1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2005-2007, Joseph Koshy
5 * Copyright (c) 2007 The FreeBSD Foundation
6 * Copyright (c) 2009, Fabien Thomas
7 * All rights reserved.
8 *
9 * Portions of this software were developed by A. Joseph Koshy under
10 * sponsorship from the FreeBSD Foundation and Google, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34/*
35 * Transform a hwpmc(4) log into human readable form, and into
36 * gprof(1) compatible profiles.
37 */
38
39#include <sys/cdefs.h>
40__FBSDID("$FreeBSD$");
41
42#include <sys/param.h>
43#include <sys/endian.h>
44#include <sys/gmon.h>
45#include <sys/imgact_aout.h>
46#include <sys/imgact_elf.h>
47#include <sys/mman.h>
48#include <sys/pmc.h>
49#include <sys/queue.h>
50#include <sys/socket.h>
51#include <sys/stat.h>
52#include <sys/wait.h>
53
54#include <netinet/in.h>
55
56#include <assert.h>
57#include <curses.h>
58#include <err.h>
59#include <errno.h>
60#include <fcntl.h>
61#include <gelf.h>
62#include <libgen.h>
63#include <limits.h>
64#include <netdb.h>
65#include <pmc.h>
66#include <pmclog.h>
67#include <sysexits.h>
68#include <stdint.h>
69#include <stdio.h>
70#include <stdlib.h>
71#include <string.h>
72#include <unistd.h>
73
74#include "pmcstat.h"
75#include "pmcstat_log.h"
76#include "pmcpl_callgraph.h"
77#include "pmcpl_gprof.h"
78
79typedef	uint64_t	WIDEHISTCOUNTER;
80
81#define	min(A,B)		((A) < (B) ? (A) : (B))
82#define	max(A,B)		((A) > (B) ? (A) : (B))
83
84#define	WIDEHISTCOUNTER_MAX		UINT64_MAX
85#define	HISTCOUNTER_MAX			USHRT_MAX
86#define	WIDEHISTCOUNTER_GMONTYPE	((int) 64)
87#define	HISTCOUNTER_GMONTYPE		((int) 0)
88static int hc_sz=0;
89
90/*
91 * struct pmcstat_gmonfile tracks a given 'gmon.out' file.  These
92 * files are mmap()'ed in as needed.
93 */
94
95struct pmcstat_gmonfile {
96	LIST_ENTRY(pmcstat_gmonfile)	pgf_next; /* list of entries */
97	int		pgf_overflow;	/* whether a count overflowed */
98	pmc_id_t	pgf_pmcid;	/* id of the associated pmc */
99	size_t		pgf_nbuckets;	/* #buckets in this gmon.out */
100	unsigned int	pgf_nsamples;	/* #samples in this gmon.out */
101	pmcstat_interned_string pgf_name;	/* pathname of gmon.out file */
102	size_t		pgf_ndatabytes;	/* number of bytes mapped */
103	void		*pgf_gmondata;	/* pointer to mmap'ed data */
104	FILE		*pgf_file;	/* used when writing gmon arcs */
105};
106
107/*
108 * Prototypes
109 */
110
111static void	pmcstat_gmon_create_file(struct pmcstat_gmonfile *_pgf,
112    struct pmcstat_image *_image);
113static pmcstat_interned_string pmcstat_gmon_create_name(const char *_sd,
114    struct pmcstat_image *_img, pmc_id_t _pmcid);
115static void	pmcstat_gmon_map_file(struct pmcstat_gmonfile *_pgf);
116static void	pmcstat_gmon_unmap_file(struct pmcstat_gmonfile *_pgf);
117
118static struct pmcstat_gmonfile *pmcstat_image_find_gmonfile(struct
119    pmcstat_image *_i, pmc_id_t _id);
120
121/*
122 * Create a gmon.out file and size it.
