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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4852470620dsm26368725e9.27.2026.03.06.15.01.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Mar 2026 15:01:16 -0800 (PST) Date: Fri, 6 Mar 2026 23:01:14 +0000 From: David Laight To: Waiman Long , Peter Zijlstra , Ingo Molnar , Will Deacon , Boqun Feng , linux-kernel@vger.kernel.org, Linus Torvalds , Yafang Shao , Steven Rostedt Subject: Re: [PATCH v3 next 1/5] Only clear node->locked in the slow osq_lock() path Message-ID: <20260306230114.74a7fc23@pumpkin> In-Reply-To: <20260306225150.93178-2-david.laight.linux@gmail.com> References: <20260306225150.93178-1-david.laight.linux@gmail.com> <20260306225150.93178-2-david.laight.linux@gmail.com> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 6 Mar 2026 22:51:46 +0000 david.laight.linux@gmail.com wrote: Apologies to Yafang for mistyping his address... > From: David Laight > > node->locked is used to indicate that the owner of the lock has handed it > off to the waiting CPU. > As such it's value is only relevant in the slow path so it need not be > initialised in the fast path. > > Signed-off-by: David Laight > --- > kernel/locking/osq_lock.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/locking/osq_lock.c b/kernel/locking/osq_lock.c > index b4233dc2c2b0..96c6094157b5 100644 > --- a/kernel/locking/osq_lock.c > +++ b/kernel/locking/osq_lock.c > @@ -97,7 +97,6 @@ bool osq_lock(struct optimistic_spin_queue *lock) > int curr = encode_cpu(smp_processor_id()); > int old; > > - node->locked = 0; > node->next = NULL; > node->cpu = curr; > > @@ -113,6 +112,7 @@ bool osq_lock(struct optimistic_spin_queue *lock) > > prev = decode_cpu(old); > node->prev = prev; > + node->locked = 0; > > /* > * osq_lock() unqueue