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 typedef uint64_t        WIDEHISTCOUNTER;
  78
  79 #define min(A,B)                ((A) < (B) ? (A) : (B))
  80 #define max(A,B)                ((A) > (B) ? (A) : (B))
  81
  82 #define WIDEHISTCOUNTER_MAX             UINT64_MAX
  83 #define HISTCOUNTER_MAX                 USHRT_MAX
  84 #define WIDEHISTCOUNTER_GMONTYPE        ((int) 64)
  85 #define HISTCOUNTER_GMONTYPE            ((int) 0)
  86 static int hc_sz=0;
  87
  88 /*
  89  * struct pmcstat_gmonfile tracks a given 'gmon.out' file.  These
  90  * files are mmap()'ed in as needed.
  91  */
  92
  93 struct pmcstat_gmonfile {
  94         LIST_ENTRY(pmcstat_gmonfile)    pgf_next; /* list of entries */
  95         int             pgf_overflow;   /* whether a count overflowed */
  96         pmc_id_t        pgf_pmcid;      /* id of the associated pmc */
  97         size_t          pgf_nbuckets;   /* #buckets in this gmon.out */
  98         unsigned int    pgf_nsamples;   /* #samples in this gmon.out */
  99         pmcstat_interned_string pgf_name;       /* pathname of gmon.out file */
 100         size_t          pgf_ndatabytes; /* number of bytes mapped */
 101         void            *pgf_gmondata;  /* pointer to mmap'ed data */
 102         FILE            *pgf_file;      /* used when writing gmon arcs */
 103 };
 104
 105 /*
 106  * Prototypes
 107  */
 108
 109 static void     pmcstat_gmon_create_file(struct pmcstat_gmonfile *_pgf,
 110     struct pmcstat_image *_image);
 111 static pmcstat_interned_string pmcstat_gmon_create_name(const char *_sd,
 112     struct pmcstat_image *_img, pmc_id_t _pmcid);
 113 static void     pmcstat_gmon_map_file(struct pmcstat_gmonfile *_pgf);
 114 static void     pmcstat_gmon_unmap_file(struct pmcstat_gmonfile *_pgf);
 115
 116 static struct pmcstat_gmonfile *pmcstat_image_find_gmonfile(struct
 117     pmcstat_image *_i, pmc_id_t _id);
 118
 119 /*
 120  * Create a gmon.out file and size it.
 121  */
 122
 123 static void
 124 pmcstat_gmon_create_file(struct pmcstat_gmonfile *pgf,
 125     struct pmcstat_image *image)
 126 {
 127         int fd;
 128         size_t count;
 129         struct gmonhdr gm;
 130         const char *pathname;
 131         char buffer[DEFAULT_BUFFER_SIZE];
 132
 133         pathname = pmcstat_string_unintern(pgf->pgf_name);
 134         if ((fd = open(pathname, O_RDWR|O_NOFOLLOW|O_CREAT,
 135                  S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)) < 0)
 136                 err(EX_OSERR, "ERROR: Cannot open \"%s\"", pathname);
 137
 138         gm.lpc = image->pi_start;
 139         gm.hpc = image->pi_end;
 140         gm.ncnt = (pgf->pgf_nbuckets * hc_sz) + sizeof(struct gmonhdr);
 141         gm.version = GMONVERSION;
 142         gm.profrate = 0;                /* use ticks */
 143         if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC)
 144                 gm.histcounter_type = WIDEHISTCOUNTER_GMONTYPE;
 145         else
 146                 gm.histcounter_type = HISTCOUNTER_GMONTYPE;
 147         gm.spare[0] = gm.spare[1] = 0;
 148
 149         /* Write out the gmon header */
 150         if (write(fd, &gm, sizeof(gm)) < 0)
 151                 goto error;
 152
 153         /* Zero fill the samples[] array */
 154         (void) memset(buffer, 0, sizeof(buffer));
 155
 156         count = pgf->pgf_ndatabytes - sizeof(struct gmonhdr);
 157         while (count > sizeof(buffer)) {
 158                 if (write(fd, &buffer, sizeof(buffer)) < 0)
 159                         goto error;
 160                 count -= sizeof(buffer);
 161         }
 162
 163         if (write(fd, &buffer, count) < 0)
 164                 goto error;
 165
 166         (void) close(fd);
 167
 168         return;
 169
 170  error:
 171         err(EX_OSERR, "ERROR: Cannot write \"%s\"", pathname);
 172 }
 173
 174 /*
 175  * Determine the full pathname of a gmon.out file for a given
 176  * (image,pmcid) combination.  Return the interned string.
