[PATCH 06/10] sched/core: Remove the tsk_nr_cpus_allowed() wrapper

From: Ingo Molnar
Date: Wed Feb 08 2017 - 13:37:41 EST


tsk_nr_cpus_allowed() too is a pretty pointless wrapper that
is not used consistently and which makes the code both harder
to read and longer as well.

So remove it - this also shrinks <linux/sched.h> a bit.

Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
include/linux/sched.h | 5 -----
kernel/sched/core.c | 2 +-
kernel/sched/deadline.c | 28 ++++++++++++++--------------
kernel/sched/rt.c | 24 ++++++++++++------------
4 files changed, 27 insertions(+), 32 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 38af022b351d..4e2e738e2c61 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1999,11 +1999,6 @@ static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t)
}
#endif

-static inline int tsk_nr_cpus_allowed(struct task_struct *p)
-{
- return p->nr_cpus_allowed;
-}
-
#define TNF_MIGRATED 0x01
#define TNF_NO_GROUP 0x02
#define TNF_SHARED 0x04
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0706863f83b5..258af6d00682 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1545,7 +1545,7 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
{
lockdep_assert_held(&p->pi_lock);

- if (tsk_nr_cpus_allowed(p) > 1)
+ if (p->nr_cpus_allowed > 1)
cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
else
cpu = cpumask_any(&p->cpus_allowed);
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 8e4d6e4e3ccc..99b2c33a9fbc 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -134,7 +134,7 @@ static void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
struct task_struct *p = dl_task_of(dl_se);

- if (tsk_nr_cpus_allowed(p) > 1)
+ if (p->nr_cpus_allowed > 1)
dl_rq->dl_nr_migratory++;

update_dl_migration(dl_rq);
@@ -144,7 +144,7 @@ static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
struct task_struct *p = dl_task_of(dl_se);

- if (tsk_nr_cpus_allowed(p) > 1)
+ if (p->nr_cpus_allowed > 1)
dl_rq->dl_nr_migratory--;

update_dl_migration(dl_rq);
@@ -958,7 +958,7 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)

enqueue_dl_entity(&p->dl, pi_se, flags);

- if (!task_current(rq, p) && tsk_nr_cpus_allowed(p) > 1)
+ if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
enqueue_pushable_dl_task(rq, p);
}

@@ -1032,9 +1032,9 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags)
* try to make it stay here, it might be important.
*/
if (unlikely(dl_task(curr)) &&
- (tsk_nr_cpus_allowed(curr) < 2 ||
+ (curr->nr_cpus_allowed < 2 ||
!dl_entity_preempt(&p->dl, &curr->dl)) &&
- (tsk_nr_cpus_allowed(p) > 1)) {
+ (p->nr_cpus_allowed > 1)) {
int target = find_later_rq(p);

if (target != -1 &&
@@ -1055,7 +1055,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p)
* Current can't be migrated, useless to reschedule,
* let's hope p can move out.
*/
- if (tsk_nr_cpus_allowed(rq->curr) == 1 ||
+ if (rq->curr->nr_cpus_allowed == 1 ||
cpudl_find(&rq->rd->cpudl, rq->curr, NULL) == -1)
return;

@@ -1063,7 +1063,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p)
* p is migratable, so let's not schedule it and
* see if it is pushed or pulled somewhere else.
*/
- if (tsk_nr_cpus_allowed(p) != 1 &&
+ if (p->nr_cpus_allowed != 1 &&
cpudl_find(&rq->rd->cpudl, p, NULL) != -1)
return;

@@ -1178,7 +1178,7 @@ static void put_prev_task_dl(struct rq *rq, struct task_struct *p)
{
update_curr_dl(rq);

- if (on_dl_rq(&p->dl) && tsk_nr_cpus_allowed(p) > 1)
+ if (on_dl_rq(&p->dl) && p->nr_cpus_allowed > 1)
enqueue_pushable_dl_task(rq, p);
}

@@ -1279,7 +1279,7 @@ static int find_later_rq(struct task_struct *task)
if (unlikely(!later_mask))
return -1;

- if (tsk_nr_cpus_allowed(task) == 1)
+ if (task->nr_cpus_allowed == 1)
return -1;

/*
@@ -1424,7 +1424,7 @@ static struct task_struct *pick_next_pushable_dl_task(struct rq *rq)

BUG_ON(rq->cpu != task_cpu(p));
BUG_ON(task_current(rq, p));
- BUG_ON(tsk_nr_cpus_allowed(p) <= 1);
+ BUG_ON(p->nr_cpus_allowed <= 1);

