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>
This commit is contained in:
Balbir Singh 2008-04-29 01:00:16 -07:00 • committed by Linus Torvalds
commit cf475ad28a
11 changed files with 169 additions and 41 deletions

View file

@ -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 */

View file

@ -27,9 +27,6 @@ struct mm_struct;
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
extern void mm_init_cgroup(struct mm_struct *mm, struct task_struct *p);
extern void mm_free_cgroup(struct mm_struct *mm);
#define page_reset_bad_cgroup(page) ((page)->page_cgroup = 0)
extern struct page_cgroup *page_get_page_cgroup(struct page *page);
@ -48,8 +45,10 @@ extern unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
extern void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask);
int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem);
extern struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
#define mm_match_cgroup(mm, cgroup) \
((cgroup) == rcu_dereference((mm)->mem_cgroup))
((cgroup) == mem_cgroup_from_task((mm)->owner))
extern int mem_cgroup_prepare_migration(struct page *page);
extern void mem_cgroup_end_migration(struct page *page);
@ -73,15 +72,6 @@ extern long mem_cgroup_calc_reclaim_inactive(struct mem_cgroup *mem,
struct zone *zone, int priority);
#else /* CONFIG_CGROUP_MEM_RES_CTLR */
static inline void mm_init_cgroup(struct mm_struct *mm,
struct task_struct *p)
{
}
static inline void mm_free_cgroup(struct mm_struct *mm)
{
}
static inline void page_reset_bad_cgroup(struct page *page)
{
}

View file

@ -225,8 +225,9 @@ struct mm_struct {
/* aio bits */
rwlock_t ioctx_list_lock; /* aio lock */
struct kioctx *ioctx_list;
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
struct mem_cgroup *mem_cgroup;
#ifdef CONFIG_MM_OWNER
struct task_struct *owner; /* The thread group leader that */
/* owns the mm_struct. */
#endif
};

View file

@ -2148,6 +2148,19 @@ static inline void migration_init(void)
#define TASK_SIZE_OF(tsk) TASK_SIZE
#endif
#ifdef CONFIG_MM_OWNER
extern void mm_update_next_owner(struct mm_struct *mm);
extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
#else
static inline void mm_update_next_owner(struct mm_struct *mm)
{
}
static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
{
}
#endif /* CONFIG_MM_OWNER */
#endif /* __KERNEL__ */
#endif