xref: /titanic_50/usr/src/cmd/lockstat/lockstat.c (revision 2eeaed14a5e2ed9bd811643ad5bffc3510ca0310)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <stdio.h>
30 #include <stddef.h>
31 #include <stdlib.h>
32 #include <stdarg.h>
33 #include <string.h>
34 #include <strings.h>
35 #include <ctype.h>
36 #include <fcntl.h>
37 #include <unistd.h>
38 #include <errno.h>
39 #include <limits.h>
40 #include <sys/types.h>
41 #include <sys/modctl.h>
42 #include <sys/stat.h>
43 #include <sys/wait.h>
44 #include <dtrace.h>
45 #include <sys/lockstat.h>
46 #include <alloca.h>
47 #include <signal.h>
48 #include <assert.h>
49 
50 #define	LOCKSTAT_OPTSTR	"x:bths:n:d:i:l:f:e:ckwWgCHEATID:RpPo:V"
51 
52 #define	LS_MAX_STACK_DEPTH	50
53 #define	LS_MAX_EVENTS		64
54 
55 typedef struct lsrec {
56 	struct lsrec	*ls_next;	/* next in hash chain */
57 	uintptr_t	ls_lock;	/* lock address */
58 	uintptr_t	ls_caller;	/* caller address */
59 	uint32_t	ls_count;	/* cumulative event count */
60 	uint32_t	ls_event;	/* type of event */
61 	uintptr_t	ls_refcnt;	/* cumulative reference count */
62 	uint64_t	ls_time;	/* cumulative event duration */
63 	uint32_t	ls_hist[64];	/* log2(duration) histogram */
64 	uintptr_t	ls_stack[LS_MAX_STACK_DEPTH];
65 } lsrec_t;
66 
67 typedef struct lsdata {
68 	struct lsrec	*lsd_next;	/* next available */
69 	int		lsd_count;	/* number of records */
70 } lsdata_t;
71 
72 /*
73  * Definitions for the types of experiments which can be run.  They are
74  * listed in increasing order of memory cost and processing time cost.
75  * The numerical value of each type is the number of bytes needed per record.
76  */
77 #define	LS_BASIC	offsetof(lsrec_t, ls_time)
78 #define	LS_TIME		offsetof(lsrec_t, ls_hist[0])
79 #define	LS_HIST		offsetof(lsrec_t, ls_stack[0])
80 #define	LS_STACK(depth)	offsetof(lsrec_t, ls_stack[depth])
81 
82 static void report_stats(FILE *, lsrec_t **, size_t, uint64_t, uint64_t);
83 static void report_trace(FILE *, lsrec_t **);
84 
85 extern int symtab_init(void);
86 extern char *addr_to_sym(uintptr_t, uintptr_t *, size_t *);
87 extern uintptr_t sym_to_addr(char *name);
88 extern size_t sym_size(char *name);
89 extern char *strtok_r(char *, const char *, char **);
90 
91 #define	DEFAULT_NRECS	10000
92 #define	DEFAULT_HZ	97
93 #define	MAX_HZ		1000
94 #define	MIN_AGGSIZE	(16 * 1024)
95 #define	MAX_AGGSIZE	(32 * 1024 * 1024)
96 
97 static int g_stkdepth;
98 static int g_topn = INT_MAX;
99 static hrtime_t g_elapsed;
100 static int g_rates = 0;
101 static int g_pflag = 0;
102 static int g_Pflag = 0;
103 static int g_wflag = 0;
104 static int g_Wflag = 0;
105 static int g_cflag = 0;
106 static int g_kflag = 0;
107 static int g_gflag = 0;
108 static int g_Vflag = 0;
109 static int g_tracing = 0;
110 static size_t g_recsize;
111 static size_t g_nrecs;
112 static int g_nrecs_used;
113 static uchar_t g_enabled[LS_MAX_EVENTS];
114 static hrtime_t g_min_duration[LS_MAX_EVENTS];
115 static dtrace_hdl_t *g_dtp;
116 static char *g_predicate;
117 static char *g_ipredicate;
118 static char *g_prog;
119 static int g_proglen;
120 static int g_dropped;
121 
122 typedef struct ls_event_info {
123 	char	ev_type;
124 	char	ev_lhdr[20];
125 	char	ev_desc[80];
126 	char	ev_units[10];
127 	char	ev_name[DTRACE_NAMELEN];
128 	char	*ev_predicate;
129 	char	*ev_acquire;
130 } ls_event_info_t;
131 
132 static ls_event_info_t g_event_info[LS_MAX_EVENTS] = {
133 	{ 'C',	"Lock",	"Adaptive mutex spin",			"spin",
134 	    "lockstat:::adaptive-spin" },
135 	{ 'C',	"Lock",	"Adaptive mutex block",			"nsec",
136 	    "lockstat:::adaptive-block" },
137 	{ 'C',	"Lock",	"Spin lock spin",			"spin",
138 	    "lockstat:::spin-spin" },
139 	{ 'C',	"Lock",	"Thread lock spin",			"spin",
140 	    "lockstat:::thread-spin" },
141 	{ 'C',	"Lock",	"R/W writer blocked by writer",		"nsec",
142 	    "lockstat:::rw-block", "arg2 == 0 && arg3 == 1" },
143 	{ 'C',	"Lock",	"R/W writer blocked by readers",	"nsec",
144 	    "lockstat:::rw-block", "arg2 == 0 && arg3 == 0 && arg4" },
145 	{ 'C',	"Lock",	"R/W reader blocked by writer",		"nsec",
146 	    "lockstat:::rw-block", "arg2 != 0 && arg3 == 1" },
147 	{ 'C',	"Lock",	"R/W reader blocked by write wanted",	"nsec",
148 	    "lockstat:::rw-block", "arg2 != 0 && arg3 == 0 && arg4" },
149 	{ 'C',	"Lock",	"Unknown event (type 8)",		"units"	},
150 	{ 'C',	"Lock",	"Unknown event (type 9)",		"units"	},
151 	{ 'C',	"Lock",	"Unknown event (type 10)",		"units"	},
152 	{ 'C',	"Lock",	"Unknown event (type 11)",		"units"	},
153 	{ 'C',	"Lock",	"Unknown event (type 12)",		"units"	},
154 	{ 'C',	"Lock",	"Unknown event (type 13)",		"units"	},
155 	{ 'C',	"Lock",	"Unknown event (type 14)",		"units"	},
156 	{ 'C',	"Lock",	"Unknown event (type 15)",		"units"	},
157 	{ 'C',	"Lock",	"Unknown event (type 16)",		"units"	},
158 	{ 'C',	"Lock",	"Unknown event (type 17)",		"units"	},
159 	{ 'C',	"Lock",	"Unknown event (type 18)",		"units"	},
160 	{ 'C',	"Lock",	"Unknown event (type 19)",		"units"	},
161 	{ 'C',	"Lock",	"Unknown event (type 20)",		"units"	},
162 	{ 'C',	"Lock",	"Unknown event (type 21)",		"units"	},
163 	{ 'C',	"Lock",	"Unknown event (type 22)",		"units"	},
164 	{ 'C',	"Lock",	"Unknown event (type 23)",		"units"	},
165 	{ 'C',	"Lock",	"Unknown event (type 24)",		"units"	},
166 	{ 'C',	"Lock",	"Unknown event (type 25)",		"units"	},
167 	{ 'C',	"Lock",	"Unknown event (type 26)",		"units"	},
168 	{ 'C',	"Lock",	"Unknown event (type 27)",		"units"	},
169 	{ 'C',	"Lock",	"Unknown event (type 28)",		"units"	},
170 	{ 'C',	"Lock",	"Unknown event (type 29)",		"units"	},
171 	{ 'C',	"Lock",	"Unknown event (type 30)",		"units"	},
172 	{ 'C',	"Lock",	"Unknown event (type 31)",		"units"	},
173 	{ 'H',	"Lock",	"Adaptive mutex hold",			"nsec",
174 	    "lockstat:::adaptive-release", NULL,
175 	    "lockstat:::adaptive-acquire" },
176 	{ 'H',	"Lock",	"Spin lock hold",			"nsec",
177 	    "lockstat:::spin-release", NULL,
178 	    "lockstat:::spin-acquire" },
179 	{ 'H',	"Lock",	"R/W writer hold",			"nsec",
180 	    "lockstat:::rw-release", "arg1 == 0",
181 	    "lockstat:::rw-acquire" },
182 	{ 'H',	"Lock",	"R/W reader hold",			"nsec",
183 	    "lockstat:::rw-release", "arg1 != 0",
184 	    "lockstat:::rw-acquire" },
185 	{ 'H',	"Lock",	"Unknown event (type 36)",		"units"	},
186 	{ 'H',	"Lock",	"Unknown event (type 37)",		"units"	},
187 	{ 'H',	"Lock",	"Unknown event (type 38)",		"units"	},
188 	{ 'H',	"Lock",	"Unknown event (type 39)",		"units"	},
189 	{ 'H',	"Lock",	"Unknown event (type 40)",		"units"	},
190 	{ 'H',	"Lock",	"Unknown event (type 41)",		"units"	},
191 	{ 'H',	"Lock",	"Unknown event (type 42)",		"units"	},
192 	{ 'H',	"Lock",	"Unknown event (type 43)",		"units"	},
193 	{ 'H',	"Lock",	"Unknown event (type 44)",		"units"	},
194 	{ 'H',	"Lock",	"Unknown event (type 45)",		"units"	},
195 	{ 'H',	"Lock",	"Unknown event (type 46)",		"units"	},
196 	{ 'H',	"Lock",	"Unknown event (type 47)",		"units"	},
197 	{ 'H',	"Lock",	"Unknown event (type 48)",		"units"	},
198 	{ 'H',	"Lock",	"Unknown event (type 49)",		"units"	},
199 	{ 'H',	"Lock",	"Unknown event (type 50)",		"units"	},
200 	{ 'H',	"Lock",	"Unknown event (type 51)",		"units"	},
201 	{ 'H',	"Lock",	"Unknown event (type 52)",		"units"	},
202 	{ 'H',	"Lock",	"Unknown event (type 53)",		"units"	},
203 	{ 'H',	"Lock",	"Unknown event (type 54)",		"units"	},
204 	{ 'H',	"Lock",	"Unknown event (type 55)",		"units"	},
205 	{ 'I',	"CPU+PIL", "Profiling interrupt",		"nsec",
206 	    "profile:::profile-97", NULL },
207 	{ 'I',	"Lock",	"Unknown event (type 57)",		"units"	},
208 	{ 'I',	"Lock",	"Unknown event (type 58)",		"units"	},
209 	{ 'I',	"Lock",	"Unknown event (type 59)",		"units"	},
210 	{ 'E',	"Lock",	"Recursive lock entry detected",	"(N/A)",
211 	    "lockstat:::rw-release", NULL, "lockstat:::rw-acquire" },
212 	{ 'E',	"Lock",	"Lockstat enter failure",		"(N/A)"	},
213 	{ 'E',	"Lock",	"Lockstat exit failure",		"nsec"	},
214 	{ 'E',	"Lock",	"Lockstat record failure",		"(N/A)"	},
215 };
216 
217 static void
218 fail(int do_perror, const char *message, ...)
