Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758033AbZCYJNv (ORCPT ); Wed, 25 Mar 2009 05:13:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751616AbZCYJNn (ORCPT ); Wed, 25 Mar 2009 05:13:43 -0400 Received: from e28smtp07.in.ibm.com ([59.145.155.7]:58530 "EHLO e28smtp07.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751420AbZCYJNl (ORCPT ); Wed, 25 Mar 2009 05:13:41 -0400 From: Gautham R Shenoy Subject: [RFC PATCH 01/11] sched: Simple helper functions for find_busiest_group() To: "Ingo Molnar" , Peter Zijlstra , "Vaidyanathan Srinivasan" Cc: linux-kernel@vger.kernel.org, Suresh Siddha , "Balbir Singh" , Nick Piggin , "Dhaval Giani" , Bharata B Rao , Gautham R Shenoy Date: Wed, 25 Mar 2009 14:43:35 +0530 Message-ID: <20090325091335.13992.55424.stgit@sofia.in.ibm.com> In-Reply-To: <20090325091239.13992.96090.stgit@sofia.in.ibm.com> References: <20090325091239.13992.96090.stgit@sofia.in.ibm.com> User-Agent: StGIT/0.14.2 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4018 Lines: 121 Currently the load idx calculation code is in find_busiest_group(). Move that to a static inline helper function. Similary, to find the first cpu of a sched_group we use cpumask_first(sched_group_cpus(group)) Use a helper to that. It improves readability in some cases. Signed-off-by: Gautham R Shenoy --- kernel/sched.c | 55 +++++++++++++++++++++++++++++++++++++++++++------------ 1 files changed, 43 insertions(+), 12 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index 8e2558c..0b65f8c 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -3085,6 +3085,43 @@ static int move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest, return 0; } +/********** Helpers for find_busiest_group ************************/ + +/** + * group_first_cpu - Returns the first cpu in the cpumask of a sched_group. + * @group: The group whose first cpu is to be returned. + */ +static inline unsigned int group_first_cpu(struct sched_group *group) +{ + return cpumask_first(sched_group_cpus(group)); +} + +/** + * get_sd_load_idx - Obtain the load index for a given sched domain. + * @sd: The sched_domain whose load_idx is to be obtained. + * @idle: The Idle status of the CPU for whose sd load_icx is obtained. + */ +static inline int get_sd_load_idx(struct sched_domain *sd, + enum cpu_idle_type idle) +{ + int load_idx; + + switch (idle) { + case CPU_NOT_IDLE: + load_idx = sd->busy_idx; + break; + + case CPU_NEWLY_IDLE: + load_idx = sd->newidle_idx; + break; + default: + load_idx = sd->idle_idx; + break; + } + + return load_idx; +} +/******* find_busiest_group() helpers end here *********************/ /* * find_busiest_group finds and returns the busiest CPU group within the @@ -3113,12 +3150,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, busiest_load_per_task = busiest_nr_running = 0; this_load_per_task = this_nr_running = 0; - if (idle == CPU_NOT_IDLE) - load_idx = sd->busy_idx; - else if (idle == CPU_NEWLY_IDLE) - load_idx = sd->newidle_idx; - else - load_idx = sd->idle_idx; + load_idx = get_sd_load_idx(sd, idle); do { unsigned long load, group_capacity, max_cpu_load, min_cpu_load; @@ -3134,7 +3166,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, sched_group_cpus(group)); if (local_group) - balance_cpu = cpumask_first(sched_group_cpus(group)); + balance_cpu = group_first_cpu(group); /* Tally up the load of all CPUs in the group */ sum_weighted_load = sum_nr_running = avg_load = 0; @@ -3255,8 +3287,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, */ if ((sum_nr_running < min_nr_running) || (sum_nr_running == min_nr_running && - cpumask_first(sched_group_cpus(group)) > - cpumask_first(sched_group_cpus(group_min)))) { + group_first_cpu(group) > group_first_cpu(group_min))) { group_min = group; min_nr_running = sum_nr_running; min_load_per_task = sum_weighted_load / @@ -3271,8 +3302,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, if (sum_nr_running <= group_capacity - 1) { if (sum_nr_running > leader_nr_running || (sum_nr_running == leader_nr_running && - cpumask_first(sched_group_cpus(group)) < - cpumask_first(sched_group_cpus(group_leader)))) { + group_first_cpu(group) < + group_first_cpu(group_leader))) { group_leader = group; leader_nr_running = sum_nr_running; } @@ -3400,7 +3431,7 @@ out_balanced: *imbalance = min_load_per_task; if (sched_mc_power_savings >= POWERSAVINGS_BALANCE_WAKEUP) { cpu_rq(this_cpu)->rd->sched_mc_preferred_wakeup_cpu = - cpumask_first(sched_group_cpus(group_leader)); + group_first_cpu(group_leader); } return group_min; } -- 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/