nginx 0.6.22 *) Change: now all ngx_http_perl_module methods return values copied to perl's allocated memory. *) Bugfix: if nginx was built with ngx_http_perl_module, the perl before 5.8.6 was used, and perl supported threads, then during reconfiguration the master process aborted; bug appeared in 0.5.9. Thanks to Boris Zhmurov. *) Bugfix: the ngx_http_perl_module methods may get invalid values of the regex captures. *) Bugfix: a segmentation fault occurred in worker process, if the $r->has_request_body() method was called for a request whose small request body was already received. *) Bugfix: large_client_header_buffers did not freed before going to keep-alive state. Thanks to Olexander Shtepa. *) Bugfix: the last address was missed in the $upstream_addr variable; bug appeared in 0.6.18. *) Bugfix: the "fastcgi_catch_stderr" directive did return error code; now it returns 502 code, that can be rerouted to a next server using the "fastcgi_next_upstream invalid_header" directive. *) Bugfix: a segmentation fault occurred in master process if the "fastcgi_catch_stderr" directive was used; bug appeared in 0.6.10. Thanks to Manlio Perillo.

/*
 * 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

}