diff options
Diffstat (limited to 'include/linux/spinlock.h')
| -rw-r--r-- | include/linux/spinlock.h | 86 |
1 files changed, 79 insertions, 7 deletions
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h index dc27910a6ad5..6e3ef75fd885 100644 --- a/include/linux/spinlock.h +++ b/include/linux/spinlock.h @@ -2,6 +2,10 @@ #define __LINUX_SPINLOCK_H #include <linux/config.h> +#include <linux/linkage.h> +#include <linux/compiler.h> +#include <linux/thread_info.h> +#include <linux/kernel.h> /* * These are the generic versions of the spinlocks and read-write @@ -62,8 +66,10 @@ #if (DEBUG_SPINLOCKS < 1) +#ifndef CONFIG_PREEMPT #define atomic_dec_and_lock(atomic,lock) atomic_dec_and_test(atomic) #define ATOMIC_DEC_AND_LOCK +#endif /* * Your basic spinlocks, allowing only a single CPU anywhere @@ -79,11 +85,11 @@ #endif #define spin_lock_init(lock) do { } while(0) -#define spin_lock(lock) (void)(lock) /* Not "unused variable". */ +#define _raw_spin_lock(lock) (void)(lock) /* Not "unused variable". */ #define spin_is_locked(lock) (0) -#define spin_trylock(lock) ({1; }) +#define _raw_spin_trylock(lock) ({1; }) #define spin_unlock_wait(lock) do { } while(0) -#define spin_unlock(lock) do { } while(0) +#define _raw_spin_unlock(lock) do { } while(0) #elif (DEBUG_SPINLOCKS < 2) @@ -142,13 +148,79 @@ typedef struct { #endif #define rwlock_init(lock) do { } while(0) -#define read_lock(lock) (void)(lock) /* Not "unused variable". */ -#define read_unlock(lock) do { } while(0) -#define write_lock(lock) (void)(lock) /* Not "unused variable". */ -#define write_unlock(lock) do { } while(0) +#define _raw_read_lock(lock) (void)(lock) /* Not "unused variable". */ +#define _raw_read_unlock(lock) do { } while(0) +#define _raw_write_lock(lock) (void)(lock) /* Not "unused variable". */ +#define _raw_write_unlock(lock) do { } while(0) #endif /* !SMP */ +#ifdef CONFIG_PREEMPT + +asmlinkage void preempt_schedule(void); + +#define preempt_get_count() (current_thread_info()->preempt_count) + +#define preempt_disable() \ +do { \ + ++current_thread_info()->preempt_count; \ + barrier(); \ +} while (0) + +#define preempt_enable_no_resched() \ +do { \ + --current_thread_info()->preempt_count; \ + barrier(); \ +} while (0) + +#define preempt_enable() \ +do { \ + --current_thread_info()->preempt_count; \ + barrier(); \ + if (unlikely(!(current_thread_info()->preempt_count) && \ + test_thread_flag(TIF_NEED_RESCHED))) \ + preempt_schedule(); \ +} while (0) + +#define spin_lock(lock) \ +do { \ + preempt_disable(); \ + _raw_spin_lock(lock); \ +} while(0) + +#define spin_trylock(lock) ({preempt_disable(); _raw_spin_trylock(lock) ? \ + 1 : ({preempt_enable(); 0;});}) +#define spin_unlock(lock) \ +do { \ + _raw_spin_unlock(lock); \ + preempt_enable(); \ +} while (0) + +#define read_lock(lock) ({preempt_disable(); _raw_read_lock(lock);}) +#define read_unlock(lock) ({_raw_read_unlock(lock); preempt_enable();}) +#define write_lock(lock) ({preempt_disable(); _raw_write_lock(lock);}) +#define write_unlock(lock) ({_raw_write_unlock(lock); preempt_enable();}) +#define write_trylock(lock) ({preempt_disable();_raw_write_trylock(lock) ? \ + 1 : ({preempt_enable(); 0;});}) + +#else + +#define preempt_get_count() do { } while (0) +#define preempt_disable() do { } while (0) +#define preempt_enable_no_resched() do {} while(0) +#define preempt_enable() do { } while (0) + +#define spin_lock(lock) _raw_spin_lock(lock) +#define spin_trylock(lock) _raw_spin_trylock(lock) +#define spin_unlock(lock) _raw_spin_unlock(lock) + +#define read_lock(lock) _raw_read_lock(lock) +#define read_unlock(lock) _raw_read_unlock(lock) +#define write_lock(lock) _raw_write_lock(lock) +#define write_unlock(lock) _raw_write_unlock(lock) +#define write_trylock(lock) _raw_write_trylock(lock) +#endif + /* "lock on reference count zero" */ #ifndef ATOMIC_DEC_AND_LOCK #include <asm/atomic.h> |