sched: cleanup, sched_granularity -> sched_min_granularity

due to adaptive granularity scheduling the role of sched_granularity
has changed to "minimum granularity", so rename the variable (and the
tunable) accordingly.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>

include/linux/sched.h

@@ -1400,7 +1400,7 @@ static inline void idle_task_exit(void) {}
 extern void sched_idle_next(void);
 
 extern unsigned int sysctl_sched_latency;
-extern unsigned int sysctl_sched_granularity;
+extern unsigned int sysctl_sched_min_granularity;
 extern unsigned int sysctl_sched_wakeup_granularity;
 extern unsigned int sysctl_sched_batch_wakeup_granularity;
 extern unsigned int sysctl_sched_stat_granularity;

kernel/sched.c

@@ -4913,9 +4913,9 @@ static inline void sched_init_granularity(void)
 	unsigned int factor = 1 + ilog2(num_online_cpus());
 	const unsigned long limit = 100000000;
 
-	sysctl_sched_granularity *= factor;
-	if (sysctl_sched_granularity > limit)
-		sysctl_sched_granularity = limit;
+	sysctl_sched_min_granularity *= factor;
+	if (sysctl_sched_min_granularity > limit)
+		sysctl_sched_min_granularity = limit;
 
 	sysctl_sched_latency *= factor;
 	if (sysctl_sched_latency > limit)

kernel/sched_fair.c

@@ -40,7 +40,7 @@ unsigned int sysctl_sched_latency __read_mostly = 20000000ULL;
  * Minimal preemption granularity for CPU-bound tasks:
  * (default: 2 msec, units: nanoseconds)
  */
-unsigned int sysctl_sched_granularity __read_mostly = 2000000ULL;
+unsigned int sysctl_sched_min_granularity __read_mostly = 2000000ULL;
 
 /*
  * SCHED_BATCH wake-up granularity.
@@ -258,7 +258,7 @@ sched_granularity(struct cfs_rq *cfs_rq)
 
 	if (nr > 1) {
 		gran = gran/nr - gran/nr/nr;
-		gran = max(gran, sysctl_sched_granularity);
+		gran = max(gran, sysctl_sched_min_granularity);
 	}
 
 	return gran;

kernel/sysctl.c

@@ -222,8 +222,8 @@ static ctl_table kern_table[] = {
 #ifdef CONFIG_SCHED_DEBUG
 	{
 		.ctl_name	= CTL_UNNUMBERED,
-		.procname	= "sched_granularity_ns",
-		.data		= &sysctl_sched_granularity,
+		.procname	= "sched_min_granularity_ns",
+		.data		= &sysctl_sched_min_granularity,
 		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
 		.proc_handler	= &proc_dointvec_minmax,