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-rw-r--r--kernel/locking/lockdep.c39
-rw-r--r--kernel/locking/lockdep_internals.h18
-rw-r--r--kernel/locking/lockdep_proc.c2
-rw-r--r--kernel/locking/mutex-debug.c9
-rw-r--r--kernel/locking/mutex.c48
-rw-r--r--kernel/locking/mutex.h3
-rw-r--r--kernel/locking/rtmutex_api.c51
-rw-r--r--kernel/locking/rwsem.c4
-rw-r--r--kernel/locking/semaphore.c57
-rw-r--r--kernel/locking/ww_mutex.h16
10 files changed, 181 insertions, 66 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index dd2bbf73718b..2d4c5bab5af8 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -297,33 +297,30 @@ static inline void lock_time_add(struct lock_time *src, struct lock_time *dst)
dst->nr += src->nr;
}
-struct lock_class_stats lock_stats(struct lock_class *class)
+void lock_stats(struct lock_class *class, struct lock_class_stats *stats)
{
- struct lock_class_stats stats;
int cpu, i;
- memset(&stats, 0, sizeof(struct lock_class_stats));
+ memset(stats, 0, sizeof(struct lock_class_stats));
for_each_possible_cpu(cpu) {
struct lock_class_stats *pcs =
&per_cpu(cpu_lock_stats, cpu)[class - lock_classes];
- for (i = 0; i < ARRAY_SIZE(stats.contention_point); i++)
- stats.contention_point[i] += pcs->contention_point[i];
+ for (i = 0; i < ARRAY_SIZE(stats->contention_point); i++)
+ stats->contention_point[i] += pcs->contention_point[i];
- for (i = 0; i < ARRAY_SIZE(stats.contending_point); i++)
- stats.contending_point[i] += pcs->contending_point[i];
+ for (i = 0; i < ARRAY_SIZE(stats->contending_point); i++)
+ stats->contending_point[i] += pcs->contending_point[i];
- lock_time_add(&pcs->read_waittime, &stats.read_waittime);
- lock_time_add(&pcs->write_waittime, &stats.write_waittime);
+ lock_time_add(&pcs->read_waittime, &stats->read_waittime);
+ lock_time_add(&pcs->write_waittime, &stats->write_waittime);
- lock_time_add(&pcs->read_holdtime, &stats.read_holdtime);
- lock_time_add(&pcs->write_holdtime, &stats.write_holdtime);
+ lock_time_add(&pcs->read_holdtime, &stats->read_holdtime);
+ lock_time_add(&pcs->write_holdtime, &stats->write_holdtime);
- for (i = 0; i < ARRAY_SIZE(stats.bounces); i++)
- stats.bounces[i] += pcs->bounces[i];
+ for (i = 0; i < ARRAY_SIZE(stats->bounces); i++)
+ stats->bounces[i] += pcs->bounces[i];
}
-
- return stats;
}
void clear_lock_stats(struct lock_class *class)
@@ -6619,8 +6616,16 @@ void lockdep_unregister_key(struct lock_class_key *key)
if (need_callback)
call_rcu(&delayed_free.rcu_head, free_zapped_rcu);
- /* Wait until is_dynamic_key() has finished accessing k->hash_entry. */
- synchronize_rcu();
+ /*
+ * Wait until is_dynamic_key() has finished accessing k->hash_entry.
+ *
+ * Some operations like __qdisc_destroy() will call this in a debug
+ * kernel, and the network traffic is disabled while waiting, hence
+ * the delay of the wait matters in debugging cases. Currently use a
+ * synchronize_rcu_expedited() to speed up the wait at the cost of
+ * system IPIs. TODO: Replace RCU with hazptr for this.
