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[209.132.180.67]) by mx.google.com with ESMTP id v5si10965343pgh.510.2018.12.17.05.13.46; Mon, 17 Dec 2018 05:14:01 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=ZLOofSpH; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727568AbeLQNM5 (ORCPT + 99 others); Mon, 17 Dec 2018 08:12:57 -0500 Received: from mail-yb1-f173.google.com ([209.85.219.173]:35524 "EHLO mail-yb1-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727108AbeLQNM5 (ORCPT ); Mon, 17 Dec 2018 08:12:57 -0500 Received: by mail-yb1-f173.google.com with SMTP id z2-v6so5043390ybj.2 for ; Mon, 17 Dec 2018 05:12:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=QOfplFds6EIUWOBhy40nhRvyfIR9Xhr39hZz8BRtwOQ=; b=ZLOofSpHfhN/niqagytI+agUhxA3+kyXhVg2F6NjasXE92Q8FfZGNUR/iv1LmBeIxe 6RVGkVCyh7Nv5Ate6LbMf/5gzQzld1WgIwUE3wM2WNBH5F8r9/xO72hcF+Sx2MH6F3SD RG9ocFMbDRlzeP1K/TIfVTNHr7FtHkGlyljAaW7kU3Zu9zdg8x4Q3Q9Ssnb44a2YPaNp Cl6moyxkNVp+kfyjcngL7OAUh5uDXrHmbBhuq60nA/8ZxkzW6rrDYGQce/hUEfnXh9ET CD93aPLQbeMQ6FKl16aAhKG7+Uyw2GZ+RsmjVVBpgHMASnktB1oLazI9CI893SN+FAAf KNHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=QOfplFds6EIUWOBhy40nhRvyfIR9Xhr39hZz8BRtwOQ=; b=A24DRrGi8IPrnIFVNpjRIfGWFD2P96tyQOxeadi9igYSxHvlmHLV/1GGb3wuzlXhR2 DIcAt+rRJQpdG4+EZP2yptokntXLhSE+bN3a49XG4lB+7CEe0epwwYNvjFHDw8tJAf4J CaaJZT0vqguTCfgM89izhnRpJrx7hO3m78pqLs7IM6fUJw7+WD4Dxa/D/dQ3cBgcY4yh Vqq9FZXBzHE9FRuhNVxS9AzWWUh3Vha9ryfECrZs3L56DaBl9du2Hp8Qo1cF4sdVza+M aWnzsX8EUxbz7MNKq/IxX4FoGGxlXCXclepa7jcbnmaEQH3Qn17/O9WnVCjxkSQP2Wm/ YuUw== X-Gm-Message-State: AA+aEWbhk8Azy7tlGZMLDe9DqlX6G4GMYtobCwf0zpYcrPfveEB0VEGd J4Ep5g8LcXLBkEGHSjVYZrTgNaQAqiNYH8FHvic= X-Received: by 2002:a25:e404:: with SMTP id b4mr13021985ybh.517.1545052376013; Mon, 17 Dec 2018 05:12:56 -0800 (PST) MIME-Version: 1.0 References: <5598cd71-c3c8-d6ef-eb30-777cf901a2ef@redhat.com> <20181129160627.GU2131@hirez.programming.kicks-ass.net> <8cc45695-b325-a219-8b46-d5da6ddfdd63@redhat.com> <20181129172700.GA11632@hirez.programming.kicks-ass.net> <20181129180828.GA11650@hirez.programming.kicks-ass.net> <729ceddb-dd9a-ec2a-f74e-03fa4d7e65e8@redhat.com> <20181129213017.v3eljor54lfpoug2@linux-r8p5> <20181129213421.wwvhsjql3m3lvtv4@linux-r8p5> <20181129221714.GF11632@hirez.programming.kicks-ass.net> <20181217113718.GB4900@worktop.programming.kicks-ass.net> In-Reply-To: <20181217113718.GB4900@worktop.programming.kicks-ass.net> From: Yongji Xie Date: Mon, 17 Dec 2018 21:12:44 +0800 Message-ID: Subject: Re: [RFC] locking/rwsem: Avoid issuing wakeup before setting the reader waiter to nil To: peterz@infradead.org Cc: dave@stgolabs.net, mingo@redhat.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, Xie Yongji , zhangyu31@baidu.com, liuqi16@baidu.com, yuanlinsi01@baidu.com, nixun@baidu.com, lilin24@baidu.com, longman@redhat.com, andrea.parri@amarulasolutions.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 17 Dec 2018 at 19:37, Peter Zijlstra wrote: > > On Mon, Dec 10, 2018 at 11:12:52PM +0800, Yongji Xie wrote: > > Hi Peter, > > > > Please let me know If there is any progress on this issue. Thank you! > > Right, sorry, my brain was filled with snot and didn't want to make > sense of things. > > I've put some patches here: > > git://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git locking/core > > Could you have a look? That looks good to me. Thank you! Thanks, Yongji