DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (27a812186ff4)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=8 sts=4 et sw=4 tw=99:
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/* Profiling-related API */

#include "builtin/Profilers.h"

#include <stdarg.h>

#ifdef MOZ_CALLGRIND
# include <valgrind/callgrind.h>
#endif

#ifdef __APPLE__
#ifdef MOZ_INSTRUMENTS
# include "devtools/Instruments.h"
#endif
#ifdef MOZ_SHARK
# include "devtools/sharkctl.h"
#endif
#endif

#ifdef XP_WIN
# include <process.h>
# define getpid _getpid
#endif

#include "vm/Probes.h"

#include "jscntxtinlines.h"

using namespace js;

using mozilla::ArrayLength;

/* Thread-unsafe error management */

static char gLastError[2000];

static void
#ifdef __GNUC__
__attribute__((unused,format(printf,1,2)))
#endif
UnsafeError(const char* format, ...)
{
    va_list args;
    va_start(args, format);
    (void) vsnprintf(gLastError, sizeof(gLastError), format, args);
    va_end(args);

    gLastError[sizeof(gLastError) - 1] = '\0';
}

JS_PUBLIC_API(const char*)
JS_UnsafeGetLastProfilingError()
{
    return gLastError;
}

#ifdef __APPLE__
static bool
StartOSXProfiling(const char* profileName, pid_t pid)
{
    bool ok = true;
    const char* profiler = nullptr;
#ifdef MOZ_SHARK
    ok = Shark::Start();
    profiler = "Shark";
#endif
#ifdef MOZ_INSTRUMENTS
    ok = Instruments::Start(pid);
    profiler = "Instruments";
#endif
    if (!ok) {
        if (profileName)
            UnsafeError("Failed to start %s for %s", profiler, profileName);
        else
            UnsafeError("Failed to start %s", profiler);
        return false;
    }
    return true;
}
#endif

JS_PUBLIC_API(bool)
JS_StartProfiling(const char* profileName, pid_t pid)
{
    bool ok = true;
#ifdef __APPLE__
    ok = StartOSXProfiling(profileName, pid);
#endif
#ifdef __linux__
    if (!js_StartPerf())
        ok = false;
#endif
    return ok;
}

JS_PUBLIC_API(bool)
JS_StopProfiling(const char* profileName)
{
    bool ok = true;
#ifdef __APPLE__
#ifdef MOZ_SHARK
    Shark::Stop();
#endif
#ifdef MOZ_INSTRUMENTS
    Instruments::Stop(profileName);
#endif
#endif
#ifdef __linux__
    if (!js_StopPerf())
        ok = false;
#endif
    return ok;
}

/*
 * Start or stop whatever platform- and configuration-specific profiling
 * backends are available.
 */
static bool
ControlProfilers(bool toState)
{
    bool ok = true;

    if (! probes::ProfilingActive && toState) {
#ifdef __APPLE__
#if defined(MOZ_SHARK) || defined(MOZ_INSTRUMENTS)
        const char* profiler;
#ifdef MOZ_SHARK
        ok = Shark::Start();
        profiler = "Shark";
#endif
#ifdef MOZ_INSTRUMENTS
        ok = Instruments::Resume();
        profiler = "Instruments";
#endif
        if (!ok) {
            UnsafeError("Failed to start %s", profiler);
        }
#endif
#endif
#ifdef MOZ_CALLGRIND
        if (! js_StartCallgrind()) {
            UnsafeError("Failed to start Callgrind");
            ok = false;
        }
#endif
    } else if (probes::ProfilingActive && ! toState) {
#ifdef __APPLE__
#ifdef MOZ_SHARK
        Shark::Stop();
#endif
#ifdef MOZ_INSTRUMENTS
        Instruments::Pause();
#endif
#endif
#ifdef MOZ_CALLGRIND
        if (! js_StopCallgrind()) {
            UnsafeError("failed to stop Callgrind");
            ok = false;
        }
#endif
    }

    probes::ProfilingActive = toState;

    return ok;
}

/*
 * Pause/resume whatever profiling mechanism is currently compiled
 * in, if applicable. This will not affect things like dtrace.
 *
 * Do not mix calls to these APIs with calls to the individual
 * profilers' pause/resume functions, because only overall state is
 * tracked, not the state of each profiler.
 */
JS_PUBLIC_API(bool)
JS_PauseProfilers(const char* profileName)
{
    return ControlProfilers(false);
}

