Commit-ID: 9916e214998a4a363b152b637245e5c958067350
Gitweb: http://git.kernel.org/tip/9916e214998a4a363b152b637245e5c958067350
Author: Peter Zijlstra <[email protected]>
AuthorDate: Thu, 11 Jun 2015 14:46:43 +0200
Committer: Thomas Gleixner <[email protected]>
CommitDate: Fri, 19 Jun 2015 00:25:26 +0200
sched, dl: Convert switched_{from, to}_dl() / prio_changed_dl() to balance
callbacks
Remove the direct {push,pull} balancing operations from
switched_{from,to}_dl() / prio_changed_dl() and use the balance
callback queue.
Again, err on the side of too many reschedules; since too few is a
hard bug while too many is just annoying.
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
---
kernel/sched/deadline.c | 45 ++++++++++++++++++++++++---------------------
1 file changed, 24 insertions(+), 21 deletions(-)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 079c092..69d9f50 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -213,16 +213,23 @@ static inline bool need_pull_dl_task(struct rq *rq,
struct task_struct *prev)
return dl_task(prev);
}
-static DEFINE_PER_CPU(struct callback_head, dl_balance_head);
+static DEFINE_PER_CPU(struct callback_head, dl_push_head);
+static DEFINE_PER_CPU(struct callback_head, dl_pull_head);
static void push_dl_tasks(struct rq *);
+static void pull_dl_task(struct rq *);
static inline void queue_push_tasks(struct rq *rq)
{
if (!has_pushable_dl_tasks(rq))
return;
- queue_balance_callback(rq, &per_cpu(dl_balance_head, rq->cpu),
push_dl_tasks);
+ queue_balance_callback(rq, &per_cpu(dl_push_head, rq->cpu),
push_dl_tasks);
+}
+
+static inline void queue_pull_task(struct rq *rq)
+{
+ queue_balance_callback(rq, &per_cpu(dl_pull_head, rq->cpu),
pull_dl_task);
}
static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq);
@@ -305,6 +312,10 @@ static inline void pull_dl_task(struct rq *rq)
static inline void queue_push_tasks(struct rq *rq)
{
}
+
+static inline void queue_pull_task(struct rq *rq)
+{
+}
#endif /* CONFIG_SMP */
static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags);
@@ -1040,8 +1051,6 @@ static void check_preempt_equal_dl(struct rq *rq, struct
task_struct *p)
resched_curr(rq);
}
-static void pull_dl_task(struct rq *this_rq);
-
#endif /* CONFIG_SMP */
/*
@@ -1705,7 +1714,7 @@ static void switched_from_dl(struct rq *rq, struct
task_struct *p)
if (!task_on_rq_queued(p) || rq->dl.dl_nr_running)
return;
- pull_dl_task(rq);
+ queue_pull_task(rq);
}
/*
@@ -1714,21 +1723,16 @@ static void switched_from_dl(struct rq *rq, struct
task_struct *p)
*/
static void switched_to_dl(struct rq *rq, struct task_struct *p)
{
- int check_resched = 1;
-
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
- if (p->nr_cpus_allowed > 1 && rq->dl.overloaded &&
- push_dl_task(rq) && rq != task_rq(p))
- /* Only reschedule if pushing failed */
- check_resched = 0;
-#endif /* CONFIG_SMP */
- if (check_resched) {
- if (dl_task(rq->curr))
- check_preempt_curr_dl(rq, p, 0);
- else
- resched_curr(rq);
- }
+ if (p->nr_cpus_allowed > 1 && rq->dl.overloaded)
+ queue_push_tasks(rq);
+#else
+ if (dl_task(rq->curr))
+ check_preempt_curr_dl(rq, p, 0);
+ else
+ resched_curr(rq);
+#endif
}
}
@@ -1748,15 +1752,14 @@ static void prio_changed_dl(struct rq *rq, struct
task_struct *p,
* or lowering its prio, so...
*/
if (!rq->dl.overloaded)
- pull_dl_task(rq);
+ queue_pull_task(rq);
/*
* If we now have a earlier deadline task than p,
* then reschedule, provided p is still on this
* runqueue.
*/
- if (dl_time_before(rq->dl.earliest_dl.curr, p->dl.deadline) &&
- rq->curr == p)
+ if (dl_time_before(rq->dl.earliest_dl.curr, p->dl.deadline))
resched_curr(rq);
#else
/*
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
