nginx-0.3.36-RELEASE import *) Feature: the ngx_http_addition_filter_module. *) Feature: the "proxy_pass" and "fastcgi_pass" directives may be used inside the "if" block. *) Feature: the "proxy_ignore_client_abort" and "fastcgi_ignore_client_abort" directives. *) Feature: the "$request_completion" variable. *) Feature: the ngx_http_perl_module supports the $r->request_method and $r->remote_addr. *) Feature: the ngx_http_ssi_module supports the "elif" command. *) Bugfix: the "\/" string in the expression of the "if" command of the ngx_http_ssi_module was treated incorrectly. *) Bugfix: in the regular expressions in the "if" command of the ngx_http_ssi_module. *) Bugfix: if the relative path was specified in the "client_body_temp_path", "proxy_temp_path", "fastcgi_temp_path", and "perl_modules" directives, then the directory was used relatively to a current path but not to a server prefix.

/*
 * Copyright (C) Igor Sysoev
 */


#include <ngx_config.h>
#include <ngx_core.h>


void
ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin)
{

#if (NGX_HAVE_ATOMIC_OPS)

    ngx_uint_t  i, n;

    for ( ;; ) {

        if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) {
            return;
        }

        if (ngx_ncpu > 1) {

            for (n = 1; n < spin; n <<= 1) {

                for (i = 0; i < n; i++) {
                    ngx_cpu_pause();
                }

                if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) {
                    return;
                }
            }
        }

        ngx_sched_yield();
    }

#else

#if (NGX_THREADS)

#error ngx_spinlock() or ngx_atomic_cmp_set() are not defined !

#endif

#endif

}