219 {
220 	va_list args;
221 	int save_errno = errno;
222 
223 	va_start(args, message);
224 	(void) fprintf(stderr, "lockstat: ");
225 	(void) vfprintf(stderr, message, args);
226 	va_end(args);
227 	if (do_perror)
228 		(void) fprintf(stderr, ": %s", strerror(save_errno));
229 	(void) fprintf(stderr, "\n");
230 	exit(2);
231 }
232 
233 static void
234 dfail(const char *message, ...)
235 {
236 	va_list args;
237 
238 	va_start(args, message);
239 	(void) fprintf(stderr, "lockstat: ");
240 	(void) vfprintf(stderr, message, args);
241 	va_end(args);
242 	(void) fprintf(stderr, ": %s\n",
243 	    dtrace_errmsg(g_dtp, dtrace_errno(g_dtp)));
244 
245 	exit(2);
246 }
247 
248 static void
249 show_events(char event_type, char *desc)
250 {
251 	int i, first = -1, last;
252 
253 	for (i = 0; i < LS_MAX_EVENTS; i++) {
254 		ls_event_info_t *evp = &g_event_info[i];
255 		if (evp->ev_type != event_type ||
256 		    strncmp(evp->ev_desc, "Unknown event", 13) == 0)
257 			continue;
258 		if (first == -1)
259 			first = i;
260 		last = i;
261 	}
262 
263 	(void) fprintf(stderr,
264 	    "\n%s events (lockstat -%c or lockstat -e %d-%d):\n\n",
265 	    desc, event_type, first, last);
266 
267 	for (i = first; i <= last; i++)
268 		(void) fprintf(stderr,
269 		    "%4d = %s\n", i, g_event_info[i].ev_desc);
270 }
271 
272 static void
273 usage(void)
274 {
275 	(void) fprintf(stderr,
276 	    "Usage: lockstat [options] command [args]\n"
277 	    "\nEvent selection options:\n\n"
278 	    "  -C              watch contention events [on by default]\n"
279 	    "  -E              watch error events [off by default]\n"
280 	    "  -H              watch hold events [off by default]\n"
281 	    "  -I              watch interrupt events [off by default]\n"
282 	    "  -A              watch all lock events [equivalent to -CH]\n"
283 	    "  -e event_list   only watch the specified events (shown below);\n"
284 	    "                  <event_list> is a comma-separated list of\n"
285 	    "                  events or ranges of events, e.g. 1,4-7,35\n"
286 	    "  -i rate         interrupt rate for -I [default: %d Hz]\n"
287 	    "\nData gathering options:\n\n"
288 	    "  -b              basic statistics (lock, caller, event count)\n"
289 	    "  -t              timing for all events [default]\n"
290 	    "  -h              histograms for event times\n"
291 	    "  -s depth        stack traces <depth> deep\n"
292 	    "  -x opt[=val]    enable or modify DTrace options\n"
293 	    "\nData filtering options:\n\n"
294 	    "  -n nrecords     maximum number of data records [default: %d]\n"
295 	    "  -l lock[,size]  only watch <lock>, which can be specified as a\n"
296 	    "                  symbolic name or hex address; <size> defaults\n"
297 	    "                  to the ELF symbol size if available, 1 if not\n"
298 	    "  -f func[,size]  only watch events generated by <func>\n"
299 	    "  -d duration     only watch events longer than <duration>\n"
300 	    "  -T              trace (rather than sample) events\n"
301 	    "\nData reporting options:\n\n"
302 	    "  -c              coalesce lock data for arrays like pse_mutex[]\n"
303 	    "  -k              coalesce PCs within functions\n"
304 	    "  -g              show total events generated by function\n"
305 	    "  -w              wherever: don't distinguish events by caller\n"
306 	    "  -W              whichever: don't distinguish events by lock\n"
307 	    "  -R              display rates rather than counts\n"
308 	    "  -p              parsable output format (awk(1)-friendly)\n"
309 	    "  -P              sort lock data by (count * avg_time) product\n"
310 	    "  -D n            only display top <n> events of each type\n"
311 	    "  -o filename     send output to <filename>\n",
312 	    DEFAULT_HZ, DEFAULT_NRECS);
313 
314 	show_events('C', "Contention");
315 	show_events('H', "Hold-time");
316 	show_events('I', "Interrupt");
317 	show_events('E', "Error");
318 	(void) fprintf(stderr, "\n");
319 
320 	exit(1);
321 }
322 
323 static int
324 lockcmp(lsrec_t *a, lsrec_t *b)
325 {
326 	int i;
327 
328 	if (a->ls_event < b->ls_event)
329 		return (-1);
330 	if (a->ls_event > b->ls_event)
331 		return (1);
332 
333 	for (i = g_stkdepth - 1; i >= 0; i--) {
334 		if (a->ls_stack[i] < b->ls_stack[i])
335 			return (-1);
336 		if (a->ls_stack[i] > b->ls_stack[i])
337 			return (1);
338 	}
339 
340 	if (a->ls_caller < b->ls_caller)
341 		return (-1);
342 	if (a->ls_caller > b->ls_caller)
343 		return (1);
344 
345 	if (a->ls_lock < b->ls_lock)
346 		return (-1);
347 	if (a->ls_lock > b->ls_lock)
348 		return (1);
349 
350 	return (0);
351 }
352 
353 static int
354 countcmp(lsrec_t *a, lsrec_t *b)
355 {
356 	if (a->ls_event < b->ls_event)
357 		return (-1);
358 	if (a->ls_event > b->ls_event)
359 		return (1);
360 
361 	return (b->ls_count - a->ls_count);
362 }
363 
364 static int
365 timecmp(lsrec_t *a, lsrec_t *b)
366 {
367 	if (a->ls_event < b->ls_event)
368 		return (-1);
369 	if (a->ls_event > b->ls_event)
370 		return (1);
371 
372 	if (a->ls_time < b->ls_time)
373 		return (1);
374 	if (a->ls_time > b->ls_time)
375 		return (-1);
376 
377 	return (0);
378 }
379 
380 static int
381 lockcmp_anywhere(lsrec_t *a, lsrec_t *b)
382 {
383 	if (a->ls_event < b->ls_event)
384 		return (-1);
385 	if (a->ls_event > b->ls_event)
386 		return (1);
387 
388 	if (a->ls_lock < b->ls_lock)
389 		return (-1);
390 	if (a->ls_lock > b->ls_lock)
391 		return (1);
392 
393 	return (0);
394 }
395 
396 static int
397 lock_and_count_cmp_anywhere(lsrec_t *a, lsrec_t *b)
398 {
399 	if (a->ls_event < b->ls_event)
400 		return (-1);
401 	if (a->ls_event > b->ls_event)
402 		return (1);
403 
404 	if (a->ls_lock < b->ls_lock)
405 		return (-1);
406 	if (a->ls_lock > b->ls_lock)
407 		return (1);
408 
409 	return (b->ls_count - a->ls_count);
410 }
411 
412 static int
413 sitecmp_anylock(lsrec_t *a, lsrec_t *b)
414 {
415 	int i;
416 
417 	if (a->ls_event < b->ls_event)
418 		return (-1);
419 	if (a->ls_event > b->ls_event)
420 		return (1);
421 
422 	for (i = g_stkdepth - 1; i >= 0; i--) {
423 		if (a->ls_stack[i] < b->ls_stack[i])
424 			return (-1);
425 		if (a->ls_stack[i] > b->ls_stack[i])
426 			return (1);
427 	}
428 
429 	if (a->ls_caller < b->ls_caller)
430 		return (-1);
431 	if (a->ls_caller > b->ls_caller)
432 		return (1);
433 
434 	return (0);
435 }
436 
437 static int
438 site_and_count_cmp_anylock(lsrec_t *a, lsrec_t *b)
439 {
440 	int i;
441 
442 	if (a->ls_event < b->ls_event)
443 		return (-1);
444 	if (a->ls_event > b->ls_event)
445 		return (1);
446 
447 	for (i = g_stkdepth - 1; i >= 0; i--) {
