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         if (!pmcname)
 175                 err(EX_SOFTWARE, "ERROR: cannot find pmcid");
 176
 177         (void) snprintf(fullpath, sizeof(fullpath),
 178             "%s/%s/%s", samplesdir, pmcname,
 179             pmcstat_string_unintern(image->pi_samplename));
 180
 181         return (pmcstat_string_intern(fullpath));
 182 }
 183
 184
 185 /*
 186  * Mmap in a gmon.out file for processing.
 187  */
 188
 189 static void
 190 pmcstat_gmon_map_file(struct pmcstat_gmonfile *pgf)
 191 {
 192         int fd;
 193         const char *pathname;
 194
 195         pathname = pmcstat_string_unintern(pgf->pgf_name);
 196
 197         /* the gmon.out file must already exist */
 198         if ((fd = open(pathname, O_RDWR | O_NOFOLLOW, 0)) < 0)
 199                 err(EX_OSERR, "ERROR: cannot open \"%s\"", pathname);
 200
 201         pgf->pgf_gmondata = mmap(NULL, pgf->pgf_ndatabytes,
 202             PROT_READ|PROT_WRITE, MAP_NOSYNC|MAP_SHARED, fd, 0);
 203
 204         if (pgf->pgf_gmondata == MAP_FAILED)
 205                 err(EX_OSERR, "ERROR: cannot map \"%s\"", pathname);
 206
 207         (void) close(fd);
 208 }
 209
 210 /*
 211  * Unmap a gmon.out file after sync'ing its data to disk.
 212  */
 213
 214 static void
 215 pmcstat_gmon_unmap_file(struct pmcstat_gmonfile *pgf)
 216 {
 217         (void) msync(pgf->pgf_gmondata, pgf->pgf_ndatabytes,
 218             MS_SYNC);
 219         (void) munmap(pgf->pgf_gmondata, pgf->pgf_ndatabytes);
 220         pgf->pgf_gmondata = NULL;
 221 }
 222
 223 static void
 224 pmcstat_gmon_append_arc(struct pmcstat_image *image, pmc_id_t pmcid,
 225     uintptr_t rawfrom, uintptr_t rawto, uint32_t count)
 226 {
 227         struct rawarc arc;      /* from <sys/gmon.h> */
 228         const char *pathname;
 229         struct pmcstat_gmonfile *pgf;
 230
 231         if ((pgf = pmcstat_image_find_gmonfile(image, pmcid)) == NULL)
 232                 return;
 233
 234         if (pgf->pgf_file == NULL) {
 235                 pathname = pmcstat_string_unintern(pgf->pgf_name);
 236                 if ((pgf->pgf_file = fopen(pathname, "a")) == NULL)
 237                         return;
 238         }
 239
 240         arc.raw_frompc = rawfrom + image->pi_vaddr;
 241         arc.raw_selfpc = rawto + image->pi_vaddr;
 242         arc.raw_count = count;
 243
 244         (void) fwrite(&arc, sizeof(arc), 1, pgf->pgf_file);
 245
 246 }
 247
 248 static struct pmcstat_gmonfile *
 249 pmcstat_image_find_gmonfile(struct pmcstat_image *image, pmc_id_t pmcid)
 250 {
 251         struct pmcstat_gmonfile *pgf;
 252         LIST_FOREACH(pgf, &image->pi_gmlist, pgf_next)
 253             if (pgf->pgf_pmcid == pmcid)
 254                     return (pgf);
 255         return (NULL);
 256 }
 257
 258 static void
 259 pmcstat_cgnode_do_gmon_arcs(struct pmcstat_cgnode *cg, pmc_id_t pmcid)
 260 {
 261         struct pmcstat_cgnode *cgc;
 262
 263         /*
 264          * Look for child nodes that belong to the same image.
 265          */
 266
 267         LIST_FOREACH(cgc, &cg->pcg_children, pcg_sibling) {
 268                 if (cgc->pcg_image == cg->pcg_image)
 269                         pmcstat_gmon_append_arc(cg->pcg_image, pmcid,
 270                             cgc->pcg_func, cg->pcg_func, cgc->pcg_count);
 271                 if (cgc->pcg_nchildren > 0)
 272                         pmcstat_cgnode_do_gmon_arcs(cgc, pmcid);
 273         }
 274 }
 275
 276 static void
 277 pmcstat_callgraph_do_gmon_arcs_for_pmcid(pmc_id_t pmcid)
 278 {
 279         int n;
 280         struct pmcstat_cgnode_hash *pch;
 281
 282         for (n = 0; n < PMCSTAT_NHASH; n++)
 283                 LIST_FOREACH(pch, &pmcstat_cgnode_hash[n], pch_next)
 284                         if (pch->pch_pmcid == pmcid &&
 285                             pch->pch_cgnode->pcg_nchildren > 1)
 286                                 pmcstat_cgnode_do_gmon_arcs(pch->pch_cgnode,
 287                                     pmcid);
 288 }
 289
 290
 291 static void
 292 pmcstat_callgraph_do_gmon_arcs(void)
 293 {
 294         struct pmcstat_pmcrecord *pmcr;
 295
 296         LIST_FOREACH(pmcr, &pmcstat_pmcs, pr_next)
 297                 pmcstat_callgraph_do_gmon_arcs_for_pmcid(pmcr->pr_pmcid);
 298 }
 299
 300 void
 301 pmcpl_gmon_initimage(struct pmcstat_image *pi)
 302 {
 303         int count, nlen;
 304         char *sn;
 305         char name[NAME_MAX];
 306
 307         /*
 308          * Look for a suitable name for the sample files associated
 309          * with this image: if `basename(path)`+".gmon" is available,
 310          * we use that, otherwise we try iterating through
 311          * `basename(path)`+ "~" + NNN + ".gmon" till we get a free
 312          * entry.
