[tip:sched/core] sched/cpufreq: Move arch_scale_{freq,cpu}_capacity() outside of #ifdef CONFIG_SMP

[tip-bot for Juri Lelli]

Commit-ID:  7e1a9208f6c7e66bb4e5d2ed18dfd191230f431b
Gitweb:     https://git.kernel.org/tip/7e1a9208f6c7e66bb4e5d2ed18dfd191230f431b
Author:     Juri Lelli <juri.lelli@xxxxxxx>
AuthorDate: Mon, 4 Dec 2017 11:23:24 +0100
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 10 Jan 2018 12:53:35 +0100

sched/cpufreq: Move arch_scale_{freq,cpu}_capacity() outside of #ifdef CONFIG_SMP

Currently, frequency and cpu capacity scaling is only performed on
CONFIG_SMP systems (as CFS PELT signals are only present for such
systems). However, other scheduling classes want to do freq/cpu scaling,
and for !CONFIG_SMP configurations as well.

arch_scale_freq_capacity() is useful to implement frequency scaling even
on !CONFIG_SMP platforms, so we simply move it outside CONFIG_SMP
ifdeffery.

Even if arch_scale_cpu_capacity() is not useful on !CONFIG_SMP platforms,
we make a default implementation available for such configurations anyway
to simplify scheduler code doing CPU scale invariance.

Signed-off-by: Juri Lelli <juri.lelli@xxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: alessio.balsini@xxxxxxx
Cc: bristot@xxxxxxxxxx
Cc: claudio@xxxxxxxxxxxxxxx
Cc: dietmar.eggemann@xxxxxxx
Cc: joelaf@xxxxxxxxxx
Cc: juri.lelli@xxxxxxxxxx
Cc: luca.abeni@xxxxxxxxxxxxxxx
Cc: mathieu.poirier@xxxxxxxxxx
Cc: morten.rasmussen@xxxxxxx
Cc: patrick.bellasi@xxxxxxx
Cc: rjw@xxxxxxxxxxxxx
Cc: tkjos@xxxxxxxxxxx
Cc: tommaso.cucinotta@xxxxxxxxxxxxxxx
Cc: vincent.guittot@xxxxxxxxxx
Cc: viresh.kumar@xxxxxxxxxx
Link: http://lkml.kernel.org/r/20171204102325.5110-8-juri.lelli@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 include/linux/sched/topology.h | 12 ++++++------
 kernel/sched/sched.h           | 13 ++++++++++---
 2 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
index cf257c2..2634774 100644
--- a/include/linux/sched/topology.h
+++ b/include/linux/sched/topology.h
@@ -7,6 +7,12 @@
 #include <linux/sched/idle.h>
 
 /*
+ * Increase resolution of cpu_capacity calculations
+ */
+#define SCHED_CAPACITY_SHIFT	SCHED_FIXEDPOINT_SHIFT
+#define SCHED_CAPACITY_SCALE	(1L << SCHED_CAPACITY_SHIFT)
+
+/*
  * sched-domains (multiprocessor balancing) declarations:
  */
 #ifdef CONFIG_SMP
@@ -27,12 +33,6 @@
 #define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
 #define SD_NUMA			0x4000	/* cross-node balancing */
 
-/*
- * Increase resolution of cpu_capacity calculations
- */
-#define SCHED_CAPACITY_SHIFT	SCHED_FIXEDPOINT_SHIFT
-#define SCHED_CAPACITY_SCALE	(1L << SCHED_CAPACITY_SHIFT)
-
 #ifdef CONFIG_SCHED_SMT
 static inline int cpu_smt_flags(void)
 {
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index b710019..e122c89 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1670,9 +1670,6 @@ static inline int hrtick_enabled(struct rq *rq)
 
 #endif /* CONFIG_SCHED_HRTICK */
 
-#ifdef CONFIG_SMP
-extern void sched_avg_update(struct rq *rq);
-
 #ifndef arch_scale_freq_capacity
 static __always_inline
 unsigned long arch_scale_freq_capacity(int cpu)
@@ -1681,6 +1678,9 @@ unsigned long arch_scale_freq_capacity(int cpu)
 }
 #endif
 
+#ifdef CONFIG_SMP
+extern void sched_avg_update(struct rq *rq);
+
 #ifndef arch_scale_cpu_capacity
 static __always_inline
 unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
@@ -1698,6 +1698,13 @@ static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
 	sched_avg_update(rq);
 }
 #else
+#ifndef arch_scale_cpu_capacity
+static __always_inline
+unsigned long arch_scale_cpu_capacity(void __always_unused *sd, int cpu)
+{
+	return SCHED_CAPACITY_SCALE;
+}
+#endif
 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
 static inline void sched_avg_update(struct rq *rq) { }
 #endif