[RFCv5 PATCH 27/46] sched, cpuidle: Track cpuidle state index in the scheduler

Morten Rasmussen
2015-07-07T18:25:17Z

The idle-state of each cpu is currently pointed to by rq->idle_state but
there isn't any information in the struct cpuidle_state that can used to
look up the idle-state energy model data stored in struct
sched_group_energy. For this purpose is necessary to store the idle
state index as well. Ideally, the idle-state data should be unified.

cc: Ingo Molnar <mingo@redhat.com>
cc: Peter Zijlstra <peterz@infradead.org>

Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
---
kernel/sched/idle.c | 2 ++
kernel/sched/sched.h | 21 +++++++++++++++++++++
2 files changed, 23 insertions(+)

diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index fefcb1f..6832fa1 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -151,6 +151,7 @@ static void cpuidle_idle_call(void)

/* Take note of the planned idle state. */
idle_set_state(this_rq(), &drv->states[next_state]);
+ idle_set_state_idx(this_rq(), next_state);

/*
* Enter the idle state previously returned by the governor decision.
@@ -161,6 +162,7 @@ static void cpuidle_idle_call(void)

/* The cpu is no longer idle or about to enter idle. */
idle_set_state(this_rq(), NULL);
+ idle_set_state_idx(this_rq(), -1);

if (entered_state == -EBUSY)
goto use_default;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 9589d9e..c395559 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -701,6 +701,7 @@ struct rq {
#ifdef CONFIG_CPU_IDLE
/* Must be inspected within a rcu lock section */
struct cpuidle_state *idle_state;
+ int idle_state_idx;
#endif
};

@@ -1316,6 +1317,17 @@ static inline struct cpuidle_state *idle_get_state(struct rq *rq)
WARN_ON(!rcu_read_lock_held());
return rq->idle_state;
}
+
+static inline void idle_set_state_idx(struct rq *rq, int idle_state_idx)
+{
+ rq->idle_state_idx = idle_state_idx;
+}
+
+static inline int idle_get_state_idx(struct rq *rq)
+{
+ WARN_ON(!rcu_read_lock_held());
+ return rq->idle_state_idx;
+}
#else
static inline void idle_set_state(struct rq *rq,
struct cpuidle_state *idle_state)
@@ -1326,6 +1338,15 @@ static inline struct cpuidle_state *idle_get_state(struct rq *rq)
{
return NULL;
}
+
+static inline void idle_set_state_idx(struct rq *rq, int idle_state_idx)
+{
+}
+
+static inline int idle_get_state_idx(struct rq *rq)
+{
+ return -1;
+}
#endif

extern void sysrq_sched_debug_show(void);
--
1.9.1