BUG_ON(!task_on_rq_queued(p));
BUG_ON(!dl_task(p));
@@ -1463,7 +1463,7 @@ static int push_dl_task(struct rq *rq)
*/
if (dl_task(rq->curr) &&
dl_time_before(next_task->dl.deadline, rq->curr->dl.deadline) &&
- tsk_nr_cpus_allowed(rq->curr) > 1) {
+ rq->curr->nr_cpus_allowed > 1) {
resched_curr(rq);
return 0;
}
@@ -1610,9 +1610,9 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p)
{
if (!task_running(rq, p) &&
!test_tsk_need_resched(rq->curr) &&
- tsk_nr_cpus_allowed(p) > 1 &&
+ p->nr_cpus_allowed > 1 &&
dl_task(rq->curr) &&
- (tsk_nr_cpus_allowed(rq->curr) < 2 ||
+ (rq->curr->nr_cpus_allowed < 2 ||
!dl_entity_preempt(&p->dl, &rq->curr->dl))) {
push_dl_tasks(rq);
}
@@ -1726,7 +1726,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)

if (rq->curr != p) {
#ifdef CONFIG_SMP
- if (tsk_nr_cpus_allowed(p) > 1 && rq->dl.overloaded)
+ if (p->nr_cpus_allowed > 1 && rq->dl.overloaded)
queue_push_tasks(rq);
#endif
if (dl_task(rq->curr))
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index cbd356f63883..9f3e40226dec 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -335,7 +335,7 @@ static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
rt_rq = &rq_of_rt_rq(rt_rq)->rt;

rt_rq->rt_nr_total++;
- if (tsk_nr_cpus_allowed(p) > 1)
+ if (p->nr_cpus_allowed > 1)
rt_rq->rt_nr_migratory++;

update_rt_migration(rt_rq);
@@ -352,7 +352,7 @@ static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
rt_rq = &rq_of_rt_rq(rt_rq)->rt;

rt_rq->rt_nr_total--;
- if (tsk_nr_cpus_allowed(p) > 1)
+ if (p->nr_cpus_allowed > 1)
rt_rq->rt_nr_migratory--;

update_rt_migration(rt_rq);
@@ -1324,7 +1324,7 @@ enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)

enqueue_rt_entity(rt_se, flags);

- if (!task_current(rq, p) && tsk_nr_cpus_allowed(p) > 1)
+ if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
}

@@ -1413,7 +1413,7 @@ select_task_rq_rt(struct task_struct *p, int cpu, int sd_flag, int flags)
* will have to sort it out.
*/
if (curr && unlikely(rt_task(curr)) &&
- (tsk_nr_cpus_allowed(curr) < 2 ||
+ (curr->nr_cpus_allowed < 2 ||
curr->prio <= p->prio)) {
int target = find_lowest_rq(p);

@@ -1437,7 +1437,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
* Current can't be migrated, useless to reschedule,
* let's hope p can move out.
*/
- if (tsk_nr_cpus_allowed(rq->curr) == 1 ||
+ if (rq->curr->nr_cpus_allowed == 1 ||
!cpupri_find(&rq->rd->cpupri, rq->curr, NULL))
return;

@@ -1445,7 +1445,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
* p is migratable, so let's not schedule it and
* see if it is pushed or pulled somewhere else.
*/
- if (tsk_nr_cpus_allowed(p) != 1
+ if (p->nr_cpus_allowed != 1
&& cpupri_find(&rq->rd->cpupri, p, NULL))
return;

@@ -1579,7 +1579,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
* The previous task needs to be made eligible for pushing
* if it is still active
*/
- if (on_rt_rq(&p->rt) && tsk_nr_cpus_allowed(p) > 1)
+ if (on_rt_rq(&p->rt) && p->nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
}

@@ -1629,7 +1629,7 @@ static int find_lowest_rq(struct task_struct *task)
if (unlikely(!lowest_mask))
return -1;

- if (tsk_nr_cpus_allowed(task) == 1)
+ if (task->nr_cpus_allowed == 1)
return -1; /* No other targets possible */

if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
@@ -1761,7 +1761,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq)

BUG_ON(rq->cpu != task_cpu(p));
BUG_ON(task_current(rq, p));
- BUG_ON(tsk_nr_cpus_allowed(p) <= 1);
+ BUG_ON(p->nr_cpus_allowed <= 1);

BUG_ON(!task_on_rq_queued(p));
BUG_ON(!rt_task(p));
@@ -2121,9 +2121,9 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p)
{
if (!task_running(rq, p) &&
!test_tsk_need_resched(rq->curr) &&
- tsk_nr_cpus_allowed(p) > 1 &&
+ p->nr_cpus_allowed > 1 &&
(dl_task(rq->curr) || rt_task(rq->curr)) &&
- (tsk_nr_cpus_allowed(rq->curr) < 2 ||
+ (rq->curr->nr_cpus_allowed < 2 ||
rq->curr->prio <= p->prio))
push_rt_tasks(rq);
}
@@ -2196,7 +2196,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
*/
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
- if (tsk_nr_cpus_allowed(p) > 1 && rq->rt.overloaded)
+ if (p->nr_cpus_allowed > 1 && rq->rt.overloaded)
queue_push_tasks(rq);
#endif /* CONFIG_SMP */
if (p->prio < rq->curr->prio)
--
2.7.4