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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
|
/*
* Copyright (c) 2013 Red Hat.
* Copyright (c) 2011 Ken McDonell. All Rights Reserved.
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*/
#include "pmapi.h"
#include "impl.h"
#include "internal.h"
#ifdef HAVE_EXECINFO_H
#include <execinfo.h>
#endif
#ifdef PM_MULTI_THREAD
typedef struct {
void *lock;
int count;
} lockdbg_t;
#define PM_LOCK_OP 1
#define PM_UNLOCK_OP 2
static int multi_init[PM_SCOPE_MAX+1];
static pthread_t multi_seen[PM_SCOPE_MAX+1];
/* the big libpcp lock */
#ifdef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
pthread_mutex_t __pmLock_libpcp = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
#else
pthread_mutex_t __pmLock_libpcp = PTHREAD_MUTEX_INITIALIZER;
#ifndef HAVE___THREAD
pthread_key_t __pmTPDKey = 0;
static void
__pmTPD__destroy(void *addr)
{
free(addr);
}
#endif
#endif
void
__pmInitLocks(void)
{
static pthread_mutex_t init = PTHREAD_MUTEX_INITIALIZER;
static int done = 0;
int psts;
char errmsg[PM_MAXERRMSGLEN];
if ((psts = pthread_mutex_lock(&init)) != 0) {
pmErrStr_r(-psts, errmsg, sizeof(errmsg));
fprintf(stderr, "__pmInitLocks: pthread_mutex_lock failed: %s", errmsg);
exit(4);
}
if (!done) {
#ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
/*
* Unable to initialize at compile time, need to do it here in
* a one trip for all threads run-time initialization.
*/
pthread_mutexattr_t attr;
if ((psts = pthread_mutexattr_init(&attr)) != 0) {
pmErrStr_r(-psts, errmsg, sizeof(errmsg));
fprintf(stderr, "__pmInitLocks: pthread_mutexattr_init failed: %s", errmsg);
exit(4);
}
if ((psts = pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) != 0) {
pmErrStr_r(-psts, errmsg, sizeof(errmsg));
fprintf(stderr, "__pmInitLocks: pthread_mutexattr_settype failed: %s", errmsg);
exit(4);
}
if ((psts = pthread_mutex_init(&__pmLock_libpcp, &attr)) != 0) {
pmErrStr_r(-psts, errmsg, sizeof(errmsg));
fprintf(stderr, "__pmInitLocks: pthread_mutex_init failed: %s", errmsg);
exit(4);
}
#endif
#ifndef HAVE___THREAD
/* first thread here creates the thread private data key */
if ((psts = pthread_key_create(&__pmTPDKey, __pmTPD__destroy)) != 0) {
pmErrStr_r(-psts, errmsg, sizeof(errmsg));
fprintf(stderr, "__pmInitLocks: pthread_key_create failed: %s", errmsg);
exit(4);
}
#endif
done = 1;
}
if ((psts = pthread_mutex_unlock(&init)) != 0) {
pmErrStr_r(-psts, errmsg, sizeof(errmsg));
fprintf(stderr, "__pmInitLocks: pthread_mutex_unlock failed: %s", errmsg);
exit(4);
}
#ifndef HAVE___THREAD
if (pthread_getspecific(__pmTPDKey) == NULL) {
__pmTPD *tpd = (__pmTPD *)malloc(sizeof(__pmTPD));
if (tpd == NULL) {
__pmNoMem("__pmInitLocks: __pmTPD", sizeof(__pmTPD), PM_FATAL_ERR);
/*NOTREACHED*/
}
if ((psts = pthread_setspecific(__pmTPDKey, tpd)) != 0) {
pmErrStr_r(-psts, errmsg, sizeof(errmsg));
fprintf(stderr, "__pmInitLocks: pthread_setspecific failed: %s", errmsg);
exit(4);
}
tpd->curcontext = PM_CONTEXT_UNDEF;
}
#endif
}
int
__pmMultiThreaded(int scope)
{
int sts = 0;
PM_INIT_LOCKS();
PM_LOCK(__pmLock_libpcp);
if (!multi_init[scope]) {
multi_init[scope] = 1;
multi_seen[scope] = pthread_self();
}
else {
if (!pthread_equal(multi_seen[scope], pthread_self()))
sts = 1;
}
PM_UNLOCK(__pmLock_libpcp);
return sts;
}
#ifdef PM_MULTI_THREAD_DEBUG
void
__pmDebugLock(int op, void *lock, const char *file, int line)
{
int report = 0;
int ctx;
static __pmHashCtl hashctl = { 0, 0, NULL };
__pmHashNode *hp = NULL;
lockdbg_t *ldp;
int try;
int sts;
if (lock == (void *)&__pmLock_libpcp) {
if ((pmDebug & DBG_TRACE_APPL0) | ((pmDebug & (DBG_TRACE_APPL0 | DBG_TRACE_APPL1 | DBG_TRACE_APPL2)) == 0))
report = DBG_TRACE_APPL0;
}
else if ((ctx = __pmIsContextLock(lock)) >= 0) {
if ((pmDebug & DBG_TRACE_APPL1) | ((pmDebug & (DBG_TRACE_APPL0 | DBG_TRACE_APPL1 | DBG_TRACE_APPL2)) == 0))
report = DBG_TRACE_APPL1;
}
else {
if ((pmDebug & DBG_TRACE_APPL2) | ((pmDebug & (DBG_TRACE_APPL0 | DBG_TRACE_APPL1 | DBG_TRACE_APPL2)) == 0))
report = DBG_TRACE_APPL2;
}
if (report) {
__psint_t key = (__psint_t)lock;
fprintf(stderr, "%s:%d %s", file, line, op == PM_LOCK_OP ? "lock" : "unlock");
try = 0;
again:
hp = __pmHashSearch((unsigned int)key, &hashctl);
while (hp != NULL) {
ldp = (lockdbg_t *)hp->data;
if (ldp->lock == lock)
break;
hp = hp->next;
}
if (hp == NULL) {
char errmsg[PM_MAXERRMSGLEN];
ldp = (lockdbg_t *)malloc(sizeof(lockdbg_t));
ldp->lock = lock;
ldp->count = 0;
sts = __pmHashAdd((unsigned int)key, (void *)ldp, &hashctl);
if (sts == 1) {
try++;
if (try == 1)
goto again;
}
hp = NULL;
fprintf(stderr, " hash control failure: %s\n", pmErrStr_r(-sts, errmsg, sizeof(errmsg)));
}
}
if (report == DBG_TRACE_APPL0) {
fprintf(stderr, "(global_libpcp)");
}
else if (report == DBG_TRACE_APPL1) {
fprintf(stderr, "(ctx %d)", ctx);
}
else if (report == DBG_TRACE_APPL2) {
if ((ctx = __pmIsChannelLock(lock)) >= 0)
fprintf(stderr, "(ctx %d ipc channel)", ctx);
else if (__pmIsDeriveLock(lock))
fprintf(stderr, "(derived_metric)");
else
fprintf(stderr, "(" PRINTF_P_PFX "%p)", lock);
}
if (report) {
if (hp != NULL) {
ldp = (lockdbg_t *)hp->data;
if (op == PM_LOCK_OP) {
if (ldp->count != 0)
fprintf(stderr, " [count=%d]", ldp->count);
ldp->count++;
}
else {
if (ldp->count != 1)
fprintf(stderr, " [count=%d]", ldp->count);
ldp->count--;
}
}
fputc('\n', stderr);
#ifdef HAVE_BACKTRACE
#define MAX_TRACE_DEPTH 32
{
void *backaddr[MAX_TRACE_DEPTH];
sts = backtrace(backaddr, MAX_TRACE_DEPTH);
if (sts > 0) {
char **symbols;
symbols = backtrace_symbols(backaddr, MAX_TRACE_DEPTH);
if (symbols != NULL) {
int i;
fprintf(stderr, "backtrace:\n");
for (i = 0; i < sts; i++)
fprintf(stderr, " %s\n", symbols[i]);
free(symbols);
}
}
}
#endif
}
}
#else
#define __pmDebugLock(op, lock, file, line) do { } while (0)
#endif
int
__pmLock(void *lock, const char *file, int line)
{
int sts;
if (pmDebug & DBG_TRACE_LOCK)
__pmDebugLock(PM_LOCK_OP, lock, file, line);
if ((sts = pthread_mutex_lock(lock)) != 0) {
sts = -sts;
if (pmDebug & DBG_TRACE_DESPERATE)
fprintf(stderr, "%s:%d: lock failed: %s\n", file, line, pmErrStr(sts));
}
return sts;
}
int
__pmUnlock(void *lock, const char *file, int line)
{
int sts;
if (pmDebug & DBG_TRACE_LOCK)
__pmDebugLock(PM_UNLOCK_OP, lock, file, line);
if ((sts = pthread_mutex_unlock(lock)) != 0) {
sts = -sts;
if (pmDebug & DBG_TRACE_DESPERATE)
fprintf(stderr, "%s:%d: unlock failed: %s\n", file, line, pmErrStr(sts));
}
return sts;
}
#else /* !PM_MULTI_THREAD - symbols exposed at the shlib ABI level */
void *__pmLock_libpcp;
void __pmInitLocks(void) { }
int __pmMultiThreaded(int scope) { (void)scope; return 0; }
int __pmLock(void *l, const char *f, int n) { (void)l, (void)f, (void)n; return 0; }
int __pmUnlock(void *l, const char *f, int n) { (void)l, (void)f, (void)n; return 0; }
#endif
|
