From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 30 May 2018 11:00:21 -0700 From: "Darrick J. Wong" To: Christoph Hellwig Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 16/18] xfs: refactor the tail of xfs_writepage_map Message-ID: <20180530180021.GT837@magnolia> References: <20180530100013.31358-1-hch@lst.de> <20180530100013.31358-17-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180530100013.31358-17-hch@lst.de> Sender: owner-linux-mm@kvack.org List-ID: On Wed, May 30, 2018 at 12:00:11PM +0200, Christoph Hellwig wrote: > Rejuggle how we deal with the different error vs non-error and have > ioends vs not have ioend cases to keep the fast path streamlined, and > the duplicate code at a minimum. > > Signed-off-by: Christoph Hellwig Looks ok, Reviewed-by: Darrick J. Wong --D > --- > fs/xfs/xfs_aops.c | 65 +++++++++++++++++++++++------------------------ > 1 file changed, 32 insertions(+), 33 deletions(-) > > diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c > index 38021023131e..ac417ef326a9 100644 > --- a/fs/xfs/xfs_aops.c > +++ b/fs/xfs/xfs_aops.c > @@ -873,7 +873,14 @@ xfs_writepage_map( > * submission of outstanding ioends on the writepage context so they are > * treated correctly on error. > */ > - if (count) { > + if (unlikely(error)) { > + if (!count) { > + xfs_aops_discard_page(page); > + ClearPageUptodate(page); > + unlock_page(page); > + goto done; > + } > + > /* > * If the page was not fully cleaned, we need to ensure that the > * higher layers come back to it correctly. That means we need > @@ -882,43 +889,35 @@ xfs_writepage_map( > * so another attempt to write this page in this writeback sweep > * will be made. > */ > - if (error) { > - set_page_writeback_keepwrite(page); > - } else { > - clear_page_dirty_for_io(page); > - set_page_writeback(page); > - } > - unlock_page(page); > - > - /* > - * Preserve the original error if there was one, otherwise catch > - * submission errors here and propagate into subsequent ioend > - * submissions. > - */ > - list_for_each_entry_safe(ioend, next, &submit_list, io_list) { > - int error2; > - > - list_del_init(&ioend->io_list); > - error2 = xfs_submit_ioend(wbc, ioend, error); > - if (error2 && !error) > - error = error2; > - } > - } else if (error) { > - xfs_aops_discard_page(page); > - ClearPageUptodate(page); > - unlock_page(page); > + set_page_writeback_keepwrite(page); > } else { > - /* > - * We can end up here with no error and nothing to write if we > - * race with a partial page truncate on a sub-page block sized > - * filesystem. In that case we need to mark the page clean. > - */ > clear_page_dirty_for_io(page); > set_page_writeback(page); > - unlock_page(page); > - end_page_writeback(page); > } > > + unlock_page(page); > + > + /* > + * Preserve the original error if there was one, otherwise catch > + * submission errors here and propagate into subsequent ioend > + * submissions. > + */ > + list_for_each_entry_safe(ioend, next, &submit_list, io_list) { > + int error2; > + > + list_del_init(&ioend->io_list); > + error2 = xfs_submit_ioend(wbc, ioend, error); > + if (error2 && !error) > + error = error2; > + } > + > + /* > + * We can end up here with no error and nothing to write if we race with > + * a partial page truncate on a sub-page block sized filesystem. > + */ > + if (!count) > + end_page_writeback(page); > +done: > mapping_set_error(page->mapping, error); > return error; > } > -- > 2.17.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html