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| author | Johannes Weiner <hannes@cmpxchg.org> | 2013-09-12 15:13:42 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-11-21 09:22:56 -0800 |
| commit | 11f34787b50ce71f66b85ad8790beaa5eee3f897 (patch) | |
| tree | adcde8d7963d1426991067916366ae3f5ec11c8a /include | |
| parent | ed368ae78e6eafc10368e97246610d676bec3060 (diff) | |
| download | lwn-11f34787b50ce71f66b85ad8790beaa5eee3f897.tar.gz lwn-11f34787b50ce71f66b85ad8790beaa5eee3f897.zip | |
mm: memcg: enable memcg OOM killer only for user faults
commit 519e52473ebe9db5cdef44670d5a97f1fd53d721 upstream.
System calls and kernel faults (uaccess, gup) can handle an out of memory
situation gracefully and just return -ENOMEM.
Enable the memcg OOM killer only for user faults, where it's really the
only option available.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: azurIt <azurit@pobox.sk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/memcontrol.h | 44 | ||||
| -rw-r--r-- | include/linux/sched.h | 3 |
2 files changed, 47 insertions, 0 deletions
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index d6183f06d8c1..2c911c95b1ac 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -124,6 +124,37 @@ extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, extern void mem_cgroup_replace_page_cache(struct page *oldpage, struct page *newpage); +/** + * mem_cgroup_toggle_oom - toggle the memcg OOM killer for the current task + * @new: true to enable, false to disable + * + * Toggle whether a failed memcg charge should invoke the OOM killer + * or just return -ENOMEM. Returns the previous toggle state. + */ +static inline bool mem_cgroup_toggle_oom(bool new) +{ + bool old; + + old = current->memcg_oom.may_oom; + current->memcg_oom.may_oom = new; + + return old; +} + +static inline void mem_cgroup_enable_oom(void) +{ + bool old = mem_cgroup_toggle_oom(true); + + WARN_ON(old == true); +} + +static inline void mem_cgroup_disable_oom(void) +{ + bool old = mem_cgroup_toggle_oom(false); + + WARN_ON(old == false); +} + #ifdef CONFIG_MEMCG_SWAP extern int do_swap_account; #endif @@ -347,6 +378,19 @@ static inline void mem_cgroup_end_update_page_stat(struct page *page, { } +static inline bool mem_cgroup_toggle_oom(bool new) +{ + return false; +} + +static inline void mem_cgroup_enable_oom(void) +{ +} + +static inline void mem_cgroup_disable_oom(void) +{ +} + static inline void mem_cgroup_inc_page_stat(struct page *page, enum mem_cgroup_page_stat_item idx) { diff --git a/include/linux/sched.h b/include/linux/sched.h index f87e9a8d364f..42a58ce480bc 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1411,6 +1411,9 @@ struct task_struct { unsigned long memsw_nr_pages; /* uncharged mem+swap usage */ } memcg_batch; unsigned int memcg_kmem_skip_account; + struct memcg_oom_info { + unsigned int may_oom:1; + } memcg_oom; #endif #ifdef CONFIG_HAVE_HW_BREAKPOINT atomic_t ptrace_bp_refcnt; |