Re: [PATCH v3] memcg: fix soft lockup in the OOM process

From: Chen Ridong
Date: Tue Jan 14 2025 - 07:19:51 EST




On 2025/1/14 17:30, Michal Hocko wrote:
> On Tue 14-01-25 10:20:28, Vlastimil Babka wrote:
>> On 1/14/25 09:40, Michal Hocko wrote:
>>> On Mon 13-01-25 19:45:46, Andrew Morton wrote:
> [...]
>>>>> For global OOM, system is likely to struggle, do we have to do some
>>>>> works to suppress RCU detete?
>>>>
>>>> rcu_cpu_stall_reset()?
>>>
>>> Do we really care about those? The code to iterate over all processes
>>> under RCU is there (basically) since ever and yet we do not seem to have
>>> many reports of stalls? Chen's situation is specific to memcg OOM and
>>> touching the global case was mostly for consistency reasons.
>>
>> Then I'd rather not touch the global case then if it's theoretical?
>
> No strong opinion on this on my side. The only actual reason
> touch_softlockup_watchdog is there is becuase it originally had
> incorrectly cond_resched there. If half silencing (soft lock up
> detector only) disturbs people then let's just drop that hunk.

So do I. If there are no other opinions, I will drop it.

Best regards,
Ridong