Mercurial > hg > nginx-quic
annotate src/os/unix/ngx_gcc_atomic_sparc64.h @ 6428:545b5e4d83b2
Upstream: avoid closing client connection in edge case.
If proxy_cache is enabled, and proxy_no_cache tests true, it was previously
possible for the client connection to be closed after a 304. The fix is to
recheck r->header_only after the final cacheability is determined, and end the
request if no longer cacheable.
Example configuration:
proxy_cache foo;
proxy_cache_bypass 1;
proxy_no_cache 1;
If a client sends If-None-Match, and the upstream server returns 200 with a
matching ETag, no body should be returned to the client. At the start of
ngx_http_upstream_send_response proxy_no_cache is not yet tested, thus cacheable
is still 1 and downstream_error is set.
However, by the time the downstream_error check is done in process_request,
proxy_no_cache has been tested and cacheable is set to 0. The client connection
is then closed, regardless of keepalive.
author | Justin Li <jli.justinli@gmail.com> |
---|---|
date | Tue, 08 Mar 2016 22:31:55 -0500 |
parents | 67653855682e |
children |
rev | line source |
---|---|
561 | 1 |
2 /* | |
3 * Copyright (C) Igor Sysoev | |
4412 | 4 * Copyright (C) Nginx, Inc. |
561 | 5 */ |
6 | |
7 | |
8 /* | |
9 * "casa [r1] 0x80, r2, r0" and | |
10 * "casxa [r1] 0x80, r2, r0" do the following: | |
11 * | |
12 * if ([r1] == r2) { | |
13 * swap(r0, [r1]); | |
14 * } else { | |
15 * r0 = [r1]; | |
16 * } | |
17 * | |
4572
67653855682e
Fixed spelling in multiline C comments.
Ruslan Ermilov <ru@nginx.com>
parents:
4412
diff
changeset
|
18 * so "r0 == r2" means that the operation was successful. |
561 | 19 * |
20 * | |
21 * The "r" means the general register. | |
22 * The "+r" means the general register used for both input and output. | |
23 */ | |
24 | |
25 | |
26 #if (NGX_PTR_SIZE == 4) | |
27 #define NGX_CASA "casa" | |
28 #else | |
29 #define NGX_CASA "casxa" | |
30 #endif | |
31 | |
32 | |
33 static ngx_inline ngx_atomic_uint_t | |
34 ngx_atomic_cmp_set(ngx_atomic_t *lock, ngx_atomic_uint_t old, | |
35 ngx_atomic_uint_t set) | |
36 { | |
37 __asm__ volatile ( | |
38 | |
39 NGX_CASA " [%1] 0x80, %2, %0" | |
40 | |
41 : "+r" (set) : "r" (lock), "r" (old) : "memory"); | |
42 | |
43 return (set == old); | |
577 | 44 } |
561 | 45 |
46 | |
47 static ngx_inline ngx_atomic_int_t | |
48 ngx_atomic_fetch_add(ngx_atomic_t *value, ngx_atomic_int_t add) | |
49 { | |
50 ngx_atomic_uint_t old, res; | |
51 | |
52 old = *value; | |
53 | |
54 for ( ;; ) { | |
55 | |
56 res = old + add; | |
57 | |
58 __asm__ volatile ( | |
59 | |
60 NGX_CASA " [%1] 0x80, %2, %0" | |
61 | |
62 : "+r" (res) : "r" (value), "r" (old) : "memory"); | |
63 | |
64 if (res == old) { | |
65 return res; | |
66 } | |
67 | |
68 old = res; | |
69 } | |
70 } | |
563 | 71 |
72 | |
73 #if (NGX_SMP) | |
74 #define ngx_memory_barrier() \ | |
75 __asm__ volatile ( \ | |
76 "membar #LoadLoad | #LoadStore | #StoreStore | #StoreLoad" \ | |
77 ::: "memory") | |
78 #else | |
79 #define ngx_memory_barrier() __asm__ volatile ("" ::: "memory") | |
80 #endif | |
611 | 81 |
82 #define ngx_cpu_pause() |