sched: add CFS debug sysctls

add CFS debug sysctls: only tweakable if SCHED_DEBUG is enabled.
This allows for faster debugging of scheduler problems.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 80 insertions, 0 deletions

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 30ee462ee79f..51f5dac42a00 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -206,7 +206,87 @@ static ctl_table root_table[] = {
         { .ctl_name = 0 }
 };
 
+#ifdef CONFIG_SCHED_DEBUG
+static unsigned long min_sched_granularity_ns = 100000;         /* 100 usecs */
+static unsigned long max_sched_granularity_ns = 1000000000;     /* 1 second */
+static unsigned long min_wakeup_granularity_ns;                 /* 0 usecs */
+static unsigned long max_wakeup_granularity_ns = 1000000000;    /* 1 second */
+#endif
+
 static ctl_table kern_table[] = {
+#ifdef CONFIG_SCHED_DEBUG
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "sched_granularity_ns",
+                .data           = &sysctl_sched_granularity,
+                .maxlen         = sizeof(unsigned int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec_minmax,
+                .strategy       = &sysctl_intvec,
+                .extra1         = &min_sched_granularity_ns,
+                .extra2         = &max_sched_granularity_ns,
+        },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "sched_wakeup_granularity_ns",
+                .data           = &sysctl_sched_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_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_stat_granularity_ns",
+                .data           = &sysctl_sched_stat_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_runtime_limit_ns",
+                .data           = &sysctl_sched_runtime_limit,
+                .maxlen         = sizeof(unsigned int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec_minmax,
+                .strategy       = &sysctl_intvec,
+                .extra1         = &min_sched_granularity_ns,
+                .extra2         = &max_sched_granularity_ns,
+        },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "sched_child_runs_first",
+                .data           = &sysctl_sched_child_runs_first,
+                .maxlen         = sizeof(unsigned int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec,
+        },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "sched_features",
+                .data           = &sysctl_sched_features,
+                .maxlen         = sizeof(unsigned int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec,
+        },
+#endif
         {
                 .ctl_name       = KERN_PANIC,
                 .procname       = "panic",