mirror of
https://github.com/fluencelabs/musl
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23 lines
428 B
C
23 lines
428 B
C
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#include "pthread_impl.h"
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static int vmlock[2];
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void __vm_lock(int inc)
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{
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for (;;) {
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int v = vmlock[0];
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if (inc*v < 0) __wait(vmlock, vmlock+1, v, 1);
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else if (a_cas(vmlock, v, v+inc)==v) break;
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}
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}
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void __vm_unlock(void)
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{
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int inc = vmlock[0]>0 ? -1 : 1;
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if (a_fetch_add(vmlock, inc)==-inc && vmlock[1])
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__wake(vmlock, -1, 1);
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}
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weak_alias(__vm_lock, __vm_lock_impl);
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weak_alias(__vm_unlock, __vm_unlock_impl);
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