[tip:sched/core] sched/fair: Use 'unsigned long' for utilization, consistently

From: tip-bot for Patrick Bellasi
Date: Wed Jan 10 2018 - 07:19:13 EST


Commit-ID: f01415fdbfe83380c2dfcf90b7b26042f88963aa
Gitweb: https://git.kernel.org/tip/f01415fdbfe83380c2dfcf90b7b26042f88963aa
Author: Patrick Bellasi <patrick.bellasi@xxxxxxx>
AuthorDate: Tue, 5 Dec 2017 17:10:15 +0000
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 10 Jan 2018 11:30:28 +0100

sched/fair: Use 'unsigned long' for utilization, consistently

Utilization and capacity are tracked as 'unsigned long', however some
functions using them return an 'int' which is ultimately assigned back to
'unsigned long' variables.

Since there is not scope on using a different and signed type,
consolidate the signature of functions returning utilization to always
use the native type.

This change improves code consistency, and it also benefits
code paths where utilizations should be clamped by avoiding
further type conversions or ugly type casts.

Signed-off-by: Patrick Bellasi <patrick.bellasi@xxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Chris Redpath <chris.redpath@xxxxxxx>
Reviewed-by: Brendan Jackman <brendan.jackman@xxxxxxx>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
Cc: Joel Fernandes <joelaf@xxxxxxxxxx>
Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Morten Rasmussen <morten.rasmussen@xxxxxxx>
Cc: Paul Turner <pjt@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rafael J . Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Todd Kjos <tkjos@xxxxxxxxxxx>
Cc: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20171205171018.9203-2-patrick.bellasi@xxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
kernel/sched/fair.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 2915c0d..de43bd8 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5765,8 +5765,8 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p,
return affine;
}

-static inline int task_util(struct task_struct *p);
-static int cpu_util_wake(int cpu, struct task_struct *p);
+static inline unsigned long task_util(struct task_struct *p);
+static unsigned long cpu_util_wake(int cpu, struct task_struct *p);

static unsigned long capacity_spare_wake(int cpu, struct task_struct *p)
{
@@ -6247,7 +6247,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target)
* capacity_orig) as it useful for predicting the capacity required after task
* migrations (scheduler-driven DVFS).
*/
-static int cpu_util(int cpu)
+static unsigned long cpu_util(int cpu)
{
unsigned long util = cpu_rq(cpu)->cfs.avg.util_avg;
unsigned long capacity = capacity_orig_of(cpu);
@@ -6255,7 +6255,7 @@ static int cpu_util(int cpu)
return (util >= capacity) ? capacity : util;
}

-static inline int task_util(struct task_struct *p)
+static inline unsigned long task_util(struct task_struct *p)
{
return p->se.avg.util_avg;
}
@@ -6264,7 +6264,7 @@ static inline int task_util(struct task_struct *p)
* cpu_util_wake: Compute cpu utilization with any contributions from
* the waking task p removed.
*/
-static int cpu_util_wake(int cpu, struct task_struct *p)
+static unsigned long cpu_util_wake(int cpu, struct task_struct *p)
{
unsigned long util, capacity;