From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752688AbbGOQmz (ORCPT ); Wed, 15 Jul 2015 12:42:55 -0400 Received: from e28smtp08.in.ibm.com ([122.248.162.8]:47357 "EHLO e28smtp08.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751738AbbGOQmx (ORCPT ); Wed, 15 Jul 2015 12:42:53 -0400 X-Helo: d28dlp02.in.ibm.com X-MailFrom: srikar@linux.vnet.ibm.com X-RcptTo: linux-kernel@vger.kernel.org From: Srikar Dronamraju To: Ingo Molnar , Peter Zijlstra Cc: linux-kernel@vger.kernel.org, srikar@linux.vnet.ibm.com, Rik van Riel , Mel Gorman Subject: [PATCH] sched/numa: Disable sched_numa_balancing on uma systems Date: Wed, 15 Jul 2015 22:12:37 +0530 Message-Id: <1436978557-24935-1-git-send-email-srikar@linux.vnet.ibm.com> X-Mailer: git-send-email 2.1.4 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15071516-0029-0000-0000-000006F33905 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 2a1ed24 ("sched/numa: Prefer NUMA hotness over cache hotness") sets sched feature NUMA to true. However this can enable numa hinting faults on a uma system. This commit ensures that numa hinting faults occur only on a numa system by setting/resetting sched_numa_balancing. This commit - Renames numabalancing_enabled to sched_numa_balancing - Makes sched_numa_balancing common to CONFIG_SCHED_DEBUG and !CONFIG_SCHED_DEBUG. Earlier it was only in !CONFIG_SCHED_DEBUG - Checks for sched_numa_balancing instead of sched_feat(NUMA) Signed-off-by: Srikar Dronamraju --- kernel/sched/core.c | 16 ++++++---------- kernel/sched/fair.c | 8 ++++---- kernel/sched/sched.h | 10 ++-------- 3 files changed, 12 insertions(+), 22 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 78b4bad10..4722f5c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2059,22 +2059,18 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p) } #ifdef CONFIG_NUMA_BALANCING -#ifdef CONFIG_SCHED_DEBUG +__read_mostly bool sched_numa_balancing; + void set_numabalancing_state(bool enabled) { + sched_numa_balancing = enabled; +#ifdef CONFIG_SCHED_DEBUG if (enabled) sched_feat_set("NUMA"); else sched_feat_set("NO_NUMA"); -} -#else -__read_mostly bool numabalancing_enabled; - -void set_numabalancing_state(bool enabled) -{ - numabalancing_enabled = enabled; -} #endif /* CONFIG_SCHED_DEBUG */ +} #ifdef CONFIG_PROC_SYSCTL int sysctl_numa_balancing(struct ctl_table *table, int write, @@ -2082,7 +2078,7 @@ int sysctl_numa_balancing(struct ctl_table *table, int write, { struct ctl_table t; int err; - int state = numabalancing_enabled; + int state = sched_numa_balancing; if (write && !capable(CAP_SYS_ADMIN)) return -EPERM; diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 587a2f6..5a901fd 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2059,7 +2059,7 @@ void task_numa_fault(int last_cpupid, int mem_node, int pages, int flags) int local = !!(flags & TNF_FAULT_LOCAL); int priv; - if (!numabalancing_enabled) + if (!sched_numa_balancing) return; /* for example, ksmd faulting in a user's mm */ @@ -5676,10 +5676,10 @@ static int migrate_degrades_locality(struct task_struct *p, struct lb_env *env) unsigned long src_faults, dst_faults; int src_nid, dst_nid; - if (!p->numa_faults || !(env->sd->flags & SD_NUMA)) + if (!sched_numa_balancing) return -1; - if (!sched_feat(NUMA)) + if (!p->numa_faults || !(env->sd->flags & SD_NUMA)) return -1; src_nid = cpu_to_node(env->src_cpu); @@ -7980,7 +7980,7 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued) entity_tick(cfs_rq, se, queued); } - if (numabalancing_enabled) + if (sched_numa_balancing) task_tick_numa(rq, curr); update_rq_runnable_avg(rq, 1); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 84d4879..93d8c17 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1014,15 +1014,9 @@ extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */ #ifdef CONFIG_NUMA_BALANCING -#define sched_feat_numa(x) sched_feat(x) -#ifdef CONFIG_SCHED_DEBUG -#define numabalancing_enabled sched_feat_numa(NUMA) -#else -extern bool numabalancing_enabled; -#endif /* CONFIG_SCHED_DEBUG */ +extern bool sched_numa_balancing; #else -#define sched_feat_numa(x) (0) -#define numabalancing_enabled (0) +#define sched_numa_balancing (0) #endif /* CONFIG_NUMA_BALANCING */ static inline u64 global_rt_period(void) -- 1.8.3.1