From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id 5E4BF440846 for ; Thu, 24 Aug 2017 13:49:21 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id u20so597731pgb.10 for ; Thu, 24 Aug 2017 10:49:21 -0700 (PDT) Received: from mga01.intel.com (mga01.intel.com. [192.55.52.88]) by mx.google.com with ESMTPS id l23si3186479pgu.76.2017.08.24.10.49.19 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 24 Aug 2017 10:49:19 -0700 (PDT) Subject: Re: [PATCH 1/2] sched/wait: Break up long wake list walk References: <20170818185455.qol3st2nynfa47yc@techsingularity.net> <20170821183234.kzennaaw2zt2rbwz@techsingularity.net> <37D7C6CF3E00A74B8858931C1DB2F07753788B58@SHSMSX103.ccr.corp.intel.com> <37D7C6CF3E00A74B8858931C1DB2F0775378A24A@SHSMSX103.ccr.corp.intel.com> <37D7C6CF3E00A74B8858931C1DB2F0775378A377@SHSMSX103.ccr.corp.intel.com> <37D7C6CF3E00A74B8858931C1DB2F0775378A8AB@SHSMSX103.ccr.corp.intel.com> <6e8b81de-e985-9222-29c5-594c6849c351@linux.intel.com> From: Tim Chen Message-ID: <85fb2a78-cbb7-dceb-12e8-7d18519c30a0@linux.intel.com> Date: Thu, 24 Aug 2017 10:49:18 -0700 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Linus Torvalds Cc: "Liang, Kan" , Mel Gorman , Mel Gorman , "Kirill A. Shutemov" , Peter Zijlstra , Ingo Molnar , Andi Kleen , Andrew Morton , Johannes Weiner , Jan Kara , linux-mm , Linux Kernel Mailing List On 08/23/2017 04:30 PM, Linus Torvalds wrote: > On Wed, Aug 23, 2017 at 11:17 AM, Linus Torvalds > wrote: >> On Wed, Aug 23, 2017 at 8:58 AM, Tim Chen wrote: >>> >>> Will you still consider the original patch as a fail safe mechanism? >> >> I don't think we have much choice, although I would *really* want to >> get this root-caused rather than just papering over the symptoms. > > Oh well. Apparently we're not making progress on that, so I looked at > the patch again. > > Can we fix it up a bit? In particular, the "bookmark_wake_function()" > thing added no value, and definitely shouldn't have been exported. > Just use NULL instead. > > And the WAITQUEUE_WALK_BREAK_CNT thing should be internal to > __wake_up_common(), not in some common header file. Again, there's no > value in exporting it to anybody else. > > And doing > > if (curr->flags & WQ_FLAG_BOOKMARK) > > looks odd, when we just did > > unsigned flags = curr->flags; > > one line earlier, so that can be just simplified. > > So can you test that simplified version of the patch? I'm attaching my > suggested edited patch, but you may just want to do those changes > directly to your tree instead. These changes look fine. We are testing them now. Does the second patch in the series look okay to you? Thanks. Tim -- 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