JS_PUBLIC_API(bool)
JS_ResumeProfilers(const char* profileName)
{
    return ControlProfilers(true);
}

JS_PUBLIC_API(bool)
JS_DumpProfile(const char* outfile, const char* profileName)
{
    bool ok = true;
#ifdef MOZ_CALLGRIND
    js_DumpCallgrind(outfile);
#endif
    return ok;
}

#ifdef MOZ_PROFILING

struct RequiredStringArg {
    JSContext* mCx;
    char* mBytes;
    RequiredStringArg(JSContext* cx, const CallArgs& args, size_t argi, const char* caller)
        : mCx(cx), mBytes(nullptr)
    {
        if (args.length() <= argi) {
            JS_ReportError(cx, "%s: not enough arguments", caller);
        } else if (!args[argi].isString()) {
            JS_ReportError(cx, "%s: invalid arguments (string expected)", caller);
        } else {
            mBytes = JS_EncodeString(cx, args[argi].toString());
        }
    }
    operator void*() {
        return (void*) mBytes;
    }
    ~RequiredStringArg() {
        js_free(mBytes);
    }
};

static bool
StartProfiling(JSContext* cx, unsigned argc, jsval* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    if (args.length() == 0) {
        args.rval().setBoolean(JS_StartProfiling(nullptr, getpid()));
        return true;
    }

    RequiredStringArg profileName(cx, args, 0, "startProfiling");
    if (!profileName)
        return false;

    if (args.length() == 1) {
        args.rval().setBoolean(JS_StartProfiling(profileName.mBytes, getpid()));
        return true;
    }

    if (!args[1].isInt32()) {
        JS_ReportError(cx, "startProfiling: invalid arguments (int expected)");
        return false;
    }
    pid_t pid = static_cast<pid_t>(args[1].toInt32());
    args.rval().setBoolean(JS_StartProfiling(profileName.mBytes, pid));
    return true;
}

static bool
StopProfiling(JSContext* cx, unsigned argc, jsval* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    if (args.length() == 0) {
        args.rval().setBoolean(JS_StopProfiling(nullptr));
        return true;
    }

    RequiredStringArg profileName(cx, args, 0, "stopProfiling");
    if (!profileName)
        return false;
    args.rval().setBoolean(JS_StopProfiling(profileName.mBytes));
    return true;
}

static bool
PauseProfilers(JSContext* cx, unsigned argc, jsval* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    if (args.length() == 0) {
        args.rval().setBoolean(JS_PauseProfilers(nullptr));
        return true;
    }

    RequiredStringArg profileName(cx, args, 0, "pauseProfiling");
    if (!profileName)
        return false;
    args.rval().setBoolean(JS_PauseProfilers(profileName.mBytes));
    return true;
}

static bool
ResumeProfilers(JSContext* cx, unsigned argc, jsval* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    if (args.length() == 0) {
        args.rval().setBoolean(JS_ResumeProfilers(nullptr));
        return true;
    }

    RequiredStringArg profileName(cx, args, 0, "resumeProfiling");
    if (!profileName)
        return false;
    args.rval().setBoolean(JS_ResumeProfilers(profileName.mBytes));
    return true;
}

/* Usage: DumpProfile([filename[, profileName]]) */
static bool
DumpProfile(JSContext* cx, unsigned argc, jsval* vp)
{
    bool ret;
    CallArgs args = CallArgsFromVp(argc, vp);
    if (args.length() == 0) {
        ret = JS_DumpProfile(nullptr, nullptr);
    } else {
        RequiredStringArg filename(cx, args, 0, "dumpProfile");
        if (!filename)
            return false;

        if (args.length() == 1) {
            ret = JS_DumpProfile(filename.mBytes, nullptr);
        } else {
            RequiredStringArg profileName(cx, args, 1, "dumpProfile");
            if (!profileName)
                return false;

            ret = JS_DumpProfile(filename.mBytes, profileName.mBytes);
        }
    }

    args.rval().setBoolean(ret);
    return true;
}

#if defined(MOZ_SHARK) || defined(MOZ_INSTRUMENTS)

static bool
IgnoreAndReturnTrue(JSContext* cx, unsigned argc, jsval* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    args.rval().setBoolean(true);
    return true;
}

#endif

#ifdef MOZ_CALLGRIND
static bool
StartCallgrind(JSContext* cx, unsigned argc, jsval* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    args.rval().setBoolean(js_StartCallgrind());
    return true;
}

static bool
StopCallgrind(JSContext* cx, unsigned argc, jsval* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    args.rval().setBoolean(js_StopCallgrind());
    return true;
}

static bool
DumpCallgrind(JSContext* cx, unsigned argc, jsval* vp)
{
    CallArgs args = CallArgsFromVp(argc, vp);
    if (args.length() == 0) {
        args.rval().setBoolean(js_DumpCallgrind(nullptr));
        return true;
    }

    RequiredStringArg outFile(cx, args, 0, "dumpCallgrind");
    if (!outFile)
        return false;

    args.rval().setBoolean(js_DumpCallgrind(outFile.mBytes));
    return true;
}
#endif

static const JSFunctionSpec profiling_functions[] = {
    JS_FN("startProfiling",  StartProfiling,      1,0),
    JS_FN("stopProfiling",   StopProfiling,       1,0),
    JS_FN("pauseProfilers",  PauseProfilers,      1,0),
    JS_FN("resumeProfilers", ResumeProfilers,     1,0),
    JS_FN("dumpProfile",     DumpProfile,         2,0),
#if defined(MOZ_SHARK) || defined(MOZ_INSTRUMENTS)
    /* Keep users of the old shark API happy. */
    JS_FN("connectShark",    IgnoreAndReturnTrue, 0,0),
    JS_FN("disconnectShark", IgnoreAndReturnTrue, 0,0),
    JS_FN("startShark",      StartProfiling,      0,0),
    JS_FN("stopShark",       StopProfiling,       0,0),
#endif
#ifdef MOZ_CALLGRIND
    JS_FN("startCallgrind", StartCallgrind,       0,0),
    JS_FN("stopCallgrind",  StopCallgrind,        0,0),
    JS_FN("dumpCallgrind",  DumpCallgrind,        1,0),
#endif
    JS_FS_END
};

#endif

JS_PUBLIC_API(bool)
JS_DefineProfilingFunctions(JSContext* cx, JSObject* objArg)
{
    RootedObject obj(cx, objArg);

    assertSameCompartment(cx, obj);
#ifdef MOZ_PROFILING
    return JS_DefineFunctions(cx, obj, profiling_functions);
#else
    return true;
#endif
}

#ifdef MOZ_CALLGRIND

JS_FRIEND_API(bool)
js_StartCallgrind()
{
    JS_SILENCE_UNUSED_VALUE_IN_EXPR(CALLGRIND_START_INSTRUMENTATION);
    JS_SILENCE_UNUSED_VALUE_IN_EXPR(CALLGRIND_ZERO_STATS);
    return true;
}

JS_FRIEND_API(bool)
js_StopCallgrind()
{
    JS_SILENCE_UNUSED_VALUE_IN_EXPR(CALLGRIND_STOP_INSTRUMENTATION);
    return true;
}

