* + mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch added to -mm tree
@ 2016-01-12 21:25 akpm
2016-01-13 15:50 ` Michal Hocko
0 siblings, 1 reply; 2+ messages in thread
From: akpm @ 2016-01-12 21:25 UTC (permalink / raw
To: hannes, andrea, hughd, kirill.shutemov, mgorman, mhocko, oleg,
penguin-kernel, riel, rientjes, sasha.levin, mm-commits
The patch titled
Subject: mm/oom_kill.c: don't skip PF_EXITING tasks when searching for a victim
has been added to the -mm tree. Its filename is
mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Johannes Weiner <hannes@cmpxchg.org>
Subject: mm/oom_kill.c: don't skip PF_EXITING tasks when searching for a victim
When the OOM killer scans tasks and encounters a PF_EXITING one, it
force-selects that one regardless of the score. Is there a possibility
that the task might hang after it has set PF_EXITING? In that case the
OOM killer should be able to move on to the next task.
Frankly, I don't even know why we check for exiting tasks in the OOM
killer. We've tried direct reclaim at least 15 times by the time we
decide the system is OOM, there was plenty of time to exit and free
memory; and a task might exit voluntarily right after we issue a kill.
This is testing pure noise.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/oom_kill.c | 3 ---
1 file changed, 3 deletions(-)
diff -puN mm/oom_kill.c~mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim mm/oom_kill.c
--- a/mm/oom_kill.c~mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim
+++ a/mm/oom_kill.c
@@ -292,9 +292,6 @@ enum oom_scan_t oom_scan_process_thread(
if (oom_task_origin(task))
return OOM_SCAN_SELECT;
- if (task_will_free_mem(task) && !is_sysrq_oom(oc))
- return OOM_SCAN_ABORT;
-
return OOM_SCAN_OK;
}
_
Patches currently in -mm which might be from hannes@cmpxchg.org are
mm-page_alloc-generalize-the-dirty-balance-reserve.patch
proc-meminfo-estimate-available-memory-more-conservatively.patch
mm-memcontrol-export-root_mem_cgroup.patch
net-tcp_memcontrol-properly-detect-ancestor-socket-pressure.patch
net-tcp_memcontrol-remove-bogus-hierarchy-pressure-propagation.patch
net-tcp_memcontrol-protect-all-tcp_memcontrol-calls-by-jump-label.patch
net-tcp_memcontrol-remove-dead-per-memcg-count-of-allocated-sockets.patch
net-tcp_memcontrol-simplify-the-per-memcg-limit-access.patch
net-tcp_memcontrol-sanitize-tcp-memory-accounting-callbacks.patch
net-tcp_memcontrol-simplify-linkage-between-socket-and-page-counter.patch
net-tcp_memcontrol-simplify-linkage-between-socket-and-page-counter-fix.patch
mm-memcontrol-generalize-the-socket-accounting-jump-label.patch
mm-memcontrol-do-not-account-memoryswap-on-unified-hierarchy.patch
mm-memcontrol-move-socket-code-for-unified-hierarchy-accounting.patch
mm-memcontrol-account-socket-memory-in-unified-hierarchy-memory-controller.patch
mm-memcontrol-hook-up-vmpressure-to-socket-pressure.patch
mm-memcontrol-switch-to-the-updated-jump-label-api.patch
mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch
mm-memcontrol-drop-unused-css-argument-in-memcg_init_kmem.patch
mm-memcontrol-remove-double-kmem-page_counter-init.patch
mm-memcontrol-give-the-kmem-states-more-descriptive-names.patch
mm-memcontrol-group-kmem-init-and-exit-functions-together.patch
mm-memcontrol-separate-kmem-code-from-legacy-tcp-accounting-code.patch
mm-memcontrol-move-kmem-accounting-code-to-config_memcg.patch
mm-memcontrol-move-kmem-accounting-code-to-config_memcg-v2.patch
mm-memcontrol-move-kmem-accounting-code-to-config_memcg-fix.patch
mm-memcontrol-account-kmem-consumers-in-cgroup2-memory-controller.patch
mm-memcontrol-introduce-config_memcg_legacy_kmem.patch
mm-memcontrol-reign-in-the-config-space-madness.patch
mm-memcontrol-flatten-struct-cg_proto.patch
mm-memcontrol-clean-up-alloc-online-offline-free-functions.patch
mm-memcontrol-clean-up-alloc-online-offline-free-functions-fix.patch
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: + mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch added to -mm tree
2016-01-12 21:25 + mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch added to -mm tree akpm
@ 2016-01-13 15:50 ` Michal Hocko
0 siblings, 0 replies; 2+ messages in thread
From: Michal Hocko @ 2016-01-13 15:50 UTC (permalink / raw
To: akpm
Cc: hannes, andrea, hughd, kirill.shutemov, mgorman, oleg,
penguin-kernel, riel, rientjes, sasha.levin, mm-commits, linux-mm
Thanks for having this separately. I agree with David that this is
_safer_ to route in the same series with the oom reaper but I guess the
risk to have it separare is quite low if measurable at all.
