Re: [PATCH] mm, oom: distinguish blockable mode for mmu notifiers

Michal Hocko
2018-07-25T06:17:22Z

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