448 		if (a->ls_stack[i] < b->ls_stack[i])
449 			return (-1);
450 		if (a->ls_stack[i] > b->ls_stack[i])
451 			return (1);
452 	}
453 
454 	if (a->ls_caller < b->ls_caller)
455 		return (-1);
456 	if (a->ls_caller > b->ls_caller)
457 		return (1);
458 
459 	return (b->ls_count - a->ls_count);
460 }
461 
462 static void
463 mergesort(int (*cmp)(lsrec_t *, lsrec_t *), lsrec_t **a, lsrec_t **b, int n)
464 {
465 	int m = n / 2;
466 	int i, j;
467 
468 	if (m > 1)
469 		mergesort(cmp, a, b, m);
470 	if (n - m > 1)
471 		mergesort(cmp, a + m, b + m, n - m);
472 	for (i = m; i > 0; i--)
473 		b[i - 1] = a[i - 1];
474 	for (j = m - 1; j < n - 1; j++)
475 		b[n + m - j - 2] = a[j + 1];
476 	while (i < j)
477 		*a++ = cmp(b[i], b[j]) < 0 ? b[i++] : b[j--];
478 	*a = b[i];
479 }
480 
481 static void
482 coalesce(int (*cmp)(lsrec_t *, lsrec_t *), lsrec_t **lock, int n)
483 {
484 	int i, j;
485 	lsrec_t *target, *current;
486 
487 	target = lock[0];
488 
489 	for (i = 1; i < n; i++) {
490 		current = lock[i];
491 		if (cmp(current, target) != 0) {
492 			target = current;
493 			continue;
494 		}
495 		current->ls_event = LS_MAX_EVENTS;
496 		target->ls_count += current->ls_count;
497 		target->ls_refcnt += current->ls_refcnt;
498 		if (g_recsize < LS_TIME)
499 			continue;
500 		target->ls_time += current->ls_time;
501 		if (g_recsize < LS_HIST)
502 			continue;
503 		for (j = 0; j < 64; j++)
504 			target->ls_hist[j] += current->ls_hist[j];
505 	}
506 }
507 
508 static void
509 coalesce_symbol(uintptr_t *addrp)
510 {
511 	uintptr_t symoff;
512 	size_t symsize;
513 
514 	if (addr_to_sym(*addrp, &symoff, &symsize) != NULL && symoff < symsize)
515 		*addrp -= symoff;
516 }
517 
518 static void
519 predicate_add(char **pred, char *what, char *cmp, uintptr_t value)
520 {
521 	char *new;
522 	int len, newlen;
523 
524 	if (what == NULL)
525 		return;
526 
527 	if (*pred == NULL) {
528 		*pred = malloc(1);
529 		*pred[0] = '\0';
530 	}
531 
532 	len = strlen(*pred);
533 	newlen = len + strlen(what) + 32 + strlen("( && )");
534 	new = malloc(newlen);
535 
536 	if (*pred[0] != '\0') {
537 		if (cmp != NULL) {
538 			(void) sprintf(new, "(%s) && (%s %s 0x%p)",
539 			    *pred, what, cmp, (void *)value);
540 		} else {
541 			(void) sprintf(new, "(%s) && (%s)", *pred, what);
542 		}
543 	} else {
544 		if (cmp != NULL) {
545 			(void) sprintf(new, "%s %s 0x%p",
546 			    what, cmp, (void *)value);
547 		} else {
548 			(void) sprintf(new, "%s", what);
549 		}
550 	}
551 
552 	free(*pred);
553 	*pred = new;
554 }
555 
556 static void
557 predicate_destroy(char **pred)
558 {
559 	free(*pred);
560 	*pred = NULL;
561 }
562 
563 static void
564 filter_add(char **filt, char *what, uintptr_t base, uintptr_t size)
565 {
566 	char buf[256], *c = buf, *new;
567 	int len, newlen;
568 
569 	if (*filt == NULL) {
570 		*filt = malloc(1);
571 		*filt[0] = '\0';
572 	}
573 
574 	(void) sprintf(c, "%s(%s >= 0x%p && %s < 0x%p)", *filt[0] != '\0' ?
575 	    " || " : "", what, (void *)base, what, (void *)(base + size));
576 
577 	newlen = (len = strlen(*filt) + 1) + strlen(c);
578 	new = malloc(newlen);
579 	bcopy(*filt, new, len);
580 	(void) strcat(new, c);
581 	free(*filt);
582 	*filt = new;
583 }
584 
585 static void
586 filter_destroy(char **filt)
587 {
588 	free(*filt);
589 	*filt = NULL;
590 }
591 
592 static void
593 dprog_add(const char *fmt, ...)
594 {
595 	va_list args;
596 	int size, offs;
597 	char c;
598 
599 	va_start(args, fmt);
600 	size = vsnprintf(&c, 1, fmt, args) + 1;
601 
602 	if (g_proglen == 0) {
603 		offs = 0;
604 	} else {
605 		offs = g_proglen - 1;
606 	}
607 
608 	g_proglen = offs + size;
609 
610 	if ((g_prog = realloc(g_prog, g_proglen)) == NULL)
611 		fail(1, "failed to reallocate program text");
612 
613 	(void) vsnprintf(&g_prog[offs], size, fmt, args);
614 }
615 
616 /*
617  * This function may read like an open sewer, but keep in mind that programs
618  * that generate other programs are rarely pretty.  If one has the unenviable
619  * task of maintaining or -- worse -- extending this code, use the -V option
620  * to examine the D program as generated by this function.
621  */
622 static void
623 dprog_addevent(int event)
624 {
625 	ls_event_info_t *info = &g_event_info[event];
626 	char *pred = NULL;
627 	char stack[20];
628 	const char *arg0, *caller;
629 	char *arg1 = "arg1";
630 	char buf[80];
631 	hrtime_t dur;
632 	int depth;
633 
634 	if (info->ev_name[0] == '\0')
635 		return;
636 
637 	if (info->ev_type == 'I') {
638 		/*
639 		 * For interrupt events, arg0 (normally the lock pointer) is
640 		 * the CPU address plus the current pil, and arg1 (normally
641 		 * the number of nanoseconds) is the number of nanoseconds
642 		 * late -- and it's stored in arg2.
643 		 */
644 		arg0 = "(uintptr_t)curthread->t_cpu + \n"
645 		    "\t    curthread->t_cpu->cpu_profile_pil";
646 		caller = "(uintptr_t)arg0";
647 		arg1 = "arg2";
648 	} else {
649 		arg0 = "(uintptr_t)arg0";
650 		caller = "caller";
651 	}
652 
653 	if (g_recsize > LS_HIST) {
654 		for (depth = 0; g_recsize > LS_STACK(depth); depth++)
655 			continue;
656 
657 		if (g_tracing) {
658 			(void) sprintf(stack, "\tstack(%d);\n", depth);
659 		} else {
660 			(void) sprintf(stack, ", stack(%d)", depth);
661 		}
662 	} else {
663 		(void) sprintf(stack, "");
664 	}
665 
666 	if (info->ev_acquire != NULL) {
667 		/*
668 		 * If this is a hold event, we need to generate an additional
669 		 * clause for the acquire; the clause for the release will be
670 		 * generated with the aggregating statement, below.
671 		 */
672 		dprog_add("%s\n", info->ev_acquire);
673 		predicate_add(&pred, info->ev_predicate, NULL, 0);
674 		predicate_add(&pred, g_predicate, NULL, 0);
675 		if (pred != NULL)
676 			dprog_add("/%s/\n", pred);
677 
678 		dprog_add("{\n");
679 		(void) sprintf(buf, "self->ev%d[(uintptr_t)arg0]", event);
680 
681 		if (info->ev_type == 'H') {
682 			dprog_add("\t%s = timestamp;\n", buf);
683 		} else {
684 			/*
685 			 * If this isn't a hold event, it's the recursive
686 			 * error event.  For this, we simply bump the
687 			 * thread-local, per-lock count.
688 			 */
689 			dprog_add("\t%s++;\n", buf);
690 		}
691 
692 		dprog_add("}\n\n");
693 		predicate_destroy(&pred);
694 		pred = NULL;
695 
696 		if (info->ev_type == 'E') {
697 			/*
698 			 * If this is the recursive lock error event, we need
699 			 * to generate an additional clause to decrement the
700 			 * thread-local, per-lock count.  This assures that we
701 			 * only execute the aggregating clause if we have
702 			 * recursive entry.
