From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755888Ab3E0Jqi (ORCPT ); Mon, 27 May 2013 05:46:38 -0400 Received: from terminus.zytor.com ([198.137.202.10]:35340 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755520Ab3E0Jqh (ORCPT ); Mon, 27 May 2013 05:46:37 -0400 Date: Mon, 27 May 2013 02:46:22 -0700 From: tip-bot for Thomas Gleixner Message-ID: Cc: linux-kernel@vger.kernel.org, john.stultz@linaro.org, hpa@zytor.com, mingo@kernel.org, tglx@linutronix.de, magnus.damm@gmail.com Reply-To: mingo@kernel.org, hpa@zytor.com, john.stultz@linaro.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, magnus.damm@gmail.com In-Reply-To: <20130425143435.834965397@linutronix.de> References: <20130425143435.834965397@linutronix.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:timers/core] clocksource: Allow clocksource select to skip current clocksource Git-Commit-ID: f5a2e34375a5e2b711aea488ac3ae50eeba6d57c 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: f5a2e34375a5e2b711aea488ac3ae50eeba6d57c Gitweb: http://git.kernel.org/tip/f5a2e34375a5e2b711aea488ac3ae50eeba6d57c Author: Thomas Gleixner AuthorDate: Thu, 25 Apr 2013 20:31:45 +0000 Committer: Thomas Gleixner CommitDate: Thu, 16 May 2013 11:09:15 +0200 clocksource: Allow clocksource select to skip current clocksource Preparatory patch for clocksource unbind support. Split out code from clocksource_select and modify it, so it skips the current clocksource on request and tries to find a fallback clocksource. Convert all existing users. No functional change. Signed-off-by: Thomas Gleixner Cc: John Stultz Cc: Magnus Damm Link: http://lkml.kernel.org/r/20130425143435.834965397@linutronix.de Signed-off-by: Thomas Gleixner --- kernel/time/clocksource.c | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 1923a34..9782997 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -553,7 +553,7 @@ static u64 clocksource_max_deferment(struct clocksource *cs) #ifndef CONFIG_ARCH_USES_GETTIMEOFFSET -static struct clocksource *clocksource_find_best(bool oneshot) +static struct clocksource *clocksource_find_best(bool oneshot, bool skipcur) { struct clocksource *cs; @@ -566,6 +566,8 @@ static struct clocksource *clocksource_find_best(bool oneshot) * the best rating. */ list_for_each_entry(cs, &clocksource_list, list) { + if (skipcur && cs == curr_clocksource) + continue; if (oneshot && !(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES)) continue; return cs; @@ -573,26 +575,20 @@ static struct clocksource *clocksource_find_best(bool oneshot) return NULL; } -/** - * clocksource_select - Select the best clocksource available - * - * Private function. Must hold clocksource_mutex when called. - * - * Select the clocksource with the best rating, or the clocksource, - * which is selected by userspace override. - */ -static void clocksource_select(void) +static void __clocksource_select(bool skipcur) { bool oneshot = tick_oneshot_mode_active(); struct clocksource *best, *cs; /* Find the best suitable clocksource */ - best = clocksource_find_best(oneshot); + best = clocksource_find_best(oneshot, skipcur); if (!best) return; /* Check for the override clocksource. */ list_for_each_entry(cs, &clocksource_list, list) { + if (skipcur && cs == curr_clocksource) + continue; if (strcmp(cs->name, override_name) != 0) continue; /* @@ -618,6 +614,19 @@ static void clocksource_select(void) } } +/** + * clocksource_select - Select the best clocksource available + * + * Private function. Must hold clocksource_mutex when called. + * + * Select the clocksource with the best rating, or the clocksource, + * which is selected by userspace override. + */ +static void clocksource_select(void) +{ + return __clocksource_select(false); +} + #else /* !CONFIG_ARCH_USES_GETTIMEOFFSET */ static inline void clocksource_select(void) { }