1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
|
/*******************************************************************************
* Copyright (c) 2009, 2011 Wind River Systems, Inc. and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* and Eclipse Distribution License v1.0 which accompany this distribution.
* The Eclipse Public License is available at
* http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
* You may elect to redistribute this code under either of these licenses.
*
* Contributors:
* Wind River Systems - initial API and implementation
*******************************************************************************/
/*
* Abstract asynchronous data cache support.
*/
#include <tcf/config.h>
#include <assert.h>
#include <string.h>
#include <tcf/framework/errors.h>
#include <tcf/framework/exceptions.h>
#include <tcf/framework/myalloc.h>
#include <tcf/framework/events.h>
#include <tcf/framework/trace.h>
#include <tcf/framework/cache.h>
typedef struct WaitingCacheClient {
CacheClient * client;
Channel * channel;
void * args;
size_t args_size;
int args_copy;
#ifndef NDEBUG
const char * file;
int line;
#endif
} WaitingCacheClient;
static WaitingCacheClient current_client = {0, 0, 0, 0, 0};
static int client_exited = 0;
static int cache_miss_cnt = 0;
static WaitingCacheClient * wait_list_buf;
static unsigned wait_list_max;
static LINK cache_list = TCF_LIST_INIT(cache_list);
static void run_cache_client(void) {
Trap trap;
cache_miss_cnt = 0;
client_exited = 0;
if (set_trap(&trap)) {
current_client.client(current_client.args);
clear_trap(&trap);
assert(cache_miss_cnt == 0);
assert(client_exited);
}
else if (get_error_code(trap.error) != ERR_CACHE_MISS || client_exited || cache_miss_cnt == 0) {
trace(LOG_ALWAYS, "Unhandled exception in data cache client: %d %s", trap.error, errno_to_str(trap.error));
}
if (cache_miss_cnt == 0 && current_client.args_copy) loc_free(current_client.args);
memset(¤t_client, 0, sizeof(current_client));
cache_miss_cnt = 0;
client_exited = 0;
}
void cache_enter(CacheClient * client, Channel * channel, void * args, size_t args_size) {
assert(is_dispatch_thread());
assert(client != NULL);
assert(channel != NULL);
assert(!is_channel_closed(channel));
assert(current_client.client == NULL);
current_client.client = client;
current_client.channel = channel;
current_client.args = args;
current_client.args_size = args_size;
current_client.args_copy = 0;
run_cache_client();
}
void cache_exit(void) {
assert(is_dispatch_thread());
assert(current_client.client != NULL);
assert(!client_exited);
if (cache_miss_cnt > 0) exception(ERR_CACHE_MISS);
client_exited = 1;
}
#ifdef NDEBUG
void cache_wait(AbstractCache * cache) {
#else
void cache_wait_dbg(const char * file, int line, AbstractCache * cache) {
#endif
assert(is_dispatch_thread());
assert(client_exited == 0);
if (current_client.client != NULL && cache_miss_cnt == 0) {
if (cache->wait_list_cnt >= cache->wait_list_max) {
cache->wait_list_max += 8;
cache->wait_list_buf = (WaitingCacheClient *)loc_realloc(cache->wait_list_buf, cache->wait_list_max * sizeof(WaitingCacheClient));
}
if (current_client.args != NULL && !current_client.args_copy) {
void * mem = loc_alloc(current_client.args_size);
memcpy(mem, current_client.args, current_client.args_size);
current_client.args = mem;
current_client.args_copy = 1;
}
#ifndef NDEBUG
current_client.file = file;
current_client.line = line;
#endif
if (cache->wait_list_cnt == 0) list_add_last(&cache->link, &cache_list);
cache->wait_list_buf[cache->wait_list_cnt++] = current_client;
channel_lock(current_client.channel);
}
#ifndef NDEBUG
else if (current_client.client == NULL) {
trace(LOG_ALWAYS, "cache_wait(): illegal cache access at %s:%d", file, line);
}
#endif
cache_miss_cnt++;
exception(ERR_CACHE_MISS);
}
void cache_notify(AbstractCache * cache) {
unsigned i;
unsigned cnt = cache->wait_list_cnt;
assert(is_dispatch_thread());
if (cnt == 0) return;
list_remove(&cache->link);
cache->wait_list_cnt = 0;
if (wait_list_max < cnt) {
wait_list_max = cnt;
wait_list_buf = (WaitingCacheClient *)loc_realloc(wait_list_buf, cnt * sizeof(WaitingCacheClient));
}
memcpy(wait_list_buf, cache->wait_list_buf, cnt * sizeof(WaitingCacheClient));
for (i = 0; i < cnt; i++) {
current_client = wait_list_buf[i];
run_cache_client();
channel_unlock(wait_list_buf[i].channel);
}
}
Channel * cache_channel(void) {
return current_client.channel;
}
void cache_dispose(AbstractCache * cache) {
assert(is_dispatch_thread());
assert(cache->wait_list_cnt == 0);
assert(list_is_empty(&cache->link));
loc_free(cache->wait_list_buf);
memset(cache, 0, sizeof(*cache));
}
|
