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-rw-r--r--kernel/locking/mutex.c4
-rw-r--r--kernel/locking/spinlock_debug.c32
-rw-r--r--kernel/sched/cpufreq.c18
-rw-r--r--kernel/sched/cpufreq_schedutil.c8
4 files changed, 37 insertions, 25 deletions
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 54cc5f9286e9..5352ce50a97e 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -733,9 +733,6 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne
*/
void __sched mutex_unlock(struct mutex *lock)
{
-#ifdef CONFIG_DEBUG_MUTEXES
- WARN_ON(in_interrupt());
-#endif
#ifndef CONFIG_DEBUG_LOCK_ALLOC
if (__mutex_unlock_fast(lock))
return;
@@ -1416,7 +1413,6 @@ int __sched mutex_trylock(struct mutex *lock)
#ifdef CONFIG_DEBUG_MUTEXES
DEBUG_LOCKS_WARN_ON(lock->magic != lock);
- WARN_ON(in_interrupt());
#endif
locked = __mutex_trylock(lock);
diff --git a/kernel/locking/spinlock_debug.c b/kernel/locking/spinlock_debug.c
index 399669f7eba8..472dd462a40c 100644
--- a/kernel/locking/spinlock_debug.c
+++ b/kernel/locking/spinlock_debug.c
@@ -51,19 +51,19 @@ EXPORT_SYMBOL(__rwlock_init);
static void spin_dump(raw_spinlock_t *lock, const char *msg)
{
- struct task_struct *owner = NULL;
+ struct task_struct *owner = READ_ONCE(lock->owner);
- if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
- owner = lock->owner;
+ if (owner == SPINLOCK_OWNER_INIT)
+ owner = NULL;
printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
msg, raw_smp_processor_id(),
current->comm, task_pid_nr(current));
printk(KERN_EMERG " lock: %pS, .magic: %08x, .owner: %s/%d, "
".owner_cpu: %d\n",
- lock, lock->magic,
+ lock, READ_ONCE(lock->magic),
owner ? owner->comm : "<none>",
owner ? task_pid_nr(owner) : -1,
- lock->owner_cpu);
+ READ_ONCE(lock->owner_cpu));
dump_stack();
}
@@ -80,16 +80,16 @@ static void spin_bug(raw_spinlock_t *lock, const char *msg)
static inline void
debug_spin_lock_before(raw_spinlock_t *lock)
{
- SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
- SPIN_BUG_ON(lock->owner == current, lock, "recursion");
- SPIN_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
+ SPIN_BUG_ON(READ_ONCE(lock->magic) != SPINLOCK_MAGIC, lock, "bad magic");
+ SPIN_BUG_ON(READ_ONCE(lock->owner) == current, lock, "recursion");
+ SPIN_BUG_ON(READ_ONCE(lock->owner_cpu) == raw_smp_processor_id(),
lock, "cpu recursion");
}
static inline void debug_spin_lock_after(raw_spinlock_t *lock)
{
- lock->owner_cpu = raw_smp_processor_id();
- lock->owner = current;
+ WRITE_ONCE(lock->owner_cpu, raw_smp_processor_id());
+ WRITE_ONCE(lock->owner, current);
}
static inline void debug_spin_unlock(raw_spinlock_t *lock)
@@ -99,8 +99,8 @@ static inline void debug_spin_unlock(raw_spinlock_t *lock)
SPIN_BUG_ON(lock->owner != current, lock, "wrong owner");
SPIN_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
lock, "wrong CPU");
- lock->owner = SPINLOCK_OWNER_INIT;
- lock->owner_cpu = -1;
+ WRITE_ONCE(lock->owner, SPINLOCK_OWNER_INIT);
+ WRITE_ONCE(lock->owner_cpu, -1);
}
/*
@@ -187,8 +187,8 @@ static inline void debug_write_lock_before(rwlock_t *lock)
static inline void debug_write_lock_after(rwlock_t *lock)
{
- lock->owner_cpu = raw_smp_processor_id();
- lock->owner = current;
+ WRITE_ONCE(lock->owner_cpu, raw_smp_processor_id());
+ WRITE_ONCE(lock->owner, current);
}
static inline void debug_write_unlock(rwlock_t *lock)
@@ -197,8 +197,8 @@ static inline void debug_write_unlock(rwlock_t *lock)
RWLOCK_BUG_ON(lock->owner != current, lock, "wrong owner");
RWLOCK_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
lock, "wrong CPU");
- lock->owner = SPINLOCK_OWNER_INIT;
- lock->owner_cpu = -1;
+ WRITE_ONCE(lock->owner, SPINLOCK_OWNER_INIT);
+ WRITE_ONCE(lock->owner_cpu, -1);
}
void do_raw_write_lock(rwlock_t *lock)
diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c
index b5dcd1d83c7f..7c2fe50fd76d 100644
--- a/kernel/sched/cpufreq.c
+++ b/kernel/sched/cpufreq.c
@@ -5,6 +5,8 @@
* Copyright (C) 2016, Intel Corporation
* Author: Rafael J. Wysocki <[email protected]>
*/
+#include <linux/cpufreq.h>
+
#include "sched.h"
DEFINE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
@@ -57,3 +59,19 @@ void cpufreq_remove_update_util_hook(int cpu)
rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), NULL);
}
EXPORT_SYMBOL_GPL(cpufreq_remove_update_util_hook);
+
+/**
+ * cpufreq_this_cpu_can_update - Check if cpufreq policy can be updated.
+ * @policy: cpufreq policy to check.
+ *
+ * Return 'true' if:
+ * - the local and remote CPUs share @policy,
+ * - dvfs_possible_from_any_cpu is set in @policy and the local CPU is not going
+ * offline (in which case it is not expected to run cpufreq updates any more).
+ */
+bool cpufreq_this_cpu_can_update(struct cpufreq_policy *policy)
+{
+ return cpumask_test_cpu(smp_processor_id(), policy->cpus) ||
+ (policy->dvfs_possible_from_any_cpu &&
+ rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data)));
+}
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 322ca8860f54..9b8916fd00a2 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -82,12 +82,10 @@ static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time)
* by the hardware, as calculating the frequency is pointless if
* we cannot in fact act on it.
*
- * For the slow switching platforms, the kthread is always scheduled on
- * the right set of CPUs and any CPU can find the next frequency and
- * schedule the kthread.
+ * This is needed on the slow switching platforms too to prevent CPUs
+ * going offline from leaving stale IRQ work items behind.
*/
- if (sg_policy->policy->fast_switch_enabled &&
- !cpufreq_this_cpu_can_update(sg_policy->policy))
+ if (!cpufreq_this_cpu_can_update(sg_policy->policy))
return false;
if (unlikely(sg_policy->limits_changed)) {