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=-14.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 65C80C43465 for ; Mon, 21 Sep 2020 12:44:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 261EC216C4 for ; Mon, 21 Sep 2020 12:44:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600692285; bh=RiX+BSZ4KRO/DAXyDAv+zh65c7YSo5yRo7XqYYkYA0o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BH9WSl07sX+5KvM2lAMvrQflI6B8QHkT5hwhK1kMWjNtWudYJrCTADNI3YXJB7JMB 1qsWa6UhYqXxG3oJdYf8nPXEi4TMeYyn/puTbzAOcXjBaY0Q6MGpgW/2Gk8rd8Ufuh GLntliQ323xjdmz1azREAUm49GsuCP21g4xrNkHQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727099AbgIUMok (ORCPT ); Mon, 21 Sep 2020 08:44:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:54768 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727009AbgIUMoY (ORCPT ); Mon, 21 Sep 2020 08:44:24 -0400 Received: from lenoir.home (lfbn-ncy-1-588-162.w81-51.abo.wanadoo.fr [81.51.203.162]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B864121D95; Mon, 21 Sep 2020 12:44:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600692260; bh=RiX+BSZ4KRO/DAXyDAv+zh65c7YSo5yRo7XqYYkYA0o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BhDwomf+lHIb0Z4xOuoGMotcPDoUG/2qiPy+QnRfFLsNPjEe8t2SjbkbTOR1lC7hR Eh94PqxkvTtbB+KA2nP0vMxY3uHpbR5Z7sS3QZA1EERnjxN3Cl22bANpuOFRWZ3z4p zQ9RedjnKIKwvwLsYDe0vpeQ7Z5KeH82kY3ZFeew= From: Frederic Weisbecker To: "Paul E . McKenney" Cc: LKML , Frederic Weisbecker , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Joel Fernandes , Josh Triplett Subject: [RFC PATCH 11/12] rcu: Locally accelerate callbacks as long as offloading isn't complete Date: Mon, 21 Sep 2020 14:43:50 +0200 Message-Id: <20200921124351.24035-12-frederic@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200921124351.24035-1-frederic@kernel.org> References: <20200921124351.24035-1-frederic@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I have no idea what I'm doing but doing that looks necessary to me. Inspired-by: Paul E. McKenney Signed-off-by: Frederic Weisbecker Cc: Paul E. McKenney Cc: Josh Triplett Cc: Steven Rostedt Cc: Mathieu Desnoyers Cc: Lai Jiangshan Cc: Joel Fernandes --- kernel/rcu/tree.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 928907e9ba94..8cef5ea8d1f0 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2619,7 +2619,6 @@ static __latent_entropy void rcu_core(void) unsigned long flags; struct rcu_data *rdp = raw_cpu_ptr(&rcu_data); struct rcu_node *rnp = rdp->mynode; - const bool offloaded = rcu_segcblist_is_offloaded(&rdp->cblist); const bool do_batch = !rcu_segcblist_completely_offloaded(&rdp->cblist); if (cpu_is_offline(smp_processor_id())) @@ -2640,11 +2639,11 @@ static __latent_entropy void rcu_core(void) /* No grace period and unregistered callbacks? */ if (!rcu_gp_in_progress() && - rcu_segcblist_is_enabled(&rdp->cblist) && !offloaded) { - local_irq_save(flags); + rcu_segcblist_is_enabled(&rdp->cblist) && do_batch) { + rcu_nocb_lock_irqsave(rdp, flags); if (!rcu_segcblist_restempty(&rdp->cblist, RCU_NEXT_READY_TAIL)) rcu_accelerate_cbs_unlocked(rnp, rdp); - local_irq_restore(flags); + rcu_nocb_unlock_irqrestore(rdp, flags); } rcu_check_gp_start_stall(rnp, rdp, rcu_jiffies_till_stall_check()); -- 2.28.0