diff options
| -rw-r--r-- | mm/vmscan.c | 16 |
1 files changed, 6 insertions, 10 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index e61445dce04e..8286938c70de 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -973,22 +973,18 @@ static unsigned long shrink_page_list(struct list_head *page_list, * caller can stall after page list has been processed. * * 2) Global or new memcg reclaim encounters a page that is - * not marked for immediate reclaim or the caller does not - * have __GFP_IO. In this case mark the page for immediate + * not marked for immediate reclaim, or the caller does not + * have __GFP_FS (or __GFP_IO if it's simply going to swap, + * not to fs). In this case mark the page for immediate * reclaim and continue scanning. * - * __GFP_IO is checked because a loop driver thread might + * Require may_enter_fs because we would wait on fs, which + * may not have submitted IO yet. And the loop driver might * enter reclaim, and deadlock if it waits on a page for * which it is needed to do the write (loop masks off * __GFP_IO|__GFP_FS for this reason); but more thought * would probably show more reasons. * - * Don't require __GFP_FS, since we're not going into the - * FS, just waiting on its writeback completion. Worryingly, - * ext4 gfs2 and xfs allocate pages with - * grab_cache_page_write_begin(,,AOP_FLAG_NOFS), so testing - * may_enter_fs here is liable to OOM on them. - * * 3) Legacy memcg encounters a page that is not already marked * PageReclaim. memcg does not have any dirty pages * throttling so we could easily OOM just because too many @@ -1005,7 +1001,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, /* Case 2 above */ } else if (sane_reclaim(sc) || - !PageReclaim(page) || !(sc->gfp_mask & __GFP_IO)) { + !PageReclaim(page) || !may_enter_fs) { /* * This is slightly racy - end_page_writeback() * might have just cleared PageReclaim, then |