 177  */
 178
 179 pmcstat_interned_string
 180 pmcstat_gmon_create_name(const char *samplesdir, struct pmcstat_image *image,
 181     pmc_id_t pmcid)
 182 {
 183         const char *pmcname;
 184         char fullpath[PATH_MAX];
 185
 186         pmcname = pmcstat_pmcid_to_name(pmcid);
 187         if (!pmcname)
 188                 err(EX_SOFTWARE, "ERROR: cannot find pmcid");
 189
 190         (void) snprintf(fullpath, sizeof(fullpath),
 191             "%s/%s/%s", samplesdir, pmcname,
 192             pmcstat_string_unintern(image->pi_samplename));
 193
 194         return (pmcstat_string_intern(fullpath));
 195 }
 196
 197
 198 /*
 199  * Mmap in a gmon.out file for processing.
 200  */
 201
 202 static void
 203 pmcstat_gmon_map_file(struct pmcstat_gmonfile *pgf)
 204 {
 205         int fd;
 206         const char *pathname;
 207
 208         pathname = pmcstat_string_unintern(pgf->pgf_name);
 209
 210         /* the gmon.out file must already exist */
 211         if ((fd = open(pathname, O_RDWR | O_NOFOLLOW, 0)) < 0)
 212                 err(EX_OSERR, "ERROR: cannot open \"%s\"", pathname);
 213
 214         pgf->pgf_gmondata = mmap(NULL, pgf->pgf_ndatabytes,
 215             PROT_READ|PROT_WRITE, MAP_NOSYNC|MAP_SHARED, fd, 0);
 216
 217         if (pgf->pgf_gmondata == MAP_FAILED)
 218                 err(EX_OSERR, "ERROR: cannot map \"%s\"", pathname);
 219
 220         (void) close(fd);
 221 }
 222
 223 /*
 224  * Unmap a gmon.out file after sync'ing its data to disk.
 225  */
 226
 227 static void
 228 pmcstat_gmon_unmap_file(struct pmcstat_gmonfile *pgf)
 229 {
 230         (void) msync(pgf->pgf_gmondata, pgf->pgf_ndatabytes,
 231             MS_SYNC);
 232         (void) munmap(pgf->pgf_gmondata, pgf->pgf_ndatabytes);
 233         pgf->pgf_gmondata = NULL;
 234 }
 235
 236 static void
 237 pmcstat_gmon_append_arc(struct pmcstat_image *image, pmc_id_t pmcid,
 238     uintptr_t rawfrom, uintptr_t rawto, uint32_t count)
 239 {
 240         struct rawarc arc;      /* from <sys/gmon.h> */
 241         const char *pathname;
 242         struct pmcstat_gmonfile *pgf;
 243
 244         if ((pgf = pmcstat_image_find_gmonfile(image, pmcid)) == NULL)
 245                 return;
 246
 247         if (pgf->pgf_file == NULL) {
 248                 pathname = pmcstat_string_unintern(pgf->pgf_name);
 249                 if ((pgf->pgf_file = fopen(pathname, "a")) == NULL)
 250                         return;
 251         }
 252
 253         arc.raw_frompc = rawfrom + image->pi_vaddr;
 254         arc.raw_selfpc = rawto + image->pi_vaddr;
 255         arc.raw_count = count;
 256
 257         (void) fwrite(&arc, sizeof(arc), 1, pgf->pgf_file);
 258
 259 }
 260
 261 static struct pmcstat_gmonfile *
 262 pmcstat_image_find_gmonfile(struct pmcstat_image *image, pmc_id_t pmcid)
 263 {
 264         struct pmcstat_gmonfile *pgf;
 265         LIST_FOREACH(pgf, &image->pi_gmlist, pgf_next)
 266             if (pgf->pgf_pmcid == pmcid)
 267                     return (pgf);
 268         return (NULL);
 269 }
 270
 271 static void
 272 pmcstat_cgnode_do_gmon_arcs(struct pmcstat_cgnode *cg, pmc_id_t pmcid)
 273 {
 274         struct pmcstat_cgnode *cgc;
 275
 276         /*
 277          * Look for child nodes that belong to the same image.
 278          */
 279
 280         LIST_FOREACH(cgc, &cg->pcg_children, pcg_sibling) {
 281                 if (cgc->pcg_image == cg->pcg_image)
 282                         pmcstat_gmon_append_arc(cg->pcg_image, pmcid,
 283                             cgc->pcg_func, cg->pcg_func, cgc->pcg_count);
 284                 if (cgc->pcg_nchildren > 0)
 285                         pmcstat_cgnode_do_gmon_arcs(cgc, pmcid);
 286         }
 287 }
 288
 289 static void
 290 pmcstat_callgraph_do_gmon_arcs_for_pmcid(pmc_id_t pmcid)
 291 {
 292         int n;
 293         struct pmcstat_cgnode_hash *pch;
 294
 295         for (n = 0; n < PMCSTAT_NHASH; n++)
 296                 LIST_FOREACH(pch, &pmcstat_cgnode_hash[n], pch_next)
 297                         if (pch->pch_pmcid == pmcid &&
 298                             pch->pch_cgnode->pcg_nchildren > 1)
 299                                 pmcstat_cgnode_do_gmon_arcs(pch->pch_cgnode,
 300                                     pmcid);
 301 }
 302
 303
 304 static void
 305 pmcstat_callgraph_do_gmon_arcs(void)
 306 {
 307         struct pmcstat_pmcrecord *pmcr;
 308
 309         LIST_FOREACH(pmcr, &pmcstat_pmcs, pr_next)
 310                 pmcstat_callgraph_do_gmon_arcs_for_pmcid(pmcr->pr_pmcid);
 311 }
 312
 313 void
 314 pmcpl_gmon_initimage(struct pmcstat_image *pi)
 315 {
 316         const char *execpath;
 317         int count, nlen;
 318         char *sn, *snbuf;
 319         char name[NAME_MAX];
 320
 321         /*
 322          * Look for a suitable name for the sample files associated
 323          * with this image: if `basename(path)`+".gmon" is available,
 324          * we use that, otherwise we try iterating through
 325          * `basename(path)`+ "~" + NNN + ".gmon" till we get a free
 326          * entry.
 327          */
 328         execpath = pmcstat_string_unintern(pi->pi_execpath);
 329         if ((snbuf = strdup(execpath)) == NULL)
 330                 err(EX_OSERR, "ERROR: Cannot copy \"%s\"", execpath);
 331         if ((sn = basename(snbuf)) == NULL)
 332                 err(EX_OSERR, "ERROR: Cannot process \"%s\"", execpath);
 333
 334         nlen = strlen(sn);
 335         nlen = min(nlen, (int) (sizeof(name) - sizeof(".gmon")));
 336
 337         snprintf(name, sizeof(name), "%.*s.gmon", nlen, sn);
 338
 339         /* try use the unabridged name first */
 340         if (pmcstat_string_lookup(name) == NULL)
 341                 pi->pi_samplename = pmcstat_string_intern(name);
 342         else {
 343                 /*
 344                  * Otherwise use a prefix from the original name and
 345                  * up to 3 digits.
 346                  */
 347                 nlen = strlen(sn);
 348                 nlen = min(nlen, (int) (sizeof(name)-sizeof("~NNN.gmon")));
 349                 count = 0;
 350                 do {
 351                         if (++count > 999)
 352                                 errx(EX_CANTCREAT,
 353                                     "ERROR: cannot create a gmon file for"
 354                                     " \"%s\"", name);
 355                         snprintf(name, sizeof(name), "%.*s~%3.3d.gmon",
 356                             nlen, sn, count);
 357                         if (pmcstat_string_lookup(name) == NULL) {
 358                                 pi->pi_samplename =
 359                                     pmcstat_string_intern(name);
 360                                 count = 0;
 361                         }
 362                 } while (count > 0);
 363         }
 364         free(snbuf);
 365
 366         LIST_INIT(&pi->pi_gmlist);
 367 }
 368
 369 void
 370 pmcpl_gmon_shutdownimage(struct pmcstat_image *pi)
 371 {
 372         struct pmcstat_gmonfile *pgf, *pgftmp;
 373
 374         LIST_FOREACH_SAFE(pgf, &pi->pi_gmlist, pgf_next, pgftmp) {
 375                 if (pgf->pgf_file)
 376                         (void) fclose(pgf->pgf_file);
 377                 LIST_REMOVE(pgf, pgf_next);
 378                 free(pgf);
 379         }
 380 }
 381
 382 void
 383 pmcpl_gmon_newpmc(pmcstat_interned_string ps, struct pmcstat_pmcrecord *pr)
 384 {
 385         struct stat st;
 386         char fullpath[PATH_MAX];
 387
 388         (void) pr;
 389
 390         /*
 391          * Create the appropriate directory to hold gmon.out files.
 392          */
 393
 394         (void) snprintf(fullpath, sizeof(fullpath), "%s/%s", args.pa_samplesdir,
 395             pmcstat_string_unintern(ps));
 396
 397         /* If the path name exists, it should be a directory */
 398         if (stat(fullpath, &st) == 0 && S_ISDIR(st.st_mode))
 399                 return;
 400
 401         if (mkdir(fullpath, S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH) < 0)
 402                 err(EX_OSERR, "ERROR: Cannot create directory \"%s\"",
 403                     fullpath);
 404 }
 405
 406 /*
 407  * Increment the bucket in the gmon.out file corresponding to 'pmcid'
 408  * and 'pc'.
 409  */
 410
 411 void
 412 pmcpl_gmon_process(struct pmcstat_process *pp, struct pmcstat_pmcrecord *pmcr,
 413     uint32_t nsamples, uintfptr_t *cc, int usermode, uint32_t cpu)
 414 {
 415         struct pmcstat_pcmap *map;
 416         struct pmcstat_image *image;
 417         struct pmcstat_gmonfile *pgf;
 418         uintfptr_t bucket;
 419         HISTCOUNTER *hc;
 420         WIDEHISTCOUNTER *whc;
 421         pmc_id_t pmcid;
 422
 423         (void) nsamples; (void) usermode; (void) cpu;
 424
 425         map = pmcstat_process_find_map(usermode ? pp : pmcstat_kernproc, cc[0]);
 426         if (map == NULL) {
 427                 /* Unknown offset. */
 428                 pmcstat_stats.ps_samples_unknown_offset++;
 429                 return;
 430         }
 431
 432         assert(cc[0] >= map->ppm_lowpc && cc[0] < map->ppm_highpc);
 433
 434         image = map->ppm_image;
 435         pmcid = pmcr->pr_pmcid;
 436
 437         /*
 438          * If this is the first time we are seeing a sample for
 439          * this executable image, try determine its parameters.
 440          */
 441         if (image->pi_type == PMCSTAT_IMAGE_UNKNOWN)
 442                 pmcstat_image_determine_type(image, &args);
 443
 444         assert(image->pi_type != PMCSTAT_IMAGE_UNKNOWN);
 445
 446         /* Ignore samples in images that we know nothing about. */
 447         if (image->pi_type == PMCSTAT_IMAGE_INDETERMINABLE) {
 448                 pmcstat_stats.ps_samples_indeterminable++;
 449                 return;
 450         }
 451
 452         /*
 453          * Find the gmon file corresponding to 'pmcid', creating it if
 454          * needed.
