[tip:,sched/core] sched: Simplify sched_core_cpu_{starting,deactivate}()
Commit Message
The following commit has been merged into the sched/core branch of tip:
Commit-ID: 7170509cadbb76e5fa7d7b090d2cbdb93d56a2de
Gitweb: https://git.kernel.org/tip/7170509cadbb76e5fa7d7b090d2cbdb93d56a2de
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Tue, 01 Aug 2023 22:41:30 +02:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Mon, 14 Aug 2023 17:01:27 +02:00
sched: Simplify sched_core_cpu_{starting,deactivate}()
Use guards to reduce gotos and simplify control flow.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lore.kernel.org/r/20230801211812.371787909@infradead.org
---
kernel/sched/core.c | 27 ++++++++++++---------------
1 file changed, 12 insertions(+), 15 deletions(-)
@@ -6400,20 +6400,24 @@ static void queue_core_balance(struct rq *rq)
queue_balance_callback(rq, &per_cpu(core_balance_head, rq->cpu), sched_core_balance);
}
+DEFINE_LOCK_GUARD_1(core_lock, int,
+ sched_core_lock(*_T->lock, &_T->flags),
+ sched_core_unlock(*_T->lock, &_T->flags),
+ unsigned long flags)
+
static void sched_core_cpu_starting(unsigned int cpu)
{
const struct cpumask *smt_mask = cpu_smt_mask(cpu);
struct rq *rq = cpu_rq(cpu), *core_rq = NULL;
- unsigned long flags;
int t;
- sched_core_lock(cpu, &flags);
+ guard(core_lock)(&cpu);
WARN_ON_ONCE(rq->core != rq);
/* if we're the first, we'll be our own leader */
if (cpumask_weight(smt_mask) == 1)
- goto unlock;
+ return;
/* find the leader */
for_each_cpu(t, smt_mask) {
@@ -6427,7 +6431,7 @@ static void sched_core_cpu_starting(unsigned int cpu)
}
if (WARN_ON_ONCE(!core_rq)) /* whoopsie */
- goto unlock;
+ return;
/* install and validate core_rq */
for_each_cpu(t, smt_mask) {
@@ -6438,29 +6442,25 @@ static void sched_core_cpu_starting(unsigned int cpu)
WARN_ON_ONCE(rq->core != core_rq);
}
-
-unlock:
- sched_core_unlock(cpu, &flags);
}
static void sched_core_cpu_deactivate(unsigned int cpu)
{
const struct cpumask *smt_mask = cpu_smt_mask(cpu);
struct rq *rq = cpu_rq(cpu), *core_rq = NULL;
- unsigned long flags;
int t;
- sched_core_lock(cpu, &flags);
+ guard(core_lock)(&cpu);
/* if we're the last man standing, nothing to do */
if (cpumask_weight(smt_mask) == 1) {
WARN_ON_ONCE(rq->core != rq);
- goto unlock;
+ return;
}
/* if we're not the leader, nothing to do */
if (rq->core != rq)
- goto unlock;
+ return;
/* find a new leader */
for_each_cpu(t, smt_mask) {
@@ -6471,7 +6471,7 @@ static void sched_core_cpu_deactivate(unsigned int cpu)
}
if (WARN_ON_ONCE(!core_rq)) /* impossible */
- goto unlock;
+ return;
/* copy the shared state to the new leader */
core_rq->core_task_seq = rq->core_task_seq;
@@ -6493,9 +6493,6 @@ static void sched_core_cpu_deactivate(unsigned int cpu)
rq = cpu_rq(t);
rq->core = core_rq;
}
-
-unlock:
- sched_core_unlock(cpu, &flags);
}
static inline void sched_core_cpu_dying(unsigned int cpu)