From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id 5BD0A28024B for ; Sat, 24 Sep 2016 09:18:39 -0400 (EDT) Received: by mail-pf0-f200.google.com with SMTP id 21so281525757pfy.3 for ; Sat, 24 Sep 2016 06:18:39 -0700 (PDT) Received: from mail-pa0-x243.google.com (mail-pa0-x243.google.com. [2607:f8b0:400e:c03::243]) by mx.google.com with ESMTPS id p72si13606496pfi.197.2016.09.24.06.18.38 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 24 Sep 2016 06:18:38 -0700 (PDT) Received: by mail-pa0-x243.google.com with SMTP id my20so6324268pab.3 for ; Sat, 24 Sep 2016 06:18:38 -0700 (PDT) Subject: Re: [PATCH] mm: warn about allocations which stall for too long References: <20160923081555.14645-1-mhocko@kernel.org> <57E56789.1070205@intel.com> From: Balbir Singh Message-ID: <31729f1f-c0da-29e4-5777-69446daab122@gmail.com> Date: Sat, 24 Sep 2016 23:19:04 +1000 MIME-Version: 1.0 In-Reply-To: <57E56789.1070205@intel.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Dave Hansen , Michal Hocko , linux-mm@kvack.org Cc: Andrew Morton , Johannes Weiner , Mel Gorman , Tetsuo Handa , LKML , Michal Hocko On 24/09/16 03:34, Dave Hansen wrote: > On 09/23/2016 01:15 AM, Michal Hocko wrote: >> + /* Make sure we know about allocations which stall for too long */ >> + if (!(gfp_mask & __GFP_NOWARN) && time_after(jiffies, alloc_start + stall_timeout)) { >> + pr_warn("%s: page alloction stalls for %ums: order:%u mode:%#x(%pGg)\n", >> + current->comm, jiffies_to_msecs(jiffies-alloc_start), >> + order, gfp_mask, &gfp_mask); >> + stall_timeout += 10 * HZ; >> + dump_stack(); >> + } > > This would make an awesome tracepoint. There's probably still plenty of > value to having it in dmesg, but the configurability of tracepoints is > hard to beat. An awesome tracepoint and a great place to trigger other tracepoints. With stall timeout increasing every time, do we only care about the first instance when we exceeded stall_timeout? Do we debug just that instance? Balbir Singh. -- 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