+ */
+ synchronize_rcu_expedited();
}
EXPORT_SYMBOL_GPL(lockdep_unregister_key);
diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h
index 82156caf77d1..0e5e6ffe91a3 100644
--- a/kernel/locking/lockdep_internals.h
+++ b/kernel/locking/lockdep_internals.h
@@ -47,29 +47,31 @@ enum {
__LOCKF(USED_READ)
};
+enum {
#define LOCKDEP_STATE(__STATE) LOCKF_ENABLED_##__STATE |
-static const unsigned long LOCKF_ENABLED_IRQ =
+ LOCKF_ENABLED_IRQ =
#include "lockdep_states.h"
- 0;
+ 0,
#undef LOCKDEP_STATE
#define LOCKDEP_STATE(__STATE) LOCKF_USED_IN_##__STATE |
-static const unsigned long LOCKF_USED_IN_IRQ =
+ LOCKF_USED_IN_IRQ =
#include "lockdep_states.h"
- 0;
+ 0,
#undef LOCKDEP_STATE
#define LOCKDEP_STATE(__STATE) LOCKF_ENABLED_##__STATE##_READ |
-static const unsigned long LOCKF_ENABLED_IRQ_READ =
+ LOCKF_ENABLED_IRQ_READ =
#include "lockdep_states.h"
- 0;
+ 0,
#undef LOCKDEP_STATE
#define LOCKDEP_STATE(__STATE) LOCKF_USED_IN_##__STATE##_READ |
-static const unsigned long LOCKF_USED_IN_IRQ_READ =
+ LOCKF_USED_IN_IRQ_READ =
#include "lockdep_states.h"
- 0;
+ 0,
#undef LOCKDEP_STATE
+};
#define LOCKF_ENABLED_IRQ_ALL (LOCKF_ENABLED_IRQ | LOCKF_ENABLED_IRQ_READ)
#define LOCKF_USED_IN_IRQ_ALL (LOCKF_USED_IN_IRQ | LOCKF_USED_IN_IRQ_READ)
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c
index b52c07c4707c..1916db9aa46b 100644
--- a/kernel/locking/lockdep_proc.c
+++ b/kernel/locking/lockdep_proc.c
@@ -657,7 +657,7 @@ static int lock_stat_open(struct inode *inode, struct file *file)
if (!test_bit(idx, lock_classes_in_use))
continue;
iter->class = class;
- iter->stats = lock_stats(class);
+ lock_stats(class, &iter->stats);
iter++;
}
diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
index 6e6f6071cfa2..949103fd8e9b 100644
--- a/kernel/locking/mutex-debug.c
+++ b/kernel/locking/mutex-debug.c
@@ -53,17 +53,18 @@ void debug_mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter,
{
lockdep_assert_held(&lock->wait_lock);
- /* Mark the current thread as blocked on the lock: */
- task->blocked_on = waiter;
+ /* Current thread can't be already blocked (since it's executing!) */
+ DEBUG_LOCKS_WARN_ON(__get_task_blocked_on(task));
}
void debug_mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
struct task_struct *task)
{
+ struct mutex *blocked_on = __get_task_blocked_on(task);
+
DEBUG_LOCKS_WARN_ON(list_empty(&waiter->list));
DEBUG_LOCKS_WARN_ON(waiter->task != task);
- DEBUG_LOCKS_WARN_ON(task->blocked_on != waiter);
- task->blocked_on = NULL;
+ DEBUG_LOCKS_WARN_ON(blocked_on && blocked_on != lock);
INIT_LIST_HEAD(&waiter->list);
waiter->task = NULL;
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 555e2b3a665a..de7d6702cd96 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -29,6 +29,7 @@
#include <linux/interrupt.h>
#include <linux/debug_locks.h>
#include <linux/osq_lock.h>
+#include <linux/hung_task.h>
#define CREATE_TRACE_POINTS
#include <trace/events/lock.h>
@@ -190,9 +191,7 @@ static void
__mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter,
struct list_head *list)
{
-#ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER
- WRITE_ONCE(current->blocker_mutex, lock);
-#endif
+ hung_task_set_blocker(lock, BLOCKER_TYPE_MUTEX);
debug_mutex_add_waiter(lock, waiter, current);
list_add_tail(&waiter->list, list);
@@ -208,9 +207,7 @@ __mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter)
__mutex_clear_flag(lock, MUTEX_FLAGS);
debug_mutex_remove_waiter(lock, waiter, current);
-#ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER
- WRITE_ONCE(current->blocker_mutex, NULL);
-#endif
+ hung_task_clear_blocker();
}
/*
@@ -643,6 +640,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
goto err_early_kill;
}
+ __set_task_blocked_on(current, lock);
set_current_state(state);
trace_contention_begin(lock, LCB_F_MUTEX);
for (;;) {
@@ -679,6 +677,12 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
first = __mutex_waiter_is_first(lock, &waiter);
+ /*
+ * As we likely have been woken up by task
+ * that has cleared our blocked_on state, re-set
+ * it to the lock we are trying to acquire.
