From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752468AbaBKMTy (ORCPT ); Tue, 11 Feb 2014 07:19:54 -0500 Received: from terminus.zytor.com ([198.137.202.10]:46636 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751359AbaBKMTu (ORCPT ); Tue, 11 Feb 2014 07:19:50 -0500 Date: Tue, 11 Feb 2014 04:18:08 -0800 From: tip-bot for Nicolas Pitre Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, peterz@infradead.org, nicolas.pitre@linaro.org, lethal@linux-sh.org, benh@kernel.crashing.org, linux@arm.linux.org.uk, preeti@linux.vnet.ibm.com, nico@linaro.org, tglx@linutronix.de, rjw@rjwysocki.net, daniel.lezcano@linaro.org Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, peterz@infradead.org, nicolas.pitre@linaro.org, lethal@linux-sh.org, benh@kernel.crashing.org, preeti@linux.vnet.ibm.com, linux@arm.linux.org.uk, nico@linaro.org, rjw@rjwysocki.net, tglx@linutronix.de, daniel.lezcano@linaro.org To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/idle, PPC: Remove redundant cpuidle_idle_call() Git-Commit-ID: d8c6ad3184ca6516a5cf457af1afaa293d8f09c0 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.1 (terminus.zytor.com [127.0.0.1]); Tue, 11 Feb 2014 04:18:16 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: d8c6ad3184ca6516a5cf457af1afaa293d8f09c0 Gitweb: http://git.kernel.org/tip/d8c6ad3184ca6516a5cf457af1afaa293d8f09c0 Author: Nicolas Pitre AuthorDate: Wed, 29 Jan 2014 12:45:10 -0500 Committer: Ingo Molnar CommitDate: Tue, 11 Feb 2014 09:58:24 +0100 sched/idle, PPC: Remove redundant cpuidle_idle_call() 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 Cc: "Rafael J. Wysocki" Cc: Daniel Lezcano Cc: linux-arm-kernel@lists.infradead.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-sh@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: Russell King Cc: linaro-kernel@lists.linaro.org Cc: Benjamin Herrenschmidt Cc: Paul Mundt Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/n/tip-47o4m03citrfg9y1vxic5asb@git.kernel.org Signed-off-by: Ingo Molnar --- arch/powerpc/platforms/pseries/setup.c | 34 ++++++++++++++-------------------- drivers/cpuidle/cpuidle-pseries.c | 5 +++++ 2 files changed, 19 insertions(+), 20 deletions(-) diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index 8e639d7..c737d55 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; } /* diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c index 7ab564a..d486489 100644 --- a/drivers/cpuidle/cpuidle-pseries.c +++ b/drivers/cpuidle/cpuidle-pseries.c @@ -29,6 +29,7 @@ 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 @@ -45,6 +46,10 @@ 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,