703 			 */
704 			dprog_add("%s\n", info->ev_name);
705 			dprog_add("/%s/\n{\n\t%s--;\n}\n\n", buf, buf);
706 		}
707 
708 		predicate_add(&pred, buf, NULL, 0);
709 
710 		if (info->ev_type == 'H') {
711 			(void) sprintf(buf, "timestamp -\n\t    "
712 			    "self->ev%d[(uintptr_t)arg0]", event);
713 		}
714 
715 		arg1 = buf;
716 	} else {
717 		predicate_add(&pred, info->ev_predicate, NULL, 0);
718 		if (info->ev_type != 'I')
719 			predicate_add(&pred, g_predicate, NULL, 0);
720 		else
721 			predicate_add(&pred, g_ipredicate, NULL, 0);
722 	}
723 
724 	if ((dur = g_min_duration[event]) != 0)
725 		predicate_add(&pred, arg1, ">=", dur);
726 
727 	dprog_add("%s\n", info->ev_name);
728 
729 	if (pred != NULL)
730 		dprog_add("/%s/\n", pred);
731 	predicate_destroy(&pred);
732 
733 	dprog_add("{\n");
734 
735 	if (g_tracing) {
736 		dprog_add("\ttrace(%dULL);\n", event);
737 		dprog_add("\ttrace(%s);\n", arg0);
738 		dprog_add("\ttrace(%s);\n", caller);
739 		dprog_add(stack);
740 	} else {
741 		/*
742 		 * The ordering here is important:  when we process the
743 		 * aggregate, we count on the fact that @avg appears before
744 		 * @hist in program order to assure that @avg is assigned the
745 		 * first aggregation variable ID and @hist assigned the
746 		 * second; see the comment in process_aggregate() for details.
747 		 */
748 		dprog_add("\t@avg[%dULL, %s, %s%s] = avg(%s);\n",
749 		    event, arg0, caller, stack, arg1);
750 
751 		if (g_recsize >= LS_HIST) {
752 			dprog_add("\t@hist[%dULL, %s, %s%s] = quantize"
753 			    "(%s);\n", event, arg0, caller, stack, arg1);
754 		}
755 	}
756 
757 	if (info->ev_acquire != NULL)
758 		dprog_add("\tself->ev%d[arg0] = 0;\n", event);
759 
760 	dprog_add("}\n\n");
761 }
762 
763 static void
764 dprog_compile()
765 {
766 	dtrace_prog_t *prog;
767 	dtrace_proginfo_t info;
768 
769 	if (g_Vflag) {
770 		(void) fprintf(stderr, "lockstat: vvvv D program vvvv\n");
771 		(void) fputs(g_prog, stderr);
772 		(void) fprintf(stderr, "lockstat: ^^^^ D program ^^^^\n");
773 	}
774 
775 	if ((prog = dtrace_program_strcompile(g_dtp, g_prog,
776 	    DTRACE_PROBESPEC_NAME, 0, 0, NULL)) == NULL)
777 		dfail("failed to compile program");
778 
779 	if (dtrace_program_exec(g_dtp, prog, &info) == -1)
780 		dfail("failed to enable probes");
781 
782 	if (dtrace_go(g_dtp) != 0)
783 		dfail("couldn't start tracing");
784 }
785 
786 static void
787 status_fire(void)
788 {}
789 
790 static void
791 status_init(void)
792 {
793 	dtrace_optval_t val, status, agg;
794 	struct sigaction act;
795 	struct itimerspec ts;
796 	struct sigevent ev;
797 	timer_t tid;
798 
799 	if (dtrace_getopt(g_dtp, "statusrate", &status) == -1)
800 		dfail("failed to get 'statusrate'");
801 
802 	if (dtrace_getopt(g_dtp, "aggrate", &agg) == -1)
803 		dfail("failed to get 'statusrate'");
804 
805 	/*
806 	 * We would want to awaken at a rate that is the GCD of the statusrate
807 	 * and the aggrate -- but that seems a bit absurd.  Instead, we'll
808 	 * simply awaken at a rate that is the more frequent of the two, which
809 	 * assures that we're never later than the interval implied by the
810 	 * more frequent rate.
811 	 */
812 	val = status < agg ? status : agg;
813 
814 	(void) sigemptyset(&act.sa_mask);
815 	act.sa_flags = 0;
816 	act.sa_handler = status_fire;
817 	(void) sigaction(SIGUSR1, &act, NULL);
818 
819 	ev.sigev_notify = SIGEV_SIGNAL;
820 	ev.sigev_signo = SIGUSR1;
821 
822 	if (timer_create(CLOCK_REALTIME, &ev, &tid) == -1)
823 		dfail("cannot create CLOCK_REALTIME timer");
824 
825 	ts.it_value.tv_sec = val / NANOSEC;
826 	ts.it_value.tv_nsec = val % NANOSEC;
827 	ts.it_interval = ts.it_value;
828 
829 	if (timer_settime(tid, TIMER_RELTIME, &ts, NULL) == -1)
830 		dfail("cannot set time on CLOCK_REALTIME timer");
831 }
832 
833 static void
834 status_check(void)
835 {
836 	if (!g_tracing && dtrace_aggregate_snap(g_dtp) != 0)
837 		dfail("failed to snap aggregate");
838 
839 	if (dtrace_status(g_dtp) == -1)
840 		dfail("dtrace_status()");
841 }
842 
843 static void
844 lsrec_fill(lsrec_t *lsrec, const dtrace_recdesc_t *rec, int nrecs, caddr_t data)
845 {
846 	bzero(lsrec, g_recsize);
847 	lsrec->ls_count = 1;
848 
849 	if ((g_recsize > LS_HIST && nrecs < 4) || (nrecs < 3))
850 		fail(0, "truncated DTrace record");
851 
852 	if (rec->dtrd_size != sizeof (uint64_t))
853 		fail(0, "bad event size in first record");
854 
855 	/* LINTED - alignment */
856 	lsrec->ls_event = (uint32_t)*((uint64_t *)(data + rec->dtrd_offset));
857 	rec++;
858 
859 	if (rec->dtrd_size != sizeof (uintptr_t))
860 		fail(0, "bad lock address size in second record");
861 
862 	/* LINTED - alignment */
863 	lsrec->ls_lock = *((uintptr_t *)(data + rec->dtrd_offset));
864 	rec++;
865 
866 	if (rec->dtrd_size != sizeof (uintptr_t))
867 		fail(0, "bad caller size in third record");
868 
869 	/* LINTED - alignment */
870 	lsrec->ls_caller = *((uintptr_t *)(data + rec->dtrd_offset));
871 	rec++;
872 
873 	if (g_recsize > LS_HIST) {
874 		int frames, i;
875 		pc_t *stack;
876 
877 		frames = rec->dtrd_size / sizeof (pc_t);
878 		/* LINTED - alignment */
879 		stack = (pc_t *)(data + rec->dtrd_offset);
880 
881 		for (i = 1; i < frames; i++)
882 			lsrec->ls_stack[i - 1] = stack[i];
883 	}
884 }
885 
886 /*ARGSUSED*/
887 static int
888 count_aggregate(const dtrace_aggdata_t *agg, void *arg)
889 {
890 	*((size_t *)arg) += 1;
891 
892 	return (DTRACE_AGGWALK_NEXT);
893 }
894 
895 static int
896 process_aggregate(const dtrace_aggdata_t *agg, void *arg)
897 {
898 	const dtrace_aggdesc_t *aggdesc = agg->dtada_desc;
899 	caddr_t data = agg->dtada_data;
900 	lsdata_t *lsdata = arg;
901 	lsrec_t *lsrec = lsdata->lsd_next;
902 	const dtrace_recdesc_t *rec;
903 	uint64_t *avg, *quantized;
904 	int i, j;
905 
906 	assert(lsdata->lsd_count < g_nrecs);
907 
908 	/*
909 	 * Aggregation variable IDs are guaranteed to be generated in program
910 	 * order, and they are guaranteed to start from DTRACE_AGGVARIDNONE
911 	 * plus one.  As "avg" appears before "hist" in program order, we know
912 	 * that "avg" will be allocated the first aggregation variable ID, and
913 	 * "hist" will be allocated the second aggregation variable ID -- and
914 	 * we therefore use the aggregation variable ID to differentiate the
915 	 * cases.
916 	 */
917 	if (aggdesc->dtagd_varid > DTRACE_AGGVARIDNONE + 1) {
918 		/*
919 		 * If this is the histogram entry.  We'll copy the quantized
920 		 * data into lc_hist, and jump over the rest.
