Re: [PATCH 2/3] mm: use filemap_range_needs_writeback() for O_DIRECT reads
flat view
From: Jan Kara <jack@suse.cz>
Date: 2021-02-24 17:24:23
Also in:
linux-fsdevel
On Wed 24-02-21 09:44:54, Jens Axboe wrote:
For the generic page cache read helper, use the better variant of checking for the need to call filemap_write_and_wait_range() when doing O_DIRECT reads. This avoids falling back to the slow path for IOCB_NOWAIT, if there are no pages to wait for (or write out). Signed-off-by: Jens Axboe <axboe@kernel.dk> --- mm/filemap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
Looks good to me. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza
quoted hunk ↗ jump to hunk
diff --git a/mm/filemap.c b/mm/filemap.c index 13338f877677..77f1b527541e 100644 --- a/mm/filemap.c +++ b/mm/filemap.c@@ -2645,8 +2645,8 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) size = i_size_read(inode); if (iocb->ki_flags & IOCB_NOWAIT) { - if (filemap_range_has_page(mapping, iocb->ki_pos, - iocb->ki_pos + count - 1)) + if (filemap_range_needs_writeback(mapping, iocb->ki_pos, + iocb->ki_pos + count - 1)) return -EAGAIN; } else { retval = filemap_write_and_wait_range(mapping,-- 2.30.0
-- Jan Kara [off-list ref] SUSE Labs, CR