Commit-ID: 2e62c4743adc4c7bfcbc1f45118fc7bec58cf30a
Gitweb: https://git.kernel.org/tip/2e62c4743adc4c7bfcbc1f45118fc7bec58cf30a
Author: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
AuthorDate: Thu, 19 Jul 2018 14:00:06 +0200
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 25 Jul 2018 11:41:05 +0200
sched/fair: Remove #ifdefs from scale_rt_capacity()
Reuse cpu_util_irq() that has been defined for schedutil and set irq util
to 0 when !CONFIG_IRQ_TIME_ACCOUNTING.
But the compiler is not able to optimize the sequence (at least with
aarch64 GCC 7.2.1):
free *= (max - irq);
free /= max;
when irq is fixed to 0
Add a new inline function scale_irq_capacity() that will scale utilization
when irq is accounted. Reuse this funciton in schedutil which applies
similar formula.
Suggested-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: rjw@xxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/1532001606-6689-1-git-send-email-vincent.guittot@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
kernel/sched/core.c | 2 +-
kernel/sched/cpufreq_schedutil.c | 3 +--
kernel/sched/fair.c | 13 +++----------
kernel/sched/sched.h | 20 ++++++++++++++++++--
4 files changed, 23 insertions(+), 15 deletions(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c3cf7d992159..fc177c06e490 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -177,7 +177,7 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
rq->clock_task += delta;
-#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
+#ifdef HAVE_SCHED_AVG_IRQ
if ((irq_delta + steal) && sched_feat(NONTASK_CAPACITY))
update_irq_load_avg(rq, irq_delta + steal);
#endif
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 97dcd4472a0e..3fffad3bc8a8 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -247,8 +247,7 @@ static unsigned long sugov_get_util(struct sugov_cpu *sg_cpu)
* U' = irq + ------- * U
* max
*/
- util *= (max - irq);
- util /= max;
+ util = scale_irq_capacity(util, irq, max);
util += irq;
/*
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index d5f7d521e448..14c3fddf822a 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7551,16 +7551,12 @@ static unsigned long scale_rt_capacity(int cpu)
struct rq *rq = cpu_rq(cpu);
unsigned long max = arch_scale_cpu_capacity(NULL, cpu);
unsigned long used, free;
-#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
unsigned long irq;
-#endif
-#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
- irq = READ_ONCE(rq->avg_irq.util_avg);
+ irq = cpu_util_irq(rq);
if (unlikely(irq >= max))
return 1;
-#endif
used = READ_ONCE(rq->avg_rt.util_avg);
used += READ_ONCE(rq->avg_dl.util_avg);
@@ -7569,11 +7565,8 @@ static unsigned long scale_rt_capacity(int cpu)
return 1;
free = max - used;
-#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
- free *= (max - irq);
- free /= max;
-#endif
- return free;
+
+ return scale_irq_capacity(free, irq, max);
}
static void update_cpu_capacity(struct sched_domain *sd, int cpu)
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index ebb4b3c3ece7..614170d9b1aa 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -856,6 +856,7 @@ struct rq {
struct sched_avg avg_rt;
struct sched_avg avg_dl;
#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
+#define HAVE_SCHED_AVG_IRQ
struct sched_avg avg_irq;
#endif
u64 idle_stamp;
@@ -2210,17 +2211,32 @@ static inline unsigned long cpu_util_rt(struct rq *rq)
{
return READ_ONCE(rq->avg_rt.util_avg);
}
+#endif
-#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
+#ifdef HAVE_SCHED_AVG_IRQ
static inline unsigned long cpu_util_irq(struct rq *rq)
{
return rq->avg_irq.util_avg;
}
+
+static inline
+unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
+{
+ util *= (max - irq);
+ util /= max;
+
+ return util;
+
+}
#else
static inline unsigned long cpu_util_irq(struct rq *rq)
{
return 0;
}
-#endif
+static inline
+unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
+{
+ return util;
+}
#endif
--
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