+ */
+ set_task_blocked_on(current, lock);
set_current_state(state);
/*
* Here we order against unlock; we must either see it change
@@ -690,8 +694,15 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
if (first) {
trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN);
+ /*
+ * mutex_optimistic_spin() can call schedule(), so
+ * clear blocked on so we don't become unselectable
+ * to run.
+ */
+ clear_task_blocked_on(current, lock);
if (mutex_optimistic_spin(lock, ww_ctx, &waiter))
break;
+ set_task_blocked_on(current, lock);
trace_contention_begin(lock, LCB_F_MUTEX);
}
@@ -699,6 +710,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
}
raw_spin_lock_irqsave(&lock->wait_lock, flags);
acquired:
+ __clear_task_blocked_on(current, lock);
__set_current_state(TASK_RUNNING);
if (ww_ctx) {
@@ -728,9 +740,11 @@ skip_wait:
return 0;
err:
+ __clear_task_blocked_on(current, lock);
__set_current_state(TASK_RUNNING);
__mutex_remove_waiter(lock, &waiter);
err_early_kill:
+ WARN_ON(__get_task_blocked_on(current));
trace_contention_end(lock, ret);
raw_spin_unlock_irqrestore_wake(&lock->wait_lock, flags, &wake_q);
debug_mutex_free_waiter(&waiter);
@@ -808,11 +822,12 @@ _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest)
EXPORT_SYMBOL_GPL(_mutex_lock_nest_lock);
int __sched
-mutex_lock_killable_nested(struct mutex *lock, unsigned int subclass)
+_mutex_lock_killable(struct mutex *lock, unsigned int subclass,
+ struct lockdep_map *nest)
{
- return __mutex_lock(lock, TASK_KILLABLE, subclass, NULL, _RET_IP_);
+ return __mutex_lock(lock, TASK_KILLABLE, subclass, nest, _RET_IP_);
}
-EXPORT_SYMBOL_GPL(mutex_lock_killable_nested);
+EXPORT_SYMBOL_GPL(_mutex_lock_killable);
int __sched
mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass)
@@ -940,6 +955,7 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne
next = waiter->task;
debug_mutex_wake_waiter(lock, waiter);
+ __clear_task_blocked_on(next, lock);
wake_q_add(&wake_q, next);
}
@@ -1062,6 +1078,7 @@ __ww_mutex_lock_interruptible_slowpath(struct ww_mutex *lock,
#endif
+#ifndef CONFIG_DEBUG_LOCK_ALLOC
/**
* mutex_trylock - try to acquire the mutex, without waiting
* @lock: the mutex to be acquired
@@ -1078,17 +1095,24 @@ __ww_mutex_lock_interruptible_slowpath(struct ww_mutex *lock,
*/
int __sched mutex_trylock(struct mutex *lock)
{
+ MUTEX_WARN_ON(lock->magic != lock);
+ return __mutex_trylock(lock);
+}
+EXPORT_SYMBOL(mutex_trylock);
+#else
+int __sched _mutex_trylock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock)
+{
bool locked;
MUTEX_WARN_ON(lock->magic != lock);
-
locked = __mutex_trylock(lock);
if (locked)
- mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+ mutex_acquire_nest(&lock->dep_map, 0, 1, nest_lock, _RET_IP_);
return locked;
}
-EXPORT_SYMBOL(mutex_trylock);
+EXPORT_SYMBOL(_mutex_trylock_nest_lock);
+#endif
#ifndef CONFIG_DEBUG_LOCK_ALLOC
int __sched
