Wrap repeated code in helper function dl_task_is_earliest_deadline, which
return true if there is no deadline task on the rq at all, or task's
deadline earlier than the whole rq.
Signed-off-by: Shang XiaoJing <[email protected]>
---
changes in v2:
- pick a more descriptive function name rather than compare_task_rq.
---
kernel/sched/deadline.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index d116d2b9d2f9..34271aff4712 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1810,6 +1810,14 @@ static void yield_task_dl(struct rq *rq)
#ifdef CONFIG_SMP
+static inline bool dl_task_is_earliest_deadline(struct task_struct *p,
+ struct rq *rq)
+{
+ return (!rq->dl.dl_nr_running ||
+ dl_time_before(p->dl.deadline,
+ rq->dl.earliest_dl.curr));
+}
+
static int find_later_rq(struct task_struct *task);
static int
@@ -1852,9 +1860,7 @@ select_task_rq_dl(struct task_struct *p, int cpu, int flags)
int target = find_later_rq(p);
if (target != -1 &&
- (dl_time_before(p->dl.deadline,
- cpu_rq(target)->dl.earliest_dl.curr) ||
- (cpu_rq(target)->dl.dl_nr_running == 0)))
+ dl_task_is_earliest_deadline(p, cpu_rq(target)))
cpu = target;
}
rcu_read_unlock();
@@ -2221,9 +2227,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
later_rq = cpu_rq(cpu);
- if (later_rq->dl.dl_nr_running &&
- !dl_time_before(task->dl.deadline,
- later_rq->dl.earliest_dl.curr)) {
+ if (!dl_task_is_earliest_deadline(task, later_rq)) {
/*
* Target rq has tasks of equal or earlier deadline,
* retrying does not release any lock and is unlikely
@@ -2251,9 +2255,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
* its earliest one has a later deadline than our
* task, the rq is a good one.
*/
- if (!later_rq->dl.dl_nr_running ||
- dl_time_before(task->dl.deadline,
- later_rq->dl.earliest_dl.curr))
+ if (dl_task_is_earliest_deadline(task, later_rq))
break;
/* Otherwise we try again. */
@@ -2424,9 +2426,7 @@ static void pull_dl_task(struct rq *this_rq)
* - it will preempt the last one we pulled (if any).
*/
if (p && dl_time_before(p->dl.deadline, dmin) &&
- (!this_rq->dl.dl_nr_running ||
- dl_time_before(p->dl.deadline,
- this_rq->dl.earliest_dl.curr))) {
+ dl_task_is_earliest_deadline(p, this_rq)) {
WARN_ON(p == src_rq->curr);
WARN_ON(!task_on_rq_queued(p));
--
2.17.1
On 8/26/22 10:34, Shang XiaoJing wrote:
> Wrap repeated code in helper function dl_task_is_earliest_deadline, which
> return true if there is no deadline task on the rq at all, or task's
> deadline earlier than the whole rq.
>
> Signed-off-by: Shang XiaoJing <[email protected]>
Reviewed-by: Daniel Bristot de Oliveira <[email protected]>
-- Daniel
The following commit has been merged into the sched/core branch of tip:
Commit-ID: 973bee493a1f75c6c0752a74fb9396cbc34f026e
Gitweb: https://git.kernel.org/tip/973bee493a1f75c6c0752a74fb9396cbc34f026e
Author: Shang XiaoJing <[email protected]>
AuthorDate: Fri, 26 Aug 2022 16:34:53 +08:00
Committer: Peter Zijlstra <[email protected]>
CommitterDate: Thu, 01 Sep 2022 11:19:54 +02:00
sched/deadline: Add dl_task_is_earliest_deadline helper
Wrap repeated code in helper function dl_task_is_earliest_deadline, which
return true if there is no deadline task on the rq at all, or task's
deadline earlier than the whole rq.
Signed-off-by: Shang XiaoJing <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Daniel Bristot de Oliveira <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
kernel/sched/deadline.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index d116d2b..34271af 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1810,6 +1810,14 @@ static void yield_task_dl(struct rq *rq)
#ifdef CONFIG_SMP
+static inline bool dl_task_is_earliest_deadline(struct task_struct *p,
+ struct rq *rq)
+{
+ return (!rq->dl.dl_nr_running ||
+ dl_time_before(p->dl.deadline,
+ rq->dl.earliest_dl.curr));
+}
+
static int find_later_rq(struct task_struct *task);
static int
@@ -1852,9 +1860,7 @@ select_task_rq_dl(struct task_struct *p, int cpu, int flags)
int target = find_later_rq(p);
if (target != -1 &&
- (dl_time_before(p->dl.deadline,
- cpu_rq(target)->dl.earliest_dl.curr) ||
- (cpu_rq(target)->dl.dl_nr_running == 0)))
+ dl_task_is_earliest_deadline(p, cpu_rq(target)))
cpu = target;
}
rcu_read_unlock();
@@ -2221,9 +2227,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
later_rq = cpu_rq(cpu);
- if (later_rq->dl.dl_nr_running &&
- !dl_time_before(task->dl.deadline,
- later_rq->dl.earliest_dl.curr)) {
+ if (!dl_task_is_earliest_deadline(task, later_rq)) {
/*
* Target rq has tasks of equal or earlier deadline,
* retrying does not release any lock and is unlikely
@@ -2251,9 +2255,7 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
* its earliest one has a later deadline than our
* task, the rq is a good one.
*/
- if (!later_rq->dl.dl_nr_running ||
- dl_time_before(task->dl.deadline,
- later_rq->dl.earliest_dl.curr))
+ if (dl_task_is_earliest_deadline(task, later_rq))
break;
/* Otherwise we try again. */
@@ -2424,9 +2426,7 @@ static void pull_dl_task(struct rq *this_rq)
* - it will preempt the last one we pulled (if any).
*/
if (p && dl_time_before(p->dl.deadline, dmin) &&
- (!this_rq->dl.dl_nr_running ||
- dl_time_before(p->dl.deadline,
- this_rq->dl.earliest_dl.curr))) {
+ dl_task_is_earliest_deadline(p, this_rq)) {
WARN_ON(p == src_rq->curr);
WARN_ON(!task_on_rq_queued(p));