From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753197AbdKIQ1i (ORCPT ); Thu, 9 Nov 2017 11:27:38 -0500 Received: from smtprelay0212.hostedemail.com ([216.40.44.212]:54958 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751020AbdKIQ1g (ORCPT ); Thu, 9 Nov 2017 11:27:36 -0500 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,joe@perches.com,:::::,RULES_HIT:41:355:379:541:599:973:988:989:1260:1277:1311:1313:1314:1345:1359:1373:1437:1515:1516:1518:1534:1541:1593:1594:1711:1730:1747:1777:1792:2198:2199:2393:2559:2562:2731:2828:3138:3139:3140:3141:3142:3353:3622:3865:3866:3867:3868:3871:3873:4250:4321:5007:6119:9545:10004:10400:10848:11026:11232:11658:11914:12043:12296:12679:12740:12760:12895:13069:13311:13357:13439:14181:14659:14721:21080:21451:21627:30054:30056:30091,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:2,LUA_SUMMARY:none X-HE-Tag: card62_7c63109e30631 X-Filterd-Recvd-Size: 2915 Message-ID: <1510244853.15768.64.camel@perches.com> Subject: Re: [PATCH] mm/page_alloc: Avoid KERN_CONT uses in warn_alloc From: Joe Perches To: Michal Hocko Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org Date: Thu, 09 Nov 2017 08:27:33 -0800 In-Reply-To: <20171109100531.3cn2hcqnuj7mjaju@dhcp22.suse.cz> References: <20171107125055.cl5pyp2zwon44x5l@dhcp22.suse.cz> <1510068865.1000.19.camel@perches.com> <20171107154351.ebtitvjyo5v3bt26@dhcp22.suse.cz> <1510070607.1000.23.camel@perches.com> <20171109100531.3cn2hcqnuj7mjaju@dhcp22.suse.cz> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.26.1-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2017-11-09 at 11:05 +0100, Michal Hocko wrote: [] > Subject: [PATCH] mm: simplify nodemask printing > > alloc_warn and dump_header have to explicitly handle NULL nodemask which > forces both paths to use pr_cont. We can do better. printk already > handles NULL pointers properly so all what we need is to teach > nodemask_pr_args to handle NULL nodemask carefully. This allows > simplification of both alloc_warn and dump_header and get rid of pr_cont > altogether. [] > diff --git a/mm/oom_kill.c b/mm/oom_kill.c [] > @@ -426,14 +426,10 @@ static void dump_tasks(struct mem_cgroup *memcg, const nodemask_t *nodemask) > > static void dump_header(struct oom_control *oc, struct task_struct *p) > { > - pr_warn("%s invoked oom-killer: gfp_mask=%#x(%pGg), nodemask=", > - current->comm, oc->gfp_mask, &oc->gfp_mask); > - if (oc->nodemask) > - pr_cont("%*pbl", nodemask_pr_args(oc->nodemask)); > - else > - pr_cont("(null)"); > - pr_cont(", order=%d, oom_score_adj=%hd\n", > - oc->order, current->signal->oom_score_adj); > + pr_warn("%s invoked oom-killer: gfp_mask=%#x(%pGg), nodemask=%*pbl, order=%d, oom_score_adj=%hd\n", > + current->comm, oc->gfp_mask, &oc->gfp_mask, > + nodemask_pr_args(oc->nodemask), oc->order, > + current->signal->oom_score_adj); trivia: You could align the arguments to the open parenthesis here > diff --git a/mm/page_alloc.c b/mm/page_alloc.c [] > @@ -3281,20 +3281,14 @@ void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...) > if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs)) > return; > > - pr_warn("%s: ", current->comm); > - > va_start(args, fmt); > vaf.fmt = fmt; > vaf.va = &args; > - pr_cont("%pV", &vaf); > + pr_warn("%s: %pV, mode:%#x(%pGg), nodemask=%*pbl\n", > + current->comm, &vaf, gfp_mask, &gfp_mask, > + nodemask_pr_args(nodemask)); and here