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main.c revision 1.14.8.1 
      1 /*	$NetBSD: main.c,v 1.14.8.1 2009/05/13 19:20:28 jym Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2006, 2007, 2009 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Andrew Doran.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 __RCSID("$NetBSD: main.c,v 1.14.8.1 2009/05/13 19:20:28 jym Exp $");
     35 #endif /* not lint */
     36 
     37 #include <sys/types.h>
     38 #include <sys/param.h>
     39 #include <sys/time.h>
     40 #include <sys/fcntl.h>
     41 #include <sys/ioctl.h>
     42 #include <sys/wait.h>
     43 #include <sys/signal.h>
     44 #include <sys/sysctl.h>
     45 
     46 #include <dev/lockstat.h>
     47 
     48 #include <stdio.h>
     49 #include <stdlib.h>
     50 #include <string.h>
     51 #include <limits.h>
     52 #include <unistd.h>
     53 #include <err.h>
     54 #include <paths.h>
     55 #include <util.h>
     56 #include <ctype.h>
     57 #include <errno.h>
     58 #include <stdbool.h>
     59 
     60 #include "extern.h"
     61 
     62 #define	_PATH_DEV_LOCKSTAT	"/dev/lockstat"
     63 
     64 #define	MILLI	1000.0
     65 #define	MICRO	1000000.0
     66 #define	NANO	1000000000.0
     67 #define	PICO	1000000000000.0
     68 
     69 TAILQ_HEAD(lock_head, lockstruct);
     70 typedef struct lock_head locklist_t;
     71 TAILQ_HEAD(buf_head, lsbuf);
     72 typedef struct buf_head buflist_t;
     73 
     74 typedef struct lockstruct {
     75 	TAILQ_ENTRY(lockstruct)	chain;
     76 	buflist_t		bufs;
     77 	buflist_t		tosort;
     78 	uintptr_t		lock;
     79  	double			time;
     80 	uint32_t		count;
     81 	u_int			flags;
     82 	u_int			nbufs;
     83 	char			name[NAME_SIZE];
     84 } lock_t;
     85 
     86 typedef struct name {
     87 	const char	*name;
     88 	int		mask;
     89 } name_t;
     90 
     91 const name_t locknames[] = {
     92 	{ "adaptive_mutex", LB_ADAPTIVE_MUTEX },
     93 	{ "spin_mutex", LB_SPIN_MUTEX },
     94 	{ "rwlock", LB_RWLOCK },
     95 	{ "kernel_lock", LB_KERNEL_LOCK },
     96 	{ "preemption", LB_NOPREEMPT },
     97 	{ "misc", LB_MISC },
     98 	{ NULL, 0 }
     99 };
    100 
    101 const name_t eventnames[] = {
    102 	{ "spin", LB_SPIN },
    103 	{ "sleep_exclusive", LB_SLEEP1 },
    104 	{ "sleep_shared", LB_SLEEP2 },
    105 	{ NULL, 0 },
    106 };
    107 
    108 const name_t alltypes[] = {
    109 	{ "Adaptive mutex spin", LB_ADAPTIVE_MUTEX | LB_SPIN },
    110 	{ "Adaptive mutex sleep", LB_ADAPTIVE_MUTEX | LB_SLEEP1 },
    111 	{ "Spin mutex spin", LB_SPIN_MUTEX | LB_SPIN },
    112 	{ "RW lock sleep (writer)", LB_RWLOCK | LB_SLEEP1 },
    113 	{ "RW lock sleep (reader)", LB_RWLOCK | LB_SLEEP2 },
    114 	{ "RW lock spin", LB_RWLOCK | LB_SPIN },
    115 	{ "Kernel lock spin", LB_KERNEL_LOCK | LB_SPIN },
    116 	{ "Kernel preemption defer", LB_NOPREEMPT | LB_SPIN },
    117 	{ "Miscellaneous wait", LB_MISC | LB_SPIN },
    118 	{ NULL, 0 }
    119 };
    120 
    121 const name_t xtypes[] = {
    122 	{ "Spin", LB_SPIN },
    123 	{ "Sleep (writer)", LB_SLEEP1 },
    124 	{ "Sleep (reader)", LB_SLEEP2 },
    125 	{ NULL, 0 }
    126 };
    127 
    128 locklist_t	locklist;
    129 locklist_t	freelist;
    130 locklist_t	sortlist;
