Re: [PATCH 3/6] mm/zswap: stop lru list shrinking when encounter warm region

From: Chengming Zhou
Date: Fri Feb 02 2024 - 03:18:46 EST


On 2024/2/2 08:15, Yosry Ahmed wrote:
> On Thu, Feb 01, 2024 at 03:49:03PM +0000, Chengming Zhou wrote:
>> When the shrinker encounter an existing folio in swap cache, it means
>> we are shrinking into the warmer region. We should terminate shrinking
>> if we're in the dynamic shrinker context.
>>
>> This patch add LRU_STOP to support this, to avoid overshrinking.
>>
>> Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
>
> LGTM with one comment below.
>
> Reviewed-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
>
>> ---
>> include/linux/list_lru.h | 1 +
>> mm/list_lru.c | 3 +++
>> mm/zswap.c | 4 +++-
>> 3 files changed, 7 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h
>> index f2882a820690..5633e970144b 100644
>> --- a/include/linux/list_lru.h
>> +++ b/include/linux/list_lru.h
>> @@ -24,6 +24,7 @@ enum lru_status {
>> LRU_SKIP, /* item cannot be locked, skip */
>> LRU_RETRY, /* item not freeable. May drop the lock
>> internally, but has to return locked. */
>> + LRU_STOP, /* stop lru list walking */
>
> nit: Should we add "May drop the lock internally, but has to return
> locked" like LRU_RETRY and LRU_REMOVED_RETRY?

Right, will add.

Thanks.