Re: [PATCH] mm: compaction: early termination in compact_nodes()

[Kefeng Wang <wangkefeng.wang@huawei.com>]

On 2024/2/22 6:34, Andrew Morton wrote:
> On Sat, 17 Feb 2024 10:55:10 +0800 Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> 
>> On 2024/2/12 22:22, David Hildenbrand wrote:
>>> On 08.02.24 22:14, Andrew Morton wrote:
>>>> On Thu, 8 Feb 2024 10:25:08 +0800 Kefeng Wang
>>>> <wangkefeng.wang@huawei.com> wrote:
>>>>
>>>>> No need to continue try compact memory if pending fatal signal,
>>>>> allow loop termination earlier in compact_nodes().
>>>>
>>>> Seems sensible, but...  why?  Is there some problem which we can
>>>> demonstrate with the existing code?  In other words, does this change
>>>> provide any observable benefit under any circumstances?
>>>
>>> I'd also be curious why the existing fatal_signal_pending() calls are
>>> insufficient.
>>
>> The existing fatal_signal_pending() does make compact_zone() breakout of
>> the while loop, but it still enter the next zone/next nid, and some
>> unnecessary functions(eg, lru_add_drain) called, no observable benefit
>> from test, it is just found from code inspection when refactor
> 
> Fair enough.  I added the above words to the changelog (this material
> should have been communicated in the original!) and I'll plan to move
> this change into mm-stable next week unless someone stops me.
Indeed, thanks for the update, you're so kind.