Miaohe Lin <linmiaohe@xxxxxxxxxx> writes:
> On 2022/4/1 11:20, Huang, Ying wrote:
>> Miaohe Lin <linmiaohe@xxxxxxxxxx> writes:
>>
>>> Use helper folio_is_file_lru() to check whether folio is file lru. Minor
>>> readability improvement.
>>>
>>> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>>> ---
>>> mm/vmscan.c | 4 ++--
>>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/mm/vmscan.c b/mm/vmscan.c
>>> index ebd8ffb63673..31e95d627448 100644
>>> --- a/mm/vmscan.c
>>> +++ b/mm/vmscan.c
>>> @@ -1411,14 +1411,14 @@ static enum page_references folio_check_references(struct folio *folio,
>>> /*
>>> * Activate file-backed executable folios after first usage.
>>> */
>>> - if ((vm_flags & VM_EXEC) && !folio_test_swapbacked(folio))
>>> + if ((vm_flags & VM_EXEC) && folio_is_file_lru(folio))
>>
>> I think that this should be converted to
>>
>> if ((vm_flags & VM_EXEC)))
>>
>> We should activate swap-backed executable folios (e.g. tmpfs) after
>> first usage too.
>>
>
> Dig into the git history, we can found that commit c909e99364c8 ("vmscan: activate executable pages after first usage")
> activate swap-backed executable folios after first usage too. But later swap-backed executable folios is not activated
> via commit b518154e59aa ("mm/vmscan: protect the workingset on anonymous LRU") to pretect the workingset from anonymous
> LRU. So above change might not be wanted. Or am I miss something?
I think we should restore the original behavior to protect swap backed
executable folios too.
Hi, Kim,
What do you think about this?
Best Regards,
Huang, Ying
> Many thanks.
>
>> Best Regards,
>> Huang, Ying
>>
>>> return PAGEREF_ACTIVATE;
>>>
>>> return PAGEREF_KEEP;
>>> }
>>>
>>> /* Reclaim if clean, defer dirty folios to writeback */
>>> - if (referenced_folio && !folio_test_swapbacked(folio))
>>> + if (referenced_folio && folio_is_file_lru(folio))
>>> return PAGEREF_RECLAIM_CLEAN;
>>>
>>> return PAGEREF_RECLAIM;
>> .
>>
