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| author | Ming Lei <ming.lei@redhat.com> | 2022-04-20 22:31:10 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-05-02 10:07:42 -0600 |
| commit | 9650b453a3d4b1b8ed4ea8bcb9b40109608d1faf (patch) | |
| tree | c43dfc5033aec249e22536898a6a043390df7782 /mm/page_io.c | |
| parent | e233fe1aa02815f38588a5a965a197bbcabfb125 (diff) | |
| download | linux-9650b453a3d4b1b8ed4ea8bcb9b40109608d1faf.tar.gz | |
block: ignore RWF_HIPRI hint for sync dio
So far bio is marked as REQ_POLLED if RWF_HIPRI/IOCB_HIPRI is passed from userspace sync io interface, then block layer tries to poll until the bio is completed. But the current implementation calls blk_io_schedule() if bio_poll() returns 0, and this way causes io hang or timeout easily. But looks no one reports this kind of issue, which should have been triggered in normal io poll sanity test or blktests block/007 as observed by Changhui, that means it is very likely that no one uses it or no one cares it. Also after io_uring is invented, io poll for sync dio becomes legacy interface. So ignore RWF_HIPRI hint for sync dio. CC: linux-mm@kvack.org Cc: linux-xfs@vger.kernel.org Reported-by: Changhui Zhong <czhong@redhat.com> Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Tested-by: Changhui Zhong <czhong@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220420143110.2679002-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'mm/page_io.c')
| -rw-r--r-- | mm/page_io.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/mm/page_io.c b/mm/page_io.c index 89fbf3cae30f..3fbdab6a940e 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -360,7 +360,6 @@ int swap_readpage(struct page *page, bool synchronous) * attempt to access it in the page fault retry time check. */ if (synchronous) { - bio->bi_opf |= REQ_POLLED; get_task_struct(current); bio->bi_private = current; } @@ -372,8 +371,7 @@ int swap_readpage(struct page *page, bool synchronous) if (!READ_ONCE(bio->bi_private)) break; - if (!bio_poll(bio, NULL, 0)) - blk_io_schedule(); + blk_io_schedule(); } __set_current_state(TASK_RUNNING); bio_put(bio); |