    131 
    132 lsbuf_t		*bufs;
    133 lsdisable_t	ld;
    134 bool		lflag;
    135 bool		fflag;
    136 int		nbufs;
    137 bool		cflag;
    138 bool		xflag;
    139 int		lsfd;
    140 int		displayed;
    141 int		bin64;
    142 double		tscale;
    143 double		cscale;
    144 double		cpuscale[sizeof(ld.ld_freq) / sizeof(ld.ld_freq[0])];
    145 FILE		*outfp;
    146 
    147 void	findsym(findsym_t, char *, uintptr_t *, uintptr_t *, bool);
    148 void	spawn(int, char **);
    149 void	display(int, const char *name);
    150 void	listnames(const name_t *);
    151 void	collapse(bool, bool);
    152 int	matchname(const name_t *, char *);
    153 void	makelists(int, int);
    154 void	nullsig(int);
    155 void	usage(void);
    156 int	ncpu(void);
    157 lock_t	*morelocks(void);
    158 
    159 int
    160 main(int argc, char **argv)
    161 {
    162 	int eventtype, locktype, ch, nlfd, fd;
    163 	size_t i;
    164 	bool sflag, pflag, mflag, Mflag;
    165 	const char *nlistf, *outf;
    166 	char *lockname, *funcname;
    167 	const name_t *name;
    168 	lsenable_t le;
    169 	double ms;
    170 	char *p;
    171 
    172 	nlistf = NULL;
    173 	outf = NULL;
    174 	lockname = NULL;
    175 	funcname = NULL;
    176 	eventtype = -1;
    177 	locktype = -1;
    178 	nbufs = 0;
    179 	sflag = false;
    180 	pflag = false;
    181 	mflag = false;
    182 	Mflag = false;
    183 
    184 	while ((ch = getopt(argc, argv, "E:F:L:MN:T:b:ceflmo:pstx")) != -1)
    185 		switch (ch) {
    186 		case 'E':
    187 			eventtype = matchname(eventnames, optarg);
    188 			break;
    189 		case 'F':
    190 			funcname = optarg;
    191 			break;
    192 		case 'L':
    193 			lockname = optarg;
    194 			break;
    195 		case 'N':
    196 			nlistf = optarg;
    197 			break;
    198 		case 'T':
    199 			locktype = matchname(locknames, optarg);
    200 			break;
    201 		case 'b':
    202 			nbufs = (int)strtol(optarg, &p, 0);
    203 			if (!isdigit((u_int)*optarg) || *p != '\0')
    204 				usage();
    205 			break;
    206 		case 'c':
    207 			cflag = true;
    208 			break;
    209 		case 'e':
    210 			listnames(eventnames);
    211 			break;
    212 		case 'f':
    213 			fflag = true;
    214 			break;
    215 		case 'l':
    216 			lflag = true;
    217 			break;
    218 		case 'm':
    219 			mflag = true;
    220 			break;
    221 		case 'M':
    222 			Mflag = true;
    223 			break;
    224 		case 'o':
    225 			outf = optarg;
    226 			break;
    227 		case 'p':
    228 			pflag = true;
    229 			break;
    230 		case 's':
    231 			sflag = true;
    232 			break;
    233 		case 't':
    234 			listnames(locknames);
    235 			break;
    236 		case 'x':
    237 			xflag = true;
    238 			break;
    239 		default:
    240 			usage();
    241 		}
    242 	argc -= optind;
    243 	argv += optind;
    244 
    245 	if (*argv == NULL)
    246 		usage();
    247 
    248 	if (outf) {
    249 		fd = open(outf, O_WRONLY | O_CREAT | O_TRUNC, 0600);
    250 		if (fd == -1)
    251 			err(EXIT_FAILURE, "opening %s", outf);
    252 		outfp = fdopen(fd, "w");
    253 	} else
    254 		outfp = stdout;
    255 
    256 	/*
    257 	 * Find the name list for resolving symbol names, and load it into
    258 	 * memory.
