6.6-stable review patch. If anyone has any objections, please let me know.
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From: Peter Zijlstra peterz@infradead.org
[ Upstream commit 6fb45460615358157a6d3c990e74f9c1395247e2 ]
Use guards to reduce gotos and simplify control flow.
Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Signed-off-by: Ingo Molnar mingo@kernel.org Stable-dep-of: 1aa09b9379a7 ("powercap: intel_rapl: Fix locking in TPMI RAPL") Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/cpu.h | 2 ++ kernel/sched/core.c | 38 +++++++++++++++++++------------------- 2 files changed, 21 insertions(+), 19 deletions(-)
diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 59dd421a8e35d..e990c180282e7 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -157,6 +157,8 @@ static inline int remove_cpu(unsigned int cpu) { return -EPERM; } static inline void smp_shutdown_nonboot_cpus(unsigned int primary_cpu) { } #endif /* !CONFIG_HOTPLUG_CPU */
+DEFINE_LOCK_GUARD_0(cpus_read_lock, cpus_read_lock(), cpus_read_unlock()) + #ifdef CONFIG_PM_SLEEP_SMP extern int freeze_secondary_cpus(int primary); extern void thaw_secondary_cpus(void); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a854b71836dd5..1f91e2c12731e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -10868,11 +10868,12 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota, * Prevent race between setting of cfs_rq->runtime_enabled and * unthrottle_offline_cfs_rqs(). */ - cpus_read_lock(); - mutex_lock(&cfs_constraints_mutex); + guard(cpus_read_lock)(); + guard(mutex)(&cfs_constraints_mutex); + ret = __cfs_schedulable(tg, period, quota); if (ret) - goto out_unlock; + return ret;
runtime_enabled = quota != RUNTIME_INF; runtime_was_enabled = cfs_b->quota != RUNTIME_INF; @@ -10882,39 +10883,38 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota, */ if (runtime_enabled && !runtime_was_enabled) cfs_bandwidth_usage_inc(); - raw_spin_lock_irq(&cfs_b->lock); - cfs_b->period = ns_to_ktime(period); - cfs_b->quota = quota; - cfs_b->burst = burst;
- __refill_cfs_bandwidth_runtime(cfs_b); + scoped_guard (raw_spinlock_irq, &cfs_b->lock) { + cfs_b->period = ns_to_ktime(period); + cfs_b->quota = quota; + cfs_b->burst = burst;
- /* Restart the period timer (if active) to handle new period expiry: */ - if (runtime_enabled) - start_cfs_bandwidth(cfs_b); + __refill_cfs_bandwidth_runtime(cfs_b);
- raw_spin_unlock_irq(&cfs_b->lock); + /* + * Restart the period timer (if active) to handle new + * period expiry: + */ + if (runtime_enabled) + start_cfs_bandwidth(cfs_b); + }
for_each_online_cpu(i) { struct cfs_rq *cfs_rq = tg->cfs_rq[i]; struct rq *rq = cfs_rq->rq; - struct rq_flags rf;
- rq_lock_irq(rq, &rf); + guard(rq_lock_irq)(rq); cfs_rq->runtime_enabled = runtime_enabled; cfs_rq->runtime_remaining = 0;
if (cfs_rq->throttled) unthrottle_cfs_rq(cfs_rq); - rq_unlock_irq(rq, &rf); } + if (runtime_was_enabled && !runtime_enabled) cfs_bandwidth_usage_dec(); -out_unlock: - mutex_unlock(&cfs_constraints_mutex); - cpus_read_unlock();
- return ret; + return 0; }
static int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us)