 313          */
 314         if ((sn = basename(pmcstat_string_unintern(pi->pi_execpath))) == NULL)
 315                 err(EX_OSERR, "ERROR: Cannot process \"%s\"",
 316                     pmcstat_string_unintern(pi->pi_execpath));
 317
 318         nlen = strlen(sn);
 319         nlen = min(nlen, (int) (sizeof(name) - sizeof(".gmon")));
 320
 321         snprintf(name, sizeof(name), "%.*s.gmon", nlen, sn);
 322
 323         /* try use the unabridged name first */
 324         if (pmcstat_string_lookup(name) == NULL)
 325                 pi->pi_samplename = pmcstat_string_intern(name);
 326         else {
 327                 /*
 328                  * Otherwise use a prefix from the original name and
 329                  * up to 3 digits.
 330                  */
 331                 nlen = strlen(sn);
 332                 nlen = min(nlen, (int) (sizeof(name)-sizeof("~NNN.gmon")));
 333                 count = 0;
 334                 do {
 335                         if (++count > 999)
 336                                 errx(EX_CANTCREAT,
 337                                     "ERROR: cannot create a gmon file for"
 338                                     " \"%s\"", name);
 339                         snprintf(name, sizeof(name), "%.*s~%3.3d.gmon",
 340                             nlen, sn, count);
 341                         if (pmcstat_string_lookup(name) == NULL) {
 342                                 pi->pi_samplename =
 343                                     pmcstat_string_intern(name);
 344                                 count = 0;
 345                         }
 346                 } while (count > 0);
 347         }
 348
 349         LIST_INIT(&pi->pi_gmlist);
 350 }
 351
 352 void
 353 pmcpl_gmon_shutdownimage(struct pmcstat_image *pi)
 354 {
 355         struct pmcstat_gmonfile *pgf, *pgftmp;
 356
 357         LIST_FOREACH_SAFE(pgf, &pi->pi_gmlist, pgf_next, pgftmp) {
 358                 if (pgf->pgf_file)
 359                         (void) fclose(pgf->pgf_file);
 360                 LIST_REMOVE(pgf, pgf_next);
 361                 free(pgf);
 362         }
 363 }
 364
 365 void
 366 pmcpl_gmon_newpmc(pmcstat_interned_string ps, struct pmcstat_pmcrecord *pr)
 367 {
 368         struct stat st;
 369         char fullpath[PATH_MAX];
 370
 371         (void) pr;
 372
 373         /*
 374          * Create the appropriate directory to hold gmon.out files.
 375          */
 376
 377         (void) snprintf(fullpath, sizeof(fullpath), "%s/%s", args.pa_samplesdir,
 378             pmcstat_string_unintern(ps));
 379
 380         /* If the path name exists, it should be a directory */
 381         if (stat(fullpath, &st) == 0 && S_ISDIR(st.st_mode))
 382                 return;
 383
 384         if (mkdir(fullpath, S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH) < 0)
 385                 err(EX_OSERR, "ERROR: Cannot create directory \"%s\"",
 386                     fullpath);
 387 }
 388
 389 /*
 390  * Increment the bucket in the gmon.out file corresponding to 'pmcid'
 391  * and 'pc'.
 392  */
 393
 394 void
 395 pmcpl_gmon_process(struct pmcstat_process *pp, struct pmcstat_pmcrecord *pmcr,
 396     uint32_t nsamples, uintfptr_t *cc, int usermode, uint32_t cpu)
 397 {
 398         struct pmcstat_pcmap *map;
 399         struct pmcstat_image *image;
 400         struct pmcstat_gmonfile *pgf;
 401         uintfptr_t bucket;
 402         HISTCOUNTER *hc;
 403         pmc_id_t pmcid;
 404
 405         (void) nsamples; (void) usermode; (void) cpu;
 406
 407         map = pmcstat_process_find_map(usermode ? pp : pmcstat_kernproc, cc[0]);
 408         if (map == NULL) {
 409                 /* Unknown offset. */
 410                 pmcstat_stats.ps_samples_unknown_offset++;
 411                 return;
 412         }
 413
 414         assert(cc[0] >= map->ppm_lowpc && cc[0] < map->ppm_highpc);
 415
 416         image = map->ppm_image;
 417         pmcid = pmcr->pr_pmcid;
 418
 419         /*
 420          * If this is the first time we are seeing a sample for
 421          * this executable image, try determine its parameters.
 422          */
 423         if (image->pi_type == PMCSTAT_IMAGE_UNKNOWN)
 424                 pmcstat_image_determine_type(image);
 425
 426         assert(image->pi_type != PMCSTAT_IMAGE_UNKNOWN);
 427
 428         /* Ignore samples in images that we know nothing about. */
 429         if (image->pi_type == PMCSTAT_IMAGE_INDETERMINABLE) {
 430                 pmcstat_stats.ps_samples_indeterminable++;
 431                 return;
 432         }
 433
 434         /*
 435          * Find the gmon file corresponding to 'pmcid', creating it if
 436          * needed.
 437          */
 438         pgf = pmcstat_image_find_gmonfile(image, pmcid);
 439         if (pgf == NULL) {
 440                 if ((pgf = calloc(1, sizeof(*pgf))) == NULL)
 441                         err(EX_OSERR, "ERROR:");
 442
 443                 pgf->pgf_gmondata = NULL;       /* mark as unmapped */
 444                 pgf->pgf_name = pmcstat_gmon_create_name(args.pa_samplesdir,
 445                     image, pmcid);
 446                 pgf->pgf_pmcid = pmcid;
 447                 assert(image->pi_end > image->pi_start);
 448                 pgf->pgf_nbuckets = (image->pi_end - image->pi_start) /
 449                     FUNCTION_ALIGNMENT; /* see <machine/profile.h> */
 450                 pgf->pgf_ndatabytes = sizeof(struct gmonhdr) +
 451                     pgf->pgf_nbuckets * sizeof(HISTCOUNTER);
 452                 pgf->pgf_nsamples = 0;
 453                 pgf->pgf_file = NULL;
 454
 455                 pmcstat_gmon_create_file(pgf, image);
 456
 457                 LIST_INSERT_HEAD(&image->pi_gmlist, pgf, pgf_next);
 458         }
 459
 460         /*
 461          * Map the gmon file in if needed.  It may have been mapped
 462          * out under memory pressure.
 463          */
 464         if (pgf->pgf_gmondata == NULL)
 465                 pmcstat_gmon_map_file(pgf);
 466
 467         assert(pgf->pgf_gmondata != NULL);
 468
 469         /*
 470          *
 471          */
 472
 473         bucket = (cc[0] - map->ppm_lowpc) / FUNCTION_ALIGNMENT;
 474
 475         assert(bucket < pgf->pgf_nbuckets);
 476
 477         hc = (HISTCOUNTER *) ((uintptr_t) pgf->pgf_gmondata +
 478             sizeof(struct gmonhdr));
 479
 480         /* saturating add */
 481         if (hc[bucket] < 0xFFFFU)  /* XXX tie this to sizeof(HISTCOUNTER) */
 482                 hc[bucket]++;
 483         else /* mark that an overflow occurred */
 484                 pgf->pgf_overflow = 1;
 485
 486         pgf->pgf_nsamples++;
 487 }
 488
 489 /*
 490  * Shutdown module.
 491  */
 492
 493 void
 494 pmcpl_gmon_shutdown(FILE *mf)
 495 {
 496         int i;
 497         struct pmcstat_gmonfile *pgf;
 498         struct pmcstat_image *pi;
 499
 500         /*
 501          * Sync back all gprof flat profile data.
 502          */
 503         for (i = 0; i < PMCSTAT_NHASH; i++) {
 504                 LIST_FOREACH(pi, &pmcstat_image_hash[i], pi_next) {
 505                         if (mf)
 506                                 (void) fprintf(mf, " \"%s\" => \"%s\"",
 507                                     pmcstat_string_unintern(pi->pi_execpath),
 508                                     pmcstat_string_unintern(
 509                                     pi->pi_samplename));
 510
 511                         /* flush gmon.out data to disk */
 512                         LIST_FOREACH(pgf, &pi->pi_gmlist, pgf_next) {
 513                                 pmcstat_gmon_unmap_file(pgf);
 514                                 if (mf)
 515                                         (void) fprintf(mf, " %s/%d",
 516                                             pmcstat_pmcid_to_name(
 517                                             pgf->pgf_pmcid),
 518                                             pgf->pgf_nsamples);
 519                                 if (pgf->pgf_overflow && args.pa_verbosity >= 1)
 520                                         warnx(
 521 "WARNING: profile \"%s\" overflowed.",
 522                                             pmcstat_string_unintern(
 523                                                 pgf->pgf_name));
 524                         }
 525
 526                         if (mf)
 527                                 (void) fprintf(mf, "\n");
 528                 }
 529         }
 530
 531         /*
 532          * Compute arcs and add these to the gprof files.
 533          */
 534         if (args.pa_flags & FLAG_DO_GPROF && args.pa_graphdepth > 1)
 535                 pmcstat_callgraph_do_gmon_arcs();
 536 }