Re: [PATCH] mm/vmscan: Fix hard LOCKUP in function isolate_lru_folios

[liuye]

On 2024/9/25 上午8:22, Andrew Morton wrote:
> On Wed, 14 Aug 2024 17:18:25 +0800 liuye <liuye@xxxxxxxxxx> wrote:
> 
>> @@ -1669,10 +1670,12 @@ static unsigned long isolate_lru_folios(unsigned long nr_to_scan,
>>  		nr_pages = folio_nr_pages(folio);
>>  		total_scan += nr_pages;
>>  
>> -		if (folio_zonenum(folio) > sc->reclaim_idx ||
>> -				skip_cma(folio, sc)) {
>> +		/* Using max_nr_skipped to prevent hard LOCKUP*/
>> +		if ((max_nr_skipped < SWAP_CLUSTER_MAX_SKIPPED) &&
>> +			(folio_zonenum(folio) > sc->reclaim_idx || skip_cma(folio, sc))) {
>>  			nr_skipped[folio_zonenum(folio)] += nr_pages;
>>  			move_to = &folios_skipped;
>> +			max_nr_skipped++;
>>  			goto move;
> 
> This hunk is not applicable to current mainline.
> 

Please see the PATCH v2 in link [1], and the related discussion in link [2].
Then please explain why it is not applicable,thank you.

[1]:https://lore.kernel.org/all/20240919021443.9170-1-liuye@xxxxxxxxxx/
[2]:https://lore.kernel.org/all/e878653e-d380-81c2-90a8-fd2d1d4e7287@xxxxxxxxxx/

Thanks,
liuye