diff --git a/kernel/locking/mutex.h b/kernel/locking/mutex.h
index cbff35b9b7ae..2e8080a9bee3 100644
--- a/kernel/locking/mutex.h
+++ b/kernel/locking/mutex.h
@@ -6,7 +6,7 @@
*
* Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
*/
-
+#ifndef CONFIG_PREEMPT_RT
/*
* This is the control structure for tasks blocked on mutex, which resides
* on the blocked task's kernel stack:
@@ -70,3 +70,4 @@ extern void debug_mutex_init(struct mutex *lock, const char *name,
# define debug_mutex_unlock(lock) do { } while (0)
# define debug_mutex_init(lock, name, key) do { } while (0)
#endif /* !CONFIG_DEBUG_MUTEXES */
+#endif /* CONFIG_PREEMPT_RT */
diff --git a/kernel/locking/rtmutex_api.c b/kernel/locking/rtmutex_api.c
index 191e4720e546..bafd5af98eae 100644
--- a/kernel/locking/rtmutex_api.c
+++ b/kernel/locking/rtmutex_api.c
@@ -13,6 +13,24 @@
*/
int max_lock_depth = 1024;
+static const struct ctl_table rtmutex_sysctl_table[] = {
+ {
+ .procname = "max_lock_depth",
+ .data = &max_lock_depth,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+};
+
+static int __init init_rtmutex_sysctl(void)
+{
+ register_sysctl_init("kernel", rtmutex_sysctl_table);
+ return 0;
+}
+
+subsys_initcall(init_rtmutex_sysctl);
+
/*
* Debug aware fast / slowpath lock,trylock,unlock
*
@@ -544,12 +562,12 @@ int __sched mutex_lock_interruptible_nested(struct mutex *lock,
}
EXPORT_SYMBOL_GPL(mutex_lock_interruptible_nested);
-int __sched mutex_lock_killable_nested(struct mutex *lock,
- unsigned int subclass)
+int __sched _mutex_lock_killable(struct mutex *lock, unsigned int subclass,
+ struct lockdep_map *nest_lock)
{
- return __mutex_lock_common(lock, TASK_KILLABLE, subclass, NULL, _RET_IP_);
+ return __mutex_lock_common(lock, TASK_KILLABLE, subclass, nest_lock, _RET_IP_);
}
-EXPORT_SYMBOL_GPL(mutex_lock_killable_nested);
+EXPORT_SYMBOL_GPL(_mutex_lock_killable);
void __sched mutex_lock_io_nested(struct mutex *lock, unsigned int subclass)
{
@@ -563,6 +581,21 @@ void __sched mutex_lock_io_nested(struct mutex *lock, unsigned int subclass)
}
EXPORT_SYMBOL_GPL(mutex_lock_io_nested);
+int __sched _mutex_trylock_nest_lock(struct mutex *lock,
+ struct lockdep_map *nest_lock)
+{
+ int ret;
+
+ if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task()))
+ return 0;
+
+ ret = __rt_mutex_trylock(&lock->rtmutex);
+ if (ret)
+ mutex_acquire_nest(&lock->dep_map, 0, 1, nest_lock, _RET_IP_);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(_mutex_trylock_nest_lock);
#else /* CONFIG_DEBUG_LOCK_ALLOC */
void __sched mutex_lock(struct mutex *lock)
@@ -591,22 +624,16 @@ void __sched mutex_lock_io(struct mutex *lock)
io_schedule_finish(token);
}
EXPORT_SYMBOL(mutex_lock_io);
-#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
int __sched mutex_trylock(struct mutex *lock)
{
- int ret;
-
if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task()))
return 0;
- ret = __rt_mutex_trylock(&lock->rtmutex);
