sched/fair: Encapsulate set custom slice in a __setparam_fair() function

Similarly to dl, create a __setparam_fair() function to set parameters
related to fair class and move it in the fair.c file.

No functional changes expected

Signed-off-by: Vincent Guittot <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Phil Auld <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: vingu-linaro

kernel/sched/fair.c

@@ -37,6 +37,7 @@
 #include <linux/sched/cputime.h>
 #include <linux/sched/isolation.h>
 #include <linux/sched/nohz.h>
+#include <linux/sched/prio.h>
 
 #include <linux/cpuidle.h>
 #include <linux/interrupt.h>
@@ -51,6 +52,8 @@
 
 #include <asm/switch_to.h>
 
+#include <uapi/linux/sched/types.h>
+
 #include "sched.h"
 #include "stats.h"
 #include "autogroup.h"
@@ -5258,6 +5261,22 @@ static inline void update_misfit_status(struct task_struct *p, struct rq *rq) {}
 
 #endif /* CONFIG_SMP */
 
+void __setparam_fair(struct task_struct *p, const struct sched_attr *attr)
+{
+	struct sched_entity *se = &p->se;
+
+	p->static_prio = NICE_TO_PRIO(attr->sched_nice);
+	if (attr->sched_runtime) {
+		se->custom_slice = 1;
+		se->slice = clamp_t(u64, attr->sched_runtime,
+				      NSEC_PER_MSEC/10,   /* HZ=1000 * 10 */
+				      NSEC_PER_MSEC*100); /* HZ=100  / 10 */
+	} else {
+		se->custom_slice = 0;
+		se->slice = sysctl_sched_base_slice;
+	}
+}
+
 static void
 place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 {

kernel/sched/sched.h

@@ -3500,6 +3500,8 @@ unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned
 
 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */
 
+extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr);
+
 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
 
 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))

kernel/sched/syscalls.c

@@ -300,20 +300,10 @@ static void __setscheduler_params(struct task_struct *p,
 
 	p->policy = policy;
 
-	if (dl_policy(policy)) {
+	if (dl_policy(policy))
 		__setparam_dl(p, attr);
-	} else if (fair_policy(policy)) {
-		p->static_prio = NICE_TO_PRIO(attr->sched_nice);
-		if (attr->sched_runtime) {
-			p->se.custom_slice = 1;
-			p->se.slice = clamp_t(u64, attr->sched_runtime,
-					      NSEC_PER_MSEC/10,   /* HZ=1000 * 10 */
-					      NSEC_PER_MSEC*100); /* HZ=100  / 10 */
-		} else {
-			p->se.custom_slice = 0;
-			p->se.slice = sysctl_sched_base_slice;
-		}
-	}
+	else if (fair_policy(policy))
+		__setparam_fair(p, attr);
 
 	/* rt-policy tasks do not have a timerslack */
 	if (rt_or_dl_task_policy(p)) {