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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 > 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