- if (ret)
- mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
-
- return ret;
+ return __rt_mutex_trylock(&lock->rtmutex);
}
EXPORT_SYMBOL(mutex_trylock);
+#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
void __sched mutex_unlock(struct mutex *lock)
{
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index 2ddb827e3bea..8572dba95af4 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -727,8 +727,6 @@ static inline bool rwsem_can_spin_on_owner(struct rw_semaphore *sem)
return ret;
}
-#define OWNER_SPINNABLE (OWNER_NULL | OWNER_WRITER | OWNER_READER)
-
static inline enum owner_state
rwsem_owner_state(struct task_struct *owner, unsigned long flags)
{
@@ -835,7 +833,7 @@ static bool rwsem_optimistic_spin(struct rw_semaphore *sem)
enum owner_state owner_state;
owner_state = rwsem_spin_on_owner(sem);
- if (!(owner_state & OWNER_SPINNABLE))
+ if (owner_state == OWNER_NONSPINNABLE)
break;
/*
diff --git a/kernel/locking/semaphore.c b/kernel/locking/semaphore.c
index de9117c0e671..3ef032e22f7e 100644
--- a/kernel/locking/semaphore.c
+++ b/kernel/locking/semaphore.c
@@ -34,6 +34,7 @@
#include <linux/spinlock.h>
#include <linux/ftrace.h>
#include <trace/events/lock.h>
+#include <linux/hung_task.h>
static noinline void __down(struct semaphore *sem);
static noinline int __down_interruptible(struct semaphore *sem);
@@ -41,6 +42,41 @@ static noinline int __down_killable(struct semaphore *sem);
static noinline int __down_timeout(struct semaphore *sem, long timeout);
static noinline void __up(struct semaphore *sem, struct wake_q_head *wake_q);
+#ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER
+static inline void hung_task_sem_set_holder(struct semaphore *sem)
+{
+ WRITE_ONCE((sem)->last_holder, (unsigned long)current);
+}
+
+static inline void hung_task_sem_clear_if_holder(struct semaphore *sem)
+{
+ if (READ_ONCE((sem)->last_holder) == (unsigned long)current)
+ WRITE_ONCE((sem)->last_holder, 0UL);
+}
+
+unsigned long sem_last_holder(struct semaphore *sem)
+{
+ return READ_ONCE(sem->last_holder);
+}
+#else
+static inline void hung_task_sem_set_holder(struct semaphore *sem)
+{
+}
+static inline void hung_task_sem_clear_if_holder(struct semaphore *sem)
+{
+}
+unsigned long sem_last_holder(struct semaphore *sem)
+{
+ return 0UL;
+}
+#endif
+
+static inline void __sem_acquire(struct semaphore *sem)
+{
+ sem->count--;
+ hung_task_sem_set_holder(sem);
+}
+
/**
* down - acquire the semaphore
* @sem: the semaphore to be acquired
@@ -59,7 +95,7 @@ void __sched down(struct semaphore *sem)
might_sleep();
raw_spin_lock_irqsave(&sem->lock, flags);
if (likely(sem->count > 0))
- sem->count--;
+ __sem_acquire(sem);
else
__down(sem);
raw_spin_unlock_irqrestore(&sem->lock, flags);
@@ -83,7 +119,7 @@ int __sched down_interruptible(struct semaphore *sem)
might_sleep();
raw_spin_lock_irqsave(&sem->lock, flags);
if (likely(sem->count > 0))
- sem->count--;
