Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752854AbbGNXoa (ORCPT ); Tue, 14 Jul 2015 19:44:30 -0400 Received: from mail-ig0-f178.google.com ([209.85.213.178]:33980 "EHLO mail-ig0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751746AbbGNXo3 (ORCPT ); Tue, 14 Jul 2015 19:44:29 -0400 Date: Tue, 14 Jul 2015 16:44:27 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Andrew Morton cc: Sergey Senozhatsky , Michal Hocko , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [patch v3 1/3] mm, oom: organize oom context into struct In-Reply-To: <20150714155251.ddb7ef5a54b3b1f49d5fc968@linux-foundation.org> Message-ID: References: <20150714155251.ddb7ef5a54b3b1f49d5fc968@linux-foundation.org> User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1700 Lines: 51 On Tue, 14 Jul 2015, Andrew Morton wrote: > > --- a/include/linux/oom.h > > +++ b/include/linux/oom.h > > @@ -12,6 +12,14 @@ struct notifier_block; > > struct mem_cgroup; > > struct task_struct; > > > > +struct oom_control { > > + struct zonelist *zonelist; > > + nodemask_t *nodemask; > > + gfp_t gfp_mask; > > + int order; > > + bool force_kill; > > +}; > > Some docs would be nice. > Ok! > gfp_mask and order are what the page-allocating caller originally asked > for, I think? They haven't been mucked with? > Yes, it's a good opportunity to make them const. > It's somewhat obvious what force_kill does, but why is it provided, why > is it set? And what does it actually kill? A process which was > selected based on the other fields... > It's removed in the next patch since it's unneeded, so I'll define what order == -1 means. > Also, it's a bit odd that zonelist and nodemask are here. They're > low-level implementation details whereas the other three fields are > high-level caller control stuff. > Zonelist and nodemask are indeed pretty weird here. We use them to determine if the oom kill is constrained by cpuset and/or mempolicy, respectively so we don't kill things unnecessarily and leave a cpuset still oom, for example. We could determine that before actually calling the oom killer and passing the enum oom_constraint in, but its purpose is for the oom killer so it's just a part of that logical unit. -- 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/