JS_FRIEND_API(bool)
js_DumpCallgrind(const char* outfile)
{
    if (outfile) {
        JS_SILENCE_UNUSED_VALUE_IN_EXPR(CALLGRIND_DUMP_STATS_AT(outfile));
    } else {
        JS_SILENCE_UNUSED_VALUE_IN_EXPR(CALLGRIND_DUMP_STATS);
    }

    return true;
}

#endif /* MOZ_CALLGRIND */

#ifdef __linux__

/*
 * Code for starting and stopping |perf|, the Linux profiler.
 *
 * Output from profiling is written to mozperf.data in your cwd.
 *
 * To enable, set MOZ_PROFILE_WITH_PERF=1 in your environment.
 *
 * To pass additional parameters to |perf record|, provide them in the
 * MOZ_PROFILE_PERF_FLAGS environment variable.  If this variable does not
 * exist, we default it to "--call-graph".  (If you don't want --call-graph but
 * don't want to pass any other args, define MOZ_PROFILE_PERF_FLAGS to the empty
 * string.)
 *
 * If you include --pid or --output in MOZ_PROFILE_PERF_FLAGS, you're just
 * asking for trouble.
 *
 * Our split-on-spaces logic is lame, so don't expect MOZ_PROFILE_PERF_FLAGS to
 * work if you pass an argument which includes a space (e.g.
 * MOZ_PROFILE_PERF_FLAGS="-e 'foo bar'").
 */

#include <signal.h>
#include <sys/wait.h>
#include <unistd.h>

static bool perfInitialized = false;
static pid_t perfPid = 0;

bool js_StartPerf()
{
    const char* outfile = "mozperf.data";

    if (perfPid != 0) {
        UnsafeError("js_StartPerf: called while perf was already running!\n");
        return false;
    }

    // Bail if MOZ_PROFILE_WITH_PERF is empty or undefined.
    if (!getenv("MOZ_PROFILE_WITH_PERF") ||
        !strlen(getenv("MOZ_PROFILE_WITH_PERF"))) {
        return true;
    }

    /*
     * Delete mozperf.data the first time through -- we're going to append to it
     * later on, so we want it to be clean when we start out.
     */
    if (!perfInitialized) {
        perfInitialized = true;
        unlink(outfile);
        char cwd[4096];
        printf("Writing perf profiling data to %s/%s\n",
               getcwd(cwd, sizeof(cwd)), outfile);
    }

    pid_t mainPid = getpid();

    pid_t childPid = fork();
    if (childPid == 0) {
        /* perf record --append --pid $mainPID --output=$outfile $MOZ_PROFILE_PERF_FLAGS */

        char mainPidStr[16];
        snprintf(mainPidStr, sizeof(mainPidStr), "%d", mainPid);
        const char* defaultArgs[] = {"perf", "record", "--append",
                                     "--pid", mainPidStr, "--output", outfile};

        Vector<const char*, 0, SystemAllocPolicy> args;
        args.append(defaultArgs, ArrayLength(defaultArgs));

        const char* flags = getenv("MOZ_PROFILE_PERF_FLAGS");
        if (!flags) {
            flags = "--call-graph";
        }

        char* flags2 = (char*)js_malloc(strlen(flags) + 1);
        if (!flags2)
            return false;
        strcpy(flags2, flags);

        // Split |flags2| on spaces.  (Don't bother to free it -- we're going to
        // exec anyway.)
        char* toksave;
        char* tok = strtok_r(flags2, " ", &toksave);
        while (tok) {
            args.append(tok);
            tok = strtok_r(nullptr, " ", &toksave);
        }

        args.append((char*) nullptr);

        execvp("perf", const_cast<char**>(args.begin()));

        /* Reached only if execlp fails. */
        fprintf(stderr, "Unable to start perf.\n");
        exit(1);
    }
    else if (childPid > 0) {
        perfPid = childPid;

        /* Give perf a chance to warm up. */
        usleep(500 * 1000);
        return true;
    }
    else {
        UnsafeError("js_StartPerf: fork() failed\n");
        return false;
    }
}

bool js_StopPerf()
{
    if (perfPid == 0) {
        UnsafeError("js_StopPerf: perf is not running.\n");
        return true;
    }

    if (kill(perfPid, SIGINT)) {
        UnsafeError("js_StopPerf: kill failed\n");

        // Try to reap the process anyway.
        waitpid(perfPid, nullptr, WNOHANG);
    }
    else {
        waitpid(perfPid, nullptr, 0);
    }

    perfPid = 0;
    return true;
}

#endif /* __linux__ */