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From: Parth Shah <parth@linux.ibm.com>
To: linux-kernel@vger.kernel.org
Cc: peterz@infradead.org, mingo@redhat.com,
	vincent.guittot@linaro.org, subhra.mazumdar@oracle.com
Subject: [RFC 1/2] sched/fair: Rename select_idle_mask to iterator_mask
Date: Mon,  8 Jul 2019 10:24:31 +0530	[thread overview]
Message-ID: <20190708045432.18774-2-parth@linux.ibm.com> (raw)
In-Reply-To: <20190708045432.18774-1-parth@linux.ibm.com>

Per cpu variable 'select_idle_mask' serves the only purpose of an iterator
inside select_idle_core method. Also there is an opportunity to optimize
the search for an idle CPU for which this mask is required in the
subsequent patch. Hence renaming this per_cpu variable to iterator mask
which can be used locally for CPU iteration.

Subsequent patch uses the select_idle_mask to keep track of the idle CPUs
which can be shared across function calls.


Signed-off-by: Parth Shah <parth@linux.ibm.com>
---
 kernel/sched/core.c | 4 ++--
 kernel/sched/fair.c | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 4778c48a7fda..d5a6bdc956c8 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5950,7 +5950,7 @@ static struct kmem_cache *task_group_cache __read_mostly;
 #endif
 
 DECLARE_PER_CPU(cpumask_var_t, load_balance_mask);
-DECLARE_PER_CPU(cpumask_var_t, select_idle_mask);
+DECLARE_PER_CPU(cpumask_var_t, iterator_mask);
 
 void __init sched_init(void)
 {
@@ -5989,7 +5989,7 @@ void __init sched_init(void)
 	for_each_possible_cpu(i) {
 		per_cpu(load_balance_mask, i) = (cpumask_var_t)kzalloc_node(
 			cpumask_size(), GFP_KERNEL, cpu_to_node(i));
-		per_cpu(select_idle_mask, i) = (cpumask_var_t)kzalloc_node(
+		per_cpu(iterator_mask, i) = (cpumask_var_t)kzalloc_node(
 			cpumask_size(), GFP_KERNEL, cpu_to_node(i));
 	}
 #endif /* CONFIG_CPUMASK_OFFSTACK */
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index fdab7eb6f351..20affe03379d 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5294,7 +5294,7 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 
 /* Working cpumask for: load_balance, load_balance_newidle. */
 DEFINE_PER_CPU(cpumask_var_t, load_balance_mask);
-DEFINE_PER_CPU(cpumask_var_t, select_idle_mask);
+DEFINE_PER_CPU(cpumask_var_t, iterator_mask);
 
 #ifdef CONFIG_NO_HZ_COMMON
 /*
@@ -6083,7 +6083,7 @@ void __update_idle_core(struct rq *rq)
  */
 static int select_idle_core(struct task_struct *p, struct sched_domain *sd, int target)
 {
-	struct cpumask *cpus = this_cpu_cpumask_var_ptr(select_idle_mask);
+	struct cpumask *cpus = this_cpu_cpumask_var_ptr(iterator_mask);
 	int core, cpu;
 
 	if (!static_branch_likely(&sched_smt_present))
-- 
2.17.1


  reply	other threads:[~2019-07-08  4:54 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-08  4:54 [RFC 0/2] Optimize the idle CPU search Parth Shah
2019-07-08  4:54 ` Parth Shah [this message]
2019-07-08  4:54 ` [RFC 2/2] sched/fair: " Parth Shah
2019-07-08  8:08 ` [RFC 0/2] " Peter Zijlstra
2019-07-08  9:09   ` Parth Shah
2019-07-09  6:45   ` Subhra Mazumdar
2019-07-09  0:08 ` Subhra Mazumdar
2019-07-09  5:38   ` Parth Shah
2019-07-09  6:48     ` Subhra Mazumdar

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