.. | .. |
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12 | 12 | #define _XTENSA_SPINLOCK_H |
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13 | 13 | |
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14 | 14 | #include <asm/barrier.h> |
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15 | | -#include <asm/processor.h> |
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| 15 | +#include <asm/qrwlock.h> |
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| 16 | +#include <asm/qspinlock.h> |
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16 | 17 | |
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17 | | -/* |
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18 | | - * spinlock |
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19 | | - * |
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20 | | - * There is at most one owner of a spinlock. There are not different |
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21 | | - * types of spinlock owners like there are for rwlocks (see below). |
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22 | | - * |
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23 | | - * When trying to obtain a spinlock, the function "spins" forever, or busy- |
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24 | | - * waits, until the lock is obtained. When spinning, presumably some other |
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25 | | - * owner will soon give up the spinlock making it available to others. Use |
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26 | | - * the trylock functions to avoid spinning forever. |
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27 | | - * |
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28 | | - * possible values: |
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29 | | - * |
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30 | | - * 0 nobody owns the spinlock |
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31 | | - * 1 somebody owns the spinlock |
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32 | | - */ |
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33 | | - |
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34 | | -#define arch_spin_is_locked(x) ((x)->slock != 0) |
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35 | | - |
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36 | | -static inline void arch_spin_lock(arch_spinlock_t *lock) |
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37 | | -{ |
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38 | | - unsigned long tmp; |
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39 | | - |
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40 | | - __asm__ __volatile__( |
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41 | | - " movi %0, 0\n" |
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42 | | - " wsr %0, scompare1\n" |
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43 | | - "1: movi %0, 1\n" |
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44 | | - " s32c1i %0, %1, 0\n" |
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45 | | - " bnez %0, 1b\n" |
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46 | | - : "=&a" (tmp) |
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47 | | - : "a" (&lock->slock) |
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48 | | - : "memory"); |
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49 | | -} |
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50 | | - |
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51 | | -/* Returns 1 if the lock is obtained, 0 otherwise. */ |
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52 | | - |
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53 | | -static inline int arch_spin_trylock(arch_spinlock_t *lock) |
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54 | | -{ |
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55 | | - unsigned long tmp; |
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56 | | - |
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57 | | - __asm__ __volatile__( |
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58 | | - " movi %0, 0\n" |
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59 | | - " wsr %0, scompare1\n" |
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60 | | - " movi %0, 1\n" |
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61 | | - " s32c1i %0, %1, 0\n" |
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62 | | - : "=&a" (tmp) |
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63 | | - : "a" (&lock->slock) |
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64 | | - : "memory"); |
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65 | | - |
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66 | | - return tmp == 0 ? 1 : 0; |
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67 | | -} |
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68 | | - |
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69 | | -static inline void arch_spin_unlock(arch_spinlock_t *lock) |
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70 | | -{ |
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71 | | - unsigned long tmp; |
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72 | | - |
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73 | | - __asm__ __volatile__( |
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74 | | - " movi %0, 0\n" |
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75 | | - " s32ri %0, %1, 0\n" |
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76 | | - : "=&a" (tmp) |
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77 | | - : "a" (&lock->slock) |
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78 | | - : "memory"); |
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79 | | -} |
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80 | | - |
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81 | | -/* |
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82 | | - * rwlock |
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83 | | - * |
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84 | | - * Read-write locks are really a more flexible spinlock. They allow |
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85 | | - * multiple readers but only one writer. Write ownership is exclusive |
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86 | | - * (i.e., all other readers and writers are blocked from ownership while |
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87 | | - * there is a write owner). These rwlocks are unfair to writers. Writers |
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88 | | - * can be starved for an indefinite time by readers. |
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89 | | - * |
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90 | | - * possible values: |
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91 | | - * |
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92 | | - * 0 nobody owns the rwlock |
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93 | | - * >0 one or more readers own the rwlock |
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94 | | - * (the positive value is the actual number of readers) |
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95 | | - * 0x80000000 one writer owns the rwlock, no other writers, no readers |
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96 | | - */ |
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97 | | - |
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98 | | -static inline void arch_write_lock(arch_rwlock_t *rw) |
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99 | | -{ |
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100 | | - unsigned long tmp; |
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101 | | - |
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102 | | - __asm__ __volatile__( |
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103 | | - " movi %0, 0\n" |
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104 | | - " wsr %0, scompare1\n" |
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105 | | - "1: movi %0, 1\n" |
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106 | | - " slli %0, %0, 31\n" |
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107 | | - " s32c1i %0, %1, 0\n" |
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108 | | - " bnez %0, 1b\n" |
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109 | | - : "=&a" (tmp) |
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110 | | - : "a" (&rw->lock) |
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111 | | - : "memory"); |
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112 | | -} |
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113 | | - |
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114 | | -/* Returns 1 if the lock is obtained, 0 otherwise. */ |
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115 | | - |
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116 | | -static inline int arch_write_trylock(arch_rwlock_t *rw) |
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117 | | -{ |
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118 | | - unsigned long tmp; |
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119 | | - |
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120 | | - __asm__ __volatile__( |
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121 | | - " movi %0, 0\n" |
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122 | | - " wsr %0, scompare1\n" |
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123 | | - " movi %0, 1\n" |
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124 | | - " slli %0, %0, 31\n" |
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125 | | - " s32c1i %0, %1, 0\n" |
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126 | | - : "=&a" (tmp) |
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127 | | - : "a" (&rw->lock) |
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128 | | - : "memory"); |
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129 | | - |
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130 | | - return tmp == 0 ? 1 : 0; |
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131 | | -} |
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132 | | - |
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133 | | -static inline void arch_write_unlock(arch_rwlock_t *rw) |
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134 | | -{ |
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135 | | - unsigned long tmp; |
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136 | | - |
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137 | | - __asm__ __volatile__( |
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138 | | - " movi %0, 0\n" |
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139 | | - " s32ri %0, %1, 0\n" |
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140 | | - : "=&a" (tmp) |
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141 | | - : "a" (&rw->lock) |
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142 | | - : "memory"); |
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143 | | -} |
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144 | | - |
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145 | | -static inline void arch_read_lock(arch_rwlock_t *rw) |
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146 | | -{ |
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147 | | - unsigned long tmp; |
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148 | | - unsigned long result; |
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149 | | - |
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150 | | - __asm__ __volatile__( |
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151 | | - "1: l32i %1, %2, 0\n" |
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152 | | - " bltz %1, 1b\n" |
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153 | | - " wsr %1, scompare1\n" |
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154 | | - " addi %0, %1, 1\n" |
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155 | | - " s32c1i %0, %2, 0\n" |
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156 | | - " bne %0, %1, 1b\n" |
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157 | | - : "=&a" (result), "=&a" (tmp) |
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158 | | - : "a" (&rw->lock) |
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159 | | - : "memory"); |
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160 | | -} |
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161 | | - |
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162 | | -/* Returns 1 if the lock is obtained, 0 otherwise. */ |
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163 | | - |
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164 | | -static inline int arch_read_trylock(arch_rwlock_t *rw) |
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165 | | -{ |
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166 | | - unsigned long result; |
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167 | | - unsigned long tmp; |
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168 | | - |
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169 | | - __asm__ __volatile__( |
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170 | | - " l32i %1, %2, 0\n" |
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171 | | - " addi %0, %1, 1\n" |
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172 | | - " bltz %0, 1f\n" |
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173 | | - " wsr %1, scompare1\n" |
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174 | | - " s32c1i %0, %2, 0\n" |
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175 | | - " sub %0, %0, %1\n" |
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176 | | - "1:\n" |
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177 | | - : "=&a" (result), "=&a" (tmp) |
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178 | | - : "a" (&rw->lock) |
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179 | | - : "memory"); |
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180 | | - |
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181 | | - return result == 0; |
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182 | | -} |
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183 | | - |
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184 | | -static inline void arch_read_unlock(arch_rwlock_t *rw) |
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185 | | -{ |
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186 | | - unsigned long tmp1, tmp2; |
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187 | | - |
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188 | | - __asm__ __volatile__( |
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189 | | - "1: l32i %1, %2, 0\n" |
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190 | | - " addi %0, %1, -1\n" |
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191 | | - " wsr %1, scompare1\n" |
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192 | | - " s32c1i %0, %2, 0\n" |
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193 | | - " bne %0, %1, 1b\n" |
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194 | | - : "=&a" (tmp1), "=&a" (tmp2) |
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195 | | - : "a" (&rw->lock) |
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196 | | - : "memory"); |
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197 | | -} |
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| 18 | +#define smp_mb__after_spinlock() smp_mb() |
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198 | 19 | |
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199 | 20 | #endif /* _XTENSA_SPINLOCK_H */ |
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