+ __sem_acquire(sem);
else
result = __down_interruptible(sem);
raw_spin_unlock_irqrestore(&sem->lock, flags);
@@ -110,7 +146,7 @@ int __sched down_killable(struct semaphore *sem)
might_sleep();
raw_spin_lock_irqsave(&sem->lock, flags);
if (likely(sem->count > 0))
- sem->count--;
+ __sem_acquire(sem);
else
result = __down_killable(sem);
raw_spin_unlock_irqrestore(&sem->lock, flags);
@@ -140,7 +176,7 @@ int __sched down_trylock(struct semaphore *sem)
raw_spin_lock_irqsave(&sem->lock, flags);
count = sem->count - 1;
if (likely(count >= 0))
- sem->count = count;
+ __sem_acquire(sem);
raw_spin_unlock_irqrestore(&sem->lock, flags);
return (count < 0);
@@ -165,7 +201,7 @@ int __sched down_timeout(struct semaphore *sem, long timeout)
might_sleep();
raw_spin_lock_irqsave(&sem->lock, flags);
if (likely(sem->count > 0))
- sem->count--;
+ __sem_acquire(sem);
else
result = __down_timeout(sem, timeout);
raw_spin_unlock_irqrestore(&sem->lock, flags);
@@ -187,6 +223,9 @@ void __sched up(struct semaphore *sem)
DEFINE_WAKE_Q(wake_q);
raw_spin_lock_irqsave(&sem->lock, flags);
+
+ hung_task_sem_clear_if_holder(sem);
+
if (likely(list_empty(&sem->wait_list)))
sem->count++;
else
@@ -228,8 +267,10 @@ static inline int __sched ___down_common(struct semaphore *sem, long state,
raw_spin_unlock_irq(&sem->lock);
timeout = schedule_timeout(timeout);
raw_spin_lock_irq(&sem->lock);
- if (waiter.up)
+ if (waiter.up) {
+ hung_task_sem_set_holder(sem);
return 0;
+ }
}
timed_out:
@@ -246,10 +287,14 @@ static inline int __sched __down_common(struct semaphore *sem, long state,
{
int ret;
+ hung_task_set_blocker(sem, BLOCKER_TYPE_SEM);
+
trace_contention_begin(sem, 0);
ret = ___down_common(sem, state, timeout);
trace_contention_end(sem, ret);
+ hung_task_clear_blocker();
+
return ret;
}
diff --git a/kernel/locking/ww_mutex.h b/kernel/locking/ww_mutex.h
index 37f025a096c9..086fd5487ca7 100644
--- a/kernel/locking/ww_mutex.h
+++ b/kernel/locking/ww_mutex.h
@@ -284,6 +284,12 @@ __ww_mutex_die(struct MUTEX *lock, struct MUTEX_WAITER *waiter,
#ifndef WW_RT
debug_mutex_wake_waiter(lock, waiter);
#endif
+ /*
+ * When waking up the task to die, be sure to clear the
+ * blocked_on pointer. Otherwise we can see circular
+ * blocked_on relationships that can't resolve.
+ */
+ __clear_task_blocked_on(waiter->task, lock);
wake_q_add(wake_q, waiter->task);
}
@@ -331,9 +337,15 @@ static bool __ww_mutex_wound(struct MUTEX *lock,
* it's wounded in __ww_mutex_check_kill() or has a
* wakeup pending to re-read the wounded state.
*/
- if (owner != current)
+ if (owner != current) {
+ /*
+ * When waking up the task to wound, be sure to clear the
+ * blocked_on pointer. Otherwise we can see circular
+ * blocked_on relationships that can't resolve.
+ */
+ __clear_task_blocked_on(owner, lock);
wake_q_add(wake_q, owner);
-
+ }
return true;
}
generated by cgit (git 2.34.1) at 2025-08-02 16:52:13 +0000