summaryrefslogtreecommitdiff
path: root/lib/isc/pthreads/mutex.c
blob: 17cca53fc6a7286a20e9b6b8f89b1dfc0836b6cf (plain) (blame)
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
/*
 * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 2000-2003  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/* $Id: mutex.c,v 1.6.26.8 2007/08/28 07:19:17 tbox Exp $ */

#include <config.h>

#include <stdio.h>
#include <time.h>
#include <sys/time.h>

#include <isc/mutex.h>
#include <isc/util.h>

#if ISC_MUTEX_PROFILE

/* Operations on timevals; adapted from FreeBSD's sys/time.h */
#define timevalclear(tvp)      ((tvp)->tv_sec = (tvp)->tv_usec = 0)
#define timevaladd(vvp, uvp)                                            \
        do {                                                            \
                (vvp)->tv_sec += (uvp)->tv_sec;                         \
                (vvp)->tv_usec += (uvp)->tv_usec;                       \
                if ((vvp)->tv_usec >= 1000000) {                        \
                        (vvp)->tv_sec++;                                \
                        (vvp)->tv_usec -= 1000000;                      \
                }                                                       \
        } while (0)
#define timevalsub(vvp, uvp)                                            \
        do {                                                            \
                (vvp)->tv_sec -= (uvp)->tv_sec;                         \
                (vvp)->tv_usec -= (uvp)->tv_usec;                       \
                if ((vvp)->tv_usec < 0) {                               \
                        (vvp)->tv_sec--;                                \
                        (vvp)->tv_usec += 1000000;                      \
                }                                                       \
        } while (0)

#define ISC_MUTEX_MAX_LOCKERS 32

typedef struct {
	const char *		file;
	int			line;
	unsigned		count;
	struct timeval		locked_total;
	struct timeval		wait_total;
} isc_mutexlocker_t;

struct isc_mutexstats {
	const char *		file;	/* File mutex was created in. */
	int 			line;	/* Line mutex was created on. */
	unsigned		count;
	struct timeval		lock_t;
	struct timeval		locked_total;
	struct timeval		wait_total;
	isc_mutexlocker_t *	cur_locker;
	isc_mutexlocker_t	lockers[ISC_MUTEX_MAX_LOCKERS];
};

#define TABLESIZE (8 * 1024)
static isc_mutexstats_t stats[TABLESIZE];
static isc_boolean_t stats_init = ISC_FALSE;
static pthread_mutex_t statslock = PTHREAD_MUTEX_INITIALIZER;


isc_result_t
isc_mutex_init_profile(isc_mutex_t *mp, const char *file, int line) {
	int i;

	if (pthread_mutex_init(&mp->mutex, NULL) != 0)
		return ISC_R_UNEXPECTED;

	RUNTIME_CHECK(pthread_mutex_lock(&statslock) == 0);

	if (stats_init == ISC_FALSE) {
		for (i = 0; i < TABLESIZE; i++) {
			stats[i].file = NULL;
		}
		stats_init = ISC_TRUE;
	}

	mp->stats = NULL;
	for (i = 0; i < TABLESIZE; i++) {
		if (stats[i].file == NULL) {
			mp->stats = &stats[i];
			break;
		}
	}
	RUNTIME_CHECK(mp->stats != NULL);

	RUNTIME_CHECK(pthread_mutex_unlock(&statslock) == 0);

	mp->stats->file = file;
	mp->stats->line = line;
	mp->stats->count = 0;
	timevalclear(&mp->stats->locked_total);
	timevalclear(&mp->stats->wait_total);
	for (i = 0; i < ISC_MUTEX_MAX_LOCKERS; i++) {
		mp->stats->lockers[i].file = NULL;
		mp->stats->lockers[i].line = 0;
		mp->stats->lockers[i].count = 0;
		timevalclear(&mp->stats->lockers[i].locked_total);
		timevalclear(&mp->stats->lockers[i].wait_total);
	}

	return ISC_R_SUCCESS;
}

isc_result_t
isc_mutex_lock_profile(isc_mutex_t *mp, const char *file, int line) {
	struct timeval prelock_t;
	struct timeval postlock_t;
	isc_mutexlocker_t *locker = NULL;
	int i;

