From: Hiroshi Shimamoto <[email protected]>
Current the initial SCHED_RR timeslice of init_task is HZ, which means
1s, and is not same as the default SCHED_RR timeslice DEF_TIMESLICE.
Change the initial timeslice to the RR_TIMESLICE, which is renamed from
DEF_TIMESLICE to clarify it's for SCHED_RR.
Signed-off-by: Hiroshi Shimamoto <[email protected]>
CC: Peter Zijlstra <[email protected]>
---
include/linux/init_task.h | 2 +-
include/linux/sched.h | 6 ++++++
kernel/sched/rt.c | 4 ++--
kernel/sched/sched.h | 4 ----
4 files changed, 9 insertions(+), 7 deletions(-)
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 9c66b1a..f994d51 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -149,7 +149,7 @@ extern struct cred init_cred;
}, \
.rt = { \
.run_list = LIST_HEAD_INIT(tsk.rt.run_list), \
- .time_slice = HZ, \
+ .time_slice = RR_TIMESLICE, \
.nr_cpus_allowed = NR_CPUS, \
}, \
.tasks = LIST_HEAD_INIT(tsk.tasks), \
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 2df7646..ee882cb 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1234,6 +1234,12 @@ struct sched_rt_entity {
#endif
};
+/*
+ * default timeslice is 100 msecs (used only for SCHED_RR tasks).
+ * Timeslices get refilled after they expire.
+ */
+#define RR_TIMESLICE (100 * HZ / 1000)
+
struct rcu_node;
enum perf_event_task_context {
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index f42ae7f..f70206c 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1972,7 +1972,7 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
if (--p->rt.time_slice)
return;
- p->rt.time_slice = DEF_TIMESLICE;
+ p->rt.time_slice = RR_TIMESLICE;
/*
* Requeue to the end of queue if we are not the only element
@@ -2000,7 +2000,7 @@ static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)
* Time slice is 0 for SCHED_FIFO tasks
*/
if (task->policy == SCHED_RR)
- return DEF_TIMESLICE;
+ return RR_TIMESLICE;
else
return 0;
}
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 8a2c768..c0660a1 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -36,11 +36,7 @@ extern __read_mostly int scheduler_running;
/*
* These are the 'tuning knobs' of the scheduler:
- *
- * default timeslice is 100 msecs (used only for SCHED_RR tasks).
- * Timeslices get refilled after they expire.
*/
-#define DEF_TIMESLICE (100 * HZ / 1000)
/*
* single value that denotes runtime == period, ie unlimited time.
--
1.7.7.6