From patchwork Wed Jan 29 17:45:10 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Pitre X-Patchwork-Id: 23895 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-qa0-f70.google.com (mail-qa0-f70.google.com [209.85.216.70]) by ip-10-151-82-157.ec2.internal (Postfix) with ESMTPS id 2FF01202FA for ; Wed, 29 Jan 2014 17:47:10 +0000 (UTC) Received: by mail-qa0-f70.google.com with SMTP id ii20sf4285225qab.1 for ; Wed, 29 Jan 2014 09:47:09 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:delivered-to:from:to:cc:subject :date:message-id:in-reply-to:references:sender:precedence:list-id :x-original-sender:x-original-authentication-results:mailing-list :list-post:list-help:list-archive:list-unsubscribe :content-transfer-encoding; bh=JP6RzzxSzGxW1syXOsJjbaE4CIJjMAoDTPe/g/PiPJ4=; b=gj3GUrkLr759gNG0dKPtqcSot9OmEABYdLexYG4/kwJ3DAVY0zNGlQ/h0++o7Moqhe fUHaoNZyvVk4ouutmPz579nZtbStBMmSQlsXwZcfZhaq4hhuJZF/g2B3klZT5DLUKF5c 6fvVXg2tvvAFgk133cfsQIow5zKfYFcF452KmnEIy96O0Yibeq9gP0R6YhJNX3cgk3H1 lHvCYsaC9iPOsx31G4/jddgkl+gOSd8nF9pjwp0WapfnqQfnw77xJt+dJGZk/zNyV4su TnRyipZoULkeygmCUfsv29yRvE0dFsqnKF9rDI1My/XOTYcjuUmoixYnauAgQyqZsH9A X8rw== X-Gm-Message-State: ALoCoQn9fMdWedBSXMtsuypjHr0mR/9NmxAkJtmdGuaZMW0PSK8aff3dD+aydYMRhGKFkKqaj0ND X-Received: by 10.58.169.5 with SMTP id aa5mr3080347vec.37.1391017629339; Wed, 29 Jan 2014 09:47:09 -0800 (PST) MIME-Version: 1.0 X-BeenThere: patchwork-forward@linaro.org Received: by 10.140.21.8 with SMTP id 8ls210729qgk.51.gmail; Wed, 29 Jan 2014 09:47:09 -0800 (PST) X-Received: by 10.52.248.10 with SMTP id yi10mr752969vdc.39.1391017629091; Wed, 29 Jan 2014 09:47:09 -0800 (PST) Received: from mail-vc0-f169.google.com (mail-vc0-f169.google.com [209.85.220.169]) by mx.google.com with ESMTPS id dd4si1017899vcb.70.2014.01.29.09.47.09 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 29 Jan 2014 09:47:09 -0800 (PST) Received-SPF: neutral (google.com: 209.85.220.169 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) client-ip=209.85.220.169; Received: by mail-vc0-f169.google.com with SMTP id hq11so1427875vcb.28 for ; Wed, 29 Jan 2014 09:47:09 -0800 (PST) X-Received: by 10.58.123.70 with SMTP id ly6mr2046208veb.26.1391017628984; Wed, 29 Jan 2014 09:47:08 -0800 (PST) X-Forwarded-To: patchwork-forward@linaro.org X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org Delivered-To: patch@linaro.org Received: by 10.220.174.196 with SMTP id u4csp132712vcz; Wed, 29 Jan 2014 09:47:08 -0800 (PST) X-Received: by 10.66.14.41 with SMTP id m9mr9441558pac.123.1391017627883; Wed, 29 Jan 2014 09:47:07 -0800 (PST) Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id pk8si3411073pab.213.2014.01.29.09.47.07; Wed, 29 Jan 2014 09:47:07 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752999AbaA2RrA (ORCPT + 27 others); Wed, 29 Jan 2014 12:47:00 -0500 Received: from relais.videotron.ca ([24.201.245.36]:21485 "EHLO relais.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752153AbaA2RpW (ORCPT ); Wed, 29 Jan 2014 12:45:22 -0500 Received: from yoda.home ([66.130.143.177]) by VL-VM-MR006.ip.videotron.ca (Oracle Communications Messaging Exchange Server 7u4-22.01 64bit (built Apr 21 2011)) with ESMTP id <0N0600B0KBZJ6U80@VL-VM-MR006.ip.videotron.ca>; Wed, 29 Jan 2014 12:45:19 -0500 (EST) Received: from xanadu.home (xanadu.home [192.168.2.2]) by yoda.home (Postfix) with ESMTP id 2E1912DA06FC; Wed, 29 Jan 2014 12:45:19 -0500 (EST) From: Nicolas Pitre To: Russell King , Benjamin Herrenschmidt , Preeti U Murthy , Paul Mundt , Thomas Gleixner , Ingo Molnar , Peter Zijlstra , "Rafael J. Wysocki" , Daniel Lezcano Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-sh@vger.kernel.org, linux-pm@vger.kernel.org, linaro-kernel@lists.linaro.org Subject: [PATCH v2 3/6] PPC: remove redundant cpuidle_idle_call() Date: Wed, 29 Jan 2014 12:45:10 -0500 Message-id: <1391017513-12995-4-git-send-email-nicolas.pitre@linaro.org> X-Mailer: git-send-email 1.8.4.108.g55ea5f6 In-reply-to: <1391017513-12995-1-git-send-email-nicolas.pitre@linaro.org> References: <1391017513-12995-1-git-send-email-nicolas.pitre@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: list List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Removed-Original-Auth: Dkim didn't pass. X-Original-Sender: nicolas.pitre@linaro.org X-Original-Authentication-Results: mx.google.com; spf=neutral (google.com: 209.85.220.169 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) smtp.mail=patch+caf_=patchwork-forward=linaro.org@linaro.org Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org X-Google-Group-Id: 836684582541 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , Content-transfer-encoding: 7BIT The core idle loop now takes care of it. However a few things need checking: - Invocation of cpuidle_idle_call() in pseries_lpar_idle() happened through arch_cpu_idle() and was therefore always preceded by a call to ppc64_runlatch_off(). To preserve this property now that cpuidle_idle_call() is invoked directly from core code, a call to ppc64_runlatch_off() has been added to idle_loop_prolog() in platforms/pseries/processor_idle.c. - Similarly, cpuidle_idle_call() was followed by ppc64_runlatch_off() so a call to the later has been added to idle_loop_epilog(). - And since arch_cpu_idle() always made sure to re-enable IRQs if they were not enabled, this is now done in idle_loop_epilog() as well. The above was made in order to keep the execution flow close to the original. I don't know if that was strictly necessary. Someone well aquainted with the platform details might find some room for possible optimizations. Signed-off-by: Nicolas Pitre Reviewed-by: Preeti U Murthy --- arch/powerpc/platforms/pseries/processor_idle.c | 5 ++++ arch/powerpc/platforms/pseries/setup.c | 34 ++++++++++--------------- 2 files changed, 19 insertions(+), 20 deletions(-) diff --git a/arch/powerpc/platforms/pseries/processor_idle.c b/arch/powerpc/platforms/pseries/processor_idle.c index a166e38bd6..72ddfe3d2f 100644 --- a/arch/powerpc/platforms/pseries/processor_idle.c +++ b/arch/powerpc/platforms/pseries/processor_idle.c @@ -33,6 +33,7 @@ static struct cpuidle_state *cpuidle_state_table; static inline void idle_loop_prolog(unsigned long *in_purr) { + ppc64_runlatch_off(); *in_purr = mfspr(SPRN_PURR); /* * Indicate to the HV that we are idle. Now would be @@ -49,6 +50,10 @@ static inline void idle_loop_epilog(unsigned long in_purr) wait_cycles += mfspr(SPRN_PURR) - in_purr; get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles); get_lppaca()->idle = 0; + + if (irqs_disabled()) + local_irq_enable(); + ppc64_runlatch_on(); } static int snooze_loop(struct cpuidle_device *dev, diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index c1f1908587..7604c19d54 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -39,7 +39,6 @@ #include #include #include -#include #include #include @@ -356,29 +355,24 @@ early_initcall(alloc_dispatch_log_kmem_cache); static void pseries_lpar_idle(void) { - /* This would call on the cpuidle framework, and the back-end pseries - * driver to go to idle states + /* + * Default handler to go into low thread priority and possibly + * low power mode by cedeing processor to hypervisor */ - if (cpuidle_idle_call()) { - /* On error, execute default handler - * to go into low thread priority and possibly - * low power mode by cedeing processor to hypervisor - */ - /* Indicate to hypervisor that we are idle. */ - get_lppaca()->idle = 1; + /* Indicate to hypervisor that we are idle. */ + get_lppaca()->idle = 1; - /* - * Yield the processor to the hypervisor. We return if - * an external interrupt occurs (which are driven prior - * to returning here) or if a prod occurs from another - * processor. When returning here, external interrupts - * are enabled. - */ - cede_processor(); + /* + * Yield the processor to the hypervisor. We return if + * an external interrupt occurs (which are driven prior + * to returning here) or if a prod occurs from another + * processor. When returning here, external interrupts + * are enabled. + */ + cede_processor(); - get_lppaca()->idle = 0; - } + get_lppaca()->idle = 0; } /*