diff options
Diffstat (limited to 'include/asm-alpha/spinlock.h')
| -rw-r--r-- | include/asm-alpha/spinlock.h | 158 |
1 files changed, 138 insertions, 20 deletions
diff --git a/include/asm-alpha/spinlock.h b/include/asm-alpha/spinlock.h index a38477426..1c7afd449 100644 --- a/include/asm-alpha/spinlock.h +++ b/include/asm-alpha/spinlock.h @@ -45,7 +45,10 @@ typedef struct { int dummy; } rwlock_t; #define write_lock_irqsave(lock, flags) do { (flags) = swpipl(7); } while (0) #define write_unlock_irqrestore(lock, flags) setipl(flags) -#else +#else /* __SMP__ */ + +#include <linux/kernel.h> +#include <asm/current.h> /* Simple spin lock operations. There are two variants, one clears IRQ's * on the local processor, one does not. @@ -56,12 +59,15 @@ typedef struct { int dummy; } rwlock_t; typedef struct { volatile unsigned long lock; unsigned long previous; + unsigned long task; } spinlock_t; #define SPIN_LOCK_UNLOCKED { 0, 0 } -#define spin_lock_init(lock) do { (lock)->lock = 0; (lock)->previous = 0; } while(0) -#define spin_unlock_wait(lock) do { barrier(); } while(((volatile spinlock_t *)lock)->lock) +#define spin_lock_init(x) \ + do { (x)->lock = 0; (x)->previous = 0; } while(0) +#define spin_unlock_wait(x) \ + do { barrier(); } while(((volatile spinlock_t *)x)->lock) typedef struct { unsigned long a[100]; } __dummy_lock_t; #define __dummy_lock(lock) (*(__dummy_lock_t *)(lock)) @@ -73,40 +79,38 @@ static inline void spin_unlock(spinlock_t * lock) :"=m" (__dummy_lock(lock))); } +#if 1 +#define DEBUG_SPINLOCK +#else +#undef DEBUG_SPINLOCK +#endif + +#ifdef DEBUG_SPINLOCK +extern void spin_lock(spinlock_t * lock); +#else static inline void spin_lock(spinlock_t * lock) { - __label__ l1; long tmp; - long stuck = 0x100000000; -l1: + /* Use sub-sections to put the actual loop at the end of this object file's text section so as to perfect branch prediction. */ __asm__ __volatile__( "1: ldq_l %0,%1\n" - " subq %2,1,%2\n" " blbs %0,2f\n" " or %0,1,%0\n" " stq_c %0,%1\n" - " beq %0,3f\n" + " beq %0,2f\n" "4: mb\n" ".section .text2,\"ax\"\n" "2: ldq %0,%1\n" - " subq %2,1,%2\n" - "3: blt %2,4b\n" " blbs %0,2b\n" " br 1b\n" ".previous" : "=r" (tmp), - "=m" (__dummy_lock(lock)), - "=r" (stuck) - : "2" (stuck)); - - if (stuck < 0) - printk("spinlock stuck at %p (%lx)\n",&&l1,lock->previous); - else - lock->previous = (unsigned long) &&l1; + "=m" (__dummy_lock(lock))); } +#endif /* DEBUG_SPINLOCK */ #define spin_trylock(lock) (!test_and_set_bit(0,(lock))) @@ -117,10 +121,124 @@ l1: do { spin_unlock(lock); __sti(); } while (0) #define spin_lock_irqsave(lock, flags) \ - do { flags = swpipl(7); spin_lock(lock); } while (0) + do { __save_and_cli(flags); spin_lock(lock); } while (0) #define spin_unlock_irqrestore(lock, flags) \ - do { spin_unlock(lock); setipl(flags); } while (0) + do { spin_unlock(lock); __restore_flags(flags); } while (0) + +/***********************************************************/ + +#if 1 +#define DEBUG_RWLOCK +#else +#undef DEBUG_RWLOCK +#endif + +typedef struct { volatile int write_lock:1, read_counter:31; } rwlock_t; + +#define RW_LOCK_UNLOCKED { 0, 0 } + +#ifdef DEBUG_RWLOCK +extern void write_lock(rwlock_t * lock); +#else +static inline void write_lock(rwlock_t * lock) +{ + long regx, regy; + + __asm__ __volatile__( + "1: ldl_l %1,%0;" + " blbs %1,6f;" + " or %1,1,%2;" + " stl_c %2,%0;" + " beq %2,6f;" + " blt %1,8f;" + "4: mb\n" + ".section .text2,\"ax\"\n" + "6: ldl %1,%0;" + " blbs %1,6b;" + " br 1b;" + "8: ldl %1,%0;" + " blt %1,8b;" + "9: br 4b\n" + ".previous" + : "=m" (__dummy_lock(lock)), "=&r" (regx), "=&r" (regy) + : "0" (__dummy_lock(lock)) + ); +} +#endif /* DEBUG_RWLOCK */ + +static inline void write_unlock(rwlock_t * lock) +{ + __asm__ __volatile__("mb; stl $31,%0" : "=m" (__dummy_lock(lock))); +} + +#ifdef DEBUG_RWLOCK +extern void _read_lock(rwlock_t * lock); +#else +static inline void _read_lock(rwlock_t * lock) +{ + long regx; + + __asm__ __volatile__( + "1: ldl_l %1,%0;" + " blbs %1,6f;" + " subl %1,2,%1;" + " stl_c %1,%0;" + " beq %1,6f;" + "4: mb\n" + ".section .text2,\"ax\"\n" + "6: ldl %1,%0;" + " blbs %1,6b;" + " br 1b\n" + ".previous" + : "=m" (__dummy_lock(lock)), "=&r" (regx) + : "0" (__dummy_lock(lock)) + ); +} +#endif /* DEBUG_RWLOCK */ + +#define read_lock(lock) \ +do { unsigned long flags; \ + __save_and_cli(flags); \ + _read_lock(lock); \ + __restore_flags(flags); \ +} while(0) + +static inline void _read_unlock(rwlock_t * lock) +{ + long regx; + __asm__ __volatile__( + "1: ldl_l %1,%0;" + " addl %1,2,%1;" + " stl_c %1,%0;" + " beq %1,6f;" + ".section .text2,\"ax\"\n" + "6: br 1b\n" + ".previous" + : "=m" (__dummy_lock(lock)), "=&r" (regx) + : "0" (__dummy_lock(lock))); +} + +#define read_unlock(lock) \ +do { unsigned long flags; \ + __save_and_cli(flags); \ + _read_unlock(lock); \ + __restore_flags(flags); \ +} while(0) + +#define read_lock_irq(lock) do { __cli(); _read_lock(lock); } while (0) +#define read_unlock_irq(lock) do { _read_unlock(lock); __sti(); } while (0) +#define write_lock_irq(lock) do { __cli(); write_lock(lock); } while (0) +#define write_unlock_irq(lock) do { write_unlock(lock); __sti(); } while (0) + +#define read_lock_irqsave(lock, flags) \ + do { __save_and_cli(flags); _read_lock(lock); } while (0) +#define read_unlock_irqrestore(lock, flags) \ + do { _read_unlock(lock); __restore_flags(flags); } while (0) +#define write_lock_irqsave(lock, flags) \ + do { __save_and_cli(flags); write_lock(lock); } while (0) +#define write_unlock_irqrestore(lock, flags) \ + do { write_unlock(lock); __restore_flags(flags); } while (0) #endif /* SMP */ #endif /* _ALPHA_SPINLOCK_H */ |