diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2024-08-14 00:25:53 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2024-09-03 15:26:31 +0200 |
| commit | fd03c5b8585562d60f8b597b4332d28f48abfe7d (patch) | |
| tree | 11b3007a752affe6beaca37c057ca9a5c0983048 /kernel/sched/idle.c | |
| parent | 260598f142c34811d226fdde5ab0346b48181439 (diff) | |
| download | linux-fd03c5b8585562d60f8b597b4332d28f48abfe7d.tar.gz linux-fd03c5b8585562d60f8b597b4332d28f48abfe7d.tar.bz2 linux-fd03c5b8585562d60f8b597b4332d28f48abfe7d.zip | |
sched: Rework pick_next_task()
The current rule is that:
pick_next_task() := pick_task() + set_next_task(.first = true)
And many classes implement it directly as such. Change things around
to make pick_next_task() optional while also changing the definition to:
pick_next_task(prev) := pick_task() + put_prev_task() + set_next_task(.first = true)
The reason is that sched_ext would like to have a 'final' call that
knows the next task. By placing put_prev_task() right next to
set_next_task() (as it already is for sched_core) this becomes
trivial.
As a bonus, this is a nice cleanup on its own.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240813224016.051225657@infradead.org
Diffstat (limited to 'kernel/sched/idle.c')
| -rw-r--r-- | kernel/sched/idle.c | 16 |
1 files changed, 2 insertions, 14 deletions
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 16074209ce26..a343e1c97f56 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -462,21 +462,10 @@ static void set_next_task_idle(struct rq *rq, struct task_struct *next, bool fir next->se.exec_start = rq_clock_task(rq); } -#ifdef CONFIG_SMP -static struct task_struct *pick_task_idle(struct rq *rq) +struct task_struct *pick_task_idle(struct rq *rq) { return rq->idle; } -#endif - -struct task_struct *pick_next_task_idle(struct rq *rq) -{ - struct task_struct *next = rq->idle; - - set_next_task_idle(rq, next, true); - - return next; -} /* * It is not legal to sleep in the idle task - print a warning @@ -531,13 +520,12 @@ DEFINE_SCHED_CLASS(idle) = { .wakeup_preempt = wakeup_preempt_idle, - .pick_next_task = pick_next_task_idle, + .pick_task = pick_task_idle, .put_prev_task = put_prev_task_idle, .set_next_task = set_next_task_idle, #ifdef CONFIG_SMP .balance = balance_idle, - .pick_task = pick_task_idle, .select_task_rq = select_task_rq_idle, .set_cpus_allowed = set_cpus_allowed_common, #endif |