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([2601:188:c100:5710:315f:57b3:b997:5fca]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-46e102fc639sm67265221cf.25.2025.01.22.10.23.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 22 Jan 2025 10:23:12 -0800 (PST) From: Waiman Long X-Google-Original-From: Waiman Long Message-ID: <1049309f-cb3d-4d18-8a4a-96821605c389@redhat.com> Date: Wed, 22 Jan 2025 13:23:11 -0500 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] locking/semaphore: Use wake_q to wake up processes outside lock critical section To: Peter Zijlstra , Waiman Long Cc: Ingo Molnar , Will Deacon , Boqun Feng , linux-kernel@vger.kernel.org References: <20250122011314.2869715-1-longman@redhat.com> <20250122103914.GI7145@noisy.programming.kicks-ass.net> <414a685b-5a30-4792-b01d-35e8099d965b@redhat.com> <20250122181659.GB34562@noisy.programming.kicks-ass.net> Content-Language: en-US In-Reply-To: <20250122181659.GB34562@noisy.programming.kicks-ass.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/22/25 1:16 PM, Peter Zijlstra wrote: > On Wed, Jan 22, 2025 at 09:51:04AM -0500, Waiman Long wrote: > >> Anyway, do you think this patch is worth taking? There are may be other >> cases like this that are hiding somewhere and showing up from time to time. > No objection to the patch, we've been moving wakeup out from under the > lock locks for a while now. It just needs a new rationale, since the > changelog is a bit iffy as-is. OK, I will reword the change log and send a v2. Thanks, Longman