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Diffstat (limited to 'src/recompiler/qemu-lock.h')
| -rw-r--r-- | src/recompiler/qemu-lock.h | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/src/recompiler/qemu-lock.h b/src/recompiler/qemu-lock.h new file mode 100644 index 00000000..1234a5b6 --- /dev/null +++ b/src/recompiler/qemu-lock.h @@ -0,0 +1,261 @@ +/* + * Copyright (c) 2003 Fabrice Bellard + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/> + */ + +/* + * Oracle LGPL Disclaimer: For the avoidance of doubt, except that if any license choice + * other than GPL or LGPL is available it will apply instead, Oracle elects to use only + * the Lesser General Public License version 2.1 (LGPLv2) at this time for any software where + * a choice of LGPL license versions is made available with the language indicating + * that LGPLv2 or any later version may be used, or where a choice of which version + * of the LGPL is applied is otherwise unspecified. + */ + +/* Locking primitives. Most of this code should be redundant - + system emulation doesn't need/use locking, NPTL userspace uses + pthread mutexes, and non-NPTL userspace isn't threadsafe anyway. + In either case a spinlock is probably the wrong kind of lock. + Spinlocks are only good if you know annother CPU has the lock and is + likely to release it soon. In environments where you have more threads + than physical CPUs (the extreme case being a single CPU host) a spinlock + simply wastes CPU until the OS decides to preempt it. */ +#if defined(CONFIG_USE_NPTL) + +#include <pthread.h> +#define spin_lock pthread_mutex_lock +#define spin_unlock pthread_mutex_unlock +#define spinlock_t pthread_mutex_t +#define SPIN_LOCK_UNLOCKED PTHREAD_MUTEX_INITIALIZER + +#else + +#if defined(__hppa__) + +typedef int spinlock_t[4]; + +#define SPIN_LOCK_UNLOCKED { 1, 1, 1, 1 } + +static inline void resetlock (spinlock_t *p) +{ + (*p)[0] = (*p)[1] = (*p)[2] = (*p)[3] = 1; +} + +#else + +typedef int spinlock_t; + +#define SPIN_LOCK_UNLOCKED 0 + +static inline void resetlock (spinlock_t *p) +{ + *p = SPIN_LOCK_UNLOCKED; +} + +#endif + +#ifdef VBOX +DECLINLINE(int) testandset (int *p) +{ + return ASMAtomicCmpXchgU32((volatile uint32_t *)p, 1, 0) ? 0 : 1; +} +#elif defined(_ARCH_PPC) +static inline int testandset (int *p) +{ + int ret; + __asm__ __volatile__ ( + " lwarx %0,0,%1\n" + " xor. %0,%3,%0\n" + " bne $+12\n" + " stwcx. %2,0,%1\n" + " bne- $-16\n" + : "=&r" (ret) + : "r" (p), "r" (1), "r" (0) + : "cr0", "memory"); + return ret; +} +#elif defined(__i386__) +static inline int testandset (int *p) +{ + long int readval = 0; + + __asm__ __volatile__ ("lock; cmpxchgl %2, %0" + : "+m" (*p), "+a" (readval) + : "r" (1) + : "cc"); + return readval; +} +#elif defined(__x86_64__) +static inline int testandset (int *p) +{ + long int64_t readval = 0; + + __asm__ __volatile__ ("lock; cmpxchgl %2, %0" + : "+m" (*p), "+a" (readval) + : "r" (1) + : "cc"); + return readval; +} +#elif defined(__s390__) +static inline int testandset (int *p) +{ + int ret; + + __asm__ __volatile__ ("0: cs %0,%1,0(%2)\n" + " jl 0b" + : "=&d" (ret) + : "r" (1), "a" (p), "0" (*p) + : "cc", "memory" ); + return ret; +} +#elif defined(__alpha__) +static inline int testandset (int *p) +{ + int ret; + unsigned long one; + + __asm__ __volatile__ ("0: mov 1,%2\n" + " ldl_l %0,%1\n" + " stl_c %2,%1\n" + " beq %2,1f\n" + ".subsection 2\n" + "1: br 0b\n" + ".previous" + : "=r" (ret), "=m" (*p), "=r" (one) + : "m" (*p)); + return ret; +} +#elif defined(__sparc__) +static inline int testandset (int *p) +{ + int ret; + + __asm__ __volatile__("ldstub [%1], %0" + : "=r" (ret) + : "r" (p) + : "memory"); + + return (ret ? 1 : 0); +} +#elif defined(__arm__) +static inline int testandset (int *spinlock) +{ + register unsigned int ret; + __asm__ __volatile__("swp %0, %1, [%2]" + : "=r"(ret) + : "0"(1), "r"(spinlock)); + + return ret; +} +#elif defined(__mc68000) +static inline int testandset (int *p) +{ + char ret; + __asm__ __volatile__("tas %1; sne %0" + : "=r" (ret) + : "m" (p) + : "cc","memory"); + return ret; +} +#elif defined(__hppa__) + +/* Because malloc only guarantees 8-byte alignment for malloc'd data, + and GCC only guarantees 8-byte alignment for stack locals, we can't + be assured of 16-byte alignment for atomic lock data even if we + specify "__attribute ((aligned(16)))" in the type declaration. So, + we use a struct containing an array of four ints for the atomic lock + type and dynamically select the 16-byte aligned int from the array + for the semaphore. */ +#define __PA_LDCW_ALIGNMENT 16 +static inline void *ldcw_align (void *p) { + unsigned long a = (unsigned long)p; + a = (a + __PA_LDCW_ALIGNMENT - 1) & ~(__PA_LDCW_ALIGNMENT - 1); + return (void *)a; +} + +static inline int testandset (spinlock_t *p) +{ + unsigned int ret; + p = ldcw_align(p); + __asm__ __volatile__("ldcw 0(%1),%0" + : "=r" (ret) + : "r" (p) + : "memory" ); + return !ret; +} + +#elif defined(__ia64) + +#include <ia64intrin.h> + +static inline int testandset (int *p) +{ + return __sync_lock_test_and_set (p, 1); +} +#elif defined(__mips__) +static inline int testandset (int *p) +{ + int ret; + + __asm__ __volatile__ ( + " .set push \n" + " .set noat \n" + " .set mips2 \n" + "1: li $1, 1 \n" + " ll %0, %1 \n" + " sc $1, %1 \n" + " beqz $1, 1b \n" + " .set pop " + : "=r" (ret), "+R" (*p) + : + : "memory"); + + return ret; +} +#else +#error unimplemented CPU support +#endif + +#if defined(CONFIG_USER_ONLY) +static inline void spin_lock(spinlock_t *lock) +{ + while (testandset(lock)); +} + +static inline void spin_unlock(spinlock_t *lock) +{ + resetlock(lock); +} + +static inline int spin_trylock(spinlock_t *lock) +{ + return !testandset(lock); +} +#else +static inline void spin_lock(spinlock_t *lock) +{ +} + +static inline void spin_unlock(spinlock_t *lock) +{ +} + +static inline int spin_trylock(spinlock_t *lock) +{ + return 1; +} +#endif + +#endif |