921 		 */
922 		rec = &aggdesc->dtagd_rec[aggdesc->dtagd_nrecs - 1];
923 
924 		if (aggdesc->dtagd_varid != DTRACE_AGGVARIDNONE + 2)
925 			fail(0, "bad variable ID in aggregation record");
926 
927 		if (rec->dtrd_size !=
928 		    DTRACE_QUANTIZE_NBUCKETS * sizeof (uint64_t))
929 			fail(0, "bad quantize size in aggregation record");
930 
931 		/* LINTED - alignment */
932 		quantized = (uint64_t *)(data + rec->dtrd_offset);
933 
934 		for (i = DTRACE_QUANTIZE_ZEROBUCKET, j = 0;
935 		    i < DTRACE_QUANTIZE_NBUCKETS; i++, j++)
936 			lsrec->ls_hist[j] = quantized[i];
937 
938 		goto out;
939 	}
940 
941 	lsrec_fill(lsrec, &aggdesc->dtagd_rec[1],
942 	    aggdesc->dtagd_nrecs - 1, data);
943 
944 	rec = &aggdesc->dtagd_rec[aggdesc->dtagd_nrecs - 1];
945 
946 	if (rec->dtrd_size != 2 * sizeof (uint64_t))
947 		fail(0, "bad avg size in aggregation record");
948 
949 	/* LINTED - alignment */
950 	avg = (uint64_t *)(data + rec->dtrd_offset);
951 	lsrec->ls_count = (uint32_t)avg[0];
952 	lsrec->ls_time = (uintptr_t)avg[1];
953 
954 	if (g_recsize >= LS_HIST)
955 		return (DTRACE_AGGWALK_NEXT);
956 
957 out:
958 	lsdata->lsd_next = (lsrec_t *)((uintptr_t)lsrec + g_recsize);
959 	lsdata->lsd_count++;
960 
961 	return (DTRACE_AGGWALK_NEXT);
962 }
963 
964 static int
965 process_trace(const dtrace_probedata_t *pdata, void *arg)
966 {
967 	lsdata_t *lsdata = arg;
968 	lsrec_t *lsrec = lsdata->lsd_next;
969 	dtrace_eprobedesc_t *edesc = pdata->dtpda_edesc;
970 	caddr_t data = pdata->dtpda_data;
971 
972 	if (lsdata->lsd_count >= g_nrecs)
973 		return (DTRACE_CONSUME_NEXT);
974 
975 	lsrec_fill(lsrec, edesc->dtepd_rec, edesc->dtepd_nrecs, data);
976 
977 	lsdata->lsd_next = (lsrec_t *)((uintptr_t)lsrec + g_recsize);
978 	lsdata->lsd_count++;
979 
980 	return (DTRACE_CONSUME_NEXT);
981 }
982 
983 static int
984 process_data(FILE *out, char *data)
985 {
986 	lsdata_t lsdata;
987 
988 	/* LINTED - alignment */
989 	lsdata.lsd_next = (lsrec_t *)data;
990 	lsdata.lsd_count = 0;
991 
992 	if (g_tracing) {
993 		if (dtrace_consume(g_dtp, out,
994 		    process_trace, NULL, &lsdata) != 0)
995 			dfail("failed to consume buffer");
996 
997 		return (lsdata.lsd_count);
998 	}
999 
1000 	if (dtrace_aggregate_walk_keyvarsorted(g_dtp,
1001 	    process_aggregate, &lsdata) != 0)
1002 		dfail("failed to walk aggregate");
1003 
1004 	return (lsdata.lsd_count);
1005 }
1006 
1007 /*ARGSUSED*/
1008 static int
1009 drophandler(const dtrace_dropdata_t *data, void *arg)
1010 {
1011 	g_dropped++;
1012 	(void) fprintf(stderr, "lockstat: warning: %s", data->dtdda_msg);
1013 	return (DTRACE_HANDLE_OK);
1014 }
1015 
1016 int
1017 main(int argc, char **argv)
1018 {
1019 	char *data_buf;
1020 	lsrec_t *lsp, **current, **first, **sort_buf, **merge_buf;
1021 	FILE *out = stdout;
1022 	char c;
1023 	pid_t child;
1024 	int status;
1025 	int i, j;
1026 	hrtime_t duration;
1027 	char *addrp, *offp, *sizep, *evp, *lastp, *p;
1028 	uintptr_t addr;
1029 	size_t size, off;
1030 	int events_specified = 0;
1031 	int exec_errno = 0;
1032 	uint32_t event;
1033 	char *filt = NULL, *ifilt = NULL;
1034 	static uint64_t ev_count[LS_MAX_EVENTS + 1];
1035 	static uint64_t ev_time[LS_MAX_EVENTS + 1];
1036 	dtrace_optval_t aggsize;
1037 	char aggstr[10];
1038 	long ncpus;
1039 	int dynvar = 0;
1040 	int err;
1041 
1042 	if ((g_dtp = dtrace_open(DTRACE_VERSION, 0, &err)) == NULL) {
1043 		fail(0, "cannot open dtrace library: %s",
1044 		    dtrace_errmsg(NULL, err));
1045 	}
1046 
1047 	if (dtrace_handle_drop(g_dtp, &drophandler, NULL) == -1)
1048 		dfail("couldn't establish drop handler");
1049 
1050 	if (symtab_init() == -1)
1051 		fail(1, "can't load kernel symbols");
1052 
1053 	g_nrecs = DEFAULT_NRECS;
1054 
1055 	while ((c = getopt(argc, argv, LOCKSTAT_OPTSTR)) != EOF) {
1056 		switch (c) {
1057 		case 'b':
1058 			g_recsize = LS_BASIC;
1059 			break;
1060 
1061 		case 't':
1062 			g_recsize = LS_TIME;
1063 			break;
1064 
1065 		case 'h':
1066 			g_recsize = LS_HIST;
1067 			break;
1068 
1069 		case 's':
1070 			if (!isdigit(optarg[0]))
1071 				usage();
1072 			g_stkdepth = atoi(optarg);
1073 			if (g_stkdepth > LS_MAX_STACK_DEPTH)
1074 				fail(0, "max stack depth is %d",
1075 				    LS_MAX_STACK_DEPTH);
1076 			g_recsize = LS_STACK(g_stkdepth);
1077 			break;
1078 
1079 		case 'n':
1080 			if (!isdigit(optarg[0]))
1081 				usage();
1082 			g_nrecs = atoi(optarg);
1083 			break;
1084 
1085 		case 'd':
1086 			if (!isdigit(optarg[0]))
1087 				usage();
1088 			duration = atoll(optarg);
1089 
1090 			/*
1091 			 * XXX -- durations really should be per event
1092 			 * since the units are different, but it's hard
1093 			 * to express this nicely in the interface.
1094 			 * Not clear yet what the cleanest solution is.
1095 			 */
1096 			for (i = 0; i < LS_MAX_EVENTS; i++)
1097 				if (g_event_info[i].ev_type != 'E')
1098 					g_min_duration[i] = duration;
1099 
1100 			break;
1101 
1102 		case 'i':
1103 			if (!isdigit(optarg[0]))
1104 				usage();
1105 			i = atoi(optarg);
1106 			if (i <= 0)
1107 				usage();
1108 			if (i > MAX_HZ)
1109 				fail(0, "max interrupt rate is %d Hz", MAX_HZ);
1110 
1111 			for (j = 0; j < LS_MAX_EVENTS; j++)
1112 				if (strcmp(g_event_info[j].ev_desc,
1113 				    "Profiling interrupt") == 0)
1114 					break;
1115 
1116 			(void) sprintf(g_event_info[j].ev_name,
1117 			    "profile:::profile-%d", i);
1118 			break;
1119 
1120 		case 'l':
1121 		case 'f':
1122 			addrp = strtok(optarg, ",");
1123 			sizep = strtok(NULL, ",");
1124 			addrp = strtok(optarg, ",+");
1125 			offp = strtok(NULL, ",");
1126 
1127 			size = sizep ? strtoul(sizep, NULL, 0) : 1;
1128 			off = offp ? strtoul(offp, NULL, 0) : 0;
1129 
1130 			if (addrp[0] == '0') {
1131 				addr = strtoul(addrp, NULL, 16) + off;
1132 			} else {
1133 				addr = sym_to_addr(addrp) + off;
1134 				if (sizep == NULL)
1135 					size = sym_size(addrp) - off;
1136 				if (addr - off == 0)
1137 					fail(0, "symbol '%s' not found", addrp);
1138 				if (size == 0)
1139 					size = 1;
1140 			}
1141 
1142 
1143 			if (c == 'l') {
1144 				filter_add(&filt, "arg0", addr, size);
1145 			} else {
1146 				filter_add(&filt, "caller", addr, size);
1147 				filter_add(&ifilt, "arg0", addr, size);
1148 			}
1149 			break;
1150 
1151 		case 'e':
1152 			evp = strtok_r(optarg, ",", &lastp);
1153 			while (evp) {
1154 				int ev1, ev2;
1155 				char *evp2;
1156 
1157 				(void) strtok(evp, "-");
1158 				evp2 = strtok(NULL, "-");
1159 				ev1 = atoi(evp);
1160 				ev2 = evp2 ? atoi(evp2) : ev1;
1161 				if ((uint_t)ev1 >= LS_MAX_EVENTS ||
1162 				    (uint_t)ev2 >= LS_MAX_EVENTS || ev1 > ev2)
1163 					fail(0, "-e events out of range");
1164 				for (i = ev1; i <= ev2; i++)
1165 					g_enabled[i] = 1;
1166 				evp = strtok_r(NULL, ",", &lastp);
1167 			}
1168 			events_specified = 1;
1169 			break;
1170 
1171 		case 'c':
1172 			g_cflag = 1;
1173 			break;
1174 
1175 		case 'k':
1176 			g_kflag = 1;
1177 			break;
1178 
1179 		case 'w':
1180 			g_wflag = 1;
1181 			break;
1182 
1183 		case 'W':
1184 			g_Wflag = 1;
1185 			break;
1186 
1187 		case 'g':
1188 			g_gflag = 1;
1189 			break;
1190 
1191 		case 'C':
1192 		case 'E':
1193 		case 'H':
1194 		case 'I':
1195 			for (i = 0; i < LS_MAX_EVENTS; i++)
1196 				if (g_event_info[i].ev_type == c)
1197 					g_enabled[i] = 1;
1198 			events_specified = 1;
1199 			break;
1200 
1201 		case 'A':
1202 			for (i = 0; i < LS_MAX_EVENTS; i++)
1203 				if (strchr("CH", g_event_info[i].ev_type))
1204 					g_enabled[i] = 1;
1205 			events_specified = 1;
1206 			break;
1207 
1208 		case 'T':
1209 			g_tracing = 1;
1210 			break;
1211 
1212 		case 'D':
1213 			if (!isdigit(optarg[0]))
1214 				usage();
1215 			g_topn = atoi(optarg);
1216 			break;
1217 
1218 		case 'R':
1219 			g_rates = 1;
1220 			break;
1221 
1222 		case 'p':
1223 			g_pflag = 1;
1224 			break;
1225 
1226 		case 'P':
1227 			g_Pflag = 1;
1228 			break;
1229 
1230 		case 'o':
1231 			if ((out = fopen(optarg, "w")) == NULL)
1232 				fail(1, "error opening file");
1233 			break;
1234 
1235 		case 'V':
1236 			g_Vflag = 1;
1237 			break;
1238 
1239 		default:
1240 			if (strchr(LOCKSTAT_OPTSTR, c) == NULL)
1241 				usage();
1242 		}
1243 	}
1244 
1245 	if (filt != NULL) {
1246 		predicate_add(&g_predicate, filt, NULL, 0);
1247 		filter_destroy(&filt);
1248 	}
1249 
1250 	if (ifilt != NULL) {
1251 		predicate_add(&g_ipredicate, ifilt, NULL, 0);
1252 		filter_destroy(&ifilt);
1253 	}
1254 
1255 	if (g_recsize == 0) {
1256 		if (g_gflag) {
1257 			g_stkdepth = LS_MAX_STACK_DEPTH;
1258 			g_recsize = LS_STACK(g_stkdepth);
1259 		} else {
1260 			g_recsize = LS_TIME;
1261 		}
1262 	}
1263 
1264 	if (g_gflag && g_recsize <= LS_STACK(0))
1265 		fail(0, "'-g' requires at least '-s 1' data gathering");
1266 
1267 	/*
1268 	 * Make sure the alignment is reasonable
1269 	 */
1270 	g_recsize = -(-g_recsize & -sizeof (uint64_t));
1271 
1272 	for (i = 0; i < LS_MAX_EVENTS; i++) {
1273 		/*
1274 		 * If no events were specified, enable -C.
1275 		 */
1276 		if (!events_specified && g_event_info[i].ev_type == 'C')
1277 			g_enabled[i] = 1;
1278 	}
1279 
1280 	for (i = 0; i < LS_MAX_EVENTS; i++) {
1281 		if (!g_enabled[i])
1282 			continue;
1283 
1284 		if (g_event_info[i].ev_acquire != NULL) {
1285 			/*
1286 			 * If we've enabled a hold event, we must explicitly
1287 			 * allocate dynamic variable space.
1288 			 */
1289 			dynvar = 1;
1290 		}
1291 
1292 		dprog_addevent(i);
1293 	}
1294 
1295 	/*
1296 	 * Make sure there are remaining arguments to specify a child command
1297 	 * to execute.
1298 	 */
1299 	if (argc <= optind)
1300 		usage();
1301 
1302 	if ((ncpus = sysconf(_SC_NPROCESSORS_ONLN)) == -1)
1303 		dfail("couldn't determine number of online CPUs");
1304 
1305 	/*
1306 	 * By default, we set our data buffer size to be the number of records
1307 	 * multiplied by the size of the record, doubled to account for some
1308 	 * DTrace slop and divided by the number of CPUs.  We silently clamp
1309 	 * the aggregation size at both a minimum and a maximum to prevent
1310 	 * absurdly low or high values.
1311 	 */
1312 	if ((aggsize = (g_nrecs * g_recsize * 2) / ncpus) < MIN_AGGSIZE)
1313 		aggsize = MIN_AGGSIZE;
1314 
1315 	if (aggsize > MAX_AGGSIZE)
1316 		aggsize = MAX_AGGSIZE;
1317 
1318 	(void) sprintf(aggstr, "%lld", (long long)aggsize);
1319 
1320 	if (!g_tracing) {
1321 		if (dtrace_setopt(g_dtp, "bufsize", "4k") == -1)
1322 			dfail("failed to set 'bufsize'");
1323 
1324 		if (dtrace_setopt(g_dtp, "aggsize", aggstr) == -1)
1325 			dfail("failed to set 'aggsize'");
1326 
1327 		if (dynvar) {
1328 			/*
1329 			 * If we're using dynamic variables, we set our
1330 			 * dynamic variable size to be one megabyte per CPU,
1331 			 * with a hard-limit of 32 megabytes.  This may still
1332 			 * be too small in some cases, but it can be tuned
1333 			 * manually via -x if need be.
1334 			 */
1335 			(void) sprintf(aggstr, "%ldm", ncpus < 32 ? ncpus : 32);
1336 
1337 			if (dtrace_setopt(g_dtp, "dynvarsize", aggstr) == -1)
1338 				dfail("failed to set 'dynvarsize'");
1339 		}
1340 	} else {
1341 		if (dtrace_setopt(g_dtp, "bufsize", aggstr) == -1)
1342 			dfail("failed to set 'bufsize'");
1343 	}
1344 
1345 	if (dtrace_setopt(g_dtp, "statusrate", "10sec") == -1)
1346 		dfail("failed to set 'statusrate'");
1347 
1348 	optind = 1;
1349 	while ((c = getopt(argc, argv, LOCKSTAT_OPTSTR)) != EOF) {
1350 		switch (c) {
1351 		case 'x':
1352 			if ((p = strchr(optarg, '=')) != NULL)
1353 				*p++ = '\0';
1354 
1355 			if (dtrace_setopt(g_dtp, optarg, p) != 0)
1356 				dfail("failed to set -x %s", optarg);
1357 			break;
1358 		}
1359 	}
1360 
1361 	argc -= optind;
1362 	argv += optind;
1363 
1364 	dprog_compile();
1365 	status_init();
1366 
1367 	g_elapsed = -gethrtime();
1368 
1369 	/*
1370 	 * Spawn the specified command and wait for it to complete.
1371 	 */
1372 	child = fork();
1373 	if (child == -1)
1374 		fail(1, "cannot fork");
1375 	if (child == 0) {
1376 		(void) dtrace_close(g_dtp);
1377 		(void) execvp(argv[0], &argv[0]);
1378 		exec_errno = errno;
1379 		exit(127);
1380 	}
1381 
1382 	while (waitpid(child, &status, WEXITED) != child)
1383 		status_check();
1384 
1385 	g_elapsed += gethrtime();
1386 
1387 	if (WIFEXITED(status)) {
1388 		if (WEXITSTATUS(status) != 0) {
1389 			if (exec_errno != 0) {
1390 				errno = exec_errno;
1391 				fail(1, "could not execute %s", argv[0]);
1392 			}
1393 			(void) fprintf(stderr,
1394 			    "lockstat: warning: %s exited with code %d\n",
1395 				argv[0], WEXITSTATUS(status));
1396 		}
1397 	} else {
1398 		(void) fprintf(stderr,
1399 		    "lockstat: warning: %s died on signal %d\n",
1400 			argv[0], WTERMSIG(status));
1401 	}
1402 
1403 	if (dtrace_stop(g_dtp) == -1)
1404 		dfail("failed to stop dtrace");
1405 
1406 	/*
1407 	 * Before we read out the results, we need to allocate our buffer.
1408 	 * If we're tracing, then we'll just use the precalculated size.  If
1409 	 * we're not, then we'll take a snapshot of the aggregate, and walk
1410 	 * it to count the number of records.
1411 	 */
1412 	if (!g_tracing) {
1413 		if (dtrace_aggregate_snap(g_dtp) != 0)
1414 			dfail("failed to snap aggregate");
1415 
1416 		g_nrecs = 0;
1417 
1418 		if (dtrace_aggregate_walk(g_dtp,
1419 		    count_aggregate, &g_nrecs) != 0)
1420 			dfail("failed to walk aggregate");
1421 	}
1422 
1423 	if ((data_buf = memalign(sizeof (uint64_t),
1424 	    (g_nrecs + 1) * g_recsize)) == NULL)
1425 		fail(1, "Memory allocation failed");
1426 
1427 	/*
1428 	 * Read out the DTrace data.