123 */
124
125static void
126pmcstat_gmon_create_file(struct pmcstat_gmonfile *pgf,
127    struct pmcstat_image *image)
128{
129	int fd;
130	size_t count;
131	struct gmonhdr gm;
132	const char *pathname;
133	char buffer[DEFAULT_BUFFER_SIZE];
134
135	pathname = pmcstat_string_unintern(pgf->pgf_name);
136	if ((fd = open(pathname, O_RDWR|O_NOFOLLOW|O_CREAT,
137		 S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)) < 0)
138		err(EX_OSERR, "ERROR: Cannot open \"%s\"", pathname);
139
140	gm.lpc = image->pi_start;
141	gm.hpc = image->pi_end;
142	gm.ncnt = (pgf->pgf_nbuckets * hc_sz) + sizeof(struct gmonhdr);
143	gm.version = GMONVERSION;
144	gm.profrate = 0;		/* use ticks */
145	if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC)
146		gm.histcounter_type = WIDEHISTCOUNTER_GMONTYPE;
147	else
148		gm.histcounter_type = HISTCOUNTER_GMONTYPE;
149	gm.spare[0] = gm.spare[1] = 0;
150
151	/* Write out the gmon header */
152	if (write(fd, &gm, sizeof(gm)) < 0)
153		goto error;
154
155	/* Zero fill the samples[] array */
156	(void) memset(buffer, 0, sizeof(buffer));
157
158	count = pgf->pgf_ndatabytes - sizeof(struct gmonhdr);
159	while (count > sizeof(buffer)) {
160		if (write(fd, &buffer, sizeof(buffer)) < 0)
161			goto error;
162		count -= sizeof(buffer);
163	}
164
165	if (write(fd, &buffer, count) < 0)
166		goto error;
167
168	(void) close(fd);
169
170	return;
171
172 error:
173	err(EX_OSERR, "ERROR: Cannot write \"%s\"", pathname);
174}
175
176/*
177 * Determine the full pathname of a gmon.out file for a given
178 * (image,pmcid) combination.  Return the interned string.
179 */
180
181pmcstat_interned_string
182pmcstat_gmon_create_name(const char *samplesdir, struct pmcstat_image *image,
183    pmc_id_t pmcid)
184{
185	const char *pmcname;
186	char fullpath[PATH_MAX];
187
188	pmcname = pmcstat_pmcid_to_name(pmcid);
189	if (!pmcname)
190		err(EX_SOFTWARE, "ERROR: cannot find pmcid");
191
192	(void) snprintf(fullpath, sizeof(fullpath),
193	    "%s/%s/%s", samplesdir, pmcname,
194	    pmcstat_string_unintern(image->pi_samplename));
195
196	return (pmcstat_string_intern(fullpath));
197}
198
199
200/*
201 * Mmap in a gmon.out file for processing.
202 */
203
204static void
205pmcstat_gmon_map_file(struct pmcstat_gmonfile *pgf)
206{
207	int fd;
208	const char *pathname;
209
210	pathname = pmcstat_string_unintern(pgf->pgf_name);
211
212	/* the gmon.out file must already exist */
213	if ((fd = open(pathname, O_RDWR | O_NOFOLLOW, 0)) < 0)
214		err(EX_OSERR, "ERROR: cannot open \"%s\"", pathname);
215
216	pgf->pgf_gmondata = mmap(NULL, pgf->pgf_ndatabytes,
217	    PROT_READ|PROT_WRITE, MAP_NOSYNC|MAP_SHARED, fd, 0);
218
219	if (pgf->pgf_gmondata == MAP_FAILED)
220		err(EX_OSERR, "ERROR: cannot map \"%s\"", pathname);
221
222	(void) close(fd);
223}
224
225/*
226 * Unmap a gmon.out file after sync'ing its data to disk.
