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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 E29A8C282C2 for ; Wed, 13 Feb 2019 13:19:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B8239222B1 for ; Wed, 13 Feb 2019 13:19:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390518AbfBMNTd (ORCPT ); Wed, 13 Feb 2019 08:19:33 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:53482 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390491AbfBMNTb (ORCPT ); Wed, 13 Feb 2019 08:19:31 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C669A1596; Wed, 13 Feb 2019 05:19:30 -0800 (PST) Received: from brain-police (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4B3D13F557; Wed, 13 Feb 2019 05:19:28 -0800 (PST) Date: Wed, 13 Feb 2019 13:19:25 +0000 From: Will Deacon To: Mars Cheng Cc: Catalin Marinas , Matthias Brugger , "Paul E. McKenney" , CC Hwang , Loda Chou , linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, wsd_upstream@mediatek.com Subject: Re: [PATCH 1/1] arm64: Use _rcuidle for smp_cross_call() tracepoints Message-ID: <20190213131924.GD5875@brain-police> References: <1549969765-3707-1-git-send-email-mars.cheng@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1549969765-3707-1-git-send-email-mars.cheng@mediatek.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 12, 2019 at 07:09:25PM +0800, Mars Cheng wrote: > fix similar issue for aarch64 as the commit 7c64cc0531fa > ("arm: Use _rcuidle for smp_cross_call() tracepoints") fixed > in aarch32 I'm not convinced about this justification. As far as I can tell, the commit mentioned above fixed a cross-call from the idle path as a result of ARCH_NEEDS_CPU_IDLE_COUPLED, but this never appears to be selected on arm64 afaict. Are you actually seeing a problem on arm64 in practice? Will 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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT 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 2356AC282C2 for ; Wed, 13 Feb 2019 13:19:37 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E7C7A222B5 for ; Wed, 13 Feb 2019 13:19:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Mv03Rzbt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E7C7A222B5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=0BG/APJ7D2J3Cvn/CQAC29h/EUaw+MgR/C2gj+gmoP4=; b=Mv03Rzbt+6VawF nyTjdWQbZa3ABIz2zWK5dhOlnZ80YU4XLkH4n29kdS/ebRHlGMbPj0dHaNCaaVUhqtPOTl3KhLYhh QQ3FKP3cCv8w/H836qxmx1xYN/tlatvAmcX8kMuwo6CGo6vx6f12TvDxZLsIJeOTBGaNnTXgYYaBe 1E6/hgxRrUxreW/wPmYNP9qCaF5VB6N51tusr5jswivnlFaz41Up5gAJyNM/TJ9PaOvoxRI0EtKTI /+Vb0ILKlM/c43mjRoxVHQqsB4ht6FYSJuWdmJL/y9XFgW88AhRLkJIrdy2FXHHGPxUDH8FoPL3w/ JhY6565UN2Z3N9AkF0fw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gtuRr-0006ew-Gz; Wed, 13 Feb 2019 13:19:35 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gtuRn-0006cX-3s; Wed, 13 Feb 2019 13:19:32 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C669A1596; Wed, 13 Feb 2019 05:19:30 -0800 (PST) Received: from brain-police (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4B3D13F557; Wed, 13 Feb 2019 05:19:28 -0800 (PST) Date: Wed, 13 Feb 2019 13:19:25 +0000 From: Will Deacon To: Mars Cheng Subject: Re: [PATCH 1/1] arm64: Use _rcuidle for smp_cross_call() tracepoints Message-ID: <20190213131924.GD5875@brain-police> References: <1549969765-3707-1-git-send-email-mars.cheng@mediatek.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1549969765-3707-1-git-send-email-mars.cheng@mediatek.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190213_051931_162289_078B9026 X-CRM114-Status: GOOD ( 10.52 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: CC Hwang , wsd_upstream@mediatek.com, Catalin Marinas , Loda Chou , linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, Matthias Brugger , "Paul E. McKenney" , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Feb 12, 2019 at 07:09:25PM +0800, Mars Cheng wrote: > fix similar issue for aarch64 as the commit 7c64cc0531fa > ("arm: Use _rcuidle for smp_cross_call() tracepoints") fixed > in aarch32 I'm not convinced about this justification. As far as I can tell, the commit mentioned above fixed a cross-call from the idle path as a result of ARCH_NEEDS_CPU_IDLE_COUPLED, but this never appears to be selected on arm64 afaict. Are you actually seeing a problem on arm64 in practice? Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel