From ad776537cc6b4b936cfd11893e7b698dfa072666 Mon Sep 17 00:00:00 2001 From: "Liam R. Howlett" Date: Thu, 6 Dec 2007 17:37:59 -0500 Subject: [PATCH] Add mutex_lock_killable Similar to mutex_lock_interruptible, it can be interrupted by a fatal signal only. Signed-off-by: Liam R. Howlett Acked-by: Ingo Molnar Signed-off-by: Matthew Wilcox --- include/linux/mutex.h | 5 +++++ kernel/mutex.c | 36 +++++++++++++++++++++++++++++++++--- 2 files changed, 38 insertions(+), 3 deletions(-) diff --git a/include/linux/mutex.h b/include/linux/mutex.h index 6014797..05c5903 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -125,15 +125,20 @@ static inline int fastcall mutex_is_locked(struct mutex *lock) extern void mutex_lock_nested(struct mutex *lock, unsigned int subclass); extern int __must_check mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass); +extern int __must_check mutex_lock_killable_nested(struct mutex *lock, + unsigned int subclass); #define mutex_lock(lock) mutex_lock_nested(lock, 0) #define mutex_lock_interruptible(lock) mutex_lock_interruptible_nested(lock, 0) +#define mutex_lock_killable(lock) mutex_lock_killable_nested(lock, 0) #else extern void fastcall mutex_lock(struct mutex *lock); extern int __must_check fastcall mutex_lock_interruptible(struct mutex *lock); +extern int __must_check fastcall mutex_lock_killable(struct mutex *lock); # define mutex_lock_nested(lock, subclass) mutex_lock(lock) # define mutex_lock_interruptible_nested(lock, subclass) mutex_lock_interruptible(lock) +# define mutex_lock_killable_nested(lock, subclass) mutex_lock_killable(lock) #endif /* diff --git a/kernel/mutex.c b/kernel/mutex.c index d7fe50c..d9ec9b6 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -166,9 +166,12 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, * got a signal? (This code gets eliminated in the * TASK_UNINTERRUPTIBLE case.) */ - if (unlikely(state == TASK_INTERRUPTIBLE && - signal_pending(task))) { - mutex_remove_waiter(lock, &waiter, task_thread_info(task)); + if (unlikely((state == TASK_INTERRUPTIBLE && + signal_pending(task)) || + (state == TASK_KILLABLE && + fatal_signal_pending(task)))) { + mutex_remove_waiter(lock, &waiter, + task_thread_info(task)); mutex_release(&lock->dep_map, 1, ip); spin_unlock_mutex(&lock->wait_lock, flags); @@ -211,6 +214,14 @@ mutex_lock_nested(struct mutex *lock, unsigned int subclass) EXPORT_SYMBOL_GPL(mutex_lock_nested); int __sched +mutex_lock_killable_nested(struct mutex *lock, unsigned int subclass) +{ + might_sleep(); + return __mutex_lock_common(lock, TASK_KILLABLE, subclass, _RET_IP_); +} +EXPORT_SYMBOL_GPL(mutex_lock_killable_nested); + +int __sched mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass) { might_sleep(); @@ -272,6 +283,9 @@ __mutex_unlock_slowpath(atomic_t *lock_count) * mutex_lock_interruptible() and mutex_trylock(). */ static int fastcall noinline __sched +__mutex_lock_killable_slowpath(atomic_t *lock_count); + +static noinline int fastcall __sched __mutex_lock_interruptible_slowpath(atomic_t *lock_count); /*** @@ -294,6 +308,14 @@ int fastcall __sched mutex_lock_interruptible(struct mutex *lock) EXPORT_SYMBOL(mutex_lock_interruptible); +int fastcall __sched mutex_lock_killable(struct mutex *lock) +{ + might_sleep(); + return __mutex_fastpath_lock_retval + (&lock->count, __mutex_lock_killable_slowpath); +} +EXPORT_SYMBOL(mutex_lock_killable); + static void fastcall noinline __sched __mutex_lock_slowpath(atomic_t *lock_count) { @@ -303,6 +325,14 @@ __mutex_lock_slowpath(atomic_t *lock_count) } static int fastcall noinline __sched +__mutex_lock_killable_slowpath(atomic_t *lock_count) +{ + struct mutex *lock = container_of(lock_count, struct mutex, count); + + return __mutex_lock_common(lock, TASK_KILLABLE, 0, _RET_IP_); +} + +static noinline int fastcall __sched __mutex_lock_interruptible_slowpath(atomic_t *lock_count) { struct mutex *lock = container_of(lock_count, struct mutex, count); -- 2.7.4