1429 	 */
1430 	g_nrecs_used = process_data(out, data_buf);
1431 
1432 	if (g_nrecs_used > g_nrecs || g_dropped)
1433 		(void) fprintf(stderr, "lockstat: warning: "
1434 		    "ran out of data records (use -n for more)\n");
1435 
1436 	/* LINTED - alignment */
1437 	for (i = 0, lsp = (lsrec_t *)data_buf; i < g_nrecs_used; i++,
1438 	    /* LINTED - alignment */
1439 	    lsp = (lsrec_t *)((char *)lsp + g_recsize)) {
1440 		ev_count[lsp->ls_event] += lsp->ls_count;
1441 		ev_time[lsp->ls_event] += lsp->ls_time;
1442 	}
1443 
1444 	/*
1445 	 * If -g was specified, convert stacks into individual records.
1446 	 */
1447 	if (g_gflag) {
1448 		lsrec_t *newlsp, *oldlsp;
1449 
1450 		newlsp = memalign(sizeof (uint64_t),
1451 		    g_nrecs_used * LS_TIME * (g_stkdepth + 1));
1452 		if (newlsp == NULL)
1453 			fail(1, "Cannot allocate space for -g processing");
1454 		lsp = newlsp;
1455 		/* LINTED - alignment */
1456 		for (i = 0, oldlsp = (lsrec_t *)data_buf; i < g_nrecs_used; i++,
1457 		    /* LINTED - alignment */
1458 		    oldlsp = (lsrec_t *)((char *)oldlsp + g_recsize)) {
1459 			int fr;
1460 			int caller_in_stack = 0;
1461 
1462 			if (oldlsp->ls_count == 0)
1463 				continue;
1464 
1465 			for (fr = 0; fr < g_stkdepth; fr++) {
1466 				if (oldlsp->ls_stack[fr] == 0)
1467 					break;
1468 				if (oldlsp->ls_stack[fr] == oldlsp->ls_caller)
1469 					caller_in_stack = 1;
1470 				bcopy(oldlsp, lsp, LS_TIME);
1471 				lsp->ls_caller = oldlsp->ls_stack[fr];
1472 				/* LINTED - alignment */
1473 				lsp = (lsrec_t *)((char *)lsp + LS_TIME);
1474 			}
1475 			if (!caller_in_stack) {
1476 				bcopy(oldlsp, lsp, LS_TIME);
1477 				/* LINTED - alignment */
1478 				lsp = (lsrec_t *)((char *)lsp + LS_TIME);
1479 			}
1480 		}
1481 		g_nrecs = g_nrecs_used =
1482 		    ((uintptr_t)lsp - (uintptr_t)newlsp) / LS_TIME;
1483 		g_recsize = LS_TIME;
1484 		g_stkdepth = 0;
1485 		free(data_buf);
1486 		data_buf = (char *)newlsp;
1487 	}
1488 
1489 	if ((sort_buf = calloc(2 * (g_nrecs + 1),
1490 	    sizeof (void *))) == NULL)
1491 		fail(1, "Sort buffer allocation failed");
1492 	merge_buf = sort_buf + (g_nrecs + 1);
1493 
1494 	/*
1495 	 * Build the sort buffer, discarding zero-count records along the way.
1496 	 */
1497 	/* LINTED - alignment */
1498 	for (i = 0, lsp = (lsrec_t *)data_buf; i < g_nrecs_used; i++,
1499 	    /* LINTED - alignment */
1500 	    lsp = (lsrec_t *)((char *)lsp + g_recsize)) {
1501 		if (lsp->ls_count == 0)
1502 			lsp->ls_event = LS_MAX_EVENTS;
1503 		sort_buf[i] = lsp;
1504 	}
1505 
1506 	if (g_nrecs_used == 0)
1507 		exit(0);
1508 
1509 	/*
1510 	 * Add a sentinel after the last record
1511 	 */
1512 	sort_buf[i] = lsp;
1513 	lsp->ls_event = LS_MAX_EVENTS;
1514 
1515 	if (g_tracing) {
1516 		report_trace(out, sort_buf);
1517 		return (0);
1518 	}
1519 
1520 	/*
1521 	 * Application of -g may have resulted in multiple records
1522 	 * with the same signature; coalesce them.
1523 	 */
1524 	if (g_gflag) {
1525 		mergesort(lockcmp, sort_buf, merge_buf, g_nrecs_used);
1526 		coalesce(lockcmp, sort_buf, g_nrecs_used);
1527 	}
1528 
1529 	/*
1530 	 * Coalesce locks within the same symbol if -c option specified.
1531 	 * Coalesce PCs within the same function if -k option specified.
1532 	 */
1533 	if (g_cflag || g_kflag) {
1534 		for (i = 0; i < g_nrecs_used; i++) {
1535 			int fr;
1536 			lsp = sort_buf[i];
1537 			if (g_cflag)
1538 				coalesce_symbol(&lsp->ls_lock);
1539 			if (g_kflag) {
1540 				for (fr = 0; fr < g_stkdepth; fr++)
1541 					coalesce_symbol(&lsp->ls_stack[fr]);
1542 				coalesce_symbol(&lsp->ls_caller);
1543 			}
1544 		}
1545 		mergesort(lockcmp, sort_buf, merge_buf, g_nrecs_used);
1546 		coalesce(lockcmp, sort_buf, g_nrecs_used);
1547 	}
1548 
1549 	/*
1550 	 * Coalesce callers if -w option specified
1551 	 */
1552 	if (g_wflag) {
1553 		mergesort(lock_and_count_cmp_anywhere,
1554 		    sort_buf, merge_buf, g_nrecs_used);
1555 		coalesce(lockcmp_anywhere, sort_buf, g_nrecs_used);
1556 	}
1557 
1558 	/*
1559 	 * Coalesce locks if -W option specified
1560 	 */
1561 	if (g_Wflag) {
1562 		mergesort(site_and_count_cmp_anylock,
1563 		    sort_buf, merge_buf, g_nrecs_used);
1564 		coalesce(sitecmp_anylock, sort_buf, g_nrecs_used);
1565 	}
1566 
1567 	/*
1568 	 * Sort data by contention count (ls_count) or total time (ls_time),
1569 	 * depending on g_Pflag.  Override g_Pflag if time wasn't measured.
1570 	 */
1571 	if (g_recsize < LS_TIME)
1572 		g_Pflag = 0;
1573 
1574 	if (g_Pflag)
1575 		mergesort(timecmp, sort_buf, merge_buf, g_nrecs_used);
1576 	else
1577 		mergesort(countcmp, sort_buf, merge_buf, g_nrecs_used);
1578 
1579 	/*
1580 	 * Display data by event type
1581 	 */
1582 	first = &sort_buf[0];
1583 	while ((event = (*first)->ls_event) < LS_MAX_EVENTS) {
1584 		current = first;
1585 		while ((lsp = *current)->ls_event == event)
1586 			current++;
1587 		report_stats(out, first, current - first, ev_count[event],
1588 		    ev_time[event]);
1589 		first = current;
1590 	}
1591 
1592 	return (0);
1593 }
1594 
1595 static char *
1596 format_symbol(char *buf, uintptr_t addr, int show_size)
1597 {
1598 	uintptr_t symoff;
1599 	char *symname;
1600 	size_t symsize;
1601 
1602 	symname = addr_to_sym(addr, &symoff, &symsize);
1603 
1604 	if (show_size && symoff == 0)
1605 		(void) sprintf(buf, "%s[%ld]", symname, (long)symsize);
1606 	else if (symoff == 0)
1607 		(void) sprintf(buf, "%s", symname);
1608 	else if (symoff < 16 && bcmp(symname, "cpu[", 4) == 0)	/* CPU+PIL */
1609 		(void) sprintf(buf, "%s+%ld", symname, (long)symoff);
1610 	else if (symoff <= symsize || (symoff < 256 && addr != symoff))
1611 		(void) sprintf(buf, "%s+0x%llx", symname,
1612 		    (unsigned long long)symoff);
1613 	else
1614 		(void) sprintf(buf, "0x%llx", (unsigned long long)addr);
1615 	return (buf);
1616 }
1617 
1618 static void
1619 report_stats(FILE *out, lsrec_t **sort_buf, size_t nrecs, uint64_t total_count,
1620 	uint64_t total_time)
1621 {
1622 	uint32_t event = sort_buf[0]->ls_event;
1623 	lsrec_t *lsp;
1624 	double ptotal = 0.0;
1625 	double percent;
1626 	int i, j, fr;
1627 	int displayed;
1628 	int first_bin, last_bin, max_bin_count, total_bin_count;
1629 	int rectype;
1630 	char buf[256];
1631 	char lhdr[80], chdr[80];
1632 
1633 	rectype = g_recsize;
1634 
1635 	if (g_topn == 0) {
1636 		(void) fprintf(out, "%20llu %s\n",
1637 		    g_rates == 0 ? total_count :
1638 		    ((unsigned long long)total_count * NANOSEC) / g_elapsed,
1639 		    g_event_info[event].ev_desc);
1640 		return;
1641 	}
1642 
1643 	(void) sprintf(lhdr, "%s%s",
1644 	    g_Wflag ? "Hottest " : "", g_event_info[event].ev_lhdr);
1645 	(void) sprintf(chdr, "%s%s",
1646 	    g_wflag ? "Hottest " : "", "Caller");
1647 
1648 	if (!g_pflag)
