With this patch it is possible to differentiate the idle tick stop from
the SCHED_FIFO tick stop.
Signed-off-by: Jan Blunck <jblunck@xxxxxxx>
---
include/linux/tick.h | 14 ++++++++++++--
include/trace/events/sched.h | 22 ++++++++++++++--------
kernel/sched_rt.c | 4 ++--
kernel/softirq.c | 2 +-
kernel/time/tick-sched.c | 20 +++++++++++---------
5 files changed, 40 insertions(+), 22 deletions(-)
diff --git a/include/linux/tick.h b/include/linux/tick.h
index b232ccc..37b3d78 100644
--- a/include/linux/tick.h
+++ b/include/linux/tick.h
@@ -121,13 +121,23 @@ static inline int tick_oneshot_mode_active(void) { return 0; }
#endif /* !CONFIG_GENERIC_CLOCKEVENTS */
# ifdef CONFIG_NO_HZ
-extern void tick_nohz_stop_sched_tick(int inidle);
-extern void tick_nohz_restart_sched_tick(void);
+extern void __tick_nohz_stop_sched_tick(int inidle, int insched);
+static inline void tick_nohz_stop_sched_tick(int inidle)
+{
+ __tick_nohz_stop_sched_tick(inidle, 0);
+}
+extern void __tick_nohz_restart_sched_tick(int insched);
+static inline void tick_nohz_restart_sched_tick(void)
+{
+ __tick_nohz_restart_sched_tick(0);
+}
extern ktime_t tick_nohz_get_sleep_length(void);
extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
# else
+static inline void __tick_nohz_stop_sched_tick(int inidle, int insched) { }
static inline void tick_nohz_stop_sched_tick(int inidle) { }
+static inline void __tick_nohz_restart_sched_tick(int insched) { }
static inline void tick_nohz_restart_sched_tick(void) { }
static inline ktime_t tick_nohz_get_sleep_length(void)
{
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index 36385b6..fd4307e 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -382,41 +382,47 @@ TRACE_EVENT(sched_stat_runtime,
TRACE_EVENT(sched_tick_start,
- TP_PROTO(ktime_t *now),
+ TP_PROTO(ktime_t *now, int sched_rt),
- TP_ARGS(now),
+ TP_ARGS(now, sched_rt),
TP_STRUCT__entry(
__field(s64, tv64)
+ __field(int, sched_rt)
),
TP_fast_assign(
__entry->tv64 = now->tv64;
+ __entry->sched_rt = sched_rt;
),
- TP_printk("now=%ld",
- (long)__entry->tv64)
+ TP_printk("now=%ld%s",
+ (long)__entry->tv64,
+ __entry->sched_rt ? ", SCHED_FIFO" : "")
);
TRACE_EVENT(sched_tick_stop,
- TP_PROTO(ktime_t *expires, int idle),
+ TP_PROTO(ktime_t *expires, int idle, int sched_rt),
- TP_ARGS(expires, idle),
+ TP_ARGS(expires, idle, sched_rt),
TP_STRUCT__entry(
__field(s64, tv64)
__field(int, idle)
+ __field(int, sched_rt)
),
TP_fast_assign(
__entry->tv64 = expires->tv64;
__entry->idle = idle;
+ __entry->sched_rt = sched_rt;
),
- TP_printk("idle=%d, expires=%ld%s",
+ TP_printk("idle=%d, expires=%ld%s%s",
__entry->idle,
(long)__entry->tv64,
- (__entry->tv64 == KTIME_MAX) ? " (KTIME_MAX)" : "" )
+ (__entry->tv64 == KTIME_MAX) ? " (KTIME_MAX)" : "",
+ __entry->sched_rt ? ", SCHED_FIFO" : "" )
);
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 3879ca1..c9386da 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1486,7 +1486,7 @@ static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
/* Enable sched_tick again before we schedule */
if (unlikely(rt_task(prev)) && !(prev->flags & PF_KTHREAD) &&
(prev->policy == SCHED_FIFO)) {
- tick_nohz_restart_sched_tick();
+ __tick_nohz_restart_sched_tick(1);
/* Disable tick in post_schedule if we don't switch */
