blob: dfa7da4112086b367f87c921626d15bae21d629b [file] [log] [blame] [raw]
/*
* Copyright (C) Igor Sysoev
*/
#include <ngx_config.h>
#include <ngx_core.h>
void ngx_spinlock(ngx_atomic_t *lock, ngx_uint_t spin)
{
#if (NGX_HAVE_ATOMIC_OPS)
ngx_uint_t tries;
tries = 0;
for ( ;; ) {
if (*lock) {
if (ngx_ncpu > 1 && tries++ < spin) {
continue;
}
ngx_sched_yield();
tries = 0;
} else {
if (ngx_atomic_cmp_set(lock, 0, 1)) {
return;
}
}
}
#else
#if (NGX_THREADS)
#error ngx_spinlock() or ngx_atomic_cmp_set() are not defined !
#endif
#endif
}