgroup_post_fork - called on a new task after adding it to the task list * @child: the task in question |