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=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,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 4C725C433E0 for ; Thu, 21 Jan 2021 11:06:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 028182388E for ; Thu, 21 Jan 2021 11:06:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729925AbhAULFy (ORCPT ); Thu, 21 Jan 2021 06:05:54 -0500 Received: from mout.gmx.net ([212.227.15.18]:59393 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730194AbhAULD1 (ORCPT ); Thu, 21 Jan 2021 06:03:27 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1611226897; bh=eYAy1J2NKCY+RyTEa0EWRFh3SqSrlZL9klmVxa9DBP0=; h=X-UI-Sender-Class:Subject:From:In-Reply-To:Date:Cc:References:To; b=KsNcBfRlO4MSYxzNTo+lKweEPmFbUpKuAC3FzA6e08+GmeL6/8h2jidgKh8PiWoG0 8qIlEtt5D06Sroy3Ib2b2pFvL2N3q6f1ioziwFYIBysqEW18OwhkCfjlrrEWfBTL9j bs9GO8CAGR5gBgJdgkS6Kd3JP8vamgludLOcKXpU= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from rainbow.home ([83.204.192.78]) by mail.gmx.net (mrgmx004 [212.227.17.184]) with ESMTPSA (Nemesis) id 1Mnpns-1lnQzr34Ru-00pPgR; Thu, 21 Jan 2021 12:01:37 +0100 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.60.0.2.5\)) Subject: Re: [RFC PATCH 2/7] arm64: kernel: Add a WFI hook. From: Mohamed Mediouni In-Reply-To: Date: Thu, 21 Jan 2021 12:01:35 +0100 Cc: Linux ARM , Mark Rutland , Catalin Marinas , Hector Martin , "linux-kernel@vger.kernel.org" , Marc Zyngier , Will Deacon , Stan Skowronek Content-Transfer-Encoding: quoted-printable Message-Id: <5403A355-A4FA-442B-8F8B-5629FCECC006@caramail.com> References: <20210120132717.395873-1-mohamed.mediouni@caramail.com> <20210120132717.395873-3-mohamed.mediouni@caramail.com> To: Arnd Bergmann X-Mailer: Apple Mail (2.3654.60.0.2.5) X-Provags-ID: V03:K1:I2JAzLKjoXvPuwdCtfo/qK44jRV3D6+4JtEipYPBpKJkz3GnCCr LkAhBQ12Y/bZRdq6BmPN2YLEwma0r31aHHK7kwT7bIMwdPIZ5iWubXqFKJbKB0PcXx6BKkr f+yaEblViJDEjLfdBxyfPEQADVDCrode8YonnEWKA6/D0AihKSKe3K0dzui7TNXtsxceBa6 Y7inpx4RMktYGHpRQPArA== X-UI-Out-Filterresults: notjunk:1;V03:K0:MlMw1I/SbqU=:0SX2+4xrMQRL/VGj2YF9JI 4zQSFzEI/qsJ/dnqlx9IfJe4WYjfhx8/rgF62KUOiVBliOhvsVXK3yLX6tS9hc4TS+b88UrJk //V96TeDHPX8DblX4BM/15Ya93JMcOrRZMmCa+5xz1hIpBNZPTVEGpd2WukHHgo/whwl7fahh v5FSKiY1Hp90CrS6GiwhD5/jnZo3LrEIlISODE9MKWhlXWbQOvpLsYq+7O6TU2W6j4l6prwKP NSQN4Mq9+qmeDAXtmph+ZmwQcwndLRZFEQdKrSrgbfBH9ngz6Vs4rpY2y/t8RFJl9rQ9j4Smh W+ZwYdco2OfQh+3PpSypaSRurv0+fCXt0l/6fQZnED/UovKevCyrz09rCq/GdNd8rrvHMdnOq BQfPiR9DC14J8QNtoOmrmIJdYijPp+Y+KCUX9x+CyZpW3sqmZ1RLROjsAIieIxT7wUatsL7ys I2GLh8fNUNOrcGHqqAJH2QB1GdLNSt6m8PiCZCLtQ76rGs+5oDYZ0K5JWtdMtGn3YhOr2/X1t ygdK5DWYcmDbqT9xgY5Faeip41FlhEPc6CfHtYg5Wkvr5use1scmV6KRwTLCO42xFkRyhDE7w D3gJul9AANgOJzn0RxgtC700I78IETIRm9dk/uLx3IvK7EZTlC9cUZIB/VJ3JFlLoHtefEP+B 9fQXtiN/KDi1LGLAVyN2ESlWiJ4sH2qUc6K1nLLCpF2dU6mjQATo6urFSZvArOUgVjvlforFZ cGu8+axz5WXFp6jpBFGi7MMI2tRyQw+WjUbQ1jOta9VUNnMNeAAjtrgj3auavUblnb0auOTbo ywu/JLrmMBFRW53bkykqm0kfoY0EQPQffjw3NolNExLzSi25LzgAjxdZmnHMvXdZD5YOnwDX9 