| The Android Open Source Project | 1dc9e47 | 2009-03-03 19:28:35 -0800 | [diff] [blame] | 1 | #include <sys/linux-syscalls.h> |
| 2 | |
| 3 | #define FUTEX_WAIT 0 |
| 4 | #define FUTEX_WAKE 1 |
| 5 | |
| 6 | |
| 7 | /* |
| 8 | * int __futex_wait(volatile void *ftx, int val, const struct timespec *timeout) |
| 9 | */ |
| 10 | .text |
| 11 | .globl __futex_wait |
| 12 | .type __futex_wait, @function |
| 13 | .align 4 |
| 14 | __futex_wait: |
| 15 | pushl %ebx |
| 16 | pushl %esi |
| 17 | mov 12(%esp), %ebx /* ftx */ |
| 18 | movl $FUTEX_WAIT, %ecx |
| 19 | mov 16(%esp), %edx /* val */ |
| 20 | mov 20(%esp), %esi /* timeout */ |
| 21 | movl $__NR_futex, %eax |
| 22 | int $0x80 |
| 23 | popl %esi |
| 24 | popl %ebx |
| 25 | ret |
| 26 | |
| 27 | |
| 28 | /* int __futex_wake(volatile void *ftx, int count) */ |
| 29 | |
| 30 | .text |
| 31 | .globl __futex_wake |
| 32 | .type __futex_wake, @function |
| 33 | .align 4 |
| 34 | __futex_wake: |
| 35 | pushl %ebx |
| 36 | mov 8(%esp), %ebx /* ftx */ |
| 37 | movl $FUTEX_WAKE, %ecx |
| 38 | mov 12(%esp), %edx /* count */ |
| 39 | movl $__NR_futex, %eax |
| 40 | int $0x80 |
| 41 | popl %ebx |
| 42 | ret |
| 43 | |
| 44 | |
| 45 | /* int __atomic_cmpxchg(int old, int new, volatile int* addr) */ |
| 46 | |
| 47 | .text |
| 48 | .globl __atomic_cmpxchg |
| 49 | .type __atomic_cmpxchg, @function |
| 50 | .align 4 |
| 51 | __atomic_cmpxchg: |
| 52 | mov 4(%esp), %eax /* old */ |
| 53 | mov 8(%esp), %ecx /* new */ |
| 54 | mov 12(%esp), %edx /* addr */ |
| 55 | lock cmpxchg %ecx, (%edx) |
| 56 | jnz 1f |
| 57 | xor %eax, %eax |
| 58 | jmp 2f |
| 59 | 1: |
| 60 | movl $1, %eax |
| 61 | 2: |
| 62 | ret /* 0 == success, 1 == failure */ |
| 63 | |
| 64 | |
| 65 | /* int __atomic_swap(int new, volatile int* addr) */ |
| 66 | |
| 67 | .text |
| 68 | .globl __atomic_swap |
| 69 | .type __atomic_swap, @function |
| 70 | .align 4 |
| 71 | __atomic_swap: |
| 72 | mov 4(%esp), %ecx /* new */ |
| 73 | mov 8(%esp), %edx /* addr */ |
| 74 | lock xchg %ecx, (%edx) |
| 75 | mov %ecx, %eax |
| 76 | ret |
| 77 | |
| 78 | |
| 79 | /* |
| 80 | * int __atomic_dec(volatile int* addr) |
| 81 | * |
| 82 | * My x86 asm is really rusty.. this is probably suboptimal |
| 83 | */ |
| 84 | |
| 85 | .text |
| 86 | .globl __atomic_dec |
| 87 | .type __atomic_dec, @function |
| 88 | .align 4 |
| 89 | __atomic_dec: |
| 90 | pushl %ebx |
| 91 | pushl %esi |
| 92 | movl 12(%esp), %ebx /* addr */ |
| 93 | |
| 94 | 1: |
| 95 | movl (%ebx), %esi /* old = *addr */ |
| 96 | movl %esi, %edx |
| 97 | subl $1, %edx /* new = old - 1 */ |
| 98 | |
| 99 | pushl %ebx |
| 100 | pushl %edx |
| 101 | pushl %esi |
| 102 | call __atomic_cmpxchg |
| 103 | addl $12, %esp |
| 104 | test %eax, %eax |
| 105 | jnz 1b |
| 106 | |
| 107 | movl %esi, %eax /* return old */ |
| 108 | popl %esi |
| 109 | popl %ebx |
| 110 | ret |
| 111 | |
| 112 | |
| 113 | .text |
| 114 | /* int __atomic_inc(volatile int* addr) */ |
| 115 | .globl __atomic_inc |
| 116 | .type __atomic_inc, @function |
| 117 | .align 4 |
| 118 | __atomic_inc: |
| 119 | pushl %ebx |
| 120 | pushl %esi |
| 121 | movl 12(%esp), %ebx /* addr */ |
| 122 | |
| 123 | 1: |
| 124 | movl (%ebx), %esi /* old = *addr */ |
| 125 | movl %esi, %edx |
| 126 | addl $1, %edx /* new = old + 1 */ |
| 127 | |
| 128 | pushl %ebx |
| 129 | pushl %edx |
| 130 | pushl %esi |
| 131 | call __atomic_cmpxchg |
| 132 | addl $12, %esp |
| 133 | test %eax, %eax |
| 134 | jnz 1b |
| 135 | |
| 136 | movl %esi, %eax /* return old */ |
| 137 | popl %esi |
| 138 | popl %ebx |
| 139 | ret |
| 140 | |