From 8b91de2e58318d1168bc13d164478c1a7217a63a Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 26 Feb 2008 09:53:20 -0500 Subject: Fix quota.h includes quota.h currently relies on asm/semaphore.h (through some chain; it doesn't actually include semaphore.h itself) to include wait.h. As well as being bad practice to rely on an implicit include, subsequent patches will break this. While I'm in this file, add atomic.h and list.h, and sort the list of includes. Signed-off-by: Matthew Wilcox --- include/linux/quota.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/quota.h b/include/linux/quota.h index 6e0393a5b2ea..eb560d031acd 100644 --- a/include/linux/quota.h +++ b/include/linux/quota.h @@ -160,14 +160,18 @@ enum { #ifdef __KERNEL__ -#include -#include +#include #include +#include +#include +#include #include #include #include +#include + extern spinlock_t dq_data_lock; /* Maximal numbers of writes for quota operation (insert/delete/update) -- cgit v1.2.3 From 64ac24e738823161693bf791f87adc802cf529ff Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 7 Mar 2008 21:55:58 -0500 Subject: Generic semaphore implementation Semaphores are no longer performance-critical, so a generic C implementation is better for maintainability, debuggability and extensibility. Thanks to Peter Zijlstra for fixing the lockdep warning. Thanks to Harvey Harrison for pointing out that the unlikely() was unnecessary. Signed-off-by: Matthew Wilcox Acked-by: Ingo Molnar --- include/asm-alpha/semaphore.h | 150 +----------------------- include/asm-arm/semaphore-helper.h | 84 -------------- include/asm-arm/semaphore.h | 99 +--------------- include/asm-avr32/semaphore.h | 109 +---------------- include/asm-blackfin/semaphore-helper.h | 82 ------------- include/asm-blackfin/semaphore.h | 106 +---------------- include/asm-cris/semaphore-helper.h | 78 ------------- include/asm-cris/semaphore.h | 134 +-------------------- include/asm-frv/semaphore.h | 156 +------------------------ include/asm-h8300/semaphore-helper.h | 85 -------------- include/asm-h8300/semaphore.h | 191 +----------------------------- include/asm-ia64/semaphore.h | 100 +--------------- include/asm-m32r/semaphore.h | 145 +---------------------- include/asm-m68k/semaphore-helper.h | 142 ----------------------- include/asm-m68k/semaphore.h | 164 +------------------------- include/asm-m68knommu/semaphore-helper.h | 82 ------------- include/asm-m68knommu/semaphore.h | 154 +----------------------- include/asm-mips/semaphore.h | 109 +---------------- include/asm-mn10300/semaphore.h | 170 +-------------------------- include/asm-parisc/semaphore-helper.h | 89 -------------- include/asm-parisc/semaphore.h | 146 +---------------------- include/asm-powerpc/semaphore.h | 95 +-------------- include/asm-s390/semaphore.h | 108 +---------------- include/asm-sh/semaphore-helper.h | 89 -------------- include/asm-sh/semaphore.h | 116 +------------------ include/asm-sparc/semaphore.h | 193 +------------------------------ include/asm-sparc64/semaphore.h | 54 +-------- include/asm-um/semaphore.h | 7 +- include/asm-v850/semaphore.h | 85 +------------- include/asm-x86/semaphore.h | 6 +- include/asm-x86/semaphore_32.h | 175 ---------------------------- include/asm-x86/semaphore_64.h | 180 ---------------------------- include/asm-xtensa/semaphore.h | 100 +--------------- include/linux/semaphore.h | 77 ++++++++++++ 34 files changed, 100 insertions(+), 3760 deletions(-) delete mode 100644 include/asm-arm/semaphore-helper.h delete mode 100644 include/asm-blackfin/semaphore-helper.h delete mode 100644 include/asm-cris/semaphore-helper.h delete mode 100644 include/asm-h8300/semaphore-helper.h delete mode 100644 include/asm-m68k/semaphore-helper.h delete mode 100644 include/asm-m68knommu/semaphore-helper.h delete mode 100644 include/asm-parisc/semaphore-helper.h delete mode 100644 include/asm-sh/semaphore-helper.h delete mode 100644 include/asm-x86/semaphore_32.h delete mode 100644 include/asm-x86/semaphore_64.h create mode 100644 include/linux/semaphore.h (limited to 'include') diff --git a/include/asm-alpha/semaphore.h b/include/asm-alpha/semaphore.h index f1e9278a9fe2..d9b2034ed1d2 100644 --- a/include/asm-alpha/semaphore.h +++ b/include/asm-alpha/semaphore.h @@ -1,149 +1 @@ -#ifndef _ALPHA_SEMAPHORE_H -#define _ALPHA_SEMAPHORE_H - -/* - * SMP- and interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * (C) Copyright 1996, 2000 Richard Henderson - */ - -#include -#include -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait), \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - /* - * Logically, - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * except that gcc produces better initializing by parts yet. - */ - - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void down(struct semaphore *); -extern void __down_failed(struct semaphore *); -extern int down_interruptible(struct semaphore *); -extern int __down_failed_interruptible(struct semaphore *); -extern int down_trylock(struct semaphore *); -extern void up(struct semaphore *); -extern void __up_wakeup(struct semaphore *); - -/* - * Hidden out of line code is fun, but extremely messy. Rely on newer - * compilers to do a respectable job with this. The contention cases - * are handled out of line in arch/alpha/kernel/semaphore.c. - */ - -static inline void __down(struct semaphore *sem) -{ - long count; - might_sleep(); - count = atomic_dec_return(&sem->count); - if (unlikely(count < 0)) - __down_failed(sem); -} - -static inline int __down_interruptible(struct semaphore *sem) -{ - long count; - might_sleep(); - count = atomic_dec_return(&sem->count); - if (unlikely(count < 0)) - return __down_failed_interruptible(sem); - return 0; -} - -/* - * down_trylock returns 0 on success, 1 if we failed to get the lock. - */ - -static inline int __down_trylock(struct semaphore *sem) -{ - long ret; - - /* "Equivalent" C: - - do { - ret = ldl_l; - --ret; - if (ret < 0) - break; - ret = stl_c = ret; - } while (ret == 0); - */ - __asm__ __volatile__( - "1: ldl_l %0,%1\n" - " subl %0,1,%0\n" - " blt %0,2f\n" - " stl_c %0,%1\n" - " beq %0,3f\n" - " mb\n" - "2:\n" - ".subsection 2\n" - "3: br 1b\n" - ".previous" - : "=&r" (ret), "=m" (sem->count) - : "m" (sem->count)); - - return ret < 0; -} - -static inline void __up(struct semaphore *sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up_wakeup(sem); -} - -#if !defined(CONFIG_DEBUG_SEMAPHORE) -extern inline void down(struct semaphore *sem) -{ - __down(sem); -} -extern inline int down_interruptible(struct semaphore *sem) -{ - return __down_interruptible(sem); -} -extern inline int down_trylock(struct semaphore *sem) -{ - return __down_trylock(sem); -} -extern inline void up(struct semaphore *sem) -{ - __up(sem); -} -#endif - -#endif +#include diff --git a/include/asm-arm/semaphore-helper.h b/include/asm-arm/semaphore-helper.h deleted file mode 100644 index 1d7f1987edb9..000000000000 --- a/include/asm-arm/semaphore-helper.h +++ /dev/null @@ -1,84 +0,0 @@ -#ifndef ASMARM_SEMAPHORE_HELPER_H -#define ASMARM_SEMAPHORE_HELPER_H - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (atomic_read(&sem->count) <= 0) - sem->waking++; - spin_unlock_irqrestore(&semaphore_wake_lock, flags); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking > 0) { - sem->waking--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking non zero interruptible - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking > 0) { - sem->waking--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_try_lock: - * 1 failed to lock - * 0 got the lock - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - unsigned long flags; - int ret = 1; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking <= 0) - atomic_inc(&sem->count); - else { - sem->waking--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif diff --git a/include/asm-arm/semaphore.h b/include/asm-arm/semaphore.h index 1c8b441f89e3..d9b2034ed1d2 100644 --- a/include/asm-arm/semaphore.h +++ b/include/asm-arm/semaphore.h @@ -1,98 +1 @@ -/* - * linux/include/asm-arm/semaphore.h - */ -#ifndef __ASM_ARM_SEMAPHORE_H -#define __ASM_ARM_SEMAPHORE_H - -#include -#include -#include -#include - -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INIT(name, cnt) \ -{ \ - .count = ATOMIC_INIT(cnt), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait), \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INIT(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -/* - * special register calling convention - */ -asmlinkage void __down_failed(void); -asmlinkage int __down_interruptible_failed(void); -asmlinkage int __down_trylock_failed(void); -asmlinkage void __up_wakeup(void); - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern int __down_trylock(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -/* - * This is ugly, but we want the default case to fall through. - * "__down" is the actual routine that waits... - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - __down_op(sem, __down_failed); -} - -/* - * This is ugly, but we want the default case to fall through. - * "__down_interruptible" is the actual routine that waits... - */ -static inline int down_interruptible (struct semaphore * sem) -{ - might_sleep(); - return __down_op_ret(sem, __down_interruptible_failed); -} - -static inline int down_trylock(struct semaphore *sem) -{ - return __down_op_ret(sem, __down_trylock_failed); -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - __up_op(sem, __up_wakeup); -} - -#endif +#include diff --git a/include/asm-avr32/semaphore.h b/include/asm-avr32/semaphore.h index feaf1d453386..d9b2034ed1d2 100644 --- a/include/asm-avr32/semaphore.h +++ b/include/asm-avr32/semaphore.h @@ -1,108 +1 @@ -/* - * SMP- and interrupt-safe semaphores. - * - * Copyright (C) 2006 Atmel Corporation - * - * Based on include/asm-i386/semaphore.h - * Copyright (C) 1996 Linus Torvalds - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#ifndef __ASM_AVR32_SEMAPHORE_H -#define __ASM_AVR32_SEMAPHORE_H - -#include - -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -void __down(struct semaphore * sem); -int __down_interruptible(struct semaphore * sem); -void __up(struct semaphore * sem); - -/* - * This is ugly, but we want the default case to fall through. - * "__down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/i386/kernel/semaphore.c - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (unlikely(atomic_dec_return (&sem->count) < 0)) - __down (sem); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - if (unlikely(atomic_dec_return (&sem->count) < 0)) - ret = __down_interruptible (sem); - return ret; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - return atomic_dec_if_positive(&sem->count) < 0; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return (&sem->count) <= 0)) - __up (sem); -} - -#endif /*__ASM_AVR32_SEMAPHORE_H */ +#include diff --git a/include/asm-blackfin/semaphore-helper.h b/include/asm-blackfin/semaphore-helper.h deleted file mode 100644 index 9082b0dc3eb5..000000000000 --- a/include/asm-blackfin/semaphore-helper.h +++ /dev/null @@ -1,82 +0,0 @@ -/* Based on M68K version, Lineo Inc. May 2001 */ - -#ifndef _BFIN_SEMAPHORE_HELPER_H -#define _BFIN_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - */ - -#include - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore *sem) -{ - atomic_inc(&sem->waking); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret = 0; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret = 1; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 0; - } else - atomic_inc(&sem->count); - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif /* _BFIN_SEMAPHORE_HELPER_H */ diff --git a/include/asm-blackfin/semaphore.h b/include/asm-blackfin/semaphore.h index 533f90fb2e4e..d9b2034ed1d2 100644 --- a/include/asm-blackfin/semaphore.h +++ b/include/asm-blackfin/semaphore.h @@ -1,105 +1 @@ -#ifndef _BFIN_SEMAPHORE_H -#define _BFIN_SEMAPHORE_H - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include -#include - -/* - * Interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * BFIN version by akbar hussain Lineo Inc April 2001 - * - */ - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down(struct semaphore *sem); -asmlinkage int __down_interruptible(struct semaphore *sem); -asmlinkage int __down_trylock(struct semaphore *sem); -asmlinkage void __up(struct semaphore *sem); - -extern spinlock_t semaphore_wake_lock; - -/* - * This is ugly, but we want the default case to fall through. - * "down_failed" is a special asm handler that calls the C - * routine that actually waits. - */ -static inline void down(struct semaphore *sem) -{ - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - __down(sem); -} - -static inline int down_interruptible(struct semaphore *sem) -{ - int ret = 0; - - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - ret = __down_interruptible(sem); - return (ret); -} - -static inline int down_trylock(struct semaphore *sem) -{ - int ret = 0; - - if (atomic_dec_return(&sem->count) < 0) - ret = __down_trylock(sem); - return ret; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore *sem) -{ - if (atomic_inc_return(&sem->count) <= 0) - __up(sem); -} - -#endif /* __ASSEMBLY__ */ -#endif /* _BFIN_SEMAPHORE_H */ +#include diff --git a/include/asm-cris/semaphore-helper.h b/include/asm-cris/semaphore-helper.h deleted file mode 100644 index 27bfeca1b981..000000000000 --- a/include/asm-cris/semaphore-helper.h +++ /dev/null @@ -1,78 +0,0 @@ -/* $Id: semaphore-helper.h,v 1.3 2001/03/26 15:00:33 orjanf Exp $ - * - * SMP- and interrupt-safe semaphores helper functions. Generic versions, no - * optimizations whatsoever... - * - */ - -#ifndef _ASM_SEMAPHORE_HELPER_H -#define _ASM_SEMAPHORE_HELPER_H - -#include -#include - -#define read(a) ((a)->counter) -#define inc(a) (((a)->counter)++) -#define dec(a) (((a)->counter)--) - -#define count_inc(a) ((*(a))++) - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - atomic_inc(&sem->waking); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - local_irq_save(flags); - if (read(&sem->waking) > 0) { - dec(&sem->waking); - ret = 1; - } - local_irq_restore(flags); - return ret; -} - -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret = 0; - unsigned long flags; - - local_irq_save(flags); - if (read(&sem->waking) > 0) { - dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - inc(&sem->count); - ret = -EINTR; - } - local_irq_restore(flags); - return ret; -} - -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret = 1; - unsigned long flags; - - local_irq_save(flags); - if (read(&sem->waking) <= 0) - inc(&sem->count); - else { - dec(&sem->waking); - ret = 0; - } - local_irq_restore(flags); - return ret; -} - -#endif /* _ASM_SEMAPHORE_HELPER_H */ - - diff --git a/include/asm-cris/semaphore.h b/include/asm-cris/semaphore.h index 31a4ac448195..d9b2034ed1d2 100644 --- a/include/asm-cris/semaphore.h +++ b/include/asm-cris/semaphore.h @@ -1,133 +1 @@ -/* $Id: semaphore.h,v 1.3 2001/05/08 13:54:09 bjornw Exp $ */ - -/* On the i386 these are coded in asm, perhaps we should as well. Later.. */ - -#ifndef _CRIS_SEMAPHORE_H -#define _CRIS_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#include -#include -#include - -#include -#include - -/* - * CRIS semaphores, implemented in C-only so far. - */ - -struct semaphore { - atomic_t count; - atomic_t waking; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .waking = ATOMIC_INIT(0), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern int __down_trylock(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -/* notice - we probably can do cli/sti here instead of saving */ - -static inline void down(struct semaphore * sem) -{ - unsigned long flags; - int failed; - - might_sleep(); - - /* atomically decrement the semaphores count, and if its negative, we wait */ - cris_atomic_save(sem, flags); - failed = --(sem->count.counter) < 0; - cris_atomic_restore(sem, flags); - if(failed) { - __down(sem); - } -} - -/* - * This version waits in interruptible state so that the waiting - * process can be killed. The down_interruptible routine - * returns negative for signalled and zero for semaphore acquired. - */ - -static inline int down_interruptible(struct semaphore * sem) -{ - unsigned long flags; - int failed; - - might_sleep(); - - /* atomically decrement the semaphores count, and if its negative, we wait */ - cris_atomic_save(sem, flags); - failed = --(sem->count.counter) < 0; - cris_atomic_restore(sem, flags); - if(failed) - failed = __down_interruptible(sem); - return(failed); -} - -static inline int down_trylock(struct semaphore * sem) -{ - unsigned long flags; - int failed; - - cris_atomic_save(sem, flags); - failed = --(sem->count.counter) < 0; - cris_atomic_restore(sem, flags); - if(failed) - failed = __down_trylock(sem); - return(failed); - -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - unsigned long flags; - int wakeup; - - /* atomically increment the semaphores count, and if it was negative, we wake people */ - cris_atomic_save(sem, flags); - wakeup = ++(sem->count.counter) <= 0; - cris_atomic_restore(sem, flags); - if(wakeup) { - __up(sem); - } -} - -#endif +#include diff --git a/include/asm-frv/semaphore.h b/include/asm-frv/semaphore.h index d7aaa1911a1a..d9b2034ed1d2 100644 --- a/include/asm-frv/semaphore.h +++ b/include/asm-frv/semaphore.h @@ -1,155 +1 @@ -/* semaphore.h: semaphores for the FR-V - * - * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ -#ifndef _ASM_SEMAPHORE_H -#define _ASM_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include - -/* - * the semaphore definition - * - if counter is >0 then there are tokens available on the semaphore for down to collect - * - if counter is <=0 then there are no spare tokens, and anyone that wants one must wait - * - if wait_list is not empty, then there are processes waiting for the semaphore - */ -struct semaphore { - unsigned counter; - spinlock_t wait_lock; - struct list_head wait_list; -#ifdef CONFIG_DEBUG_SEMAPHORE - unsigned __magic; -#endif -}; - -#ifdef CONFIG_DEBUG_SEMAPHORE -# define __SEM_DEBUG_INIT(name) , (long)&(name).__magic -#else -# define __SEM_DEBUG_INIT(name) -#endif - - -#define __SEMAPHORE_INITIALIZER(name,count) \ -{ count, SPIN_LOCK_UNLOCKED, LIST_HEAD_INIT((name).wait_list) __SEM_DEBUG_INIT(name) } - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore *sem, unsigned long flags); -extern int __down_interruptible(struct semaphore *sem, unsigned long flags); -extern void __up(struct semaphore *sem); - -static inline void down(struct semaphore *sem) -{ - unsigned long flags; - -#ifdef CONFIG_DEBUG_SEMAPHORE - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (likely(sem->counter > 0)) { - sem->counter--; - spin_unlock_irqrestore(&sem->wait_lock, flags); - } - else { - __down(sem, flags); - } -} - -static inline int down_interruptible(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - -#ifdef CONFIG_DEBUG_SEMAPHORE - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (likely(sem->counter > 0)) { - sem->counter--; - spin_unlock_irqrestore(&sem->wait_lock, flags); - } - else { - ret = __down_interruptible(sem, flags); - } - return ret; -} - -/* - * non-blockingly attempt to down() a semaphore. - * - returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore *sem) -{ - unsigned long flags; - int success = 0; - -#ifdef CONFIG_DEBUG_SEMAPHORE - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (sem->counter > 0) { - sem->counter--; - success = 1; - } - spin_unlock_irqrestore(&sem->wait_lock, flags); - return !success; -} - -static inline void up(struct semaphore *sem) -{ - unsigned long flags; - -#ifdef CONFIG_DEBUG_SEMAPHORE - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (!list_empty(&sem->wait_list)) - __up(sem); - else - sem->counter++; - spin_unlock_irqrestore(&sem->wait_lock, flags); -} - -static inline int sem_getcount(struct semaphore *sem) -{ - return sem->counter; -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-h8300/semaphore-helper.h b/include/asm-h8300/semaphore-helper.h deleted file mode 100644 index 4fea36be5fd8..000000000000 --- a/include/asm-h8300/semaphore-helper.h +++ /dev/null @@ -1,85 +0,0 @@ -#ifndef _H8300_SEMAPHORE_HELPER_H -#define _H8300_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - * based on - * m68k version by Andreas Schwab - */ - -#include - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - atomic_inc((atomic_t *)&sem->sleepers); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 1; - if (sem->sleepers <= 0) - atomic_inc(&sem->count); - else { - sem->sleepers--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif diff --git a/include/asm-h8300/semaphore.h b/include/asm-h8300/semaphore.h index f3ffff83ff09..d9b2034ed1d2 100644 --- a/include/asm-h8300/semaphore.h +++ b/include/asm-h8300/semaphore.h @@ -1,190 +1 @@ -#ifndef _H8300_SEMAPHORE_H -#define _H8300_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include - -#include -#include - -/* - * Interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * H8/300 version by Yoshinori Sato - */ - - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -extern spinlock_t semaphore_wake_lock; - -/* - * This is ugly, but we want the default case to fall through. - * "down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/m68k/lib/semaphore.S - */ -static inline void down(struct semaphore * sem) -{ - register atomic_t *count asm("er0"); - - might_sleep(); - - count = &(sem->count); - __asm__ __volatile__( - "stc ccr,r3l\n\t" - "orc #0x80,ccr\n\t" - "mov.l %2, er1\n\t" - "dec.l #1,er1\n\t" - "mov.l er1,%0\n\t" - "bpl 1f\n\t" - "ldc r3l,ccr\n\t" - "mov.l %1,er0\n\t" - "jsr @___down\n\t" - "bra 2f\n" - "1:\n\t" - "ldc r3l,ccr\n" - "2:" - : "=m"(*count) - : "g"(sem),"m"(*count) - : "cc", "er1", "er2", "er3"); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - register atomic_t *count asm("er0"); - - might_sleep(); - - count = &(sem->count); - __asm__ __volatile__( - "stc ccr,r1l\n\t" - "orc #0x80,ccr\n\t" - "mov.l %3, er2\n\t" - "dec.l #1,er2\n\t" - "mov.l er2,%1\n\t" - "bpl 1f\n\t" - "ldc r1l,ccr\n\t" - "mov.l %2,er0\n\t" - "jsr @___down_interruptible\n\t" - "bra 2f\n" - "1:\n\t" - "ldc r1l,ccr\n\t" - "sub.l %0,%0\n\t" - "2:\n\t" - : "=r" (count),"=m" (*count) - : "g"(sem),"m"(*count) - : "cc", "er1", "er2", "er3"); - return (int)count; -} - -static inline int down_trylock(struct semaphore * sem) -{ - register atomic_t *count asm("er0"); - - count = &(sem->count); - __asm__ __volatile__( - "stc ccr,r3l\n\t" - "orc #0x80,ccr\n\t" - "mov.l %3,er2\n\t" - "dec.l #1,er2\n\t" - "mov.l er2,%0\n\t" - "bpl 1f\n\t" - "ldc r3l,ccr\n\t" - "jmp @3f\n\t" - LOCK_SECTION_START(".align 2\n\t") - "3:\n\t" - "mov.l %2,er0\n\t" - "jsr @___down_trylock\n\t" - "jmp @2f\n\t" - LOCK_SECTION_END - "1:\n\t" - "ldc r3l,ccr\n\t" - "sub.l %1,%1\n" - "2:" - : "=m" (*count),"=r"(count) - : "g"(sem),"m"(*count) - : "cc", "er1","er2", "er3"); - return (int)count; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - register atomic_t *count asm("er0"); - - count = &(sem->count); - __asm__ __volatile__( - "stc ccr,r3l\n\t" - "orc #0x80,ccr\n\t" - "mov.l %2,er1\n\t" - "inc.l #1,er1\n\t" - "mov.l er1,%0\n\t" - "ldc r3l,ccr\n\t" - "sub.l er2,er2\n\t" - "cmp.l er2,er1\n\t" - "bgt 1f\n\t" - "mov.l %1,er0\n\t" - "jsr @___up\n" - "1:" - : "=m"(*count) - : "g"(sem),"m"(*count) - : "cc", "er1", "er2", "er3"); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-ia64/semaphore.h b/include/asm-ia64/semaphore.h index d8393d11288d..d9b2034ed1d2 100644 --- a/include/asm-ia64/semaphore.h +++ b/include/asm-ia64/semaphore.h @@ -1,99 +1 @@ -#ifndef _ASM_IA64_SEMAPHORE_H -#define _ASM_IA64_SEMAPHORE_H - -/* - * Copyright (C) 1998-2000 Hewlett-Packard Co - * Copyright (C) 1998-2000 David Mosberger-Tang - */ - -#include -#include - -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) - -static inline void -sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void -init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void -init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down (struct semaphore * sem); -extern int __down_interruptible (struct semaphore * sem); -extern int __down_trylock (struct semaphore * sem); -extern void __up (struct semaphore * sem); - -/* - * Atomically decrement the semaphore's count. If it goes negative, - * block the calling thread in the TASK_UNINTERRUPTIBLE state. - */ -static inline void -down (struct semaphore *sem) -{ - might_sleep(); - if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) - __down(sem); -} - -/* - * Atomically decrement the semaphore's count. If it goes negative, - * block the calling thread in the TASK_INTERRUPTIBLE state. - */ -static inline int -down_interruptible (struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) - ret = __down_interruptible(sem); - return ret; -} - -static inline int -down_trylock (struct semaphore *sem) -{ - int ret = 0; - - if (ia64_fetchadd(-1, &sem->count.counter, acq) < 1) - ret = __down_trylock(sem); - return ret; -} - -static inline void -up (struct semaphore * sem) -{ - if (ia64_fetchadd(1, &sem->count.counter, rel) <= -1) - __up(sem); -} - -#endif /* _ASM_IA64_SEMAPHORE_H */ +#include diff --git a/include/asm-m32r/semaphore.h b/include/asm-m32r/semaphore.h index b5bf95a6f2b4..d9b2034ed1d2 100644 --- a/include/asm-m32r/semaphore.h +++ b/include/asm-m32r/semaphore.h @@ -1,144 +1 @@ -#ifndef _ASM_M32R_SEMAPHORE_H -#define _ASM_M32R_SEMAPHORE_H - -#include - -#ifdef __KERNEL__ - -/* - * SMP- and interrupt-safe semaphores.. - * - * Copyright (C) 1996 Linus Torvalds - * Copyright (C) 2004, 2006 Hirokazu Takata - */ - -#include -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesnt. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* - * Atomically decrement the semaphore's count. If it goes negative, - * block the calling thread in the TASK_UNINTERRUPTIBLE state. - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (unlikely(atomic_dec_return(&sem->count) < 0)) - __down(sem); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int result = 0; - - might_sleep(); - if (unlikely(atomic_dec_return(&sem->count) < 0)) - result = __down_interruptible(sem); - - return result; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - unsigned long flags; - long count; - int result = 0; - - local_irq_save(flags); - __asm__ __volatile__ ( - "# down_trylock \n\t" - DCACHE_CLEAR("%0", "r4", "%1") - M32R_LOCK" %0, @%1; \n\t" - "addi %0, #-1; \n\t" - M32R_UNLOCK" %0, @%1; \n\t" - : "=&r" (count) - : "r" (&sem->count) - : "memory" -#ifdef CONFIG_CHIP_M32700_TS1 - , "r4" -#endif /* CONFIG_CHIP_M32700_TS1 */ - ); - local_irq_restore(flags); - - if (unlikely(count < 0)) - result = __down_trylock(sem); - - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up(sem); -} - -#endif /* __KERNEL__ */ - -#endif /* _ASM_M32R_SEMAPHORE_H */ +#include diff --git a/include/asm-m68k/semaphore-helper.h b/include/asm-m68k/semaphore-helper.h deleted file mode 100644 index eef30ba0b499..000000000000 --- a/include/asm-m68k/semaphore-helper.h +++ /dev/null @@ -1,142 +0,0 @@ -#ifndef _M68K_SEMAPHORE_HELPER_H -#define _M68K_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - -#include - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - atomic_inc(&sem->waking); -} - -#ifndef CONFIG_RMW_INSNS -extern spinlock_t semaphore_wake_lock; -#endif - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; -#ifndef CONFIG_RMW_INSNS - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); -#else - int tmp1, tmp2; - - __asm__ __volatile__ - ("1: movel %1,%2\n" - " jle 2f\n" - " subql #1,%2\n" - " casl %1,%2,%3\n" - " jne 1b\n" - " moveq #1,%0\n" - "2:" - : "=d" (ret), "=d" (tmp1), "=d" (tmp2) - : "m" (sem->waking), "0" (0), "1" (sem->waking)); -#endif - - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret; -#ifndef CONFIG_RMW_INSNS - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); -#else - int tmp1, tmp2; - - __asm__ __volatile__ - ("1: movel %1,%2\n" - " jle 2f\n" - " subql #1,%2\n" - " casl %1,%2,%3\n" - " jne 1b\n" - " moveq #1,%0\n" - " jra %a4\n" - "2:" - : "=d" (ret), "=d" (tmp1), "=d" (tmp2) - : "m" (sem->waking), "i" (&&next), "0" (0), "1" (sem->waking)); - if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } -next: -#endif - - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret; -#ifndef CONFIG_RMW_INSNS - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 1; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 0; - } else - atomic_inc(&sem->count); - spin_unlock_irqrestore(&semaphore_wake_lock, flags); -#else - int tmp1, tmp2; - - __asm__ __volatile__ - ("1: movel %1,%2\n" - " jle 2f\n" - " subql #1,%2\n" - " casl %1,%2,%3\n" - " jne 1b\n" - " moveq #0,%0\n" - "2:" - : "=d" (ret), "=d" (tmp1), "=d" (tmp2) - : "m" (sem->waking), "0" (1), "1" (sem->waking)); - if (ret) - atomic_inc(&sem->count); -#endif - return ret; -} - -#endif diff --git a/include/asm-m68k/semaphore.h b/include/asm-m68k/semaphore.h index 64d6b119bb0a..d9b2034ed1d2 100644 --- a/include/asm-m68k/semaphore.h +++ b/include/asm-m68k/semaphore.h @@ -1,163 +1 @@ -#ifndef _M68K_SEMAPHORE_H -#define _M68K_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include -#include - -#include -#include - -/* - * Interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - - -struct semaphore { - atomic_t count; - atomic_t waking; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .waking = ATOMIC_INIT(0), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* - * This is ugly, but we want the default case to fall through. - * "down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/m68k/lib/semaphore.S - */ -static inline void down(struct semaphore *sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - - might_sleep(); - __asm__ __volatile__( - "| atomic down operation\n\t" - "subql #1,%0@\n\t" - "jmi 2f\n\t" - "1:\n" - LOCK_SECTION_START(".even\n\t") - "2:\tpea 1b\n\t" - "jbra __down_failed\n" - LOCK_SECTION_END - : /* no outputs */ - : "a" (sem1) - : "memory"); -} - -static inline int down_interruptible(struct semaphore *sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - register int result __asm__ ("%d0"); - - might_sleep(); - __asm__ __volatile__( - "| atomic interruptible down operation\n\t" - "subql #1,%1@\n\t" - "jmi 2f\n\t" - "clrl %0\n" - "1:\n" - LOCK_SECTION_START(".even\n\t") - "2:\tpea 1b\n\t" - "jbra __down_failed_interruptible\n" - LOCK_SECTION_END - : "=d" (result) - : "a" (sem1) - : "memory"); - return result; -} - -static inline int down_trylock(struct semaphore *sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - register int result __asm__ ("%d0"); - - __asm__ __volatile__( - "| atomic down trylock operation\n\t" - "subql #1,%1@\n\t" - "jmi 2f\n\t" - "clrl %0\n" - "1:\n" - LOCK_SECTION_START(".even\n\t") - "2:\tpea 1b\n\t" - "jbra __down_failed_trylock\n" - LOCK_SECTION_END - : "=d" (result) - : "a" (sem1) - : "memory"); - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore *sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - - __asm__ __volatile__( - "| atomic up operation\n\t" - "addql #1,%0@\n\t" - "jle 2f\n" - "1:\n" - LOCK_SECTION_START(".even\n\t") - "2:\t" - "pea 1b\n\t" - "jbra __up_wakeup\n" - LOCK_SECTION_END - : /* no outputs */ - : "a" (sem1) - : "memory"); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-m68knommu/semaphore-helper.h b/include/asm-m68knommu/semaphore-helper.h deleted file mode 100644 index 43da7bc483c7..000000000000 --- a/include/asm-m68knommu/semaphore-helper.h +++ /dev/null @@ -1,82 +0,0 @@ -#ifndef _M68K_SEMAPHORE_HELPER_H -#define _M68K_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore * sem) -{ - atomic_inc(&sem->waking); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret; - unsigned long flags; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 1; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 0; - } else - atomic_inc(&sem->count); - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif diff --git a/include/asm-m68knommu/semaphore.h b/include/asm-m68knommu/semaphore.h index 5779eb6c0689..d9b2034ed1d2 100644 --- a/include/asm-m68knommu/semaphore.h +++ b/include/asm-m68knommu/semaphore.h @@ -1,153 +1 @@ -#ifndef _M68K_SEMAPHORE_H -#define _M68K_SEMAPHORE_H - -#define RW_LOCK_BIAS 0x01000000 - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include - -#include -#include - -/* - * Interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * m68k version by Andreas Schwab - */ - - -struct semaphore { - atomic_t count; - atomic_t waking; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .waking = ATOMIC_INIT(0), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -extern spinlock_t semaphore_wake_lock; - -/* - * This is ugly, but we want the default case to fall through. - * "down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/m68k/lib/semaphore.S - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - __asm__ __volatile__( - "| atomic down operation\n\t" - "movel %0, %%a1\n\t" - "lea %%pc@(1f), %%a0\n\t" - "subql #1, %%a1@\n\t" - "jmi __down_failed\n" - "1:" - : /* no outputs */ - : "g" (sem) - : "cc", "%a0", "%a1", "memory"); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret; - - might_sleep(); - __asm__ __volatile__( - "| atomic down operation\n\t" - "movel %1, %%a1\n\t" - "lea %%pc@(1f), %%a0\n\t" - "subql #1, %%a1@\n\t" - "jmi __down_failed_interruptible\n\t" - "clrl %%d0\n" - "1: movel %%d0, %0\n" - : "=d" (ret) - : "g" (sem) - : "cc", "%d0", "%a0", "%a1", "memory"); - return(ret); -} - -static inline int down_trylock(struct semaphore * sem) -{ - register struct semaphore *sem1 __asm__ ("%a1") = sem; - register int result __asm__ ("%d0"); - - __asm__ __volatile__( - "| atomic down trylock operation\n\t" - "subql #1,%1@\n\t" - "jmi 2f\n\t" - "clrl %0\n" - "1:\n" - ".section .text.lock,\"ax\"\n" - ".even\n" - "2:\tpea 1b\n\t" - "jbra __down_failed_trylock\n" - ".previous" - : "=d" (result) - : "a" (sem1) - : "memory"); - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - __asm__ __volatile__( - "| atomic up operation\n\t" - "movel %0, %%a1\n\t" - "lea %%pc@(1f), %%a0\n\t" - "addql #1, %%a1@\n\t" - "jle __up_wakeup\n" - "1:" - : /* no outputs */ - : "g" (sem) - : "cc", "%a0", "%a1", "memory"); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-mips/semaphore.h b/include/asm-mips/semaphore.h index fdf8042b784b..d9b2034ed1d2 100644 --- a/include/asm-mips/semaphore.h +++ b/include/asm-mips/semaphore.h @@ -1,108 +1 @@ -/* - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * Copyright (C) 1996 Linus Torvalds - * Copyright (C) 1998, 99, 2000, 01, 04 Ralf Baechle - * Copyright (C) 1999, 2000, 01 Silicon Graphics, Inc. - * Copyright (C) 2000, 01 MIPS Technologies, Inc. - * - * In all honesty, little of the old MIPS code left - the PPC64 variant was - * just looking nice and portable so I ripped it. Credits to whoever wrote - * it. - */ -#ifndef __ASM_SEMAPHORE_H -#define __ASM_SEMAPHORE_H - -/* - * Remove spinlock-based RW semaphores; RW semaphore definitions are - * now in rwsem.h and we use the generic lib/rwsem.c implementation. - * Rework semaphores to use atomic_dec_if_positive. - * -- Paul Mackerras (paulus@samba.org) - */ - -#ifdef __KERNEL__ - -#include -#include -#include -#include - -struct semaphore { - /* - * Note that any negative value of count is equivalent to 0, - * but additionally indicates that some process(es) might be - * sleeping on `wait'. - */ - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name, count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) - -static inline void sema_init(struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - - /* - * Try to get the semaphore, take the slow path if we fail. - */ - if (unlikely(atomic_dec_return(&sem->count) < 0)) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - - if (unlikely(atomic_dec_return(&sem->count) < 0)) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - return atomic_dec_if_positive(&sem->count) < 0; -} - -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up(sem); -} - -#endif /* __KERNEL__ */ - -#endif /* __ASM_SEMAPHORE_H */ +#include diff --git a/include/asm-mn10300/semaphore.h b/include/asm-mn10300/semaphore.h index 5a9e1ad0b253..d9b2034ed1d2 100644 --- a/include/asm-mn10300/semaphore.h +++ b/include/asm-mn10300/semaphore.h @@ -1,169 +1 @@ -/* MN10300 Semaphores - * - * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public Licence - * as published by the Free Software Foundation; either version - * 2 of the Licence, or (at your option) any later version. - */ -#ifndef _ASM_SEMAPHORE_H -#define _ASM_SEMAPHORE_H - -#ifndef __ASSEMBLY__ - -#include -#include -#include -#include - -#define SEMAPHORE_DEBUG 0 - -/* - * the semaphore definition - * - if count is >0 then there are tokens available on the semaphore for down - * to collect - * - if count is <=0 then there are no spare tokens, and anyone that wants one - * must wait - * - if wait_list is not empty, then there are processes waiting for the - * semaphore - */ -struct semaphore { - atomic_t count; /* it's not really atomic, it's - * just that certain modules - * expect to be able to access - * it directly */ - spinlock_t wait_lock; - struct list_head wait_list; -#if SEMAPHORE_DEBUG - unsigned __magic; -#endif -}; - -#if SEMAPHORE_DEBUG -# define __SEM_DEBUG_INIT(name) , (long)&(name).__magic -#else -# define __SEM_DEBUG_INIT(name) -#endif - - -#define __SEMAPHORE_INITIALIZER(name, init_count) \ -{ \ - .count = ATOMIC_INIT(init_count), \ - .wait_lock = __SPIN_LOCK_UNLOCKED((name).wait_lock), \ - .wait_list = LIST_HEAD_INIT((name).wait_list) \ - __SEM_DEBUG_INIT(name) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) -#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name, 0) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore *sem, unsigned long flags); -extern int __down_interruptible(struct semaphore *sem, unsigned long flags); -extern void __up(struct semaphore *sem); - -static inline void down(struct semaphore *sem) -{ - unsigned long flags; - int count; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); - } else { - __down(sem, flags); - } -} - -static inline int down_interruptible(struct semaphore *sem) -{ - unsigned long flags; - int count, ret = 0; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); - } else { - ret = __down_interruptible(sem, flags); - } - return ret; -} - -/* - * non-blockingly attempt to down() a semaphore. - * - returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore *sem) -{ - unsigned long flags; - int count, success = 0; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - success = 1; - } - spin_unlock_irqrestore(&sem->wait_lock, flags); - return !success; -} - -static inline void up(struct semaphore *sem) -{ - unsigned long flags; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (!list_empty(&sem->wait_list)) - __up(sem); - else - atomic_set(&sem->count, atomic_read(&sem->count) + 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); -} - -static inline int sem_getcount(struct semaphore *sem) -{ - return atomic_read(&sem->count); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include diff --git a/include/asm-parisc/semaphore-helper.h b/include/asm-parisc/semaphore-helper.h deleted file mode 100644 index 387f7c1277a2..000000000000 --- a/include/asm-parisc/semaphore-helper.h +++ /dev/null @@ -1,89 +0,0 @@ -#ifndef _ASM_PARISC_SEMAPHORE_HELPER_H -#define _ASM_PARISC_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * (C) Copyright 1999 Andrea Arcangeli - */ - -/* - * These two _must_ execute atomically wrt each other. - * - * This is trivially done with load_locked/store_cond, - * which we have. Let the rest of the losers suck eggs. - */ -static __inline__ void wake_one_more(struct semaphore * sem) -{ - atomic_inc((atomic_t *)&sem->waking); -} - -static __inline__ int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking > 0) { - sem->waking--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static __inline__ int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking > 0) { - sem->waking--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - * - * We must undo the sem->count down_trylock() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static __inline__ int waking_non_zero_trylock(struct semaphore *sem) -{ - unsigned long flags; - int ret = 1; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->waking <= 0) - atomic_inc(&sem->count); - else { - sem->waking--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif /* _ASM_PARISC_SEMAPHORE_HELPER_H */ diff --git a/include/asm-parisc/semaphore.h b/include/asm-parisc/semaphore.h index a16271cdc748..d9b2034ed1d2 100644 --- a/include/asm-parisc/semaphore.h +++ b/include/asm-parisc/semaphore.h @@ -1,145 +1 @@ -/* SMP- and interrupt-safe semaphores. - * PA-RISC version by Matthew Wilcox - * - * Linux/PA-RISC Project (http://www.parisc-linux.org/) - * Copyright (C) 1996 Linus Torvalds - * Copyright (C) 1999-2001 Matthew Wilcox < willy at debian d0T org > - * Copyright (C) 2000 Grant Grundler < grundler a debian org > - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ - -#ifndef _ASM_PARISC_SEMAPHORE_H -#define _ASM_PARISC_SEMAPHORE_H - -#include -#include -#include - -#include - -/* - * The `count' is initialised to the number of people who are allowed to - * take the lock. (Normally we want a mutex, so this is `1'). if - * `count' is positive, the lock can be taken. if it's 0, no-one is - * waiting on it. if it's -1, at least one task is waiting. - */ -struct semaphore { - spinlock_t sentry; - int count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .sentry = SPIN_LOCK_UNLOCKED, \ - .count = n, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -static inline int sem_getcount(struct semaphore *sem) -{ - return sem->count; -} - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* Semaphores can be `tried' from irq context. So we have to disable - * interrupts while we're messing with the semaphore. Sorry. - */ - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - spin_lock_irq(&sem->sentry); - if (sem->count > 0) { - sem->count--; - } else { - __down(sem); - } - spin_unlock_irq(&sem->sentry); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - might_sleep(); - spin_lock_irq(&sem->sentry); - if (sem->count > 0) { - sem->count--; - } else { - ret = __down_interruptible(sem); - } - spin_unlock_irq(&sem->sentry); - return ret; -} - -/* - * down_trylock returns 0 on success, 1 if we failed to get the lock. - * May not sleep, but must preserve irq state - */ -static inline int down_trylock(struct semaphore * sem) -{ - unsigned long flags; - int count; - - spin_lock_irqsave(&sem->sentry, flags); - count = sem->count - 1; - if (count >= 0) - sem->count = count; - spin_unlock_irqrestore(&sem->sentry, flags); - return (count < 0); -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - */ -static inline void up(struct semaphore * sem) -{ - unsigned long flags; - - spin_lock_irqsave(&sem->sentry, flags); - if (sem->count < 0) { - __up(sem); - } else { - sem->count++; - } - spin_unlock_irqrestore(&sem->sentry, flags); -} - -#endif /* _ASM_PARISC_SEMAPHORE_H */ +#include diff --git a/include/asm-powerpc/semaphore.h b/include/asm-powerpc/semaphore.h index 48dd32e07749..d9b2034ed1d2 100644 --- a/include/asm-powerpc/semaphore.h +++ b/include/asm-powerpc/semaphore.h @@ -1,94 +1 @@ -#ifndef _ASM_POWERPC_SEMAPHORE_H -#define _ASM_POWERPC_SEMAPHORE_H - -/* - * Remove spinlock-based RW semaphores; RW semaphore definitions are - * now in rwsem.h and we use the generic lib/rwsem.c implementation. - * Rework semaphores to use atomic_dec_if_positive. - * -- Paul Mackerras (paulus@samba.org) - */ - -#ifdef __KERNEL__ - -#include -#include -#include -#include - -struct semaphore { - /* - * Note that any negative value of count is equivalent to 0, - * but additionally indicates that some process(es) might be - * sleeping on `wait'. - */ - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name, count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - - /* - * Try to get the semaphore, take the slow path if we fail. - */ - if (unlikely(atomic_dec_return(&sem->count) < 0)) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - - if (unlikely(atomic_dec_return(&sem->count) < 0)) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - return atomic_dec_if_positive(&sem->count) < 0; -} - -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up(sem); -} - -#endif /* __KERNEL__ */ - -#endif /* _ASM_POWERPC_SEMAPHORE_H */ +#include diff --git a/include/asm-s390/semaphore.h b/include/asm-s390/semaphore.h index 0e7001ad8392..d9b2034ed1d2 100644 --- a/include/asm-s390/semaphore.h +++ b/include/asm-s390/semaphore.h @@ -1,107 +1 @@ -/* - * include/asm-s390/semaphore.h - * - * S390 version - * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation - * - * Derived from "include/asm-i386/semaphore.h" - * (C) Copyright 1996 Linus Torvalds - */ - -#ifndef _S390_SEMAPHORE_H -#define _S390_SEMAPHORE_H - -#include -#include -#include -#include - -struct semaphore { - /* - * Note that any negative value of count is equivalent to 0, - * but additionally indicates that some process(es) might be - * sleeping on `wait'. - */ - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name,count) \ - { ATOMIC_INIT(count), __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) } - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - int old_val, new_val; - - /* - * This inline assembly atomically implements the equivalent - * to the following C code: - * old_val = sem->count.counter; - * if ((new_val = old_val) > 0) - * sem->count.counter = --new_val; - * In the ppc code this is called atomic_dec_if_positive. - */ - asm volatile( - " l %0,0(%3)\n" - "0: ltr %1,%0\n" - " jle 1f\n" - " ahi %1,-1\n" - " cs %0,%1,0(%3)\n" - " jl 0b\n" - "1:" - : "=&d" (old_val), "=&d" (new_val), "=m" (sem->count.counter) - : "a" (&sem->count.counter), "m" (sem->count.counter) - : "cc", "memory"); - return old_val <= 0; -} - -static inline void up(struct semaphore * sem) -{ - if (atomic_inc_return(&sem->count) <= 0) - __up(sem); -} - -#endif +#include diff --git a/include/asm-sh/semaphore-helper.h b/include/asm-sh/semaphore-helper.h deleted file mode 100644 index bd8230c369ca..000000000000 --- a/include/asm-sh/semaphore-helper.h +++ /dev/null @@ -1,89 +0,0 @@ -#ifndef __ASM_SH_SEMAPHORE_HELPER_H -#define __ASM_SH_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * (C) Copyright 1999 Andrea Arcangeli - */ - -/* - * These two _must_ execute atomically wrt each other. - * - * This is trivially done with load_locked/store_cond, - * which we have. Let the rest of the losers suck eggs. - */ -static __inline__ void wake_one_more(struct semaphore * sem) -{ - atomic_inc((atomic_t *)&sem->sleepers); -} - -static __inline__ int waking_non_zero(struct semaphore *sem) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - * - * We must undo the sem->count down_interruptible() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static __inline__ int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers > 0) { - sem->sleepers--; - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - * - * We must undo the sem->count down_trylock() increment while we are - * protected by the spinlock in order to make atomic this atomic_inc() with the - * atomic_read() in wake_one_more(), otherwise we can race. -arca - */ -static __inline__ int waking_non_zero_trylock(struct semaphore *sem) -{ - unsigned long flags; - int ret = 1; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (sem->sleepers <= 0) - atomic_inc(&sem->count); - else { - sem->sleepers--; - ret = 0; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif /* __ASM_SH_SEMAPHORE_HELPER_H */ diff --git a/include/asm-sh/semaphore.h b/include/asm-sh/semaphore.h index 9e5a37c4dce2..d9b2034ed1d2 100644 --- a/include/asm-sh/semaphore.h +++ b/include/asm-sh/semaphore.h @@ -1,115 +1 @@ -#ifndef __ASM_SH_SEMAPHORE_H -#define __ASM_SH_SEMAPHORE_H - -#include - -#ifdef __KERNEL__ -/* - * SMP- and interrupt-safe semaphores. - * - * (C) Copyright 1996 Linus Torvalds - * - * SuperH verison by Niibe Yutaka - * (Currently no asm implementation but generic C code...) - */ - -#include -#include -#include - -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesn't. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -#if 0 -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); -#endif - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -extern spinlock_t semaphore_wake_lock; - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - if (atomic_dec_return(&sem->count) < 0) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - int ret = 0; - - if (atomic_dec_return(&sem->count) < 0) - ret = __down_trylock(sem); - return ret; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - */ -static inline void up(struct semaphore * sem) -{ - if (atomic_inc_return(&sem->count) <= 0) - __up(sem); -} - -#endif -#endif /* __ASM_SH_SEMAPHORE_H */ +#include diff --git a/include/asm-sparc/semaphore.h b/include/asm-sparc/semaphore.h index 8018f9f4d497..d9b2034ed1d2 100644 --- a/include/asm-sparc/semaphore.h +++ b/include/asm-sparc/semaphore.h @@ -1,192 +1 @@ -#ifndef _SPARC_SEMAPHORE_H -#define _SPARC_SEMAPHORE_H - -/* Dinky, good for nothing, just barely irq safe, Sparc semaphores. */ - -#ifdef __KERNEL__ - -#include -#include -#include - -struct semaphore { - atomic24_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC24_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic24_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore * sem); -extern int __down_interruptible(struct semaphore * sem); -extern int __down_trylock(struct semaphore * sem); -extern void __up(struct semaphore * sem); - -static inline void down(struct semaphore * sem) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - - might_sleep(); - - ptr = &(sem->count.counter); - increment = 1; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_sub\n\t" - " add %%o7, 8, %%o7\n\t" - "tst %%g2\n\t" - "bl 2f\n\t" - " nop\n" - "1:\n\t" - ".subsection 2\n" - "2:\n\t" - "save %%sp, -64, %%sp\n\t" - "mov %%g1, %%l1\n\t" - "mov %%g5, %%l5\n\t" - "call %3\n\t" - " mov %%g1, %%o0\n\t" - "mov %%l1, %%g1\n\t" - "ba 1b\n\t" - " restore %%l5, %%g0, %%g5\n\t" - ".previous\n" - : "=&r" (increment) - : "0" (increment), "r" (ptr), "i" (__down) - : "g3", "g4", "g7", "memory", "cc"); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - - might_sleep(); - - ptr = &(sem->count.counter); - increment = 1; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_sub\n\t" - " add %%o7, 8, %%o7\n\t" - "tst %%g2\n\t" - "bl 2f\n\t" - " clr %%g2\n" - "1:\n\t" - ".subsection 2\n" - "2:\n\t" - "save %%sp, -64, %%sp\n\t" - "mov %%g1, %%l1\n\t" - "mov %%g5, %%l5\n\t" - "call %3\n\t" - " mov %%g1, %%o0\n\t" - "mov %%l1, %%g1\n\t" - "mov %%l5, %%g5\n\t" - "ba 1b\n\t" - " restore %%o0, %%g0, %%g2\n\t" - ".previous\n" - : "=&r" (increment) - : "0" (increment), "r" (ptr), "i" (__down_interruptible) - : "g3", "g4", "g7", "memory", "cc"); - - return increment; -} - -static inline int down_trylock(struct semaphore * sem) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - - ptr = &(sem->count.counter); - increment = 1; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_sub\n\t" - " add %%o7, 8, %%o7\n\t" - "tst %%g2\n\t" - "bl 2f\n\t" - " clr %%g2\n" - "1:\n\t" - ".subsection 2\n" - "2:\n\t" - "save %%sp, -64, %%sp\n\t" - "mov %%g1, %%l1\n\t" - "mov %%g5, %%l5\n\t" - "call %3\n\t" - " mov %%g1, %%o0\n\t" - "mov %%l1, %%g1\n\t" - "mov %%l5, %%g5\n\t" - "ba 1b\n\t" - " restore %%o0, %%g0, %%g2\n\t" - ".previous\n" - : "=&r" (increment) - : "0" (increment), "r" (ptr), "i" (__down_trylock) - : "g3", "g4", "g7", "memory", "cc"); - - return increment; -} - -static inline void up(struct semaphore * sem) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - - ptr = &(sem->count.counter); - increment = 1; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_add\n\t" - " add %%o7, 8, %%o7\n\t" - "tst %%g2\n\t" - "ble 2f\n\t" - " nop\n" - "1:\n\t" - ".subsection 2\n" - "2:\n\t" - "save %%sp, -64, %%sp\n\t" - "mov %%g1, %%l1\n\t" - "mov %%g5, %%l5\n\t" - "call %3\n\t" - " mov %%g1, %%o0\n\t" - "mov %%l1, %%g1\n\t" - "ba 1b\n\t" - " restore %%l5, %%g0, %%g5\n\t" - ".previous\n" - : "=&r" (increment) - : "0" (increment), "r" (ptr), "i" (__up) - : "g3", "g4", "g7", "memory", "cc"); -} - -#endif /* __KERNEL__ */ - -#endif /* !(_SPARC_SEMAPHORE_H) */ +#include diff --git a/include/asm-sparc64/semaphore.h b/include/asm-sparc64/semaphore.h index 7f7c0c4e024f..d9b2034ed1d2 100644 --- a/include/asm-sparc64/semaphore.h +++ b/include/asm-sparc64/semaphore.h @@ -1,53 +1 @@ -#ifndef _SPARC64_SEMAPHORE_H -#define _SPARC64_SEMAPHORE_H - -/* These are actually reasonable on the V9. - * - * See asm-ppc/semaphore.h for implementation commentary, - * only sparc64 specific issues are commented here. - */ -#ifdef __KERNEL__ - -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, count) \ - { ATOMIC_INIT(count), \ - __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) } - -#define __DECLARE_SEMAPHORE_GENERIC(name, count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void up(struct semaphore *sem); -extern void down(struct semaphore *sem); -extern int down_trylock(struct semaphore *sem); -extern int down_interruptible(struct semaphore *sem); - -#endif /* __KERNEL__ */ - -#endif /* !