jjSWuzlt7wn/LrVN8eCCas86PLjU5+PAeshTgxfts= Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On 21 Jan 2021, at 11:52, Arnd Bergmann wrote: >=20 > On Wed, Jan 20, 2021 at 2:27 PM Mohamed Mediouni > wrote: >> --- a/arch/arm64/kernel/cpu_ops.c >> +++ b/arch/arm64/kernel/cpu_ops.c >=20 >> #if defined(CONFIG_STACKPROTECTOR) && = !defined(CONFIG_STACKPROTECTOR_PER_TASK) >> #include >> @@ -74,8 +75,14 @@ void (*arm_pm_restart)(enum reboot_mode = reboot_mode, const char *cmd); >>=20 >> static void noinstr __cpu_do_idle(void) >> { >> - dsb(sy); >> - wfi(); >> + const struct cpu_operations *ops =3D = get_cpu_ops(task_cpu(current)); >> + >> + if (ops->cpu_wfi) { >> + ops->cpu_wfi(); >> + } else { >> + dsb(sy); >> + wfi(); >> + } >> } >=20 > I think the correct place to put this would be a platform specific = driver > in drivers/cpuidle/ instead of an added low-level callback in the > default idle function and a custom cpu_operations structure. Can we make sure that wfi never gets called even on early boot when using a cpuidle driver? Thank you, >=20 > Arnd 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=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,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 19BC6C433DB for ; Thu, 21 Jan 2021 11:03:45 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 B131E23602 for ; Thu, 21 Jan 2021 11:03:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B131E23602 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=caramail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+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=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:To:References:Message-Id:Date:In-Reply-To:From: Subject:Mime-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=+IwGd5fxjmPN3argdEaTxQTBccH5PQD0HUPpD72nj94=; b=XhZ/cgmOL4RkNkzITXNl9DMl/ XTWtNY4m4VYafG/YFerwSZCy33/RyuPmj91Op3h9vIS7H2XUT7QZoSeolFHzd7GsV1eEYTU6l8SPQ hHh3PgP0cw0e3J9HJJjK9HUX82qwS2AhkT90Mvipn0Zsi+dKMWp0a2rZBELfc75mHcePGg0s0HZE7 +zSwaSyo4w9hM5vnX6AY2Qu+AZFqneHGKMqXB6bnfQNlRX6Cmwi27ynPmPUZ54JsDU9F/iAVWaH6B RvpWZBqU2zBXtmeGYHmGbXkT5qgnKQdm9ab3QxhjQGVdnpcyv5iJjnqJDPpM1CdsaVzVk1qoN8qXL /nWr8ltDA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l2Xir-0002HX-9f; Thu, 21 Jan 2021 11:01:53 +0000 Received: from mout.gmx.net ([212.227.15.18]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l2Xij-0002Et-Nh for linux-arm-kernel@lists.infradead.org; Thu, 21 Jan 2021 11:01:49 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1611226897; bh=eYAy1J2NKCY+RyTEa0EWRFh3SqSrlZL9klmVxa9DBP0=; h=X-UI-Sender-Class:Subject:From:In-Reply-To:Date:Cc:References:To; b=KsNcBfRlO4MSYxzNTo+lKweEPmFbUpKuAC3FzA6e08+GmeL6/8h2jidgKh8PiWoG0 8qIlEtt5D06Sroy3Ib2b2pFvL2N3q6f1ioziwFYIBysqEW18OwhkCfjlrrEWfBTL9j bs9GO8CAGR5gBgJdgkS6Kd3JP8vamgludLOcKXpU= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from rainbow.home ([83.204.192.78]) by mail.gmx.net (mrgmx004 [212.227.17.184]) with ESMTPSA (Nemesis) id 1Mnpns-1lnQzr34Ru-00pPgR; Thu, 21 Jan 2021 12:01:37 +0100 Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.60.0.2.5\)) Subject: Re: [RFC PATCH 2/7] arm64: kernel: Add a WFI hook. From: Mohamed Mediouni In-Reply-To: Date: Thu, 21 Jan 2021 12:01:35 +0100 Message-Id: <5403A355-A4FA-442B-8F8B-5629FCECC006@caramail.com> References: <20210120132717.395873-1-mohamed.mediouni@caramail.com> <20210120132717.395873-3-mohamed.mediouni@caramail.com> To: Arnd Bergmann X-Mailer: Apple Mail (2.3654.60.0.2.5) X-Provags-ID: V03:K1:I2JAzLKjoXvPuwdCtfo/qK44jRV3D6+4JtEipYPBpKJkz3GnCCr LkAhBQ12Y/bZRdq6BmPN2YLEwma0r31aHHK7kwT7bIMwdPIZ5iWubXqFKJbKB0PcXx6BKkr f+yaEblViJDEjLfdBxyfPEQADVDCrode8YonnEWKA6/D0AihKSKe3K0dzui7TNXtsxceBa6 Y7inpx4RMktYGHpRQPArA== X-UI-Out-Filterresults: notjunk:1;V03:K0:MlMw1I/SbqU=:0SX2+4xrMQRL/VGj2YF9JI 4zQSFzEI/qsJ/dnqlx9IfJe4WYjfhx8/rgF62KUOiVBliOhvsVXK3yLX6tS9hc4TS+b88UrJk //V96TeDHPX8DblX4BM/15Ya93JMcOrRZMmCa+5xz1hIpBNZPTVEGpd2WukHHgo/whwl7fahh v5FSKiY1Hp90CrS6GiwhD5/jnZo3LrEIlISODE9MKWhlXWbQOvpLsYq+7O6TU2W6j4l6prwKP NSQN4Mq9+qmeDAXtmph+ZmwQcwndLRZFEQdKrSrgbfBH9ngz6Vs4rpY2y/t8RFJl9rQ9j4Smh W+ZwYdco2OfQh+3PpSypaSRurv0+fCXt0l/6fQZnED/UovKevCyrz09rCq/GdNd8rrvHMdnOq BQfPiR9DC14J8QNtoOmrmIJdYijPp+Y+KCUX9x+CyZpW3sqmZ1RLROjsAIieIxT7wUatsL7ys I2GLh8fNUNOrcGHqqAJH2QB1GdLNSt6m8PiCZCLtQ76rGs+5oDYZ0K5JWtdMtGn3YhOr2/X1t ygdK5DWYcmDbqT9xgY5Faeip41FlhEPc6CfHtYg5Wkvr5use1scmV6KRwTLCO42xFkRyhDE7w D3gJul9AANgOJzn0RxgtC700I78IETIRm9dk/uLx3IvK7EZTlC9cUZIB/VJ3JFlLoHtefEP+B 9fQXtiN/KDi1LGLAVyN2ESlWiJ4sH2qUc6K1nLLCpF2dU6mjQATo6urFSZvArOUgVjvlforFZ cGu8+axz5WXFp6jpBFGi7MMI2tRyQw+WjUbQ1jOta9VUNnMNeAAjtrgj3auavUblnb0auOTbo ywu/JLrmMBFRW53bkykqm0kfoY0EQPQffjw3NolNExLzSi25LzgAjxdZmnHMvXdZD5YOnwDX9 jjSWuzlt7wn/LrVN8eCCas86PLjU5+PAeshTgxfts= X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210121_060145_990799_B74E7030 X-CRM114-Status: GOOD ( 15.56 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Catalin Marinas , Hector Martin , "linux-kernel@vger.kernel.org" , Marc Zyngier , Will Deacon , Linux ARM , Stan Skowronek Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org > On 21 Jan 2021, at 11:52, Arnd Bergmann wrote: > > On Wed, Jan 20, 2021 at 2:27 PM Mohamed Mediouni > wrote: >> --- a/arch/arm64/kernel/cpu_ops.c >> +++ b/arch/arm64/kernel/cpu_ops.c > >> #if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_STACKPROTECTOR_PER_TASK) >> #include >> @@ -74,8 +75,14 @@ void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd); >> >> static void noinstr __cpu_do_idle(void) >> { >> - dsb(sy); >> - wfi(); >> + const struct cpu_operations *ops = get_cpu_ops(task_cpu(current)); >> + >> + if (ops->cpu_wfi) { >> + ops->cpu_wfi(); >> + } else { >> + dsb(sy); >> + wfi(); >> + } >> } > > I think the correct place to put this would be a platform specific driver > in drivers/cpuidle/ instead of an added low-level callback in the > default idle function and a custom cpu_operations structure. Can we make sure that wfi never gets called even on early boot when using a cpuidle driver? Thank you, > > Arnd _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel