Re: [PATCH v2 3/4] mm: /proc/sys/vm/stat_refresh skip checking known negative stats

On Mon, Mar 01, 2021 at 10:03:26PM -0800, Hugh Dickins wrote: > vmstat_refresh() can occasionally catch nr_zone_write_pending and > nr_writeback when they are transiently negative. The reason is partly > that the interrupt which decrements them in test_clear_page_writeback() > can come in before

[PATCH v2 3/4] mm: /proc/sys/vm/stat_refresh skip checking known negative stats

vmstat_refresh() can occasionally catch nr_zone_write_pending and nr_writeback when they are transiently negative. The reason is partly that the interrupt which decrements them in test_clear_page_writeback() can come in before __test_set_page_writeback() got to increment them; but transient