1649 		(void) fprintf(out,
1650 		    "\n%s: %.0f events in %.3f seconds (%.0f events/sec)\n\n",
1651 		    g_event_info[event].ev_desc, (double)total_count,
1652 		    (double)g_elapsed / NANOSEC,
1653 		    (double)total_count * NANOSEC / g_elapsed);
1654 
1655 	if (!g_pflag && rectype < LS_HIST) {
1656 		(void) sprintf(buf, "%s", g_event_info[event].ev_units);
1657 		(void) fprintf(out, "%5s %4s %4s %4s %8s %-22s %-24s\n",
1658 		    g_rates ? "ops/s" : "Count",
1659 		    g_gflag ? "genr" : "indv",
1660 		    "cuml", "rcnt", rectype >= LS_TIME ? buf : "", lhdr, chdr);
1661 		(void) fprintf(out, "---------------------------------"
1662 		    "----------------------------------------------\n");
1663 	}
1664 
1665 	displayed = 0;
1666 	for (i = 0; i < nrecs; i++) {
1667 		lsp = sort_buf[i];
1668 
1669 		if (displayed++ >= g_topn)
1670 			break;
1671 
1672 		if (g_pflag) {
1673 			int j;
1674 
1675 			(void) fprintf(out, "%u %u",
1676 			    lsp->ls_event, lsp->ls_count);
1677 			(void) fprintf(out, " %s",
1678 			    format_symbol(buf, lsp->ls_lock, g_cflag));
1679 			(void) fprintf(out, " %s",
1680 			    format_symbol(buf, lsp->ls_caller, 0));
1681 			(void) fprintf(out, " %f",
1682 			    (double)lsp->ls_refcnt / lsp->ls_count);
1683 			if (rectype >= LS_TIME)
1684 				(void) fprintf(out, " %llu",
1685 				    (unsigned long long)lsp->ls_time);
1686 			if (rectype >= LS_HIST) {
1687 				for (j = 0; j < 64; j++)
1688 					(void) fprintf(out, " %u",
1689 					    lsp->ls_hist[j]);
1690 			}
1691 			for (j = 0; j < LS_MAX_STACK_DEPTH; j++) {
1692 				if (rectype <= LS_STACK(j) ||
1693 				    lsp->ls_stack[j] == 0)
1694 					break;
1695 				(void) fprintf(out, " %s",
1696 				    format_symbol(buf, lsp->ls_stack[j], 0));
1697 			}
1698 			(void) fprintf(out, "\n");
1699 			continue;
1700 		}
1701 
1702 		if (rectype >= LS_HIST) {
1703 			(void) fprintf(out, "---------------------------------"
1704 			    "----------------------------------------------\n");
1705 			(void) sprintf(buf, "%s",
1706 			    g_event_info[event].ev_units);
1707 			(void) fprintf(out, "%5s %4s %4s %4s %8s %-22s %-24s\n",
1708 			    g_rates ? "ops/s" : "Count",
1709 			    g_gflag ? "genr" : "indv",
1710 			    "cuml", "rcnt", buf, lhdr, chdr);
1711 		}
1712 
1713 		if (g_Pflag && total_time != 0)
1714 			percent = (lsp->ls_time * 100.00) / total_time;
1715 		else
1716 			percent = (lsp->ls_count * 100.00) / total_count;
1717 
1718 		ptotal += percent;
1719 
1720 		if (rectype >= LS_TIME)
1721 			(void) sprintf(buf, "%llu",
1722 			    (unsigned long long)(lsp->ls_time / lsp->ls_count));
1723 		else
1724 			buf[0] = '\0';
1725 
1726 		(void) fprintf(out, "%5llu ",
1727 		    g_rates == 0 ? lsp->ls_count :
1728 		    ((uint64_t)lsp->ls_count * NANOSEC) / g_elapsed);
1729 
1730 		(void) fprintf(out, "%3.0f%% ", percent);
1731 
1732 		if (g_gflag)
1733 			(void) fprintf(out, "---- ");
1734 		else
1735 			(void) fprintf(out, "%3.0f%% ", ptotal);
1736 
1737 		(void) fprintf(out, "%4.2f %8s ",
1738 		    (double)lsp->ls_refcnt / lsp->ls_count, buf);
1739 
1740 		(void) fprintf(out, "%-22s ",
1741 		    format_symbol(buf, lsp->ls_lock, g_cflag));
1742 
1743 		(void) fprintf(out, "%-24s\n",
1744 		    format_symbol(buf, lsp->ls_caller, 0));
1745 
1746 		if (rectype < LS_HIST)
1747 			continue;
1748 
1749 		(void) fprintf(out, "\n");
1750 		(void) fprintf(out, "%10s %31s %-9s %-24s\n",
1751 			g_event_info[event].ev_units,
1752 			"------ Time Distribution ------",
1753 			g_rates ? "ops/s" : "count",
1754 			rectype > LS_STACK(0) ? "Stack" : "");
1755 
1756 		first_bin = 0;
1757 		while (lsp->ls_hist[first_bin] == 0)
1758 			first_bin++;
1759 
1760 		last_bin = 63;
1761 		while (lsp->ls_hist[last_bin] == 0)
1762 			last_bin--;
1763 
1764 		max_bin_count = 0;
1765 		total_bin_count = 0;
1766 		for (j = first_bin; j <= last_bin; j++) {
1767 			total_bin_count += lsp->ls_hist[j];
1768 			if (lsp->ls_hist[j] > max_bin_count)
1769 				max_bin_count = lsp->ls_hist[j];
1770 		}
1771 
1772 		/*
1773 		 * If we went a few frames below the caller, ignore them
1774 		 */
1775 		for (fr = 3; fr > 0; fr--)
1776 			if (lsp->ls_stack[fr] == lsp->ls_caller)
1777 				break;
1778 
1779 		for (j = first_bin; j <= last_bin; j++) {
1780 			uint_t depth = (lsp->ls_hist[j] * 30) / total_bin_count;
1781 			(void) fprintf(out, "%10llu |%s%s %-9u ",
1782 			    1ULL << j,
1783 			    "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@" + 30 - depth,
1784 			    "                              " + depth,
1785 			    g_rates == 0 ? lsp->ls_hist[j] :
1786 			    (uint_t)(((uint64_t)lsp->ls_hist[j] * NANOSEC) /
1787 			    g_elapsed));
1788 			if (rectype <= LS_STACK(fr) || lsp->ls_stack[fr] == 0) {
1789 				(void) fprintf(out, "\n");
1790 				continue;
1791 			}
1792 			(void) fprintf(out, "%-24s\n",
1793 			    format_symbol(buf, lsp->ls_stack[fr], 0));
1794 			fr++;
1795 		}
1796 		while (rectype > LS_STACK(fr) && lsp->ls_stack[fr] != 0) {
1797 			(void) fprintf(out, "%15s %-36s %-24s\n", "", "",
1798 			    format_symbol(buf, lsp->ls_stack[fr], 0));
1799 			fr++;
1800 		}
1801 	}
1802 
1803 	if (!g_pflag)
1804 		(void) fprintf(out, "---------------------------------"
1805 		    "----------------------------------------------\n");
1806 
1807 	(void) fflush(out);
1808 }
1809 
1810 static void
1811 report_trace(FILE *out, lsrec_t **sort_buf)
1812 {
1813 	lsrec_t *lsp;
1814 	int i, fr;
1815 	int rectype;
1816 	char buf[256], buf2[256];
1817 
1818 	rectype = g_recsize;
1819 
1820 	if (!g_pflag) {
1821 		(void) fprintf(out, "%5s  %7s  %11s  %-24s  %-24s\n",
1822 		    "Event", "Time", "Owner", "Lock", "Caller");
1823 		(void) fprintf(out, "---------------------------------"
1824 		    "----------------------------------------------\n");
1825 	}
1826 
1827 	for (i = 0; i < g_nrecs_used; i++) {
1828 
1829 		lsp = sort_buf[i];
1830 
1831 		if (lsp->ls_event >= LS_MAX_EVENTS || lsp->ls_count == 0)
1832 			continue;
1833 
1834 		(void) fprintf(out, "%2d  %10llu  %11p  %-24s  %-24s\n",
1835 		    lsp->ls_event, (unsigned long long)lsp->ls_time,
1836 		    (void *)lsp->ls_next,
1837 		    format_symbol(buf, lsp->ls_lock, 0),
1838 		    format_symbol(buf2, lsp->ls_caller, 0));
1839 
1840 		if (rectype <= LS_STACK(0))
1841 			continue;
1842 
1843 		/*
1844 		 * If we went a few frames below the caller, ignore them
1845 		 */
1846 		for (fr = 3; fr > 0; fr--)
1847 			if (lsp->ls_stack[fr] == lsp->ls_caller)
1848 				break;
1849 
1850 		while (rectype > LS_STACK(fr) && lsp->ls_stack[fr] != 0) {
1851 			(void) fprintf(out, "%53s  %-24s\n", "",
1852 			    format_symbol(buf, lsp->ls_stack[fr], 0));
1853 			fr++;
1854 		}
1855 		(void) fprintf(out, "\n");
1856 	}
1857 
1858 	(void) fflush(out);
1859 }
1860