    259 	 */
    260 	if (nlistf == NULL) {
    261 		nlfd = open(_PATH_KSYMS, O_RDONLY);
    262 		nlistf = getbootfile();
    263 	} else
    264 		nlfd = -1;
    265 	if (nlfd == -1) {
    266 		if ((nlfd = open(nlistf, O_RDONLY)) < 0)
    267 			err(EXIT_FAILURE, "cannot open " _PATH_KSYMS " or %s",
    268 			    nlistf);
    269 	}
    270 	if (loadsym32(nlfd) != 0) {
    271 		if (loadsym64(nlfd) != 0)
    272 			errx(EXIT_FAILURE, "unable to load symbol table");
    273 		bin64 = 1;
    274 	}
    275 	close(nlfd);
    276 
    277 	memset(&le, 0, sizeof(le));
    278 	le.le_nbufs = nbufs;
    279 
    280 	/*
    281 	 * Set up initial filtering.
    282 	 */
    283 	if (lockname != NULL) {
    284 		findsym(LOCK_BYNAME, lockname, &le.le_lockstart,
    285 		    &le.le_lockend, true);
    286 		le.le_flags |= LE_ONE_LOCK;
    287 	}
    288 	if (!lflag)
    289 		le.le_flags |= LE_CALLSITE;
    290 	if (!fflag)
    291 		le.le_flags |= LE_LOCK;
    292 	if (funcname != NULL) {
    293 		if (lflag)
    294 			usage();
    295 		findsym(FUNC_BYNAME, funcname, &le.le_csstart, &le.le_csend, true);
    296 		le.le_flags |= LE_ONE_CALLSITE;
    297 	}
    298 	le.le_mask = (eventtype & LB_EVENT_MASK) | (locktype & LB_LOCK_MASK);
    299 
    300 	/*
    301 	 * Start tracing.
    302 	 */
    303 	if ((lsfd = open(_PATH_DEV_LOCKSTAT, O_RDONLY)) < 0)
    304 		err(EXIT_FAILURE, "cannot open " _PATH_DEV_LOCKSTAT);
    305 	if (ioctl(lsfd, IOC_LOCKSTAT_GVERSION, &ch) < 0)
    306 		err(EXIT_FAILURE, "ioctl");
    307 	if (ch != LS_VERSION)
    308 		errx(EXIT_FAILURE,
    309 		    "incompatible lockstat interface version (%d, kernel %d)",
    310 			LS_VERSION, ch);
    311 	if (ioctl(lsfd, IOC_LOCKSTAT_ENABLE, &le))
    312 		err(EXIT_FAILURE, "cannot enable tracing");
    313 
    314 	/*
    315 	 * Execute the traced program.
    316 	 */
    317 	spawn(argc, argv);
    318 
    319 	/*
    320 	 * Stop tracing, and read the trace buffers from the kernel.
    321 	 */
    322 	if (ioctl(lsfd, IOC_LOCKSTAT_DISABLE, &ld) == -1) {
    323 		if (errno == EOVERFLOW) {
    324 			warnx("overflowed available kernel trace buffers");
    325 			exit(EXIT_FAILURE);
    326 		}
    327 		err(EXIT_FAILURE, "cannot disable tracing");
    328 	}
    329 	if ((bufs = malloc(ld.ld_size)) == NULL)
    330 		err(EXIT_FAILURE, "cannot allocate memory for user buffers");
    331 	if ((size_t)read(lsfd, bufs, ld.ld_size) != ld.ld_size)
    332 		err(EXIT_FAILURE, "reading from " _PATH_DEV_LOCKSTAT);
    333 	if (close(lsfd))
    334 		err(EXIT_FAILURE, "close(" _PATH_DEV_LOCKSTAT ")");
    335 
    336 	/*
    337 	 * Figure out how to scale the results.  For internal use we convert
    338 	 * all times from CPU frequency based to picoseconds, and values are
    339 	 * eventually displayed in ms.
    340 	 */
    341 	for (i = 0; i < sizeof(ld.ld_freq) / sizeof(ld.ld_freq[0]); i++)
    342 		if (ld.ld_freq[i] != 0)
    343 			cpuscale[i] = PICO / ld.ld_freq[i];
    344 	ms = ld.ld_time.tv_sec * MILLI + ld.ld_time.tv_nsec / MICRO;
    345 	if (pflag)
    346 		cscale = 1.0 / ncpu();
    347 	else
    348 		cscale = 1.0;
    349 	cscale *= (sflag ? MILLI / ms : 1.0);
    350 	tscale = cscale / NANO;
    351 	nbufs = (int)(ld.ld_size / sizeof(lsbuf_t));
    352 
    353 	TAILQ_INIT(&locklist);
    354 	TAILQ_INIT(&sortlist);
    355 	TAILQ_INIT(&freelist);
    356 
    357 	if ((mflag | Mflag) != 0)
    358 		collapse(mflag, Mflag);
    359 
    360 	/*
    361 	 * Display the results.
    362 	 */
    363 	fprintf(outfp, "Elapsed time: %.2f seconds.", ms / MILLI);
    364 	if (sflag || pflag) {
    365 		fprintf(outfp, " Displaying ");
    366 		if (pflag)
    367 			fprintf(outfp, "per-CPU ");
    368 		if (sflag)
    369 			fprintf(outfp, "per-second ");
    370 		fprintf(outfp, "averages.");
    371 	}
    372 	putc('\n', outfp);
    373 
    374 	for (name = xflag ? xtypes : alltypes; name->name != NULL; name++) {
    375 		if (eventtype != -1 &&
    376 		    (name->mask & LB_EVENT_MASK) != eventtype)
    377 			continue;
    378 		if (locktype != -1 &&
    379 		    (name->mask & LB_LOCK_MASK) != locktype)
    380 			continue;
    381 		display(name->mask, name->name);
    382 	}
    383 
    384 	if (displayed == 0)
    385 		fprintf(outfp, "None of the selected events were recorded.\n");
    386 	exit(EXIT_SUCCESS);
    387 }
    388 
    389 void
    390 usage(void)
    391 {
    392 
    393 	fprintf(stderr,
    394 	    "%s: usage:\n"
    395 	    "%s [options] <command>\n\n"
    396 	    "-b nbuf\t\tset number of event buffers to allocate\n"
    397 	    "-c\t\treport percentage of total events by count, not time\n"
    398 	    "-E event\t\tdisplay only one type of event\n"
    399 	    "-e\t\tlist event types\n"
    400 	    "-F func\t\tlimit trace to one function\n"
    401 	    "-f\t\ttrace only by function\n"
    402 	    "-L lock\t\tlimit trace to one lock (name, or address)\n"
    403 	    "-l\t\ttrace only by lock\n"
    404 	    "-M\t\tmerge lock addresses within unique objects\n"
    405 	    "-m\t\tmerge call sites within unique functions\n"
    406 	    "-N nlist\tspecify name list file\n"
    407 	    "-o file\t\tsend output to named file, not stdout\n"
    408 	    "-p\t\tshow average count/time per CPU, not total\n"
    409 	    "-s\t\tshow average count/time per second, not total\n"
    410 	    "-T type\t\tdisplay only one type of lock\n"
    411 	    "-t\t\tlist lock types\n"
    412 	    "-x\t\tdon't differentiate event types\n",
    413 	    getprogname(), getprogname());
    414 
    415 	exit(EXIT_FAILURE);
    416 }
    417 
    418 void
    419 nullsig(int junk)
    420 {
    421 
    422 	(void)junk;
    423 }
    424 
    425 void
    426 listnames(const name_t *name)
    427 {
    428 
    429 	for (; name->name != NULL; name++)
    430 		printf("%s\n", name->name);
    431 
    432 	exit(EXIT_SUCCESS);
    433 }
    434 
    435 int
    436 matchname(const name_t *name, char *string)
    437 {
    438 	int empty, mask;
    439 	char *sp;
    440 
    441 	empty = 1;
    442 	mask = 0;
    443 
    444 	while ((sp = strsep(&string, ",")) != NULL) {
    445 		if (*sp == '\0')
    446 			usage();
    447 
    448 		for (; name->name != NULL; name++) {
    449 			if (strcasecmp(name->name, sp) == 0) {
    450 				mask |= name->mask;
    451 				break;
    452 			}
    453 		}
    454 		if (name->name == NULL)
    455 			errx(EXIT_FAILURE, "unknown identifier `%s'", sp);
    456 		empty = 0;
    457 	}
    458 
    459 	if (empty)
    460 		usage();
    461 
    462 	return mask;
    463 }
    464 
    465 /*
    466  * Return the number of CPUs in the running system.
