From cf475ad28ac35cc9ba612d67158f29b73b38b05d Mon Sep 17 00:00:00 2001 From: Balbir Singh Date: Tue, 29 Apr 2008 01:00:16 -0700 Subject: 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 Cc: Pavel Emelianov Cc: Hugh Dickins Cc: Sudhir Kumar Cc: YAMAMOTO Takashi Cc: Hirokazu Takahashi Cc: David Rientjes , Cc: Balbir Singh Acked-by: KAMEZAWA Hiroyuki Acked-by: Pekka Enberg Reviewed-by: Paul Menage Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/cgroup.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/linux/cgroup.h') diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 095248082b7e..e155aa78d859 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -305,6 +305,12 @@ struct cgroup_subsys { struct cgroup *cgrp); void (*post_clone)(struct cgroup_subsys *ss, struct cgroup *cgrp); void (*bind)(struct cgroup_subsys *ss, struct cgroup *root); + /* + * This routine is called with the task_lock of mm->owner held + */ + void (*mm_owner_changed)(struct cgroup_subsys *ss, + struct cgroup *old, + struct cgroup *new); int subsys_id; int active; int disabled; @@ -390,4 +396,13 @@ static inline int cgroupstats_build(struct cgroupstats *stats, #endif /* !CONFIG_CGROUPS */ +#ifdef CONFIG_MM_OWNER +extern void +cgroup_mm_owner_callbacks(struct task_struct *old, struct task_struct *new); +#else /* !CONFIG_MM_OWNER */ +static inline void +cgroup_mm_owner_callbacks(struct task_struct *old, struct task_struct *new) +{ +} +#endif /* CONFIG_MM_OWNER */ #endif /* _LINUX_CGROUP_H */ -- cgit v1.2.3