[PATCH V2 1/2] sched: Factor out nr_iowait and nr_iowait_cpu

From: Daniel Lezcano
Date: Thu Oct 04 2018 - 08:04:16 EST


The function nr_iowait_cpu() can be used directly by nr_iowait() instead
of duplicating code.

Call nr_iowait_cpu() from nr_iowait()

Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
kernel/sched/core.c | 41 ++++++++++++++++++++---------------------
1 file changed, 20 insertions(+), 21 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 625bc98..43efb74 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2875,6 +2875,25 @@ unsigned long long nr_context_switches(void)
}

/*
+ * Consumers of these two interfaces, like for example the cpufreq menu
+ * governor are using nonsensical data. Boosting frequency for a CPU that has
+ * IO-wait which might not even end up running the task when it does become
+ * runnable.
+ */
+
+unsigned long nr_iowait_cpu(int cpu)
+{
+ return atomic_read(&cpu_rq(cpu)->nr_iowait);
+}
+
+void get_iowait_load(unsigned long *nr_waiters, unsigned long *load)
+{
+ struct rq *rq = this_rq();
+ *nr_waiters = atomic_read(&rq->nr_iowait);
+ *load = rq->load.weight;
+}
+
+/*
* IO-wait accounting, and how its mostly bollocks (on SMP).
*
* The idea behind IO-wait account is to account the idle time that we could
@@ -2909,31 +2928,11 @@ unsigned long nr_iowait(void)
unsigned long i, sum = 0;

for_each_possible_cpu(i)
- sum += atomic_read(&cpu_rq(i)->nr_iowait);
+ sum += nr_iowait_cpu(i);

return sum;
}

-/*
- * Consumers of these two interfaces, like for example the cpufreq menu
- * governor are using nonsensical data. Boosting frequency for a CPU that has
- * IO-wait which might not even end up running the task when it does become
- * runnable.
- */
-
-unsigned long nr_iowait_cpu(int cpu)
-{
- struct rq *this = cpu_rq(cpu);
- return atomic_read(&this->nr_iowait);
-}
-
-void get_iowait_load(unsigned long *nr_waiters, unsigned long *load)
-{
- struct rq *rq = this_rq();
- *nr_waiters = atomic_read(&rq->nr_iowait);
- *load = rq->load.weight;
-}
-
#ifdef CONFIG_SMP

/*
--
2.7.4