From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CB389C4332F for ; Wed, 15 Sep 2021 23:33:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B183961186 for ; Wed, 15 Sep 2021 23:33:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233016AbhIOXfF (ORCPT ); Wed, 15 Sep 2021 19:35:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:60386 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232908AbhIOXfE (ORCPT ); Wed, 15 Sep 2021 19:35:04 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0275761157; Wed, 15 Sep 2021 23:33:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631748825; bh=xsgx0GpeQAclTej5LlLjRn0cECyUgrdxHaCISoqSx7Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M8n9Zw0HEbwpFJDZyq0/hxL+uIVkcK9FXe+F51CN8/PjfyPMaO8EhDq9BdFqd1nDe segZn6INYpHiLJG2XYs/bcQ98esuxyHJZOZ29ua9xku1DuMXVtRlvONrpD8KH7CAfN CVrT8yqkVeb3TLoTaylAhuFFk1DmY23jMYQhhJ+WAJLMIb34ip9LBslJbiywUo8Acc fIUgaioS5onWEEg5kfNCaXLmQNRp1AKnFvz4g7tNoFtyWzdlsDxRAGAi8OyDtrwOkE AuOdkEdJTujWkvwcU3wVK63pVuBpQ3rPaeVYeTuqkaS08ze9HEqTwrL5g3r5+41Q2c f/7gg4NVPeGQw== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id C13A55C08E8; Wed, 15 Sep 2021 16:33:44 -0700 (PDT) From: "Paul E. McKenney" To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, "Paul E. McKenney" Subject: [PATCH rcu 04/14] rcu: Eliminate rcu_implicit_dynticks_qs() local variable ruqp Date: Wed, 15 Sep 2021 16:33:33 -0700 Message-Id: <20210915233343.3906738-4-paulmck@kernel.org> X-Mailer: git-send-email 2.31.1.189.g2e36527f23 In-Reply-To: <20210915233305.GA3906641@paulmck-ThinkPad-P17-Gen-1> References: <20210915233305.GA3906641@paulmck-ThinkPad-P17-Gen-1> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org The rcu_implicit_dynticks_qs() function's local variable ruqp references the ->rcu_urgent_qs field in the rcu_data structure referenced by the function parameter rdp, with a rather odd method for computing the pointer to this field. This commit therefore simplifies things and saves a couple of lines of code by replacing each instance of ruqp with &rdp->need_heavy_qs. Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 18d2f35d1450..0bfebec94277 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1219,7 +1219,6 @@ static int dyntick_save_progress_counter(struct rcu_data *rdp) static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) { unsigned long jtsq; - bool *ruqp; struct rcu_node *rnp = rdp->mynode; /* @@ -1284,16 +1283,15 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) * is set way high. */ jtsq = READ_ONCE(jiffies_to_sched_qs); - ruqp = per_cpu_ptr(&rcu_data.rcu_urgent_qs, rdp->cpu); if (!READ_ONCE(rdp->rcu_need_heavy_qs) && (time_after(jiffies, rcu_state.gp_start + jtsq * 2) || time_after(jiffies, rcu_state.jiffies_resched) || rcu_state.cbovld)) { WRITE_ONCE(rdp->rcu_need_heavy_qs, true); /* Store rcu_need_heavy_qs before rcu_urgent_qs. */ - smp_store_release(ruqp, true); + smp_store_release(&rdp->rcu_urgent_qs, true); } else if (time_after(jiffies, rcu_state.gp_start + jtsq)) { - WRITE_ONCE(*ruqp, true); + WRITE_ONCE(rdp->rcu_urgent_qs, true); } /* @@ -1307,7 +1305,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) if (tick_nohz_full_cpu(rdp->cpu) && (time_after(jiffies, READ_ONCE(rdp->last_fqs_resched) + jtsq * 3) || rcu_state.cbovld)) { - WRITE_ONCE(*ruqp, true); + WRITE_ONCE(rdp->rcu_urgent_qs, true); resched_cpu(rdp->cpu); WRITE_ONCE(rdp->last_fqs_resched, jiffies); } -- 2.31.1.189.g2e36527f23