Re: [RFC 01/13] mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode

2016-05-11 Thread Michal Hocko
On Tue 10-05-16 09:35:51, Vlastimil Babka wrote: > From: Hugh Dickins > > At present MIGRATE_SYNC_LIGHT is allowing __isolate_lru_page() to > isolate a PageWriteback page, which __unmap_and_move() then rejects > with -EBUSY: of course the writeback might complete in between, but > that's not what

[RFC 01/13] mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode

2016-05-10 Thread Vlastimil Babka
From: Hugh Dickins At present MIGRATE_SYNC_LIGHT is allowing __isolate_lru_page() to isolate a PageWriteback page, which __unmap_and_move() then rejects with -EBUSY: of course the writeback might complete in between, but that's not what we usually expect, so probably better not to isolate it. Si