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Date:   Wed, 25 Jul 2018 08:17:22 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Andrew Morton <akpm@linux-foundation.org>
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Subject: Re: [PATCH] mm, oom: distinguish blockable mode for mmu notifiers
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On Tue 24-07-18 12:53:07, Andrew Morton wrote:
[...]
> > On top of that the proposed cleanup looks as follows:
> > 
> 
> Looks good to me.  Seems a bit strange that we omit the pr_info()
> output if the mm was partially reaped - people would still want to know
> this?   Not very important though.

I think that having a single output once we are done is better but I do
not have a strong opinion on this.

Btw. here is the changelog for the cleanup.

"
Andrew has noticed someinconsistencies in oom_reap_task_mm. Notably
 - Undocumented return value.

 - comment "failed to reap part..." is misleading - sounds like it's
   referring to something which happened in the past, is in fact
   referring to something which might happen in the future.

 - fails to call trace_finish_task_reaping() in one case

 - code duplication.

 - Increases mmap_sem hold time a little by moving
   trace_finish_task_reaping() inside the locked region.  So sue me ;)

 - Sharing the finish: path means that the trace event won't
   distinguish between the two sources of finishing.

Add a short explanation for the return value and fix the rest by
reorganizing the function a bit to have unified function exit paths.

Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michal Hocko <mhocko@suse.com>
"

-- 
Michal Hocko
SUSE Labs