From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754402Ab1G0OYL (ORCPT ); Wed, 27 Jul 2011 10:24:11 -0400 Received: from cantor2.suse.de ([195.135.220.15]:57544 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754265Ab1G0OYI (ORCPT ); Wed, 27 Jul 2011 10:24:08 -0400 Date: Wed, 27 Jul 2011 16:24:05 +0200 From: Michal Hocko To: Johannes Weiner Cc: linux-mm@kvack.org, Dave Chinner , Christoph Hellwig , Mel Gorman , Andrew Morton , Wu Fengguang , Rik van Riel , Minchan Kim , Jan Kara , Andi Kleen , linux-kernel@vger.kernel.org Subject: Re: [patch 4/5] mm: writeback: throttle __GFP_WRITE on per-zone dirty limits Message-ID: <20110727142405.GG4024@tiehlicka.suse.cz> References: <1311625159-13771-1-git-send-email-jweiner@redhat.com> <1311625159-13771-5-git-send-email-jweiner@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1311625159-13771-5-git-send-email-jweiner@redhat.com> 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 On Mon 25-07-11 22:19:18, Johannes Weiner wrote: [...] > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index 41dc871..ce673ec 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -378,6 +390,24 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned max_ratio) > } > EXPORT_SYMBOL(bdi_set_max_ratio); > > +static void sanitize_dirty_limits(unsigned long *pbackground, > + unsigned long *pdirty) > +{ > + unsigned long background = *pbackground; > + unsigned long dirty = *pdirty; > + struct task_struct *tsk; > + > + if (background >= dirty) > + background = dirty / 2; > + tsk = current; > + if (tsk->flags & PF_LESS_THROTTLE || rt_task(tsk)) { > + background += background / 4; > + dirty += dirty / 4; > + } > + *pbackground = background; > + *pdirty = dirty; > +} > + > /* > * global_dirty_limits - background-writeback and dirty-throttling thresholds > * > @@ -389,33 +419,52 @@ EXPORT_SYMBOL(bdi_set_max_ratio); > */ > void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty) > { > - unsigned long background; > - unsigned long dirty; > unsigned long uninitialized_var(available_memory); > - struct task_struct *tsk; > > if (!vm_dirty_bytes || !dirty_background_bytes) > available_memory = determine_dirtyable_memory(); > > if (vm_dirty_bytes) > - dirty = DIV_ROUND_UP(vm_dirty_bytes, PAGE_SIZE); > + *pdirty = DIV_ROUND_UP(vm_dirty_bytes, PAGE_SIZE); > else > - dirty = (vm_dirty_ratio * available_memory) / 100; > + *pdirty = vm_dirty_ratio * available_memory / 100; > > if (dirty_background_bytes) > - background = DIV_ROUND_UP(dirty_background_bytes, PAGE_SIZE); > + *pbackground = DIV_ROUND_UP(dirty_background_bytes, PAGE_SIZE); > else > - background = (dirty_background_ratio * available_memory) / 100; > + *pbackground = dirty_background_ratio * available_memory / 100; > > - if (background >= dirty) > - background = dirty / 2; > - tsk = current; > - if (tsk->flags & PF_LESS_THROTTLE || rt_task(tsk)) { > - background += background / 4; > - dirty += dirty / 4; > - } > - *pbackground = background; > - *pdirty = dirty; > + sanitize_dirty_limits(pbackground, pdirty); > +} Hmm, wouldn't be the patch little bit easier to read if this was outside in a separate (cleanup) one? -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic