29 lines
495 B
C++
29 lines
495 B
C++
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#include <fb.h>
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#include <lock.h>
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#include <stdint.h>
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#include <tool.h>
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namespace lock {
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int swap(lock_t *lock) {
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return __sync_bool_compare_and_swap(&lock->lock, 0, 1);
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}
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void acquire(lock_t *lock) {
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uint64_t count = 0;
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for (;;) {
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if (swap(lock)) { break; }
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count++;
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if (count > 1000000) {
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fb::printf("%s deadlock", lock->file);
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assert(0);
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}
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asm volatile("pause");
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}
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}
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void release(lock_t *lock) {
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__sync_bool_compare_and_swap(&lock->lock, 1, 0);
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}
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} // namespace lock
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