rq->post_schedule = 1;
@@ -1502,7 +1502,7 @@ static void post_schedule_rt(struct rq *rq)
unlikely(!local_softirq_pending()) &&
!(rq->curr->flags & PF_KTHREAD) &&
(rq->curr->policy == SCHED_FIFO))
- tick_nohz_stop_sched_tick(1);
+ __tick_nohz_stop_sched_tick(1, 1);
}
/*
diff --git a/kernel/softirq.c b/kernel/softirq.c
index ff05f6a..f0973be 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -311,7 +311,7 @@ void irq_exit(void)
/* Disable tick if the current task is FIFO */
if (unlikely(rt_task(current) && !(current->flags & PF_KTHREAD) &&
current->policy == SCHED_FIFO))
- tick_nohz_stop_sched_tick(1);
+ __tick_nohz_stop_sched_tick(1, 1);
#endif
preempt_enable_no_resched();
}
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 567110d..2a3bd0a 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -257,7 +257,7 @@ EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us);
* Called either from the idle loop or from irq_exit() when an idle period was
* just interrupted by an interrupt which did not cause a reschedule.
*/
-void tick_nohz_stop_sched_tick(int inidle)
+void __tick_nohz_stop_sched_tick(int inidle, int insched)
{
unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags;
struct tick_sched *ts;
@@ -432,7 +432,8 @@ void tick_nohz_stop_sched_tick(int inidle)
*/
if (unlikely(expires.tv64 == KTIME_MAX)) {
if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
- trace_sched_tick_stop(&expires, inidle);
+ trace_sched_tick_stop(&expires, inidle,
+ insched);
hrtimer_cancel(&ts->sched_timer);
}
goto out;
@@ -443,11 +444,12 @@ void tick_nohz_stop_sched_tick(int inidle)
HRTIMER_MODE_ABS_PINNED);
/* Check, if the timer was already in the past */
if (hrtimer_active(&ts->sched_timer)) {
- trace_sched_tick_stop(&expires, inidle);
+ trace_sched_tick_stop(&expires, inidle,
+ insched);
goto out;
}
} else if (!tick_program_event(expires, 0)) {
- trace_sched_tick_stop(&expires, inidle);
+ trace_sched_tick_stop(&expires, inidle, insched);
goto out;
}
@@ -480,7 +482,7 @@ ktime_t tick_nohz_get_sleep_length(void)
return ts->sleep_length;
}
-static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
+static void tick_nohz_restart(struct tick_sched *ts, ktime_t now, int insched)
{
hrtimer_cancel(&ts->sched_timer);
hrtimer_set_expires(&ts->sched_timer, ts->idle_tick);
@@ -505,7 +507,7 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
now = ktime_get();
}
- trace_sched_tick_start(&now);
+ trace_sched_tick_start(&now, insched);
}
/**
@@ -513,7 +515,7 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
*
* Restart the idle tick when the CPU is woken up from idle
*/
-void tick_nohz_restart_sched_tick(void)
+void __tick_nohz_restart_sched_tick(int insched)
{
int cpu = smp_processor_id();
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
@@ -566,7 +568,7 @@ void tick_nohz_restart_sched_tick(void)
ts->tick_stopped = 0;
ts->idle_exittime = now;
- tick_nohz_restart(ts, now);
+ tick_nohz_restart(ts, now, insched);
local_irq_restore(flags);
}
@@ -691,7 +693,7 @@ static void tick_nohz_kick_tick(int cpu, ktime_t now)
if (delta.tv64 <= tick_period.tv64)
return;
- tick_nohz_restart(ts, now);
+ tick_nohz_restart(ts, now, 0);
#endif
}
--
1.6.4.2
--
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