On Tue 12-01-16 13:25:20, Andrew Morton wrote:
[...]
> From: Johannes Weiner <hannes@cmpxchg.org>
> Subject: mm/oom_kill.c: don't skip PF_EXITING tasks when searching for a victim
>
> When the OOM killer scans tasks and encounters a PF_EXITING one, it
> force-selects that one regardless of the score. Is there a possibility
> that the task might hang after it has set PF_EXITING? In that case the
> OOM killer should be able to move on to the next task.
>
> Frankly, I don't even know why we check for exiting tasks in the OOM
> killer. We've tried direct reclaim at least 15 times by the time we
> decide the system is OOM, there was plenty of time to exit and free
> memory; and a task might exit voluntarily right after we issue a kill.
> This is testing pure noise.
>
> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> Cc: Michal Hocko <mhocko@suse.com>
> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Cc: Mel Gorman <mgorman@suse.de>
> Cc: David Rientjes <rientjes@google.com>
> Cc: Oleg Nesterov <oleg@redhat.com>
> Cc: Hugh Dickins <hughd@google.com>
> Cc: Andrea Argangeli <andrea@kernel.org>
> Cc: Rik van Riel <riel@redhat.com>
> Cc: Sasha Levin <sasha.levin@oracle.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
> ---
>
> mm/oom_kill.c | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff -puN mm/oom_kill.c~mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim mm/oom_kill.c
> --- a/mm/oom_kill.c~mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim
> +++ a/mm/oom_kill.c
> @@ -292,9 +292,6 @@ enum oom_scan_t oom_scan_process_thread(
> if (oom_task_origin(task))
> return OOM_SCAN_SELECT;
>
> - if (task_will_free_mem(task) && !is_sysrq_oom(oc))
> - return OOM_SCAN_ABORT;
> -
> return OOM_SCAN_OK;
> }
>
> _
>
> Patches currently in -mm which might be from hannes@cmpxchg.org are
>
> mm-page_alloc-generalize-the-dirty-balance-reserve.patch
> proc-meminfo-estimate-available-memory-more-conservatively.patch
> mm-memcontrol-export-root_mem_cgroup.patch
> net-tcp_memcontrol-properly-detect-ancestor-socket-pressure.patch
> net-tcp_memcontrol-remove-bogus-hierarchy-pressure-propagation.patch
> net-tcp_memcontrol-protect-all-tcp_memcontrol-calls-by-jump-label.patch
> net-tcp_memcontrol-remove-dead-per-memcg-count-of-allocated-sockets.patch
> net-tcp_memcontrol-simplify-the-per-memcg-limit-access.patch
> net-tcp_memcontrol-sanitize-tcp-memory-accounting-callbacks.patch
> net-tcp_memcontrol-simplify-linkage-between-socket-and-page-counter.patch
> net-tcp_memcontrol-simplify-linkage-between-socket-and-page-counter-fix.patch
> mm-memcontrol-generalize-the-socket-accounting-jump-label.patch
> mm-memcontrol-do-not-account-memoryswap-on-unified-hierarchy.patch
> mm-memcontrol-move-socket-code-for-unified-hierarchy-accounting.patch
> mm-memcontrol-account-socket-memory-in-unified-hierarchy-memory-controller.patch
> mm-memcontrol-hook-up-vmpressure-to-socket-pressure.patch
> mm-memcontrol-switch-to-the-updated-jump-label-api.patch
> mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch
> mm-memcontrol-drop-unused-css-argument-in-memcg_init_kmem.patch
> mm-memcontrol-remove-double-kmem-page_counter-init.patch
> mm-memcontrol-give-the-kmem-states-more-descriptive-names.patch
> mm-memcontrol-group-kmem-init-and-exit-functions-together.patch
> mm-memcontrol-separate-kmem-code-from-legacy-tcp-accounting-code.patch
> mm-memcontrol-move-kmem-accounting-code-to-config_memcg.patch
> mm-memcontrol-move-kmem-accounting-code-to-config_memcg-v2.patch
> mm-memcontrol-move-kmem-accounting-code-to-config_memcg-fix.patch
> mm-memcontrol-account-kmem-consumers-in-cgroup2-memory-controller.patch
> mm-memcontrol-introduce-config_memcg_legacy_kmem.patch
> mm-memcontrol-reign-in-the-config-space-madness.patch
> mm-memcontrol-flatten-struct-cg_proto.patch
> mm-memcontrol-clean-up-alloc-online-offline-free-functions.patch
> mm-memcontrol-clean-up-alloc-online-offline-free-functions-fix.patch
>
--
Michal Hocko
SUSE Labs
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2016-01-13 15:50 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-01-12 21:25 + mm-oom_killc-dont-skip-pf_exiting-tasks-when-searching-for-a-victim.patch added to -mm tree akpm
2016-01-13 15:50 ` Michal Hocko
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.