On 11/20/2025 1:33 PM, Dev Jain wrote:
>
> On 20/11/25 12:20 pm, Shivank Garg wrote:
> SCAN_PAGE_NOT_CLEAN is confusing - NOT_CLEAN literally means dirty, so why
> not SCAN_PAGE_DIRTY?
> Or SCAN_PAGE_DIRTY_OR_UNDER_WRITEBACK? Since folio_test_writeback() is true
> as a result of
> the folio being dirty, maybe just SCAN_PAGE_DIRTY can do.
>
> Reviewed-by: Dev Jain <[email protected]>
>
Thanks for the review.
I chose not to use SCAN_PAGE_DIRTY because dirty and writeback have different
meanings[1]:
Dirty: Memory that is waiting to be written back to disk
Writeback: Memory that is actively being written back to disk
[1] https://www.kernel.org/doc/Documentation/filesystems/proc.txt
IIUC, a page under writeback is no longer dirty, so using SCAN_PAGE_DIRTY would
be misleading
for pages in the writeback state.
I considered SCAN_PAGE_DIRTY_OR_WRITEBACK initially but felt it was too long.
SCAN_PAGE_NOT_CLEAN covers both states that indicate the page is not in a
clean/stable
state suitable for collapse.
[1] https://www.kernel.org/doc/Documentation/filesystems/proc.txt
Thanks,
Shivank
