Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756019AbZJVMoM (ORCPT ); Thu, 22 Oct 2009 08:44:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755847AbZJVMoK (ORCPT ); Thu, 22 Oct 2009 08:44:10 -0400 Received: from e4.ny.us.ibm.com ([32.97.182.144]:46282 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755075AbZJVMlK (ORCPT ); Thu, 22 Oct 2009 08:41:10 -0400 Message-Id: <20091022124110.600098573@spinlock.in.ibm.com> References: <20091022123743.506956796@spinlock.in.ibm.com> User-Agent: quilt/0.44-1 Date: Thu, 22 Oct 2009 18:07:48 +0530 From: dino@in.ibm.com To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra Cc: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, John Stultz , Darren Hart , John Kacur Subject: [patch -rt 05/17] sched: dynamic cpu_power Content-Disposition: inline; filename=sched-lb-4.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2298 Lines: 76 Recompute the cpu_power for each cpu during load-balance Signed-off-by: Peter Zijlstra Signed-off-by: Dinakar Guniguntala --- kernel/sched.c | 38 +++++++++++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) Index: linux-2.6.31.4-rt14/kernel/sched.c =================================================================== --- linux-2.6.31.4-rt14.orig/kernel/sched.c 2009-10-16 09:15:34.000000000 -0400 +++ linux-2.6.31.4-rt14/kernel/sched.c 2009-10-16 09:15:35.000000000 -0400 @@ -3780,14 +3780,46 @@ } #endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */ -static void update_sched_power(struct sched_domain *sd) +unsigned long __weak arch_smt_gain(struct sched_domain *sd, int cpu) +{ + unsigned long weight = cpumask_weight(sched_domain_span(sd)); + unsigned long smt_gain = sd->smt_gain; + + smt_gain /= weight; + + return smt_gain; +} + +static void update_cpu_power(struct sched_domain *sd, int cpu) +{ + unsigned long weight = cpumask_weight(sched_domain_span(sd)); + unsigned long power = SCHED_LOAD_SCALE; + struct sched_group *sdg = sd->groups; + unsigned long old = sdg->__cpu_power; + + /* here we could scale based on cpufreq */ + + if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) { + power *= arch_smt_gain(sd, cpu); + power >>= SCHED_LOAD_SHIFT; + } + + /* here we could scale based on RT time */ + + if (power != old) { + sdg->__cpu_power = power; + sdg->reciprocal_cpu_power = reciprocal_value(power); + } +} + +static void update_group_power(struct sched_domain *sd, int cpu) { struct sched_domain *child = sd->child; struct sched_group *group, *sdg = sd->groups; unsigned long power = sdg->__cpu_power; if (!child) { - /* compute cpu power for this cpu */ + update_cpu_power(sd, cpu); return; } @@ -3830,7 +3862,7 @@ if (local_group) { balance_cpu = group_first_cpu(group); if (balance_cpu == this_cpu) - update_sched_power(sd); + update_group_power(sd, this_cpu); } /* Tally up the load of all CPUs in the group */ -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/