sched: remove sysctl_sched_batch_wakeup_granularity

it's unused.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/linux/sched.h

@@ -1551,7 +1551,6 @@ static inline void wake_up_idle_cpu(int cpu) { }
 extern unsigned int sysctl_sched_latency;
 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_child_runs_first;
 extern unsigned int sysctl_sched_features;
 extern unsigned int sysctl_sched_migration_cost;

kernel/sched.c

@@ -5396,7 +5396,6 @@ static inline void sched_init_granularity(void)
 		sysctl_sched_latency = limit;
 
 	sysctl_sched_wakeup_granularity *= factor;
-	sysctl_sched_batch_wakeup_granularity *= factor;
 }
 
 #ifdef CONFIG_SMP

kernel/sched_debug.c

@@ -214,7 +214,6 @@ static int sched_debug_show(struct seq_file *m, void *v)
 	PN(sysctl_sched_latency);
 	PN(sysctl_sched_min_granularity);
 	PN(sysctl_sched_wakeup_granularity);
-	PN(sysctl_sched_batch_wakeup_granularity);
 	PN(sysctl_sched_child_runs_first);
 	P(sysctl_sched_features);
 #undef PN

kernel/sched_fair.c

@@ -61,16 +61,6 @@ const_debug unsigned int sysctl_sched_child_runs_first = 1;
  */
 unsigned int __read_mostly sysctl_sched_compat_yield;
 
-/*
- * SCHED_BATCH wake-up granularity.
- * (default: 10 msec * (1 + ilog(ncpus)), units: nanoseconds)
- *
- * This option delays the preemption effects of decoupled workloads
- * and reduces their over-scheduling. Synchronous workloads will still
- * have immediate wakeup/sleep latencies.
- */
-unsigned int sysctl_sched_batch_wakeup_granularity = 10000000UL;
-
 /*
  * SCHED_OTHER wake-up granularity.
  * (default: 10 msec * (1 + ilog(ncpus)), units: nanoseconds)

kernel/sysctl.c

@@ -268,17 +268,6 @@ static struct ctl_table kern_table[] = {
 		.extra1		= &min_wakeup_granularity_ns,
 		.extra2		= &max_wakeup_granularity_ns,
 	},
-	{
-		.ctl_name	= CTL_UNNUMBERED,
-		.procname	= "sched_batch_wakeup_granularity_ns",
-		.data		= &sysctl_sched_batch_wakeup_granularity,
-		.maxlen		= sizeof(unsigned int),
-		.mode		= 0644,
-		.proc_handler	= &proc_dointvec_minmax,
-		.strategy	= &sysctl_intvec,
-		.extra1		= &min_wakeup_granularity_ns,
-		.extra2		= &max_wakeup_granularity_ns,
-	},
 	{
 		.ctl_name	= CTL_UNNUMBERED,
 		.procname	= "sched_child_runs_first",