[PATCH] sched/fair: Introduce fits_capacity()

[Viresh Kumar]

The same formula to check utilization against capacity (after
considering capacity_margin) is already used at 5 different locations.

This patch creates a new macro, fits_capacity(), which can be used from
all these locations without exposing the details of it and hence
simplify code.

All the 5 code locations are updated as well to use it..

Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
---
 kernel/sched/fair.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 7f8d477f90fe..db3a218b7928 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -102,6 +102,8 @@ int __weak arch_asym_cpu_priority(int cpu)
  * (default: ~20%)
  */
 static unsigned int capacity_margin                    = 1280;
+
+#define fits_capacity(cap, max)        ((cap) * capacity_margin < (max) * 1024)
 #endif
 
 #ifdef CONFIG_CFS_BANDWIDTH
@@ -3727,7 +3729,7 @@ util_est_dequeue(struct cfs_rq *cfs_rq, struct 
task_struct *p, bool task_sleep)
 
 static inline int task_fits_capacity(struct task_struct *p, long capacity)
 {
-       return capacity * 1024 > task_util_est(p) * capacity_margin;
+       return fits_capacity(task_util_est(p), capacity);
 }
 
 static inline void update_misfit_status(struct task_struct *p, struct rq *rq)
@@ -5143,7 +5145,7 @@ static inline unsigned long cpu_util(int cpu);
 
 static inline bool cpu_overutilized(int cpu)
 {
-       return (capacity_of(cpu) * 1024) < (cpu_util(cpu) * capacity_margin);
+       return !fits_capacity(cpu_util(cpu), capacity_of(cpu));
 }
 
 static inline void update_overutilized_status(struct rq *rq)
@@ -6304,7 +6306,7 @@ static int find_energy_efficient_cpu(struct task_struct 
*p, int prev_cpu)
                        /* Skip CPUs that will be overutilized. */
                        util = cpu_util_next(cpu, p, cpu);
                        cpu_cap = capacity_of(cpu);
-                       if (cpu_cap * 1024 < util * capacity_margin)
+                       if (!fits_capacity(util, cpu_cap))
                                continue;
 
                        /* Always use prev_cpu as a candidate. */
@@ -7853,8 +7855,7 @@ group_is_overloaded(struct lb_env *env, struct 
sg_lb_stats *sgs)
 static inline bool
 group_smaller_min_cpu_capacity(struct sched_group *sg, struct sched_group *ref)
 {
-       return sg->sgc->min_capacity * capacity_margin <
-                                               ref->sgc->min_capacity * 1024;
+       return fits_capacity(sg->sgc->min_capacity, ref->sgc->min_capacity);
 }
 
 /*
@@ -7864,8 +7865,7 @@ group_smaller_min_cpu_capacity(struct sched_group *sg, 
struct sched_group *ref)
 static inline bool
 group_smaller_max_cpu_capacity(struct sched_group *sg, struct sched_group *ref)
 {
-       return sg->sgc->max_capacity * capacity_margin <
-                                               ref->sgc->max_capacity * 1024;
+       return fits_capacity(sg->sgc->max_capacity, ref->sgc->max_capacity);
 }
 
 static inline enum
-- 
2.21.0.rc0.269.g1a574e7a288b