sched: use constants if !CONFIG_SCHED_DEBUG
use constants if !CONFIG_SCHED_DEBUG.
this speeds up the code and reduces code-size:
text data bss dec hex filename
27464 3014 16 30494 771e sched.o.before
26929 3010 20 29959 7507 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 5c15d8a..2e84aaf 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -21,6 +21,15 @@
*/
/*
+ * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
+ */
+#ifdef CONFIG_SCHED_DEBUG
+# define const_debug __read_mostly
+#else
+# define const_debug static const
+#endif
+
+/*
* Targeted preemption latency for CPU-bound tasks:
* (default: 20ms, units: nanoseconds)
*
@@ -34,7 +43,13 @@
* systems, 4x on 8-way systems, 5x on 16-way systems, etc.)
* Targeted preemption latency for CPU-bound tasks:
*/
-unsigned int sysctl_sched_latency __read_mostly = 20000000ULL;
+const_debug unsigned int sysctl_sched_latency = 20000000ULL;
+
+/*
+ * After fork, child runs first. (default) If set to 0 then
+ * parent will (try to) run first.
+ */
+const_debug unsigned int sysctl_sched_child_runs_first = 1;
/*
* Minimal preemption granularity for CPU-bound tasks:
@@ -58,7 +73,7 @@
* and reduces their over-scheduling. Synchronous workloads will still
* have immediate wakeup/sleep latencies.
*/
-unsigned int sysctl_sched_batch_wakeup_granularity __read_mostly = 25000000UL;
+const_debug unsigned int sysctl_sched_batch_wakeup_granularity = 25000000UL;
/*
* SCHED_OTHER wake-up granularity.
@@ -68,13 +83,10 @@
* and reduces their over-scheduling. Synchronous workloads will still
* have immediate wakeup/sleep latencies.
*/
-unsigned int sysctl_sched_wakeup_granularity __read_mostly = 1000000UL;
+const_debug unsigned int sysctl_sched_wakeup_granularity = 1000000UL;
-unsigned int sysctl_sched_stat_granularity __read_mostly;
+const_debug unsigned int sysctl_sched_stat_granularity;
-/*
- * Initialized in sched_init_granularity() [to 5 times the base granularity]:
- */
unsigned int sysctl_sched_runtime_limit __read_mostly;
/*
@@ -89,7 +101,7 @@
SCHED_FEAT_SKIP_INITIAL = 32,
};
-unsigned int sysctl_sched_features __read_mostly =
+const_debug unsigned int sysctl_sched_features =
SCHED_FEAT_FAIR_SLEEPERS *1 |
SCHED_FEAT_SLEEPER_AVG *0 |
SCHED_FEAT_SLEEPER_LOAD_AVG *1 |