sched/core: Rename schedutil_cpu_util() and allow rest of the kernel to use it

There is nothing schedutil specific in schedutil_cpu_util(), rename it
to effective_cpu_util(). Also create and expose another wrapper
sched_cpu_util() which can be used by other parts of the kernel, like
thermal core (that will be done in a later commit).

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/db011961fb3bb8bef1c0eda5cd64564637d3ef31.1607400596.git.viresh.kumar@linaro.org

include/linux/sched.h

@@ -1968,6 +1968,11 @@ extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
 #define TASK_SIZE_OF(tsk)	TASK_SIZE
 #endif
 
+#ifdef CONFIG_SMP
+/* Returns effective CPU energy utilization, as seen by the scheduler */
+unsigned long sched_cpu_util(int cpu, unsigned long max);
+#endif /* CONFIG_SMP */
+
 #ifdef CONFIG_RSEQ
 
 /*

kernel/sched/core.c

@@ -5683,8 +5683,8 @@ struct task_struct *idle_task(int cpu)
  * based on the task model parameters and gives the minimal utilization
  * required to meet deadlines.
  */
-unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
+unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
-				 unsigned long max, enum schedutil_type type,
+				 unsigned long max, enum cpu_util_type type,
 				 struct task_struct *p)
 {
 	unsigned long dl_util, util, irq;
@@ -5768,6 +5768,12 @@ unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
 
 	return min(max, util);
 }
+
+unsigned long sched_cpu_util(int cpu, unsigned long max)
+{
+	return effective_cpu_util(cpu, cpu_util_cfs(cpu_rq(cpu)), max,
+				  ENERGY_UTIL, NULL);
+}
 #endif /* CONFIG_SMP */
 
 /**

kernel/sched/cpufreq_schedutil.c

@@ -178,7 +178,7 @@ static void sugov_get_util(struct sugov_cpu *sg_cpu)
 
 	sg_cpu->max = max;
 	sg_cpu->bw_dl = cpu_bw_dl(rq);
-	sg_cpu->util = schedutil_cpu_util(sg_cpu->cpu, cpu_util_cfs(rq), max,
+	sg_cpu->util = effective_cpu_util(sg_cpu->cpu, cpu_util_cfs(rq), max,
 					  FREQUENCY_UTIL, NULL);
 }
 

kernel/sched/fair.c

@@ -6543,7 +6543,7 @@ compute_energy(struct task_struct *p, int dst_cpu, struct perf_domain *pd)
 		 * is already enough to scale the EM reported power
 		 * consumption at the (eventually clamped) cpu_capacity.
 		 */
-		sum_util += schedutil_cpu_util(cpu, util_cfs, cpu_cap,
+		sum_util += effective_cpu_util(cpu, util_cfs, cpu_cap,
 					       ENERGY_UTIL, NULL);
 
 		/*
@@ -6553,7 +6553,7 @@ compute_energy(struct task_struct *p, int dst_cpu, struct perf_domain *pd)
 		 * NOTE: in case RT tasks are running, by default the
 		 * FREQUENCY_UTIL's utilization can be max OPP.
 		 */
-		cpu_util = schedutil_cpu_util(cpu, util_cfs, cpu_cap,
+		cpu_util = effective_cpu_util(cpu, util_cfs, cpu_cap,
 					      FREQUENCY_UTIL, tsk);
 		max_util = max(max_util, cpu_util);
 	}
@@ -6651,7 +6651,7 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
 			 * IOW, placing the task there would make the CPU
 			 * overutilized. Take uclamp into account to see how
 			 * much capacity we can get out of the CPU; this is
-			 * aligned with schedutil_cpu_util().
+			 * aligned with sched_cpu_util().
 			 */
 			util = uclamp_rq_util_with(cpu_rq(cpu), util, p);
 			if (!fits_capacity(util, cpu_cap))

kernel/sched/sched.h

@@ -2559,22 +2559,22 @@ static inline unsigned long capacity_orig_of(int cpu)
 }
 
 /**
- * enum schedutil_type - CPU utilization type
+ * enum cpu_util_type - CPU utilization type
  * @FREQUENCY_UTIL:	Utilization used to select frequency
  * @ENERGY_UTIL:	Utilization used during energy calculation
  *
  * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
  * need to be aggregated differently depending on the usage made of them. This
- * enum is used within schedutil_freq_util() to differentiate the types of
+ * enum is used within effective_cpu_util() to differentiate the types of
  * utilization expected by the callers, and adjust the aggregation accordingly.
  */
-enum schedutil_type {
+enum cpu_util_type {
 	FREQUENCY_UTIL,
 	ENERGY_UTIL,
 };
 
-unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
+unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
-				 unsigned long max, enum schedutil_type type,
+				 unsigned long max, enum cpu_util_type type,
 				 struct task_struct *p);
 
 static inline unsigned long cpu_bw_dl(struct rq *rq)