Mercurial > hg > nginx-vendor-1-0
annotate src/core/ngx_spinlock.c @ 196:8759b346e431 NGINX_0_3_45
nginx 0.3.45
*) Feature: the "ssl_verify_client", "ssl_verify_depth", and
"ssl_client_certificate" directives.
*) Change: the $request_method variable now returns the main request
method.
*) Change: the ° symbol codes were changed in koi-win conversion
table.
*) Feature: the euro и N symbols were added to koi-win conversion table.
*) Bugfix: if nginx distributed the requests among several backends and
some backend failed, then requests intended for this backend was
directed to one live backend only instead of being distributed among
the rest.
| author | Igor Sysoev <http://sysoev.ru> |
|---|---|
| date | Sat, 06 May 2006 00:00:00 +0400 |
| parents | 73e8476f9142 |
| children | ad25218fd14b |
| rev | line source |
|---|---|
| 0 | 1 |
| 2 /* | |
| 3 * Copyright (C) Igor Sysoev | |
| 4 */ | |
| 5 | |
| 6 | |
| 7 #include <ngx_config.h> | |
| 8 #include <ngx_core.h> | |
| 9 | |
| 10 | |
| 112 | 11 void |
| 160 | 12 ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin) |
| 0 | 13 { |
| 14 | |
| 15 #if (NGX_HAVE_ATOMIC_OPS) | |
| 16 | |
| 160 | 17 ngx_uint_t i, n; |
| 0 | 18 |
| 19 for ( ;; ) { | |
| 20 | |
| 160 | 21 if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) { |
| 22 return; | |
| 23 } | |
| 24 | |
| 25 if (ngx_ncpu > 1) { | |
| 26 | |
| 27 for (n = 1; n < spin; n <<= 1) { | |
| 0 | 28 |
| 160 | 29 for (i = 0; i < n; i++) { |
| 30 ngx_cpu_pause(); | |
| 31 } | |
| 0 | 32 |
| 160 | 33 if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) { |
| 34 return; | |
| 35 } | |
| 0 | 36 } |
| 37 } | |
| 160 | 38 |
| 39 ngx_sched_yield(); | |
| 0 | 40 } |
| 41 | |
| 42 #else | |
| 43 | |
| 44 #if (NGX_THREADS) | |
| 45 | |
| 46 #error ngx_spinlock() or ngx_atomic_cmp_set() are not defined ! | |
| 47 | |
| 48 #endif | |
| 49 | |
| 50 #endif | |
| 51 | |
| 52 } |