 455          */
 456         pgf = pmcstat_image_find_gmonfile(image, pmcid);
 457         if (pgf == NULL) {
 458                 if (hc_sz == 0) {
 459                         /* Determine the correct histcounter size. */
 460                         if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC)
 461                                 hc_sz = sizeof(WIDEHISTCOUNTER);
 462                         else
 463                                 hc_sz = sizeof(HISTCOUNTER);
 464                 }
 465
 466                 if ((pgf = calloc(1, sizeof(*pgf))) == NULL)
 467                         err(EX_OSERR, "ERROR:");
 468
 469                 pgf->pgf_gmondata = NULL;       /* mark as unmapped */
 470                 pgf->pgf_name = pmcstat_gmon_create_name(args.pa_samplesdir,
 471                     image, pmcid);
 472                 pgf->pgf_pmcid = pmcid;
 473                 assert(image->pi_end > image->pi_start);
 474                 pgf->pgf_nbuckets = howmany(image->pi_end - image->pi_start,
 475                     FUNCTION_ALIGNMENT);        /* see <machine/profile.h> */
 476                 pgf->pgf_ndatabytes = sizeof(struct gmonhdr) +
 477                     pgf->pgf_nbuckets * hc_sz;
 478                 pgf->pgf_nsamples = 0;
 479                 pgf->pgf_file = NULL;
 480
 481                 pmcstat_gmon_create_file(pgf, image);
 482
 483                 LIST_INSERT_HEAD(&image->pi_gmlist, pgf, pgf_next);
 484         }
 485
 486         /*
 487          * Map the gmon file in if needed.  It may have been mapped
 488          * out under memory pressure.
 489          */
 490         if (pgf->pgf_gmondata == NULL)
 491                 pmcstat_gmon_map_file(pgf);
 492
 493         assert(pgf->pgf_gmondata != NULL);
 494
 495         /*
 496          *
 497          */
 498
 499         bucket = (cc[0] - map->ppm_lowpc) / FUNCTION_ALIGNMENT;
 500
 501         assert(bucket < pgf->pgf_nbuckets);
 502
 503         if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC) {
 504                 whc = (WIDEHISTCOUNTER *) ((uintptr_t) pgf->pgf_gmondata +
 505                     sizeof(struct gmonhdr));
 506
 507                 /* saturating add */
 508                 if (whc[bucket] < WIDEHISTCOUNTER_MAX)
 509                         whc[bucket]++;
 510                 else /* mark that an overflow occurred */
 511                         pgf->pgf_overflow = 1;
 512         } else {
 513                 hc = (HISTCOUNTER *) ((uintptr_t) pgf->pgf_gmondata +
 514                     sizeof(struct gmonhdr));
 515
 516                 /* saturating add */
 517                 if (hc[bucket] < HISTCOUNTER_MAX)
 518                         hc[bucket]++;
 519                 else /* mark that an overflow occurred */
 520                         pgf->pgf_overflow = 1;
 521         }
 522
 523         pgf->pgf_nsamples++;
 524 }
 525
 526 /*
 527  * Shutdown module.
 528  */
 529
 530 void
 531 pmcpl_gmon_shutdown(FILE *mf)
 532 {
 533         int i;
 534         struct pmcstat_gmonfile *pgf;
 535         struct pmcstat_image *pi;
 536
 537         /*
 538          * Sync back all gprof flat profile data.
 539          */
 540         for (i = 0; i < PMCSTAT_NHASH; i++) {
 541                 LIST_FOREACH(pi, &pmcstat_image_hash[i], pi_next) {
 542                         if (mf)
 543                                 (void) fprintf(mf, " \"%s\" => \"%s\"",
 544                                     pmcstat_string_unintern(pi->pi_execpath),
 545                                     pmcstat_string_unintern(
 546                                     pi->pi_samplename));
 547
 548                         /* flush gmon.out data to disk */
 549                         LIST_FOREACH(pgf, &pi->pi_gmlist, pgf_next) {
 550                                 pmcstat_gmon_unmap_file(pgf);
 551                                 if (mf)
 552                                         (void) fprintf(mf, " %s/%d",
 553                                             pmcstat_pmcid_to_name(
 554                                             pgf->pgf_pmcid),
 555                                             pgf->pgf_nsamples);
 556                                 if (pgf->pgf_overflow && args.pa_verbosity >= 1)
 557                                         warnx(
 558 "WARNING: profile \"%s\" overflowed.",
 559                                             pmcstat_string_unintern(
 560                                                 pgf->pgf_name));
 561                         }
 562
 563                         if (mf)
 564                                 (void) fprintf(mf, "\n");
 565                 }
 566         }
 567
 568         /*
 569          * Compute arcs and add these to the gprof files.
 570          */
 571         if (args.pa_flags & FLAG_DO_GPROF && args.pa_graphdepth > 1)
 572                 pmcstat_callgraph_do_gmon_arcs();
 573 }