    467  */
    468 int
    469 ncpu(void)
    470 {
    471 	int rv, mib[2];
    472 	size_t varlen;
    473 
    474 	mib[0] = CTL_HW;
    475 	mib[1] = HW_NCPU;
    476 	varlen = sizeof(rv);
    477 	if (sysctl(mib, 2, &rv, &varlen, NULL, (size_t)0) < 0)
    478 		rv = 1;
    479 
    480 	return (rv);
    481 }
    482 
    483 /*
    484  * Call into the ELF parser and look up a symbol by name or by address.
    485  */
    486 void
    487 findsym(findsym_t find, char *name, uintptr_t *start, uintptr_t *end, bool chg)
    488 {
    489 	uintptr_t tend, sa, ea;
    490 	char *p;
    491 	int rv;
    492 
    493 	if (!chg) {
    494 		sa = *start;
    495 		start = &sa;
    496 		end = &ea;
    497 	}
    498 
    499 	if (end == NULL)
    500 		end = &tend;
    501 
    502 	if (find == LOCK_BYNAME) {
    503 		if (isdigit((u_int)name[0])) {
    504 			*start = (uintptr_t)strtoul(name, &p, 0);
    505 			if (*p == '\0')
    506 				return;
    507 		}
    508 	}
    509 
    510 	if (bin64)
    511 		rv = findsym64(find, name, start, end);
    512 	else
    513 		rv = findsym32(find, name, start, end);
    514 
    515 	if (find == FUNC_BYNAME || find == LOCK_BYNAME) {
    516 		if (rv == -1)
    517 			errx(EXIT_FAILURE, "unable to find symbol `%s'", name);
    518 		return;
    519 	}
    520 
    521 	if (rv == -1)
    522 		snprintf(name, NAME_SIZE, "%016lx", (long)*start);
    523 }
    524 
    525 /*
    526  * Fork off the child process and wait for it to complete.  We trap SIGINT
    527  * so that the caller can use Ctrl-C to stop tracing early and still get
    528  * useful results.
    529  */
    530 void
    531 spawn(int argc, char **argv)
    532 {
    533 	pid_t pid;
    534 
    535 	switch (pid = fork()) {
    536 	case 0:
    537 		close(lsfd);
    538 		if (execvp(argv[0], argv) == -1)
    539 			err(EXIT_FAILURE, "cannot exec");
    540 		break;
    541 	case -1:
    542 		err(EXIT_FAILURE, "cannot fork to exec");
    543 		break;
    544 	default:
    545 		signal(SIGINT, nullsig);
    546 		wait(NULL);
    547 		signal(SIGINT, SIG_DFL);
    548 		break;
    549 	}
    550 }
    551 
    552 /*
    553  * Allocate a new block of lock_t structures.
    554  */
    555 lock_t *
    556 morelocks(void)
    557 {
    558 	const int batch = 32;
    559 	lock_t *l, *lp, *max;
    560 
    561 	l = (lock_t *)malloc(sizeof(*l) * batch);
    562 
    563 	for (lp = l, max = l + batch; lp < max; lp++)
    564 		TAILQ_INSERT_TAIL(&freelist, lp, chain);
    565 
    566 	return l;
    567 }
    568 
    569 /*
    570  * Collapse addresses from unique objects.
    571  */
    572 void
    573 collapse(bool func, bool lock)
    574 {
    575 	lsbuf_t *lb, *max;
    576 
    577 	for (lb = bufs, max = bufs + nbufs; lb < max; lb++) {
    578 		if (func && lb->lb_callsite != 0) {
    579 			findsym(FUNC_BYADDR, NULL, &lb->lb_callsite, NULL,
    580 			    true);
    581 		}
    582 		if (lock && lb->lb_lock != 0) {
    583 			findsym(LOCK_BYADDR, NULL, &lb->lb_lock, NULL,
    584 			    true);
    585 		}
    586 	}
    587 }
    588 
    589 /*
    590  * From the kernel supplied data, construct two dimensional lists of locks
    591  * and event buffers, indexed by lock type and sorted by event type.
    592  */
    593 void
    594 makelists(int mask, int event)
    595 {
    596 	lsbuf_t *lb, *lb2, *max;
    597 	lock_t *l, *l2;
    598 	int type;
    599 
    600 	/*
    601 	 * Recycle lock_t structures from the last run.
    602 	 */
    603 	while ((l = TAILQ_FIRST(&locklist)) != NULL) {
    604 		TAILQ_REMOVE(&locklist, l, chain);
    605 		TAILQ_INSERT_HEAD(&freelist, l, chain);
    606 	}
    607 
    608 	type = mask & LB_LOCK_MASK;
    609 
    610 	for (lb = bufs, max = bufs + nbufs; lb < max; lb++) {
    611 		if (!xflag && (lb->lb_flags & LB_LOCK_MASK) != type)
    612 			continue;
    613 		if (lb->lb_counts[event] == 0)
    614 			continue;
    615 
    616 		/*
    617 		 * Look for a record descibing this lock, and allocate a
    618 		 * new one if needed.
    619 		 */
    620 		TAILQ_FOREACH(l, &sortlist, chain) {
    621 			if (l->lock == lb->lb_lock)
    622 				break;
    623 		}
    624 		if (l == NULL) {
    625 			if ((l = TAILQ_FIRST(&freelist)) == NULL)
    626 				l = morelocks();
    627 			TAILQ_REMOVE(&freelist, l, chain);
    628 			l->flags = lb->lb_flags;
    629 			l->lock = lb->lb_lock;
    630 			l->nbufs = 0;
    631 			l->name[0] = '\0';
    632 			l->count = 0;
    633 			l->time = 0;
    634 			TAILQ_INIT(&l->tosort);
    635 			TAILQ_INIT(&l->bufs);
    636 			TAILQ_INSERT_TAIL(&sortlist, l, chain);
    637 		}
    638 
    639 		/*
    640 		 * Scale the time values per buffer and summarise
    641 		 * times+counts per lock.
    642 		 */
    643 		lb->lb_times[event] *= cpuscale[lb->lb_cpu];
    644 		l->count += lb->lb_counts[event];
    645 		l->time += lb->lb_times[event];
    646 
    647 		/*
    648 		 * Merge same lock+callsite pairs from multiple CPUs
    649 		 * together.
    650 		 */
    651 		TAILQ_FOREACH(lb2, &l->tosort, lb_chain.tailq) {
    652 			if (lb->lb_callsite == lb2->lb_callsite)
    653 				break;
    654 		}
    655 		if (lb2 != NULL) {
    656 			lb2->lb_counts[event] += lb->lb_counts[event];
    657 			lb2->lb_times[event] += lb->lb_times[event];
    658 		} else {
    659 			TAILQ_INSERT_HEAD(&l->tosort, lb, lb_chain.tailq);
    660 			l->nbufs++;
    661 		}
    662 	}
    663 
    664 	/*
    665 	 * Now sort the lists.
    666 	 */
    667 	while ((l = TAILQ_FIRST(&sortlist)) != NULL) {
    668 		TAILQ_REMOVE(&sortlist, l, chain);
    669 
    670 		/*
    671 		 * Sort the buffers into the per-lock list.
