sched_ext: Replace consume_local_task() with move_local_task_to_local_dsq()

- Rename move_task_to_local_dsq() to move_remote_task_to_local_dsq().

- Rename consume_local_task() to move_local_task_to_local_dsq() and remove
  task_unlink_from_dsq() and source DSQ unlocking from it.

This is to make the migration code easier to reuse.

No functional changes intended.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David Vernet <void@manifault.com>
This commit is contained in:
Tejun Heo 2024-09-09 13:42:47 -10:00
parent d434210e13
commit cf3e94430d

View File

@ -2172,23 +2172,30 @@ static bool yield_to_task_scx(struct rq *rq, struct task_struct *to)
return false;
}
static void consume_local_task(struct task_struct *p,
struct scx_dispatch_q *dsq, struct rq *rq)
static void move_local_task_to_local_dsq(struct task_struct *p, u64 enq_flags,
struct scx_dispatch_q *src_dsq,
struct rq *dst_rq)
{
lockdep_assert_held(&dsq->lock); /* released on return */
struct scx_dispatch_q *dst_dsq = &dst_rq->scx.local_dsq;
/* @dsq is locked and @p is on @dst_rq */
lockdep_assert_held(&src_dsq->lock);
lockdep_assert_rq_held(dst_rq);
/* @dsq is locked and @p is on this rq */
WARN_ON_ONCE(p->scx.holding_cpu >= 0);
task_unlink_from_dsq(p, dsq);
list_add_tail(&p->scx.dsq_list.node, &rq->scx.local_dsq.list);
dsq_mod_nr(&rq->scx.local_dsq, 1);
p->scx.dsq = &rq->scx.local_dsq;
raw_spin_unlock(&dsq->lock);
if (enq_flags & (SCX_ENQ_HEAD | SCX_ENQ_PREEMPT))
list_add(&p->scx.dsq_list.node, &dst_dsq->list);
else
list_add_tail(&p->scx.dsq_list.node, &dst_dsq->list);
dsq_mod_nr(dst_dsq, 1);
p->scx.dsq = dst_dsq;
}
#ifdef CONFIG_SMP
/**
* move_task_to_local_dsq - Move a task from a different rq to a local DSQ
* move_remote_task_to_local_dsq - Move a task from a foreign rq to a local DSQ
* @p: task to move
* @enq_flags: %SCX_ENQ_*
* @src_rq: rq to move the task from, locked on entry, released on return
@ -2196,8 +2203,8 @@ static void consume_local_task(struct task_struct *p,
*
* Move @p which is currently on @src_rq to @dst_rq's local DSQ.
*/
static void move_task_to_local_dsq(struct task_struct *p, u64 enq_flags,
struct rq *src_rq, struct rq *dst_rq)
static void move_remote_task_to_local_dsq(struct task_struct *p, u64 enq_flags,
struct rq *src_rq, struct rq *dst_rq)
{
lockdep_assert_rq_held(src_rq);
@ -2320,7 +2327,7 @@ static bool consume_remote_task(struct rq *this_rq, struct task_struct *p,
raw_spin_rq_unlock(this_rq);
if (unlink_dsq_and_lock_src_rq(p, dsq, src_rq)) {
move_task_to_local_dsq(p, 0, src_rq, this_rq);
move_remote_task_to_local_dsq(p, 0, src_rq, this_rq);
return true;
} else {
raw_spin_rq_unlock(src_rq);
@ -2351,7 +2358,9 @@ static bool consume_dispatch_q(struct rq *rq, struct scx_dispatch_q *dsq)
struct rq *task_rq = task_rq(p);
if (rq == task_rq) {
consume_local_task(p, dsq, rq);
task_unlink_from_dsq(p, dsq);
move_local_task_to_local_dsq(p, 0, dsq, rq);
raw_spin_unlock(&dsq->lock);
return true;
}
@ -2431,13 +2440,14 @@ static void dispatch_to_local_dsq(struct rq *rq, struct scx_dispatch_q *dst_dsq,
/*
* If @p is staying on the same rq, there's no need to go
* through the full deactivate/activate cycle. Optimize by
* abbreviating the operations in move_task_to_local_dsq().
* abbreviating move_remote_task_to_local_dsq().
*/
if (src_rq == dst_rq) {
p->scx.holding_cpu = -1;
dispatch_enqueue(&dst_rq->scx.local_dsq, p, enq_flags);
} else {
move_task_to_local_dsq(p, enq_flags, src_rq, dst_rq);
move_remote_task_to_local_dsq(p, enq_flags,
src_rq, dst_rq);
}
/* if the destination CPU is idle, wake it up */