Changes from v1
- Enhance commit msg
- Prevent WARN in cpumask_test_cpu() in cpudl_find() when best_cpu == -1
-----8<-----
>From 7735382d07ae6a61d740ae39ba2ecf169d43b8a2 Mon Sep 17 00:00:00 2001
From: Byungchul Park <byungchul.p...@lge.com>
Date: Wed, 22 Mar 2017 14:25:56 +0900
Subject: [RESEND PATCH v2 1/2] sched/deadline: Add cpudl_maximum_dl() for
clean-up
Current code uses cpudl_maximum() to get the root node's cpu, while it
directly accesses the root node like 'cp->elements[0].dl' to get the
root node's dl. It would be more readible to add a function for the dl,
as well. Added it.
Signed-off-by: Byungchul Park <byungchul.p...@lge.com>
Acked-by: Steven Rostedt (VMware) <rost...@goodmis.org>
---
kernel/sched/cpudeadline.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index 8d9562d..9f02035 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -108,11 +108,16 @@ static void cpudl_heapify(struct cpudl *cp, int idx)
cpudl_heapify_down(cp, idx);
}
-static inline int cpudl_maximum(struct cpudl *cp)
+static inline int cpudl_maximum_cpu(struct cpudl *cp)
{
return cp->elements[0].cpu;
}
+static inline u64 cpudl_maximum_dl(struct cpudl *cp)
+{
+ return cp->elements[0].dl;
+}
+
/*
* cpudl_find - find the best (later-dl) CPU in the system
* @cp: the cpudl max-heap context
@@ -130,11 +135,11 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed)) {
return 1;
} else {
- int best_cpu = cpudl_maximum(cp);
+ int best_cpu = cpudl_maximum_cpu(cp);
WARN_ON(best_cpu != -1 && !cpu_present(best_cpu));
if (cpumask_test_cpu(best_cpu, &p->cpus_allowed) &&
- dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
+ dl_time_before(dl_se->deadline, cpudl_maximum_dl(cp))) {
if (later_mask)
cpumask_set_cpu(best_cpu, later_mask);
--
1.9.1
