[PATCH v2 5/7] sched/core: Reset RQCF_ACT_SKIP before unpinning rq->lock

[Matt Fleming]

rq_clock() is called from sched_info_{depart,arrive}() after resetting
RQCF_ACT_SKIP but prior to a call to update_rq_clock().

In preparation for pending patches that check whether the rq clock has
been updated inside of a pin context before rq_clock() is called, move
the reset of rq->clock_skip_update immediately before unpinning the rq
lock.

This will avoid the new warnings which check if update_rq_clock() is
being actively skipped.

Cc: Peter Zijlstra 
Cc: Ingo Molnar 
Cc: Mike Galbraith 
Cc: Mel Gorman 
Signed-off-by: Matt Fleming 
---
 kernel/sched/core.c | 5 -
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 7950c372fca0..1254629c9f2f 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2871,6 +2871,9 @@ context_switch(struct rq *rq, struct task_struct *prev,
prev->active_mm = NULL;
rq->prev_mm = oldmm;
}
+
+   rq->clock_skip_update = 0;
+
/*
 * Since the runqueue lock will be released by the next
 * task (which is an invalid locking op but in the case
@@ -3387,7 +3390,6 @@ static void __sched notrace __schedule(bool preempt)
next = pick_next_task(rq, prev, );
clear_tsk_need_resched(prev);
clear_preempt_need_resched();
-   rq->clock_skip_update = 0;
 
if (likely(prev != next)) {
rq->nr_switches++;
@@ -3397,6 +3399,7 @@ static void __sched notrace __schedule(bool preempt)
trace_sched_switch(preempt, prev, next);
rq = context_switch(rq, prev, next, ); /* unlocks the rq */
} else {
+   rq->clock_skip_update = 0;
rq_unpin_lock(rq, );
raw_spin_unlock_irq(>lock);
}
-- 
2.9.3

[PATCH v2 5/7] sched/core: Reset RQCF_ACT_SKIP before unpinning rq->lock

[Matt Fleming]

rq_clock() is called from sched_info_{depart,arrive}() after resetting
RQCF_ACT_SKIP but prior to a call to update_rq_clock().

In preparation for pending patches that check whether the rq clock has
been updated inside of a pin context before rq_clock() is called, move
the reset of rq->clock_skip_update immediately before unpinning the rq
lock.

This will avoid the new warnings which check if update_rq_clock() is
being actively skipped.

Cc: Peter Zijlstra 
Cc: Ingo Molnar 
Cc: Mike Galbraith 
Cc: Mel Gorman 
Signed-off-by: Matt Fleming 
---
 kernel/sched/core.c | 5 -
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 7950c372fca0..1254629c9f2f 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2871,6 +2871,9 @@ context_switch(struct rq *rq, struct task_struct *prev,
prev->active_mm = NULL;
rq->prev_mm = oldmm;
}
+
+   rq->clock_skip_update = 0;
+
/*
 * Since the runqueue lock will be released by the next
 * task (which is an invalid locking op but in the case
@@ -3387,7 +3390,6 @@ static void __sched notrace __schedule(bool preempt)
next = pick_next_task(rq, prev, );
clear_tsk_need_resched(prev);
clear_preempt_need_resched();
-   rq->clock_skip_update = 0;
 
if (likely(prev != next)) {
rq->nr_switches++;
@@ -3397,6 +3399,7 @@ static void __sched notrace __schedule(bool preempt)
trace_sched_switch(preempt, prev, next);
rq = context_switch(rq, prev, next, ); /* unlocks the rq */
} else {
+   rq->clock_skip_update = 0;
rq_unpin_lock(rq, );
raw_spin_unlock_irq(>lock);
}
-- 
2.9.3