From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f197.google.com (mail-io0-f197.google.com [209.85.223.197]) by kanga.kvack.org (Postfix) with ESMTP id 48B836B0279 for ; Sun, 28 May 2017 03:01:08 -0400 (EDT) Received: by mail-io0-f197.google.com with SMTP id l78so26430868iod.4 for ; Sun, 28 May 2017 00:01:08 -0700 (PDT) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [2001:e42:101:1:202:181:97:72]) by mx.google.com with ESMTPS id o3si7281083ite.25.2017.05.28.00.01.06 for (version=TLS1 cipher=AES128-SHA bits=128/128); Sun, 28 May 2017 00:01:07 -0700 (PDT) Subject: Re: [PATCH v9] mm: Add memory allocation watchdog kernel thread. From: Tetsuo Handa References: <1495331504-12480-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> In-Reply-To: <1495331504-12480-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> Message-Id: <201705281601.BBE81220.HFLOtSFFOJVQMO@I-love.SAKURA.ne.jp> Date: Sun, 28 May 2017 16:01:02 +0900 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Tetsuo Handa wrote: > Changes from v7 [11]: > > (1) Reflect review comments from Andrew Morton. (Convert "u8 type" to > "bool report", use CPUHP_PAGE_ALLOC_DEAD event and replace > for_each_possible_cpu() with for_each_online_cpu(), reuse existing > rcu_lock_break() and hung_timeout_jiffies() for now, update comments). > > Changes from v8 [12]: > > (1) Check mempool_alloc() as well, for mempool_alloc() is a sort of > open-coded __GFP_NOFAIL allocation request where warn_alloc() cannot > detect stalls due to __GFP_NORETRY, and actually I found a case where > kswapd was unable to get memory for bio from mempool at > bio_alloc_bioset(GFP_NOFS) [13], and I believe there are similar bugs. Andrew, I believe it is time to start testing at linux-next. Nobody shows interests in detecting/analyzing OOM livelock but there are still unsolved suspicious cases http://lkml.kernel.org/r/da13c3c7-b514-67b0-2eb9-6d6af277901b@wiesinger.com http://lkml.kernel.org/r/20170502141544.rufykv6blliqzqfd@merlins.org http://lkml.kernel.org/r/CAM_iQpWuPVGc2ky8M-9yukECtS+zKjiDasNymX7rMcBjBFyM_A@mail.gmail.com where this patch might have given some clues if this patch were available. There is no reason not to allow users to try this debugging aid. -- 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