227 */
228
229static void
230pmcstat_gmon_unmap_file(struct pmcstat_gmonfile *pgf)
231{
232	(void) msync(pgf->pgf_gmondata, pgf->pgf_ndatabytes,
233	    MS_SYNC);
234	(void) munmap(pgf->pgf_gmondata, pgf->pgf_ndatabytes);
235	pgf->pgf_gmondata = NULL;
236}
237
238static void
239pmcstat_gmon_append_arc(struct pmcstat_image *image, pmc_id_t pmcid,
240    uintptr_t rawfrom, uintptr_t rawto, uint32_t count)
241{
242	struct rawarc arc;	/* from <sys/gmon.h> */
243	const char *pathname;
244	struct pmcstat_gmonfile *pgf;
245
246	if ((pgf = pmcstat_image_find_gmonfile(image, pmcid)) == NULL)
247		return;
248
249	if (pgf->pgf_file == NULL) {
250		pathname = pmcstat_string_unintern(pgf->pgf_name);
251		if ((pgf->pgf_file = fopen(pathname, "a")) == NULL)
252			return;
253	}
254
255	arc.raw_frompc = rawfrom + image->pi_vaddr;
256	arc.raw_selfpc = rawto + image->pi_vaddr;
257	arc.raw_count = count;
258
259	(void) fwrite(&arc, sizeof(arc), 1, pgf->pgf_file);
260
261}
262
263static struct pmcstat_gmonfile *
264pmcstat_image_find_gmonfile(struct pmcstat_image *image, pmc_id_t pmcid)
265{
266	struct pmcstat_gmonfile *pgf;
267	LIST_FOREACH(pgf, &image->pi_gmlist, pgf_next)
268	    if (pgf->pgf_pmcid == pmcid)
269		    return (pgf);
270	return (NULL);
271}
272
273static void
274pmcstat_cgnode_do_gmon_arcs(struct pmcstat_cgnode *cg, pmc_id_t pmcid)
275{
276	struct pmcstat_cgnode *cgc;
277
278	/*
279	 * Look for child nodes that belong to the same image.
280	 */
281
282	LIST_FOREACH(cgc, &cg->pcg_children, pcg_sibling) {
283		if (cgc->pcg_image == cg->pcg_image)
284			pmcstat_gmon_append_arc(cg->pcg_image, pmcid,
285			    cgc->pcg_func, cg->pcg_func, cgc->pcg_count);
286		if (cgc->pcg_nchildren > 0)
287			pmcstat_cgnode_do_gmon_arcs(cgc, pmcid);
288	}
289}
290
291static void
292pmcstat_callgraph_do_gmon_arcs_for_pmcid(pmc_id_t pmcid)
293{
294	int n;
295	struct pmcstat_cgnode_hash *pch;
296
297	for (n = 0; n < PMCSTAT_NHASH; n++)
298		LIST_FOREACH(pch, &pmcstat_cgnode_hash[n], pch_next)
299			if (pch->pch_pmcid == pmcid &&
300			    pch->pch_cgnode->pcg_nchildren > 1)
301				pmcstat_cgnode_do_gmon_arcs(pch->pch_cgnode,
302				    pmcid);
303}
304
305
306static void
307pmcstat_callgraph_do_gmon_arcs(void)
308{
309	struct pmcstat_pmcrecord *pmcr;
310
311	LIST_FOREACH(pmcr, &pmcstat_pmcs, pr_next)
312		pmcstat_callgraph_do_gmon_arcs_for_pmcid(pmcr->pr_pmcid);
313}
314
315void
316pmcpl_gmon_initimage(struct pmcstat_image *pi)
317{
318	const char *execpath;
319	int count, nlen;
320	char *sn, *snbuf;
321	char name[NAME_MAX];
322
323	/*
324	 * Look for a suitable name for the sample files associated
325	 * with this image: if `basename(path)`+".gmon" is available,
326	 * we use that, otherwise we try iterating through
327	 * `basename(path)`+ "~" + NNN + ".gmon" till we get a free
328	 * entry.
329	 */
330	execpath = pmcstat_string_unintern(pi->pi_execpath);
331	if ((snbuf = strdup(execpath)) == NULL)
332		err(EX_OSERR, "ERROR: Cannot copy \"%s\"", execpath);
333	if ((sn = basename(snbuf)) == NULL)
334		err(EX_OSERR, "ERROR: Cannot process \"%s\"", execpath);
335
336	nlen = strlen(sn);
337	nlen = min(nlen, (int) (sizeof(name) - sizeof(".gmon")));
338
339	snprintf(name, sizeof(name), "%.*s.gmon", nlen, sn);
340
341	/* try use the unabridged name first */
342	if (pmcstat_string_lookup(name) == NULL)
343		pi->pi_samplename = pmcstat_string_intern(name);
344	else {
345		/*
346		 * Otherwise use a prefix from the original name and
347		 * up to 3 digits.
348		 */
349		nlen = strlen(sn);
350		nlen = min(nlen, (int) (sizeof(name)-sizeof("~NNN.gmon")));
351		count = 0;
352		do {
353			if (++count > 999)
354				errx(EX_CANTCREAT,
355				    "ERROR: cannot create a gmon file for"
356				    " \"%s\"", name);
357			snprintf(name, sizeof(name), "%.*s~%3.3d.gmon",
358			    nlen, sn, count);
359			if (pmcstat_string_lookup(name) == NULL) {
360				pi->pi_samplename =
361				    pmcstat_string_intern(name);
362				count = 0;
363			}
364		} while (count > 0);
365	}
366	free(snbuf);
367
368	LIST_INIT(&pi->pi_gmlist);
369}
370
371void
372pmcpl_gmon_shutdownimage(struct pmcstat_image *pi)
373{
374	struct pmcstat_gmonfile *pgf, *pgftmp;
375
376	LIST_FOREACH_SAFE(pgf, &pi->pi_gmlist, pgf_next, pgftmp) {
377		if (pgf->pgf_file)
378			(void) fclose(pgf->pgf_file);
379		LIST_REMOVE(pgf, pgf_next);
380		free(pgf);
381	}
382}
383
384void
385pmcpl_gmon_newpmc(pmcstat_interned_string ps, struct pmcstat_pmcrecord *pr)
386{
387	struct stat st;
388	char fullpath[PATH_MAX];
389
390	(void) pr;
391
392	/*
393	 * Create the appropriate directory to hold gmon.out files.
394	 */
395
396	(void) snprintf(fullpath, sizeof(fullpath), "%s/%s", args.pa_samplesdir,
397	    pmcstat_string_unintern(ps));
398
399	/* If the path name exists, it should be a directory */
400	if (stat(fullpath, &st) == 0 && S_ISDIR(st.st_mode))
401		return;
402
403	if (mkdir(fullpath, S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH) < 0)
404		err(EX_OSERR, "ERROR: Cannot create directory \"%s\"",
405		    fullpath);
406}
407
408/*
409 * Increment the bucket in the gmon.out file corresponding to 'pmcid'
410 * and 'pc'.
411 */
412
413void
414pmcpl_gmon_process(struct pmcstat_process *pp, struct pmcstat_pmcrecord *pmcr,
415    uint32_t nsamples, uintfptr_t *cc, int usermode, uint32_t cpu)
416{
417	struct pmcstat_pcmap *map;
418	struct pmcstat_image *image;
419	struct pmcstat_gmonfile *pgf;
420	uintfptr_t bucket;
421	HISTCOUNTER *hc;
422	WIDEHISTCOUNTER *whc;
423	pmc_id_t pmcid;
424
425	(void) nsamples; (void) usermode; (void) cpu;
426
427	map = pmcstat_process_find_map(usermode ? pp : pmcstat_kernproc, cc[0]);
428	if (map == NULL) {
429		/* Unknown offset. */
430		pmcstat_stats.ps_samples_unknown_offset++;
431		return;
432	}
433
434	assert(cc[0] >= map->ppm_lowpc && cc[0] < map->ppm_highpc);
435
436	image = map->ppm_image;
437	pmcid = pmcr->pr_pmcid;
438
439	/*
440	 * If this is the first time we are seeing a sample for
441	 * this executable image, try determine its parameters.
442	 */
443	if (image->pi_type == PMCSTAT_IMAGE_UNKNOWN)
444		pmcstat_image_determine_type(image, &args);
445
446	assert(image->pi_type != PMCSTAT_IMAGE_UNKNOWN);
447
448	/* Ignore samples in images that we know nothing about. */
449	if (image->pi_type == PMCSTAT_IMAGE_INDETERMINABLE) {
450		pmcstat_stats.ps_samples_indeterminable++;
451		return;
452	}
453
454	/*
455	 * Find the gmon file corresponding to 'pmcid', creating it if
456	 * needed.
