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From: Joel Fernandes <joelagnelf@nvidia.com>
To: linux-kernel@vger.kernel.org,
	"Paul E. McKenney" <paulmck@kernel.org>,
	Frederic Weisbecker <frederic@kernel.org>,
	Neeraj Upadhyay <neeraj.upadhyay@kernel.org>,
	Joel Fernandes <joelagnelf@nvidia.com>,
	Josh Triplett <josh@joshtriplett.org>,
	Boqun Feng <boqun@kernel.org>,
	Uladzislau Rezki <urezki@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Lai Jiangshan <jiangshanlai@gmail.com>,
	Zqiang <qiang.zhang@linux.dev>
Cc: rcu@vger.kernel.org
Subject: [PATCH -next v1 13/16] rcu-tasks: Remove unnecessary smp_store_release() in cblist_init_generic()
Date: Tue, 17 Mar 2026 17:22:14 -0400	[thread overview]
Message-ID: <20260317212217.1527644-14-joelagnelf@nvidia.com> (raw)
In-Reply-To: <20260317212217.1527644-1-joelagnelf@nvidia.com>

From: Zqiang <qiang.zhang@linux.dev>

The cblist_init_generic() is executed during the CPU early boot
phase due to commit:30ef09635b9e ("rcu-tasks: Initialize callback
lists at rcu_init() time"), at this time, only one boot CPU is
online and the irq is disabled. this commit therefore use routine
assignment replace of smp_store_release() and WRITE_ONCE() in the
cblist_init_generic().

Signed-off-by: Zqiang <qiang.zhang@linux.dev>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
---
 kernel/rcu/tasks.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 2b55e6acf3c1..48f0d803c8e2 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -291,9 +291,9 @@ static void cblist_init_generic(struct rcu_tasks *rtp)
 	shift = ilog2(rcu_task_cpu_ids / lim);
 	if (((rcu_task_cpu_ids - 1) >> shift) >= lim)
 		shift++;
-	WRITE_ONCE(rtp->percpu_enqueue_shift, shift);
-	WRITE_ONCE(rtp->percpu_dequeue_lim, lim);
-	smp_store_release(&rtp->percpu_enqueue_lim, lim);
+	rtp->percpu_enqueue_shift = shift;
+	rtp->percpu_dequeue_lim = lim;
+	rtp->percpu_enqueue_lim = lim;
 
 	pr_info("%s: Setting shift to %d and lim to %d rcu_task_cb_adjust=%d rcu_task_cpu_ids=%d.\n",
 			rtp->name, data_race(rtp->percpu_enqueue_shift), data_race(rtp->percpu_enqueue_lim),
-- 
2.34.1


  parent reply	other threads:[~2026-03-17 21:23 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-17 21:22 [PATCH -next v1 00/16] Candidate patches for the v7.1 merge window Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 01/16] rcutorture: Add a textbook-style trivial preemptible RCU Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 02/16] kvm-check-branches.sh: Remove in favor of kvm-series.sh Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 03/16] torture: Make hangs more visible in torture.sh output Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 04/16] torture: Print informative message for test without recheck file Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 05/16] rcutorture: Fix numeric "test" comparison in srcu_lockdep.sh Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 06/16] refscale: Ditch ref_scale_shutdown in favor of torture_shutdown_init() Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 07/16] rcuscale: Ditch rcu_scale_shutdown " Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 08/16] srcu: Fix SRCU read flavor macro comments Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 09/16] srcu: Fix s/they disables/they disable/ typo in srcu_read_unlock_fast() Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 10/16] rcu-tasks: Document that RCU Tasks Trace grace periods now imply RCU grace periods Joel Fernandes
2026-03-18 11:04   ` Frederic Weisbecker
2026-03-18 12:15     ` Frederic Weisbecker
2026-03-17 21:22 ` [PATCH -next v1 11/16] rcutorture: Add NOCB01 config for RCU_LAZY torture testing Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 12/16] rcutorture: Add NOCB02 config for nocb poll mode testing Joel Fernandes
2026-03-17 21:22 ` Joel Fernandes [this message]
2026-03-18 10:57   ` [PATCH -next v1 13/16] rcu-tasks: Remove unnecessary smp_store_release() in cblist_init_generic() Frederic Weisbecker
2026-03-17 21:22 ` [PATCH -next v1 14/16] rcu/nocb: Consolidate rcu_nocb_cpu_offload/deoffload functions Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 15/16] rcu/nocb: Extract nocb_bypass_needs_flush() to reduce duplication Joel Fernandes
2026-03-17 21:22 ` [PATCH -next v1 16/16] torture: Avoid modulo-zero error in torture_hrtimeout_ns() Joel Fernandes

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