| Message ID | 20210224164455.1096727-3-axboe@kernel.dk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Improve IOCB_NOWAIT O_DIRECT reads | expand |
On Wed, Feb 24, 2021 at 09:44:54AM -0700, 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> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
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 > > 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 >
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,
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(-)