457	 */
458	pgf = pmcstat_image_find_gmonfile(image, pmcid);
459	if (pgf == NULL) {
460		if (hc_sz == 0) {
461			/* Determine the correct histcounter size. */
462			if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC)
463				hc_sz = sizeof(WIDEHISTCOUNTER);
464			else
465				hc_sz = sizeof(HISTCOUNTER);
466		}
467
468		if ((pgf = calloc(1, sizeof(*pgf))) == NULL)
469			err(EX_OSERR, "ERROR:");
470
471		pgf->pgf_gmondata = NULL;	/* mark as unmapped */
472		pgf->pgf_name = pmcstat_gmon_create_name(args.pa_samplesdir,
473		    image, pmcid);
474		pgf->pgf_pmcid = pmcid;
475		assert(image->pi_end > image->pi_start);
476		pgf->pgf_nbuckets = howmany(image->pi_end - image->pi_start,
477		    FUNCTION_ALIGNMENT);	/* see <machine/profile.h> */
478		pgf->pgf_ndatabytes = sizeof(struct gmonhdr) +
479		    pgf->pgf_nbuckets * hc_sz;
480		pgf->pgf_nsamples = 0;
481		pgf->pgf_file = NULL;
482
483		pmcstat_gmon_create_file(pgf, image);
484
485		LIST_INSERT_HEAD(&image->pi_gmlist, pgf, pgf_next);
486	}
487
488	/*
489	 * Map the gmon file in if needed.  It may have been mapped
490	 * out under memory pressure.
491	 */
492	if (pgf->pgf_gmondata == NULL)
493		pmcstat_gmon_map_file(pgf);
494
495	assert(pgf->pgf_gmondata != NULL);
496
497	/*
498	 *
499	 */
500
501	bucket = (cc[0] - map->ppm_lowpc) / FUNCTION_ALIGNMENT;
502
503	assert(bucket < pgf->pgf_nbuckets);
504
505	if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC) {
506		whc = (WIDEHISTCOUNTER *) ((uintptr_t) pgf->pgf_gmondata +
507		    sizeof(struct gmonhdr));
508
509		/* saturating add */
510		if (whc[bucket] < WIDEHISTCOUNTER_MAX)
511			whc[bucket]++;
512		else /* mark that an overflow occurred */
513			pgf->pgf_overflow = 1;
514	} else {
515		hc = (HISTCOUNTER *) ((uintptr_t) pgf->pgf_gmondata +
516		    sizeof(struct gmonhdr));
517
518		/* saturating add */
519		if (hc[bucket] < HISTCOUNTER_MAX)
520			hc[bucket]++;
521		else /* mark that an overflow occurred */
522			pgf->pgf_overflow = 1;
523	}
524
525	pgf->pgf_nsamples++;
526}
527
528/*
529 * Shutdown module.
530 */
531
532void
533pmcpl_gmon_shutdown(FILE *mf)
534{
535	int i;
536	struct pmcstat_gmonfile *pgf;
537	struct pmcstat_image *pi;
538
539	/*
540	 * Sync back all gprof flat profile data.
541	 */
542	for (i = 0; i < PMCSTAT_NHASH; i++) {
543		LIST_FOREACH(pi, &pmcstat_image_hash[i], pi_next) {
544			if (mf)
545				(void) fprintf(mf, " \"%s\" => \"%s\"",
546				    pmcstat_string_unintern(pi->pi_execpath),
547				    pmcstat_string_unintern(
548				    pi->pi_samplename));
549
550			/* flush gmon.out data to disk */
551			LIST_FOREACH(pgf, &pi->pi_gmlist, pgf_next) {
552				pmcstat_gmon_unmap_file(pgf);
553				if (mf)
554					(void) fprintf(mf, " %s/%d",
555					    pmcstat_pmcid_to_name(
556					    pgf->pgf_pmcid),
557					    pgf->pgf_nsamples);
558				if (pgf->pgf_overflow && args.pa_verbosity >= 1)
559					warnx(
560"WARNING: profile \"%s\" overflowed.",
561					    pmcstat_string_unintern(
562					        pgf->pgf_name));
563			}
564
565			if (mf)
566				(void) fprintf(mf, "\n");
567		}
568	}
569
570	/*
571	 * Compute arcs and add these to the gprof files.
572	 */
573	if (args.pa_flags & FLAG_DO_GPROF && args.pa_graphdepth > 1)
574		pmcstat_callgraph_do_gmon_arcs();
575}
576