	gettimeofday(&prelock_t, NULL);

	if (pthread_mutex_lock(&mp->mutex) != 0)
		return (ISC_R_UNEXPECTED);

	gettimeofday(&postlock_t, NULL);
	mp->stats->lock_t = postlock_t;

	timevalsub(&postlock_t, &prelock_t);

	mp->stats->count++;
	timevaladd(&mp->stats->wait_total, &postlock_t);

	for (i = 0; i < ISC_MUTEX_MAX_LOCKERS; i++) {
		if (mp->stats->lockers[i].file == NULL) {
			locker = &mp->stats->lockers[i];
			locker->file = file;
			locker->line = line;
			break;
		} else if (mp->stats->lockers[i].file == file &&
			   mp->stats->lockers[i].line == line) {
			locker = &mp->stats->lockers[i];
			break;
		}
	}

	if (locker != NULL) {
		locker->count++;
		timevaladd(&locker->wait_total, &postlock_t);
	}

	mp->stats->cur_locker = locker;

	return ISC_R_SUCCESS;
}

isc_result_t
isc_mutex_unlock_profile(isc_mutex_t *mp, const char *file, int line) {
	struct timeval unlock_t;

	UNUSED(file);
	UNUSED(line);

	if (mp->stats->cur_locker != NULL) {
		gettimeofday(&unlock_t, NULL);
		timevalsub(&unlock_t, &mp->stats->lock_t);
		timevaladd(&mp->stats->locked_total, &unlock_t);
		timevaladd(&mp->stats->cur_locker->locked_total, &unlock_t);
		mp->stats->cur_locker = NULL;
	}

	return ((pthread_mutex_unlock((&mp->mutex)) == 0) ? \
		ISC_R_SUCCESS : ISC_R_UNEXPECTED);
}


void
isc_mutex_statsprofile(FILE *fp) {
	isc_mutexlocker_t *locker;
	int i, j;
	fprintf(fp, "Mutex stats (in us)\n");
	for (i = 0; i < TABLESIZE; i++) {
		if (stats[i].file == NULL)
			continue;
		fprintf(fp, "%-12s %4d: %10u  %lu.%06lu %lu.%06lu\n",
			stats[i].file, stats[i].line, stats[i].count,
			stats[i].locked_total.tv_sec,
			stats[i].locked_total.tv_usec,
			stats[i].wait_total.tv_sec,
			stats[i].wait_total.tv_usec
			);
		for (j = 0; j < ISC_MUTEX_MAX_LOCKERS; j++) {
			locker = &stats[i].lockers[j];
			if (locker->file == NULL)
				continue;
			fprintf(fp, " %-11s %4d: %10u  %lu.%06lu %lu.%06lu\n",
				locker->file, locker->line, locker->count,
				locker->locked_total.tv_sec,
				locker->locked_total.tv_usec,
				locker->wait_total.tv_sec,
				locker->wait_total.tv_usec
				);
		}
	}
}

#endif /* ISC_MUTEX_PROFILE */

#if ISC_MUTEX_DEBUG && defined(PTHREAD_MUTEX_ERRORCHECK)
isc_result_t
isc_mutex_init_errcheck(isc_mutex_t *mp)
{
	pthread_mutexattr_t attr;

	if (pthread_mutexattr_init(&attr) != 0)
		return ISC_R_UNEXPECTED;

	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ERRORCHECK) != 0)
		return ISC_R_UNEXPECTED;
  
	if (pthread_mutex_init(mp, &attr) != 0)
		return ISC_R_UNEXPECTED;

	return ISC_R_SUCCESS;
}
#endif

#if ISC_MUTEX_DEBUG && defined(__NetBSD__) && defined(PTHREAD_MUTEX_ERRORCHECK)
pthread_mutexattr_t isc__mutex_attrs = {
	PTHREAD_MUTEX_ERRORCHECK,	/* m_type */
	0				/* m_flags, which appears to be unused. */
};
#endif