Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751641AbdITOfI (ORCPT ); Wed, 20 Sep 2017 10:35:08 -0400 Received: from mx2.suse.de ([195.135.220.15]:52211 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751463AbdITOfH (ORCPT ); Wed, 20 Sep 2017 10:35:07 -0400 Date: Wed, 20 Sep 2017 16:35:05 +0200 From: Jan Kara To: Jens Axboe Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, hannes@cmpxchg.org, clm@fb.com, jack@suse.cz Subject: Re: [PATCH 3/6] page-writeback: pass in '0' for nr_pages writeback in laptop mode Message-ID: <20170920143505.GD11106@quack2.suse.cz> References: <1505850787-18311-1-git-send-email-axboe@kernel.dk> <1505850787-18311-4-git-send-email-axboe@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1505850787-18311-4-git-send-email-axboe@kernel.dk> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 990 Lines: 30 On Tue 19-09-17 13:53:04, Jens Axboe wrote: > Laptop mode really wants to writeback the number of dirty > pages and inodes. Instead of calculating this in the caller, > just pass in 0 and let wakeup_flusher_threads() handle it. > > Use the new wakeup_flusher_threads_bdi() instead of rolling > our own. > > Signed-off-by: Jens Axboe ... > - rcu_read_lock(); > - list_for_each_entry_rcu(wb, &q->backing_dev_info->wb_list, bdi_node) > - if (wb_has_dirty_io(wb)) > - wb_start_writeback(wb, nr_pages, true, > - WB_REASON_LAPTOP_TIMER); > - rcu_read_unlock(); > + wakeup_flusher_threads_bdi(q->backing_dev_info, 0, > + WB_REASON_LAPTOP_TIMER); > } So this slightly changes the semantics since previously we were doing range_cyclic writeback and now we don't. I don't think this matters in practice but please mention that in the changelog. With that you can add: Reviewed-by: Jan Kara Honza -- Jan Kara SUSE Labs, CR