On 04.06.24 12:48, yangge1116@xxxxxxx wrote:
From: yangge <yangge1116@xxxxxxx> If a page is added in pagevec, its ref count increases one, remove the page from pagevec decreases one. Page migration requires the page is not referenced by others except page mapping. Before migrating a page, we should try to drain the page from pagevec in case the page is in it, however, folio_test_lru() is not sufficient to tell whether the page is in pagevec or not, if the page is in pagevec, the migration will fail. Remove the condition and drain lru once to ensure the page is not referenced by pagevec.
What you are saying is that we might have a page on which folio_test_lru() succeeds, that was added to one of the cpu_fbatches, correct?
Can you describe under which circumstances that happens? -- Cheers, David / dhildenb
