usr.sbin/pmcstat/pmcpl_gprof.c

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