mm: fix oom_kill event handling

Commit e27be240df ("mm: memcg: make sure memory.events is uptodate
when waking pollers") converted most of memcg event counters to
per-memcg atomics, which made them less confusing for a user.  The
"oom_kill" counter remained untouched, so now it behaves differently
than other counters (including "oom").  This adds nothing but confusion.

Let's fix this by adding the MEMCG_OOM_KILL event, and follow the
MEMCG_OOM approach.

This also removes a hack from count_memcg_event_mm(), introduced earlier
specially for the OOM_KILL counter.

[akpm@linux-foundation.org: fix for droppage of memcg-replace-mm-owner-with-mm-memcg.patch]
Link: http://lkml.kernel.org/r/20180508124637.29984-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Roman Gushchin 2018-06-14 15:28:05 -07:00 committed by Linus Torvalds
parent d7dc899abe
commit fe6bdfc8e1
3 changed files with 27 additions and 7 deletions

View File

@ -53,6 +53,7 @@ enum memcg_memory_event {
MEMCG_HIGH,
MEMCG_MAX,
MEMCG_OOM,
MEMCG_OOM_KILL,
MEMCG_SWAP_MAX,
MEMCG_SWAP_FAIL,
MEMCG_NR_MEMORY_EVENTS,
@ -720,11 +721,8 @@ static inline void count_memcg_event_mm(struct mm_struct *mm,
rcu_read_lock();
memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
if (likely(memcg)) {
if (likely(memcg))
count_memcg_events(memcg, idx, 1);
if (idx == OOM_KILL)
cgroup_file_notify(&memcg->events_file);
}
rcu_read_unlock();
}
@ -735,6 +733,21 @@ static inline void memcg_memory_event(struct mem_cgroup *memcg,
cgroup_file_notify(&memcg->events_file);
}
static inline void memcg_memory_event_mm(struct mm_struct *mm,
enum memcg_memory_event event)
{
struct mem_cgroup *memcg;
if (mem_cgroup_disabled())
return;
rcu_read_lock();
memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
if (likely(memcg))
memcg_memory_event(memcg, event);
rcu_read_unlock();
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
void mem_cgroup_split_huge_fixup(struct page *head);
#endif
@ -756,6 +769,11 @@ static inline void memcg_memory_event(struct mem_cgroup *memcg,
{
}
static inline void memcg_memory_event_mm(struct mm_struct *mm,
enum memcg_memory_event event)
{
}
static inline enum mem_cgroup_protection mem_cgroup_protected(
struct mem_cgroup *root, struct mem_cgroup *memcg)
{

View File

@ -3550,7 +3550,8 @@ static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v)
seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable);
seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom);
seq_printf(sf, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL));
seq_printf(sf, "oom_kill %lu\n",
atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL]));
return 0;
}
@ -5239,7 +5240,8 @@ static int memory_events_show(struct seq_file *m, void *v)
atomic_long_read(&memcg->memory_events[MEMCG_MAX]));
seq_printf(m, "oom %lu\n",
atomic_long_read(&memcg->memory_events[MEMCG_OOM]));
seq_printf(m, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL));
seq_printf(m, "oom_kill %lu\n",
atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL]));
return 0;
}

View File

@ -913,7 +913,7 @@ static void oom_kill_process(struct oom_control *oc, const char *message)
/* Raise event before sending signal: task reaper must see this */
count_vm_event(OOM_KILL);
count_memcg_event_mm(mm, OOM_KILL);
memcg_memory_event_mm(mm, MEMCG_OOM_KILL);
/*
* We should send SIGKILL before granting access to memory reserves