Introduce a per-memory-cgroup oom_score_adj setting. A read-write single value file which exits on non-root cgroups. The default is "0".
It will have a similar meaning to a per-process value, available via /proc/<pid>/oom_score_adj. Should be in a range [-1000, 1000]. Signed-off-by: Roman Gushchin <g...@fb.com> Cc: Tejun Heo <t...@kernel.org> Cc: Johannes Weiner <han...@cmpxchg.org> Cc: Li Zefan <lize...@huawei.com> Cc: Michal Hocko <mho...@kernel.org> Cc: Vladimir Davydov <vdavydov....@gmail.com> Cc: Tetsuo Handa <penguin-ker...@i-love.sakura.ne.jp> Cc: kernel-t...@fb.com Cc: cgro...@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-ker...@vger.kernel.org Cc: linux...@kvack.org --- include/linux/memcontrol.h | 3 +++ mm/memcontrol.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 39 insertions(+) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 8a308c9..818a42e 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -198,6 +198,9 @@ struct mem_cgroup { /* kill all tasks below in case of OOM */ bool oom_kill_all_tasks; + /* OOM kill score adjustment */ + short oom_score_adj; + /* handle for "memory.events" */ struct cgroup_file events_file; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index d4ffa79..f979ac7 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5183,6 +5183,36 @@ static ssize_t memory_oom_kill_all_tasks_write(struct kernfs_open_file *of, return nbytes; } +static int memory_oom_score_adj_show(struct seq_file *m, void *v) +{ + struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); + short oom_score_adj = memcg->oom_score_adj; + + seq_printf(m, "%d\n", oom_score_adj); + + return 0; +} + +static ssize_t memory_oom_score_adj_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); + int oom_score_adj; + int err; + + err = kstrtoint(strstrip(buf), 0, &oom_score_adj); + if (err) + return err; + + if (oom_score_adj < OOM_SCORE_ADJ_MIN || + oom_score_adj > OOM_SCORE_ADJ_MAX) + return -EINVAL; + + memcg->oom_score_adj = (short)oom_score_adj; + + return nbytes; +} + static int memory_events_show(struct seq_file *m, void *v) { struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); @@ -5298,6 +5328,12 @@ static struct cftype memory_files[] = { .write = memory_oom_kill_all_tasks_write, }, { + .name = "oom_score_adj", + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = memory_oom_score_adj_show, + .write = memory_oom_score_adj_write, + }, + { .name = "events", .flags = CFTYPE_NOT_ON_ROOT, .file_offset = offsetof(struct mem_cgroup, events_file), -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html