Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752744Ab3GIRHG (ORCPT ); Tue, 9 Jul 2013 13:07:06 -0400 Received: from cantor2.suse.de ([195.135.220.15]:52001 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751749Ab3GIRHA (ORCPT ); Tue, 9 Jul 2013 13:07:00 -0400 Date: Tue, 9 Jul 2013 19:06:56 +0200 From: Jan Kara To: Maxim Patlasov Cc: akpm@linux-foundation.org, riel@redhat.com, jack@suse.cz, dev@parallels.com, miklos@szeredi.hu, fuse-devel@lists.sourceforge.net, bfoster@redhat.com, xemul@parallels.com, linux-kernel@vger.kernel.org, jbottomley@parallels.com, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, fengguang.wu@intel.com, devel@openvz.org, mgorman@suse.de Subject: Re: [PATCH] mm: cleanup backing_dev_info foo_stamp fields Message-ID: <20130709170656.GB7256@quack.suse.cz> References: <20130705155018.3532.45042.stgit@maximpc.sw.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130705155018.3532.45042.stgit@maximpc.sw.ru> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3444 Lines: 90 On Fri 05-07-13 19:50:41, Maxim Patlasov wrote: > State clearly that bw_time_stamp is measured in jiffies. Rename other > foo_stamp fields to reflect that they are in units of number-of-pages. > > Reported-by: Andrew Morton > Signed-off-by: Maxim Patlasov Looks good. You can add: Reviewed-by: Jan Kara Honza > --- > include/linux/backing-dev.h | 7 ++++--- > mm/backing-dev.c | 2 +- > mm/page-writeback.c | 8 ++++---- > 3 files changed, 9 insertions(+), 8 deletions(-) > > diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h > index c388155..ee7eb1a 100644 > --- a/include/linux/backing-dev.h > +++ b/include/linux/backing-dev.h > @@ -73,9 +73,10 @@ struct backing_dev_info { > > struct percpu_counter bdi_stat[NR_BDI_STAT_ITEMS]; > > - unsigned long bw_time_stamp; /* last time write bw is updated */ > - unsigned long dirtied_stamp; > - unsigned long written_stamp; /* pages written at bw_time_stamp */ > + unsigned long bw_time_stamp; /* last time (in jiffies) write bw > + * is updated */ > + unsigned long dirtied_nr_stamp; > + unsigned long written_nr_stamp; /* pages written at bw_time_stamp */ > unsigned long write_bandwidth; /* the estimated write bandwidth */ > unsigned long avg_write_bandwidth; /* further smoothed write bw */ > > diff --git a/mm/backing-dev.c b/mm/backing-dev.c > index 5025174..82efe7f 100644 > --- a/mm/backing-dev.c > +++ b/mm/backing-dev.c > @@ -454,7 +454,7 @@ int bdi_init(struct backing_dev_info *bdi) > bdi->dirty_exceeded = 0; > > bdi->bw_time_stamp = jiffies; > - bdi->written_stamp = 0; > + bdi->written_nr_stamp = 0; > > bdi->balanced_dirty_ratelimit = INIT_BW; > bdi->dirty_ratelimit = INIT_BW; > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index 4514ad7..088a8db 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -799,7 +799,7 @@ static void bdi_update_write_bandwidth(struct backing_dev_info *bdi, > * write_bandwidth = --------------------------------------------------- > * period > */ > - bw = written - bdi->written_stamp; > + bw = written - bdi->written_nr_stamp; > bw *= HZ; > if (unlikely(elapsed > period)) { > do_div(bw, elapsed); > @@ -910,7 +910,7 @@ static void bdi_update_dirty_ratelimit(struct backing_dev_info *bdi, > * The dirty rate will match the writeout rate in long term, except > * when dirty pages are truncated by userspace or re-dirtied by FS. > */ > - dirty_rate = (dirtied - bdi->dirtied_stamp) * HZ / elapsed; > + dirty_rate = (dirtied - bdi->dirtied_nr_stamp) * HZ / elapsed; > > pos_ratio = bdi_position_ratio(bdi, thresh, bg_thresh, dirty, > bdi_thresh, bdi_dirty); > @@ -1066,8 +1066,8 @@ void __bdi_update_bandwidth(struct backing_dev_info *bdi, > bdi_update_write_bandwidth(bdi, elapsed, written); > > snapshot: > - bdi->dirtied_stamp = dirtied; > - bdi->written_stamp = written; > + bdi->dirtied_nr_stamp = dirtied; > + bdi->written_nr_stamp = written; > bdi->bw_time_stamp = now; > } > > -- Jan Kara SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/