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=-6.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 407A3C388F7 for ; Wed, 28 Oct 2020 21:51:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C70ED2245A for ; Wed, 28 Oct 2020 21:51:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="YtufiS6T" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727687AbgJ1Vvp (ORCPT ); Wed, 28 Oct 2020 17:51:45 -0400 Received: from casper.infradead.org ([90.155.50.34]:44160 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728190AbgJ1Vvk (ORCPT ); Wed, 28 Oct 2020 17:51:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=nRbxEu5PHWvaZU3cUIDAJ1KT7k+wxj/W0tlXERUkaAk=; b=YtufiS6TFoTGsEomrgrre39K0p P2O2XgMJ/8XAYkSmikRvG5Pt02tBpMvKFSTmsnMQhmHWZYxBI+g77MRHvqhvPEImJF03euGcOeVez AOnSVBa7b591V8joDArJh+sXAnJQfzXbJ8f0xR9F5TgSdXw3CqfMZ/JZ4hHPWB3aY2DQVX2TWtIAX Z7MDQzk1FZx+NMtP0hYmXKuostdncwxv32Fi73Q4hZjleYQpshkbC1nlaan7t8xkw1QOZQZ32pgDU dyDR0mwviJSvglDW7zaa6zFdjaMkiCGIbYewYEQWH4YkUTmZr/gImANe3Y4kBkT0PBylB8r/H/c9j uL1U7tGw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kXjON-0000Pv-AI; Wed, 28 Oct 2020 11:13:24 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 5E03E3062EA; Wed, 28 Oct 2020 12:13:22 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id DAD6A20B285AC; Wed, 28 Oct 2020 12:13:21 +0100 (CET) Message-ID: <20201028111221.584884062@infradead.org> User-Agent: quilt/0.66 Date: Wed, 28 Oct 2020 12:07:13 +0100 From: Peter Zijlstra To: mingo@kernel.org Cc: linux-kernel@vger.kernel.org, will@kernel.org, paulmck@kernel.org, hch@lst.de, axboe@kernel.dk, chris@chris-wilson.co.uk, davem@davemloft.net, kuba@kernel.org, fweisbec@gmail.com, oleg@redhat.com, vincent.guittot@linaro.org, peterz@infradead.org Subject: [RFC][PATCH v3 6/6] rcu/tree: Use irq_work_queue_remote() References: <20201028110707.971887448@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org AFAICT we only need/use irq_work_queue_on() on remote CPUs, since we can directly access local state. So avoid the IRQ_WORK dependency and use the unconditionally available irq_work_queue_remote(). This survives a number of TREE01 runs. Signed-off-by: Peter Zijlstra (Intel) --- kernel/rcu/tree.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1308,14 +1308,12 @@ static int rcu_implicit_dynticks_qs(stru resched_cpu(rdp->cpu); WRITE_ONCE(rdp->last_fqs_resched, jiffies); } -#ifdef CONFIG_IRQ_WORK if (!rdp->rcu_iw_pending && rdp->rcu_iw_gp_seq != rnp->gp_seq && (rnp->ffmask & rdp->grpmask)) { rdp->rcu_iw_pending = true; rdp->rcu_iw_gp_seq = rnp->gp_seq; - irq_work_queue_on(&rdp->rcu_iw, rdp->cpu); + irq_work_queue_remote(rdp->cpu, &rdp->rcu_iw); } -#endif } return 0;