From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753219Ab0ADJT2 (ORCPT ); Mon, 4 Jan 2010 04:19:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752934Ab0ADJT2 (ORCPT ); Mon, 4 Jan 2010 04:19:28 -0500 Received: from mga03.intel.com ([143.182.124.21]:20105 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752923Ab0ADJT1 (ORCPT ); Mon, 4 Jan 2010 04:19:27 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.47,316,1257148800"; d="scan'208";a="228874916" Subject: [RFC PATCH] sched: Pass affine target cpu into wake_affine From: Lin Ming To: Mike Galbraith , Peter Zijlstra Cc: lkml , "Zhang, Yanmin" Content-Type: text/plain Date: Mon, 04 Jan 2010 17:03:47 +0800 Message-Id: <1262595827.22471.108.camel@minggr.sh.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1 (2.24.1-2.fc10) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org commit a03ecf08d7bbdd979d81163ea13d194fe21ad339 Author: Lin Ming Date: Mon Jan 4 14:14:50 2010 +0800 sched: Pass affine target cpu into wake_affine Since commit a1f84a3(sched: Check for an idle shared cache in select_task_rq_fair()), the affine target maybe adjusted to any idle cpu in cache sharing domains instead of current cpu. But wake_affine still use current cpu to calculate load which is wrong. This patch passes affine cpu into wake_affine. Signed-off-by: Lin Ming --- kernel/sched_fair.c | 29 ++++++++++++++--------------- 1 files changed, 14 insertions(+), 15 deletions(-) diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 42ac3c9..0a6fa39 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -1237,11 +1237,11 @@ static inline unsigned long effective_load(struct task_group *tg, int cpu, #endif -static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) +static int wake_affine(struct sched_domain *sd, struct task_struct *p, int affine_cpu, int sync) { struct task_struct *curr = current; - unsigned long this_load, load; - int idx, this_cpu, prev_cpu; + unsigned long affine_load, load; + int idx, prev_cpu; unsigned long tl_per_task; unsigned int imbalance; struct task_group *tg; @@ -1249,10 +1249,9 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) int balanced; idx = sd->wake_idx; - this_cpu = smp_processor_id(); prev_cpu = task_cpu(p); load = source_load(prev_cpu, idx); - this_load = target_load(this_cpu, idx); + affine_load = target_load(affine_cpu, idx); if (sync) { if (sched_feat(SYNC_LESS) && @@ -1275,7 +1274,7 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) tg = task_group(current); weight = current->se.load.weight; - this_load += effective_load(tg, this_cpu, -weight, -weight); + affine_load += effective_load(tg, affine_cpu, -weight, -weight); load += effective_load(tg, prev_cpu, 0, -weight); } @@ -1285,16 +1284,16 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) imbalance = 100 + (sd->imbalance_pct - 100) / 2; /* - * In low-load situations, where prev_cpu is idle and this_cpu is idle - * due to the sync cause above having dropped this_load to 0, we'll + * In low-load situations, where prev_cpu is idle and affine_cpu is idle + * due to the sync cause above having dropped affine_load to 0, we'll * always have an imbalance, but there's really nothing you can do * about that, so that's good too. * * Otherwise check if either cpus are near enough in load to allow this - * task to be woken on this_cpu. + * task to be woken on affine_cpu. */ - balanced = !this_load || - 100*(this_load + effective_load(tg, this_cpu, weight, weight)) <= + balanced = !affine_load || + 100*(affine_load + effective_load(tg, affine_cpu, weight, weight)) <= imbalance*(load + effective_load(tg, prev_cpu, 0, weight)); /* @@ -1306,11 +1305,11 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) return 1; schedstat_inc(p, se.nr_wakeups_affine_attempts); - tl_per_task = cpu_avg_load_per_task(this_cpu); + tl_per_task = cpu_avg_load_per_task(affine_cpu); if (balanced || - (this_load <= load && - this_load + target_load(prev_cpu, idx) <= tl_per_task)) { + (affine_load <= load && + affine_load + target_load(prev_cpu, idx) <= tl_per_task)) { /* * This domain has SD_WAKE_AFFINE and * p is cache cold in this domain, and @@ -1544,7 +1543,7 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag update_shares(tmp); } - if (affine_sd && wake_affine(affine_sd, p, sync)) + if (affine_sd && wake_affine(affine_sd, p, cpu, sync)) return cpu; while (sd) {