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[23.128.96.18]) by mx.google.com with ESMTP id hk12si8153477ejb.174.2021.09.20.20.41.25; Mon, 20 Sep 2021 20:41:48 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=STnz18zc; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235006AbhITV5v (ORCPT + 99 others); Mon, 20 Sep 2021 17:57:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:40758 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229710AbhITVzu (ORCPT ); Mon, 20 Sep 2021 17:55:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1632174863; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=9UIsylLPvYShfxauOf8jQZM0FMZ6CBRqo/Eg9Bevgk8=; b=STnz18zcmrz3TOsPsa7QvlT5KpM1BYPJ05DGH2Pe6yOuVVM6hGxEUAnD3EE4K04Wovw4QU Qs0IJ4CfwxuHBPQJRicezsFuq8CHx4pMwED2luOkl4t/VeRsmdt6DcJG0ltq2YIScstxQO UbMwGyNUI5E1Wn1kOYpjYjaNaSzvidg= Received: from mail-qv1-f70.google.com (mail-qv1-f70.google.com [209.85.219.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-447-ykhd0x3FMByF_q4ZRL9MLA-1; Mon, 20 Sep 2021 17:54:22 -0400 X-MC-Unique: ykhd0x3FMByF_q4ZRL9MLA-1 Received: by mail-qv1-f70.google.com with SMTP id h25-20020a0cab19000000b0037a49d15c93so199270325qvb.22 for ; Mon, 20 Sep 2021 14:54:22 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:subject:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=9UIsylLPvYShfxauOf8jQZM0FMZ6CBRqo/Eg9Bevgk8=; b=2BZ8S0NmqUdVZek52VJtXPjfsB+NC26XOsCY7cY++/jtiB1cTK+1fXkg46TFo1/7xl 0oFrTtLJEYs84HMtph8q86d3VpR+VuZgmPPNKvouKU0FX6Di+6q5CUap5zRxkhxEaMoG bURF8hNFs81LP0AE0GsGkcnyhpmA98pMBE95XI10Qt4duwYxVDNirJLLJm0L2Ru/D+vt qJsjHeKIpCvLJspAuACZfeFHxtTzhKuf74YNmxyKuLYuJaGjw9cEJssmqwoPcSO7lG3L VQ2aoGnEMEaUfVZDtY2BHhrRWcJZAea0H123WbURVfH5awhqATOPhMZzqUwTa2ejhBp/ eO6g== X-Gm-Message-State: AOAM5315IOn9iWzPWfhpSXadqzShEzE3U02o5ZASGtLzsgYJRjlV/nlf 2h9j0gz5hWIIwrsdjgf3U0pFWOlPlgDBzzOxTzFMuFU5CZjOv42enMleWlGBFiTfWXRM/CtZwUy 2B2Dx6wMLteYBeiz9Weo5jxk22lHpiL8rWa2+NitXSWMRVnNigosG5xHE8PzHO9YXKhf6PHxV X-Received: by 2002:ac8:59d6:: with SMTP id f22mr24742057qtf.405.1632174861204; Mon, 20 Sep 2021 14:54:21 -0700 (PDT) X-Received: by 2002:ac8:59d6:: with SMTP id f22mr24742028qtf.405.1632174860852; Mon, 20 Sep 2021 14:54:20 -0700 (PDT) Received: from llong.remote.csb ([2601:191:8500:76c0::cdbc]) by smtp.gmail.com with ESMTPSA id l13sm2416172qkj.130.2021.09.20.14.54.19 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Sep 2021 14:54:20 -0700 (PDT) From: Waiman Long X-Google-Original-From: Waiman Long Subject: Re: [PATCH -tip 0/2] locking/rwbase: Two reader optimizations To: Davidlohr Bueso , tglx@linutronix.de Cc: peterz@infradead.org, mingo@kernel.org, rostedt@goodmis.org, bigeasy@linutronix.de, boqun.feng@gmail.com, linux-kernel@vger.kernel.org References: <20210920052031.54220-1-dave@stgolabs.net> Message-ID: <1676b749-3fca-fa67-03e6-7639ef1f5b33@redhat.com> Date: Mon, 20 Sep 2021 17:54:19 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210920052031.54220-1-dave@stgolabs.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/20/21 1:20 AM, Davidlohr Bueso wrote: > Hi, > > Patch 1 is a barrier optimization that came up from the reader > fastpath ordering auditing. > > Patch 2 is a resend of the previous broken patch that attempts > to use wake_q for read_unlock() slowpath. > > Tested on v5.15.y-rt. Applies against tip/urgent. > > Thanks! > > Davidlohr Bueso (2): > locking/rwbase: Optimize rwbase_read_trylock > locking/rwbase: Lockless reader waking up a writer > > kernel/locking/rtmutex.c | 19 +++++++++++++------ > kernel/locking/rwbase_rt.c | 11 +++++++---- > 2 files changed, 20 insertions(+), 10 deletions(-) > > -- > 2.26.2 > Your patches look good to me. Acked-by: Waiman Long