(_SPARC64_SEMAPHORE_H) */ +#include diff --git a/include/asm-um/semaphore.h b/include/asm-um/semaphore.h index ff13c34de421..d9b2034ed1d2 100644 --- a/include/asm-um/semaphore.h +++ b/include/asm-um/semaphore.h @@ -1,6 +1 @@ -#ifndef __UM_SEMAPHORE_H -#define __UM_SEMAPHORE_H - -#include "asm/arch/semaphore.h" - -#endif +#include diff --git a/include/asm-v850/semaphore.h b/include/asm-v850/semaphore.h index 10ed0ccf37df..d9b2034ed1d2 100644 --- a/include/asm-v850/semaphore.h +++ b/include/asm-v850/semaphore.h @@ -1,84 +1 @@ -#ifndef __V850_SEMAPHORE_H__ -#define __V850_SEMAPHORE_H__ - -#include -#include -#include -#include - -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name,count) \ - { ATOMIC_INIT (count), 0, \ - __WAIT_QUEUE_HEAD_INITIALIZER ((name).wait) } - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER (name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC (name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init (sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init (sem, 0); -} - -/* - * special register calling convention - */ -asmlinkage void __down_failed (void); -asmlinkage int __down_interruptible_failed (void); -asmlinkage int __down_trylock_failed (void); -asmlinkage void __up_wakeup (void); - -extern void __down (struct semaphore * sem); -extern int __down_interruptible (struct semaphore * sem); -extern int __down_trylock (struct semaphore * sem); -extern void __up (struct semaphore * sem); - -static inline void down (struct semaphore * sem) -{ - might_sleep(); - if (atomic_dec_return (&sem->count) < 0) - __down (sem); -} - -static inline int down_interruptible (struct semaphore * sem) -{ - int ret = 0; - might_sleep(); - if (atomic_dec_return (&sem->count) < 0) - ret = __down_interruptible (sem); - return ret; -} - -static inline int down_trylock (struct semaphore *sem) -{ - int ret = 0; - if (atomic_dec_return (&sem->count) < 0) - ret = __down_trylock (sem); - return ret; -} - -static inline void up (struct semaphore * sem) -{ - if (atomic_inc_return (&sem->count) <= 0) - __up (sem); -} - -#endif /* __V850_SEMAPHORE_H__ */ +#include diff --git a/include/asm-x86/semaphore.h b/include/asm-x86/semaphore.h index 572c0b67a6b0..d9b2034ed1d2 100644 --- a/include/asm-x86/semaphore.h +++ b/include/asm-x86/semaphore.h @@ -1,5 +1 @@ -#ifdef CONFIG_X86_32 -# include "semaphore_32.h" -#else -# include "semaphore_64.h" -#endif +#include diff --git a/include/asm-x86/semaphore_32.h b/include/asm-x86/semaphore_32.h deleted file mode 100644 index ac96d3804d0c..000000000000 --- a/include/asm-x86/semaphore_32.h +++ /dev/null @@ -1,175 +0,0 @@ -#ifndef _I386_SEMAPHORE_H -#define _I386_SEMAPHORE_H - -#include - -#ifdef __KERNEL__ - -/* - * SMP- and interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * Modified 1996-12-23 by Dave Grothe to fix bugs in - * the original code and to make semaphore waits - * interruptible so that processes waiting on - * semaphores can be killed. - * Modified 1999-02-14 by Andrea Arcangeli, split the sched.c helper - * functions in asm/sempahore-helper.h while fixing a - * potential and subtle race discovered by Ulrich Schmid - * in down_interruptible(). Since I started to play here I - * also implemented the `trylock' semaphore operation. - * 1999-07-02 Artur Skawina - * Optimized "0(ecx)" -> "(ecx)" (the assembler does not - * do this). Changed calling sequences from push/jmp to - * traditional call/ret. - * Modified 2001-01-01 Andreas Franck - * Some hacks to ensure compatibility with recent - * GCC snapshots, to avoid stack corruption when compiling - * with -fomit-frame-pointer. It's not sure if this will - * be fixed in GCC, as our previous implementation was a - * bit dubious. - * - * If you would like to see an analysis of this implementation, please - * ftp to gcom.com and download the file - * /pub/linux/src/semaphore/semaphore-2.0.24.tar.gz. - * - */ - -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesn't. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern asmregparm void __down_failed(atomic_t *count_ptr); -extern asmregparm int __down_failed_interruptible(atomic_t *count_ptr); -extern asmregparm int __down_failed_trylock(atomic_t *count_ptr); -extern asmregparm void __up_wakeup(atomic_t *count_ptr); - -/* - * This is ugly, but we want the default case to fall through. - * "__down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/i386/kernel/semaphore.c - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - __asm__ __volatile__( - "# atomic down operation\n\t" - LOCK_PREFIX "decl %0\n\t" /* --sem->count */ - "jns 2f\n" - "\tlea %0,%%eax\n\t" - "call __down_failed\n" - "2:" - :"+m" (sem->count) - : - :"memory","ax"); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int result; - - might_sleep(); - __asm__ __volatile__( - "# atomic interruptible down operation\n\t" - "xorl %0,%0\n\t" - LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "jns 2f\n\t" - "lea %1,%%eax\n\t" - "call __down_failed_interruptible\n" - "2:" - :"=&a" (result), "+m" (sem->count) - : - :"memory"); - return result; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - int result; - - __asm__ __volatile__( - "# atomic interruptible down operation\n\t" - "xorl %0,%0\n\t" - LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "jns 2f\n\t" - "lea %1,%%eax\n\t" - "call __down_failed_trylock\n\t" - "2:\n" - :"=&a" (result), "+m" (sem->count) - : - :"memory"); - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - */ -static inline void up(struct semaphore * sem) -{ - __asm__ __volatile__( - "# atomic up operation\n\t" - LOCK_PREFIX "incl %0\n\t" /* ++sem->count */ - "jg 1f\n\t" - "lea %0,%%eax\n\t" - "call __up_wakeup\n" - "1:" - :"+m" (sem->count) - : - :"memory","ax"); -} - -#endif -#endif diff --git a/include/asm-x86/semaphore_64.h b/include/asm-x86/semaphore_64.h deleted file mode 100644 index 79694306bf7d..000000000000 --- a/include/asm-x86/semaphore_64.h +++ /dev/null @@ -1,180 +0,0 @@ -#ifndef _X86_64_SEMAPHORE_H -#define _X86_64_SEMAPHORE_H - -#include - -#ifdef __KERNEL__ - -/* - * SMP- and interrupt-safe semaphores.. - * - * (C) Copyright 1996 Linus Torvalds - * - * Modified 1996-12-23 by Dave Grothe to fix bugs in - * the original code and to make semaphore waits - * interruptible so that processes waiting on - * semaphores can be killed. - * Modified 1999-02-14 by Andrea Arcangeli, split the sched.c helper - * functions in asm/sempahore-helper.h while fixing a - * potential and subtle race discovered by Ulrich Schmid - * in down_interruptible(). Since I started to play here I - * also implemented the `trylock' semaphore operation. - * 1999-07-02 Artur Skawina - * Optimized "0(ecx)" -> "(ecx)" (the assembler does not - * do this). Changed calling sequences from push/jmp to - * traditional call/ret. - * Modified 2001-01-01 Andreas Franck - * Some hacks to ensure compatibility with recent - * GCC snapshots, to avoid stack corruption when compiling - * with -fomit-frame-pointer. It's not sure if this will - * be fixed in GCC, as our previous implementation was a - * bit dubious. - * - * If you would like to see an analysis of this implementation, please - * ftp to gcom.com and download the file - * /pub/linux/src/semaphore/semaphore-2.0.24.tar.gz. - * - */ - -#include -#include -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesn't. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* - * This is ugly, but we want the default case to fall through. - * "__down_failed" is a special asm handler that calls the C - * routine that actually waits. See arch/x86_64/kernel/semaphore.c - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - - __asm__ __volatile__( - "# atomic down operation\n\t" - LOCK_PREFIX "decl %0\n\t" /* --sem->count */ - "jns 1f\n\t" - "call __down_failed\n" - "1:" - :"=m" (sem->count) - :"D" (sem) - :"memory"); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int result; - - might_sleep(); - - __asm__ __volatile__( - "# atomic interruptible down operation\n\t" - "xorl %0,%0\n\t" - LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "jns 2f\n\t" - "call __down_failed_interruptible\n" - "2:\n" - :"=&a" (result), "=m" (sem->count) - :"D" (sem) - :"memory"); - return result; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - int result; - - __asm__ __volatile__( - "# atomic interruptible down operation\n\t" - "xorl %0,%0\n\t" - LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "jns 2f\n\t" - "call __down_failed_trylock\n\t" - "2:\n" - :"=&a" (result), "=m" (sem->count) - :"D" (sem) - :"memory","cc"); - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - __asm__ __volatile__( - "# atomic up operation\n\t" - LOCK_PREFIX "incl %0\n\t" /* ++sem->count */ - "jg 1f\n\t" - "call __up_wakeup\n" - "1:" - :"=m" (sem->count) - :"D" (sem) - :"memory"); -} -#endif /* __KERNEL__ */ -#endif diff --git a/include/asm-xtensa/semaphore.h b/include/asm-xtensa/semaphore.h index 3e04167cd9dc..d9b2034ed1d2 100644 --- a/include/asm-xtensa/semaphore.h +++ b/include/asm-xtensa/semaphore.h @@ -1,99 +1 @@ -/* - * linux/include/asm-xtensa/semaphore.h - * - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * Copyright (C) 2001 - 2005 Tensilica Inc. - */ - -#ifndef _XTENSA_SEMAPHORE_H -#define _XTENSA_SEMAPHORE_H - -#include -#include -#include -#include - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name,n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -static inline void init_MUTEX (struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED (struct semaphore *sem) -{ - sema_init(sem, 0); -} - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -extern spinlock_t semaphore_wake_lock; - -static inline void down(struct semaphore * sem) -{ - might_sleep(); - - if (atomic_sub_return(1, &sem->count) < 0) - __down(sem); -} - -static inline int down_interruptible(struct semaphore * sem) -{ - int ret = 0; - - might_sleep(); - - if (atomic_sub_return(1, &sem->count) < 0) - ret = __down_interruptible(sem); - return ret; -} - -static inline int down_trylock(struct semaphore * sem) -{ - int ret = 0; - - if (atomic_sub_return(1, &sem->count) < 0) - ret = __down_trylock(sem); - return ret; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - */ -static inline void up(struct semaphore * sem) -{ - if (atomic_add_return(1, &sem->count) <= 0) - __up(sem); -} - -#endif /* _XTENSA_SEMAPHORE_H */ +#include diff --git a/include/linux/semaphore.h b/include/linux/semaphore.h new file mode 100644 index 000000000000..b3c691b089b2 --- /dev/null +++ b/include/linux/semaphore.h @@ -0,0 +1,77 @@ +/* + * Copyright (c) 2008 Intel Corporation + * Author: Matthew Wilcox + * + * Distributed under the terms of the GNU GPL, version 2 + * + * Counting semaphores allow up to tasks to acquire the semaphore + * simultaneously. + */ +#ifndef __LINUX_SEMAPHORE_H +#define __LINUX_SEMAPHORE_H + +#include +#include + +/* + * The spinlock controls access to the other members of the semaphore. + * 'count' is decremented by every task which calls down*() and incremented + * by every call to up(). Thus, if it is positive, it indicates how many + * more tasks may acquire the lock. If it is negative, it indicates how + * many tasks are waiting for the lock. Tasks waiting for the lock are + * kept on the wait_list. + */ +struct semaphore { + spinlock_t lock; + int count; + struct list_head wait_list; +}; + +#define __SEMAPHORE_INITIALIZER(name, n) \ +{ \ + .lock = __SPIN_LOCK_UNLOCKED((name).lock), \ + .count = n, \ + .wait_list = LIST_HEAD_INIT((name).wait_list), \ +} + +#define __DECLARE_SEMAPHORE_GENERIC(name, count) \ + struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) + +#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) + +static inline void sema_init(struct semaphore *sem, int val) +{ + static struct lock_class_key __key; + *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); + lockdep_init_map(&sem->lock.dep_map, "semaphore->lock", &__key, 0); +} + +#define init_MUTEX(sem) sema_init(sem, 1) +#define init_MUTEX_LOCKED(sem) sema_init(sem, 0) + +/* + * Attempt to acquire the semaphore. If another task is already holding the + * semaphore, sleep until the semaphore is released. + */ +extern void down(struct semaphore *sem); + +/* + * As down(), except the sleep may be interrupted by a signal. If it is, + * this function will return -EINTR. + */ +extern int __must_check down_interruptible(struct semaphore *sem); + +/* + * As down(), except this function will not sleep. It will return 0 if it + * acquired the semaphore and 1 if the semaphore was contended. This + * function may be called from any context, including interrupt and softirq. + */ +extern int __must_check down_trylock(struct semaphore *sem); + +/* + * Release the semaphore. Unlike mutexes, up() may be called from any + * context and even by tasks which have never called down(). + */ +extern void up(struct semaphore *sem); + +#endif /* __LINUX_SEMAPHORE_H */ -- cgit v1.2.3 From f06d96865861c3dd01520f47e2e61c899db1631f Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 14 Mar 2008 13:19:33 -0400 Subject: Introduce down_killable() down_killable() is the functional counterpart of mutex_lock_killable. Signed-off-by: Matthew Wilcox --- include/linux/semaphore.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include') diff --git a/include/linux/semaphore.h b/include/linux/semaphore.h index b3c691b089b2..88f2a28cc0f1 100644 --- a/include/linux/semaphore.h +++ b/include/linux/semaphore.h @@ -61,6 +61,12 @@ extern void down(struct semaphore *sem); */ extern int __must_check down_interruptible(struct semaphore *sem); +/* + * As down_interruptible(), except the sleep may only be interrupted by + * signals which are fatal to this process. + */ +extern int __must_check down_killable(struct semaphore *sem); + /* * As down(), except this function will not sleep. It will return 0 if it * acquired the semaphore and 1 if the semaphore was contended. This -- cgit v1.2.3 From f1241c87a16c4fe9f4f51d6ed3589f031c505e8d Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 14 Mar 2008 13:43:13 -0400 Subject: Add down_timeout and change ACPI to use it ACPI currently emulates a timeout for semaphores with calls to down_trylock and sleep. This produces horrible behaviour in terms of fairness and excessive wakeups. Now that we have a unified semaphore implementation, adding a real down_trylock is almost trivial. Signed-off-by: Matthew Wilcox --- include/linux/semaphore.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include') diff --git a/include/linux/semaphore.h b/include/linux/semaphore.h index 88f2a28cc0f1..a107aebd9148 100644 --- a/include/linux/semaphore.h +++ b/include/linux/semaphore.h @@ -74,6 +74,12 @@ extern int __must_check down_killable(struct semaphore *sem); */ extern int __must_check down_trylock(struct semaphore *sem); +/* + * As down(), except this function will return -ETIME if it fails to + * acquire the semaphore within the specified number of jiffies. + */ +extern int __must_check down_timeout(struct semaphore *sem, long jiffies); + /* * Release the semaphore. Unlike mutexes, up() may be called from any * context and even by tasks which have never called down(). -- cgit v1.2.3 From b17170b2fac96705db3188f093f89e8e838418e4 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 14 Mar 2008 14:35:22 -0400 Subject: Simplify semaphore implementation By removing the negative values of 'count' and relying on the wait_list to indicate whether we have any waiters, we can simplify the implementation by removing the protection against an unlikely race condition. Thanks to David Howells for his suggestions. Signed-off-by: Matthew Wilcox --- include/linux/semaphore.h | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/semaphore.h b/include/linux/semaphore.h index a107aebd9148..a7125daaff90 100644 --- a/include/linux/semaphore.h +++ b/include/linux/semaphore.h @@ -15,15 +15,12 @@ /* * The spinlock controls access to the other members of the semaphore. - * 'count' is decremented by every task which calls down*() and incremented - * by every call to up(). Thus, if it is positive, it indicates how many - * more tasks may acquire the lock. If it is negative, it indicates how - * many tasks are waiting for the lock. Tasks waiting for the lock are - * kept on the wait_list. + * 'count' represents how many more tasks can acquire this semaphore. + * Tasks waiting for the lock are kept on the wait_list. */ struct semaphore { spinlock_t lock; - int count; + unsigned int count; struct list_head wait_list; }; -- cgit v1.2.3 From 714493cd5468f42ca3c4f730a9c17c203abd5059 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 11 Apr 2008 15:23:52 -0400 Subject: Improve semaphore documentation Move documentation from semaphore.h to semaphore.c as requested by Andrew Morton. Also reformat to kernel-doc style and add some more notes about the implementation. Signed-off-by: Matthew Wilcox --- include/linux/semaphore.h | 39 ++------------------------------------- 1 file changed, 2 insertions(+), 37 deletions(-) (limited to 'include') diff --git a/include/linux/semaphore.h b/include/linux/semaphore.h index a7125daaff90..9cae64b00d6b 100644 --- a/include/linux/semaphore.h +++ b/include/linux/semaphore.h @@ -4,8 +4,7 @@ * * Distributed under the terms of the GNU GPL, version 2 * - * Counting semaphores allow up to tasks to acquire the semaphore - * simultaneously. + * Please see kernel/semaphore.c for documentation of these functions */ #ifndef __LINUX_SEMAPHORE_H #define __LINUX_SEMAPHORE_H @@ -13,11 +12,7 @@ #include #include -/* - * The spinlock controls access to the other members of the semaphore. - * 'count' represents how many more tasks can acquire this semaphore. - * Tasks waiting for the lock are kept on the wait_list. - */ +/* Please don't access any members of this structure directly */ struct semaphore { spinlock_t lock; unsigned int count; @@ -46,41 +41,11 @@ static inline void sema_init(struct semaphore *sem, int val) #define init_MUTEX(sem) sema_init(sem, 1) #define init_MUTEX_LOCKED(sem) sema_init(sem, 0) -/* - * Attempt to acquire the semaphore. If another task is already holding the - * semaphore, sleep until the semaphore is released. - */ extern void down(struct semaphore *sem); - -/* - * As down(), except the sleep may be interrupted by a signal. If it is, - * this function will return -EINTR. - */ extern int __must_check down_interruptible(struct semaphore *sem); - -/* - * As down_interruptible(), except the sleep may only be interrupted by - * signals which are fatal to this process. - */ extern int __must_check down_killable(struct semaphore *sem); - -/* - * As down(), except this function will not sleep. It will return 0 if it - * acquired the semaphore and 1 if the semaphore was contended. This - * function may be called from any context, including interrupt and softirq. - */ extern int __must_check down_trylock(struct semaphore *sem); - -/* - * As down(), except this function will return -ETIME if it fails to - * acquire the semaphore within the specified number of jiffies. - */ extern int __must_check down_timeout(struct semaphore *sem, long jiffies); - -/* - * Release the semaphore. Unlike mutexes, up() may be called from any - * context and even by tasks which have never called down(). - */ extern void up(struct semaphore *sem); #endif /* __LINUX_SEMAPHORE_H */ -- cgit v1.2.3