From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756048AbbDNVQ1 (ORCPT ); Tue, 14 Apr 2015 17:16:27 -0400 Received: from www.linutronix.de ([62.245.132.108]:37932 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755200AbbDNVIT (ORCPT ); Tue, 14 Apr 2015 17:08:19 -0400 Message-Id: <20150414203501.322887675@linutronix.de> User-Agent: quilt/0.63-1 Date: Tue, 14 Apr 2015 21:08:41 -0000 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Preeti U Murthy , Viresh Kumar , Marcelo Tosatti , Frederic Weisbecker Subject: [patch 10/39] hrtimer: Use cpu_base->active_base for hotpath iterators References: <20150414203303.702062272@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=hrtimer-iterate-smarter.patch X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001,URIBL_BLOCKED=0.001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that we have the active_bases field in sync we can use it for iterating over the clock bases. This allows to break out early if no more active clock bases are available and avoids touching the cache lines of inactive clock bases. Signed-off-by: Thomas Gleixner --- kernel/time/hrtimer.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) Index: tip/kernel/time/hrtimer.c =================================================================== --- tip.orig/kernel/time/hrtimer.c +++ tip/kernel/time/hrtimer.c @@ -419,16 +419,16 @@ static ktime_t __hrtimer_get_next_event( { struct hrtimer_clock_base *base = cpu_base->clock_base; ktime_t expires, expires_next = { .tv64 = KTIME_MAX }; - int i; + unsigned int active = cpu_base->active_bases; - for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) { + for (; active; base++, active >>= 1) { struct timerqueue_node *next; struct hrtimer *timer; - next = timerqueue_getnext(&base->active); - if (!next) + if (!(active & 0x01)) continue; + next = timerqueue_getnext(&base->active); timer = container_of(next, struct hrtimer, node); expires = ktime_sub(hrtimer_get_expires(timer), base->offset); if (expires.tv64 < expires_next.tv64) @@ -1206,17 +1206,16 @@ static void __run_hrtimer(struct hrtimer static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now) { - int i; + struct hrtimer_clock_base *base = cpu_base->clock_base; + unsigned int active = cpu_base->active_bases; - for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { - struct hrtimer_clock_base *base; + for (; active; base++, active >>= 1) { struct timerqueue_node *node; ktime_t basenow; - if (!(cpu_base->active_bases & (1 << i))) + if (!(active & 0x01)) continue; - base = cpu_base->clock_base + i; basenow = ktime_add(now, base->offset); while ((node = timerqueue_getnext(&base->active))) {