Mercurial > hg > nginx-vendor-0-8
annotate src/core/ngx_spinlock.c @ 86:962c43960644 NGINX_0_1_43
nginx 0.1.43
*) Feature: the listen(2) backlog in the "listen" directive can be
changed using the -HUP signal.
*) Feature: the geo2nginx.pl script was added to contrib.
*) Change: the FastCGI parameters with the empty values now are passed
to a server.
*) Bugfix: the segmentation fault occurred or the worker process may
got caught in an endless loop if the proxied or FastCGI server sent
the "Cache-Control" header line and the "expires" directive was
used; in the proxied mode the bug appeared in 0.1.29.
author | Igor Sysoev <http://sysoev.ru> |
---|---|
date | Tue, 30 Aug 2005 00:00:00 +0400 |
parents | 41ccba1aba45 |
children | 408f195b3482 |
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 | |
42 | 11 /* |
12 * TODO: the P4 optimized assembler version with the "pause" operation | |
13 */ | |
14 | |
0 | 15 void ngx_spinlock(ngx_atomic_t *lock, ngx_uint_t spin) |
16 { | |
17 | |
18 #if (NGX_HAVE_ATOMIC_OPS) | |
19 | |
20 ngx_uint_t tries; | |
21 | |
22 tries = 0; | |
23 | |
24 for ( ;; ) { | |
25 | |
26 if (*lock) { | |
27 if (ngx_ncpu > 1 && tries++ < spin) { | |
28 continue; | |
29 } | |
30 | |
31 ngx_sched_yield(); | |
32 | |
33 tries = 0; | |
34 | |
35 } else { | |
36 if (ngx_atomic_cmp_set(lock, 0, 1)) { | |
37 return; | |
38 } | |
39 } | |
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 } |