From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f70.google.com (mail-wm0-f70.google.com [74.125.82.70]) by kanga.kvack.org (Postfix) with ESMTP id 759936B0260 for ; Wed, 20 Sep 2017 11:36:29 -0400 (EDT) Received: by mail-wm0-f70.google.com with SMTP id r74so3192574wme.5 for ; Wed, 20 Sep 2017 08:36:29 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id i53si2038173eda.1.2017.09.20.08.36.28 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 20 Sep 2017 08:36:28 -0700 (PDT) Date: Wed, 20 Sep 2017 17:36:27 +0200 From: Jan Kara Subject: Re: [PATCH 5/6] fs-writeback: move nr_pages == 0 logic to one location Message-ID: <20170920153627.GI11106@quack2.suse.cz> References: <1505850787-18311-1-git-send-email-axboe@kernel.dk> <1505850787-18311-6-git-send-email-axboe@kernel.dk> <20170920144159.GF11106@quack2.suse.cz> <33ba51dc-cb93-ad8c-d973-41ac12cb9e90@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <33ba51dc-cb93-ad8c-d973-41ac12cb9e90@kernel.dk> Sender: owner-linux-mm@kvack.org List-ID: To: Jens Axboe Cc: Jan Kara , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, hannes@cmpxchg.org, clm@fb.com On Wed 20-09-17 09:05:51, Jens Axboe wrote: > On 09/20/2017 08:41 AM, Jan Kara wrote: > > On Tue 19-09-17 13:53:06, Jens Axboe wrote: > >> Now that we have no external callers of wb_start_writeback(), > >> we can move the nr_pages == 0 logic into that function. > >> > >> Signed-off-by: Jens Axboe > > > > ... > > > >> +static unsigned long get_nr_dirty_pages(void) > >> +{ > >> + return global_node_page_state(NR_FILE_DIRTY) + > >> + global_node_page_state(NR_UNSTABLE_NFS) + > >> + get_nr_dirty_inodes(); > >> +} > >> + > >> static void wb_start_writeback(struct bdi_writeback *wb, long nr_pages, > >> bool range_cyclic, enum wb_reason reason) > >> { > >> @@ -942,6 +953,12 @@ static void wb_start_writeback(struct bdi_writeback *wb, long nr_pages, > >> return; > >> > >> /* > >> + * If someone asked for zero pages, we write out the WORLD > >> + */ > >> + if (!nr_pages) > >> + nr_pages = get_nr_dirty_pages(); > >> + > > > > So for 'wb' we have a better estimate of the amount we should write - use > > wb_stat_sum(wb, WB_RECLAIMABLE) statistics - that is essentially dirty + > > unstable_nfs broken down to bdi_writeback. > > I don't mind making that change, but I think that should be a separate > patch. We're using get_nr_dirty_pages() in existing locations where > we have the 'wb', like in wb_check_old_data_flush(). Good point and fully agreed. So you can add: Reviewed-by: Jan Kara for this patch. Honza -- Jan Kara SUSE Labs, CR -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org