From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EAA7976049 for ; Mon, 29 Jan 2024 20:12:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706559157; cv=none; b=b0VyEdSdPH1WNE5BqNzIUDnhX2OJrgyEITC9yawDsk/Q7PZYize6B/Go4ayn5BbOXg3SigCehdt5RROIpcJ6CQHhf59fXm5aVNOi6b+LUMNukJHi7yLL/ATJVG8MqqFp9ECCaOVgc5LXKcUAlLhvqoEe94hXqzUSdLXrRpIytoE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706559157; c=relaxed/simple; bh=WCbvnW9dMahO0e4Ry6XopkLNjudSEdxv5YHLtY1umvg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=AFrb7DMYOwV8v6TRxQNZyvEzHV8bUP1jV55/1w5lijW7UstJkmxkWd+x8Bgv9iL6/wDRjZppVczbbgFJqHRBBUK5az4GJn7fvyAvdxCiCoItTxKTXW6gqBQqef/NBx9JxrzNY1kN5lTGemi092bwaMXBXAERiYhoFzXwJuXaFfg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Ga8gFpp7; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Ga8gFpp7" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1706559154; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=qK9tbpAJWU+jCclBGn+oKppMC1R8LcdvjWspqD2gVlo=; b=Ga8gFpp7da5k/FfCqMRhX1cfF31mb6V5VWFZETxzxPwzPxETN2MfELKOFN+AjT9QUcyuGH ebVm7nGBKAKuVQrm89bEJt4iuD/Ou99ag5KEKO/fw2fCCophYrjKM+TIzkL739amCUAIWt CCpRMCH16xvxxonxg8zlZzNwgJBnPCo= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-215-J6DXV2dePT6btmWl161NIw-1; Mon, 29 Jan 2024 15:12:30 -0500 X-MC-Unique: J6DXV2dePT6btmWl161NIw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 727D4837224; Mon, 29 Jan 2024 20:12:29 +0000 (UTC) Received: from bfoster (unknown [10.22.32.186]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E6433AD4; Mon, 29 Jan 2024 20:12:28 +0000 (UTC) Date: Mon, 29 Jan 2024 15:13:47 -0500 From: Brian Foster To: Christoph Hellwig Cc: linux-mm@kvack.org, Matthew Wilcox , Jan Kara , David Howells , Christian Brauner , "Darrick J. Wong" , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Jan Kara , Dave Chinner Subject: Re: [PATCH 06/19] writeback: Factor out writeback_finish() Message-ID: References: <20240125085758.2393327-1-hch@lst.de> <20240125085758.2393327-7-hch@lst.de> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240125085758.2393327-7-hch@lst.de> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.1 On Thu, Jan 25, 2024 at 09:57:45AM +0100, Christoph Hellwig wrote: > From: "Matthew Wilcox (Oracle)" > > Instead of having a 'done' variable that controls the nested loops, > have a writeback_finish() that can be returned directly. This involves > keeping more things in writeback_control, but it's just moving stuff > allocated on the stack to being allocated slightly earlier on the stack. > > Signed-off-by: Matthew Wilcox (Oracle) > [hch: heavily rebased, reordered and commented struct writeback_control] > Signed-off-by: Christoph Hellwig > Reviewed-by: Jan Kara > Acked-by: Dave Chinner > --- > include/linux/writeback.h | 6 +++ > mm/page-writeback.c | 79 ++++++++++++++++++++------------------- > 2 files changed, 47 insertions(+), 38 deletions(-) > ... > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index 437745a511c634..fcd90a176d806c 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c ... > @@ -2419,22 +2437,23 @@ int write_cache_pages(struct address_space *mapping, > } else { > tag = PAGECACHE_TAG_DIRTY; > } > - done_index = index; > - while (!done && (index <= end)) { > + > + folio_batch_init(&wbc->fbatch); > + wbc->err = 0; > + > + while (index <= end) { > int i; > > nr_folios = filemap_get_folios_tag(mapping, &index, end, > - tag, &fbatch); > + tag, &wbc->fbatch); > > if (nr_folios == 0) > break; > > for (i = 0; i < nr_folios; i++) { > - struct folio *folio = fbatch.folios[i]; > + struct folio *folio = wbc->fbatch.folios[i]; > unsigned long nr; > > - done_index = folio->index; > - > folio_lock(folio); > > /* > @@ -2481,6 +2500,9 @@ int write_cache_pages(struct address_space *mapping, > folio_unlock(folio); > error = 0; > } > + JFYI: whitespace damage on the above line. > + if (error && !wbc->err) > + wbc->err = error; > Also what happened to the return of the above "first error encountered" for the WB_SYNC_ALL case? Is that not needed for some reason (and so the comment just below might require an update)? Brian > /* > * For integrity sync we have to keep going until we > @@ -2496,38 +2518,19 @@ int write_cache_pages(struct address_space *mapping, > * off and media errors won't choke writeout for the > * entire file. > */ > - if (error && !ret) > - ret = error; > - if (wbc->sync_mode == WB_SYNC_NONE) { > - if (ret || wbc->nr_to_write <= 0) { > - done_index = folio->index + nr; > - done = 1; > - break; > - } > + if (wbc->sync_mode == WB_SYNC_NONE && > + (wbc->err || wbc->nr_to_write <= 0)) { > + writeback_finish(mapping, wbc, > + folio->index + nr); > + return error; > } > } > - folio_batch_release(&fbatch); > + folio_batch_release(&wbc->fbatch); > cond_resched(); > } > > - /* > - * For range cyclic writeback we need to remember where we stopped so > - * that we can continue there next time we are called. If we hit the > - * last page and there is more work to be done, wrap back to the start > - * of the file. > - * > - * For non-cyclic writeback we always start looking up at the beginning > - * of the file if we are called again, which can only happen due to > - * -ENOMEM from the file system. > - */ > - if (wbc->range_cyclic) { > - if (done) > - mapping->writeback_index = done_index; > - else > - mapping->writeback_index = 0; > - } > - > - return ret; > + writeback_finish(mapping, wbc, 0); > + return 0; > } > EXPORT_SYMBOL(write_cache_pages); > > -- > 2.39.2 > >