    672 		 */
    673 		while ((lb = TAILQ_FIRST(&l->tosort)) != NULL) {
    674 			TAILQ_REMOVE(&l->tosort, lb, lb_chain.tailq);
    675 
    676 			lb2 = TAILQ_FIRST(&l->bufs);
    677 			while (lb2 != NULL) {
    678 				if (cflag) {
    679 					if (lb->lb_counts[event] >
    680 					    lb2->lb_counts[event])
    681 						break;
    682 				} else if (lb->lb_times[event] >
    683 				    lb2->lb_times[event])
    684 					break;
    685 				lb2 = TAILQ_NEXT(lb2, lb_chain.tailq);
    686 			}
    687 			if (lb2 == NULL)
    688 				TAILQ_INSERT_TAIL(&l->bufs, lb,
    689 				    lb_chain.tailq);
    690 			else
    691 				TAILQ_INSERT_BEFORE(lb2, lb, lb_chain.tailq);
    692 		}
    693 
    694 		/*
    695 		 * Sort this lock into the per-type list, based on the
    696 		 * totals per lock.
    697 		 */
    698 		l2 = TAILQ_FIRST(&locklist);
    699 		while (l2 != NULL) {
    700 			if (cflag) {
    701 				if (l->count > l2->count)
    702 					break;
    703 			} else if (l->time > l2->time)
    704 				break;
    705 			l2 = TAILQ_NEXT(l2, chain);
    706 		}
    707 		if (l2 == NULL)
    708 			TAILQ_INSERT_TAIL(&locklist, l, chain);
    709 		else
    710 			TAILQ_INSERT_BEFORE(l2, l, chain);
    711 	}
    712 }
    713 
    714 /*
    715  * Display a summary table for one lock type / event type pair.
    716  */
    717 void
    718 display(int mask, const char *name)
    719 {
    720 	lock_t *l;
    721 	lsbuf_t *lb;
    722 	double pcscale, metric;
    723 	char fname[NAME_SIZE];
    724 	int event;
    725 
    726 	event = (mask & LB_EVENT_MASK) - 1;
    727 	makelists(mask, event);
    728 
    729 	if (TAILQ_EMPTY(&locklist))
    730 		return;
    731 
    732 	fprintf(outfp, "\n-- %s\n\n"
    733 	    "Total%%  Count   Time/ms          Lock                       Caller\n"
    734 	    "------ ------- --------- ---------------------- ------------------------------\n",
    735 	    name);
    736 
    737 	/*
    738 	 * Sum up all events for this type of lock + event.
    739 	 */
    740 	pcscale = 0;
    741 	TAILQ_FOREACH(l, &locklist, chain) {
    742 		if (cflag)
    743 			pcscale += l->count;
    744 		else
    745 			pcscale += l->time;
    746 		displayed++;
    747 	}
    748 	if (pcscale == 0)
    749 		pcscale = 100;
    750 	else
    751 		pcscale = (100.0 / pcscale);
    752 
    753 	/*
    754 	 * For each lock, print a summary total, followed by a breakdown by
    755 	 * caller.
    756 	 */
    757 	TAILQ_FOREACH(l, &locklist, chain) {
    758 		if (cflag)
    759 			metric = l->count;
    760 		else
    761 			metric = l->time;
    762 		metric *= pcscale;
    763 
    764 		if (l->name[0] == '\0')
    765 			findsym(LOCK_BYADDR, l->name, &l->lock, NULL, false);
    766 
    767 		if (lflag || l->nbufs > 1)
    768 			fprintf(outfp, "%6.2f %7d %9.2f %-22s <all>\n",
    769 			    metric, (int)(l->count * cscale),
    770 			    l->time * tscale, l->name);
    771 
    772 		if (lflag)
    773 			continue;
    774 
    775 		TAILQ_FOREACH(lb, &l->bufs, lb_chain.tailq) {
    776 			if (cflag)
    777 				metric = lb->lb_counts[event];
    778 			else
    779 				metric = lb->lb_times[event];
    780 			metric *= pcscale;
    781 
    782 			findsym(FUNC_BYADDR, fname, &lb->lb_callsite, NULL,
    783 			    false);
    784 			fprintf(outfp, "%6.2f %7d %9.2f %-22s %s\n",
    785 			    metric, (int)(lb->lb_counts[event] * cscale),
    786 			    lb->lb_times[event] * tscale, l->name, fname);
    787 		}
    788 	}
    789 }
    790