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

2021-03-01 Thread Roman Gushchin
Mon, Mar 01, 2021 at 02:08:17PM -0800, Hugh Dickins wrote: > On Sun, 28 Feb 2021, Roman Gushchin wrote: > > On Thu, Feb 25, 2021 at 03:14:03PM -0800, Hugh Dickins wrote: > > > vmstat_refresh() can occasionally catch nr_zone_write_pending and > > > nr_writeback when they are transiently negative.

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

2021-03-01 Thread Hugh Dickins
On Sun, 28 Feb 2021, Roman Gushchin wrote: > On Thu, Feb 25, 2021 at 03:14:03PM -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

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

2021-02-28 Thread Roman Gushchin
On Thu, Feb 25, 2021 at 03:14:03PM -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 3/4] mm: /proc/sys/vm/stat_refresh skip checking known negative stats

2021-02-25 Thread Hugh Dickins
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