From de6a97ce42aca8cecb64fc5e151dd23a1c5a0447 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Sun, 27 Jan 2008 19:54:46 -0500 Subject: [PATCH] mips: Implement down_killable Signed-off-by: Matthew Wilcox --- arch/mips/kernel/semaphore.c | 32 ++++++++++++++++++++++++++++++++ include/asm-mips/semaphore.h | 12 ++++++++++++ 2 files changed, 44 insertions(+), 0 deletions(-) diff --git a/arch/mips/kernel/semaphore.c b/arch/mips/kernel/semaphore.c index 1265358..6505de5 100644 --- a/arch/mips/kernel/semaphore.c +++ b/arch/mips/kernel/semaphore.c @@ -166,3 +166,35 @@ int __sched __down_interruptible(struct semaphore * sem) } EXPORT_SYMBOL(__down_interruptible); + +int __sched __down_killable(struct semaphore * sem) +{ + int retval = 0; + struct task_struct *tsk = current; + DECLARE_WAITQUEUE(wait, tsk); + + __set_task_state(tsk, TASK_KILLABLE); + add_wait_queue_exclusive(&sem->wait, &wait); + + while (__sem_update_count(sem, -1) <= 0) { + if (fatal_signal_pending(current)) { + /* + * A signal is pending - give up trying. + * Set sem->count to 0 if it is negative, + * since we are no longer sleeping. + */ + __sem_update_count(sem, 0); + retval = -EINTR; + break; + } + schedule(); + set_task_state(tsk, TASK_KILLABLE); + } + remove_wait_queue(&sem->wait, &wait); + __set_task_state(tsk, TASK_RUNNING); + + wake_up(&sem->wait); + return retval; +} + +EXPORT_SYMBOL(__down_killable); diff --git a/include/asm-mips/semaphore.h b/include/asm-mips/semaphore.h index fdf8042..a5ef708 100644 --- a/include/asm-mips/semaphore.h +++ b/include/asm-mips/semaphore.h @@ -68,6 +68,7 @@ static inline void init_MUTEX_LOCKED(struct semaphore *sem) extern void __down(struct semaphore * sem); extern int __down_interruptible(struct semaphore * sem); +extern int __down_killable(struct semaphore * sem); extern void __up(struct semaphore * sem); static inline void down(struct semaphore * sem) @@ -92,6 +93,17 @@ static inline int down_interruptible(struct semaphore * sem) return ret; } +static inline int down_killable(struct semaphore * sem) +{ + int ret = 0; + + might_sleep(); + + if (unlikely(atomic_dec_return(&sem->count) < 0)) + ret = __down_killable(sem); + return ret; +} + static inline int down_trylock(struct semaphore * sem) { return atomic_dec_if_positive(&sem->count) < 0; -- 1.5.3.8