Add m-esr52 at 52.6.0

6 files changed, 895 insertions, 0 deletions

diff --git a/tools/jprof/stub/Makefile.in b/tools/jprof/stub/Makefile.in
new file mode 100644
index 000000000..8e6b6b8f8
--- /dev/null
+++ b/tools/jprof/stub/Makefile.in
@@ -0,0 +1,8 @@
+#! gmake
+#
+# 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/.
+
+# override optimization
+MOZ_OPTIMIZE_FLAGS = -fno-omit-frame-pointer
diff --git a/tools/jprof/stub/config.h b/tools/jprof/stub/config.h
new file mode 100644
index 000000000..d43ffcaa6
--- /dev/null
+++ b/tools/jprof/stub/config.h
@@ -0,0 +1,18 @@
+/* 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/. */
+
+#ifndef config_h___
+#define config_h___
+
+#define MAX_STACK_CRAWL 500
+#define M_LOGFILE "jprof-log"
+#define M_MAPFILE "jprof-map"
+
+#if defined(linux) || defined(NTO)
+#define USE_BFD
+#undef NEED_WRAPPERS
+
+#endif /* linux */
+
+#endif /* config_h___ */
diff --git a/tools/jprof/stub/jprof.h b/tools/jprof/stub/jprof.h
new file mode 100644
index 000000000..5ee99279c
--- /dev/null
+++ b/tools/jprof/stub/jprof.h
@@ -0,0 +1,17 @@
+/* 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/. */
+
+#ifndef jprof_h___
+#define jprof_h___
+#include "nscore.h"
+
+#ifdef _IMPL_JPPROF_API
+#define JPROF_API(type) NS_EXPORT_(type)
+#else
+#define JPROF_API(type) NS_IMPORT_(type)
+#endif
+
+JPROF_API(void) setupProfilingStuff(void);
+
+#endif /* jprof_h___ */
diff --git a/tools/jprof/stub/libmalloc.cpp b/tools/jprof/stub/libmalloc.cpp
new file mode 100644
index 000000000..2da2a37b3
--- /dev/null
+++ b/tools/jprof/stub/libmalloc.cpp
@@ -0,0 +1,790 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+// vim:cindent:sw=4:et:ts=8:
+/* 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/. */
+
+// The linux glibc hides part of sigaction if _POSIX_SOURCE is defined
+#if defined(linux)
+#undef _POSIX_SOURCE
+#undef _SVID_SOURCE
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#endif
+
+#include <errno.h>
+#if defined(linux)
+#include <linux/rtc.h>
+#include <pthread.h>
+#endif
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <ucontext.h>
+#include <execinfo.h>
+
+#include "libmalloc.h"
+#include "jprof.h"
+#include <string.h>
+#include <errno.h>
+#include <dlfcn.h>
+
+// Must define before including jprof.h
+void *moz_xmalloc(size_t size)
+{
+    return malloc(size);
+}
+
+void moz_xfree(void *mem)
+{
+    free(mem);
+}
+
+#ifdef NTO
+#include <sys/link.h>
+extern r_debug _r_debug;
+#else
+#include <link.h>
+#endif
+
+#define USE_GLIBC_BACKTRACE 1
+// To debug, use #define JPROF_STATIC
+#define JPROF_STATIC static
+
+static int gLogFD = -1;
+static pthread_t main_thread;
+
+static bool gIsSlave = false;
+static int gFilenamePID;
+
+static void startSignalCounter(unsigned long millisec);
+static int enableRTCSignals(bool enable);
+
+
+//----------------------------------------------------------------------
+// replace use of atexit()
+
+static void DumpAddressMap();
+
+struct JprofShutdown {
+    JprofShutdown() {}
+    ~JprofShutdown() {
+        DumpAddressMap();
+    }
+};
+
+static void RegisterJprofShutdown() {
+    // This instanciates the dummy class above, and will trigger the class
+    // destructor when libxul is unloaded. This is equivalent to atexit(),
+    // but gracefully handles dlclose().
+    static JprofShutdown t;
+}
+
+#if defined(i386) || defined(_i386) || defined(__x86_64__)
+JPROF_STATIC void CrawlStack(malloc_log_entry* me,
+                             void* stack_top, void* top_instr_ptr)
+{
+#if USE_GLIBC_BACKTRACE
+    // This probably works on more than x86!  But we need a way to get the
+    // top instruction pointer, which is kindof arch-specific
+    void *array[500];
+    int cnt, i;
+    u_long numpcs = 0;
+
+    // This is from glibc.  A more generic version might use
+    // libunwind and/or CaptureStackBackTrace() on Windows
+    cnt = backtrace(&array[0],sizeof(array)/sizeof(array[0]));
+
+    // StackHook->JprofLog->CrawlStack
+    // Then we have sigaction, which replaced top_instr_ptr
+    array[3] = top_instr_ptr;
+    for (i = 3; i < cnt; i++)
+    {
+        me->pcs[numpcs++] = (char *) array[i];
+    }
+    me->numpcs = numpcs;
+
+#else
+  // original code - this breaks on many platforms
+  void **bp;
+#if defined(__i386)
+  __asm__( "movl %%ebp, %0" : "=g"(bp));
+#elif defined(__x86_64__)
+  __asm__( "movq %%rbp, %0" : "=g"(bp));
+#else
+  // It would be nice if this worked uniformly, but at least on i386 and
+  // x86_64, it stopped working with gcc 4.1, because it points to the
+  // end of the saved registers instead of the start.
+  bp = __builtin_frame_address(0);
+#endif
+  u_long numpcs = 0;
+  bool tracing = false;
+
+  me->pcs[numpcs++] = (char*) top_instr_ptr;
+
+  while (numpcs < MAX_STACK_CRAWL) {
+    void** nextbp = (void**) *bp++;
+    void* pc = *bp;
+    if (nextbp < bp) {
+      break;
+    }
+    if (tracing) {
+      // Skip the signal handling.
+      me->pcs[numpcs++] = (char*) pc;
+    }
+    else if (pc == top_instr_ptr) {
+      tracing = true;
+    }
+    bp = nextbp;
+  }
+  me->numpcs = numpcs;
+#endif
+}
+#endif
+
+//----------------------------------------------------------------------
+
+static int rtcHz;
+static int rtcFD = -1;
+static bool circular = false;
+
+#if defined(linux) || defined(NTO)
+static void DumpAddressMap()
+{
+  // Turn off the timer so we don't get interrupts during shutdown
+#if defined(linux)
+  if (rtcHz) {
+    enableRTCSignals(false);
+  } else
+#endif
+  {
+    startSignalCounter(0);
+  }
+
+  char filename[2048];
+  if (gIsSlave)
+    snprintf(filename, sizeof(filename), "%s-%d", M_MAPFILE, gFilenamePID);
+  else
+    snprintf(filename, sizeof(filename), "%s", M_MAPFILE);
+
+  int mfd = open(filename, O_CREAT|O_WRONLY|O_TRUNC, 0666);
+  if (mfd >= 0) {
+    malloc_map_entry mme;
+    link_map* map = _r_debug.r_map;
+    while (nullptr != map) {
+      if (map->l_name && *map->l_name) {
+	mme.nameLen = strlen(map->l_name);
+	mme.address = map->l_addr;
+	write(mfd, &mme, sizeof(mme));
+	write(mfd, map->l_name, mme.nameLen);
+#if 0
+	write(1, map->l_name, mme.nameLen);
+	write(1, "\n", 1);
+#endif
+      }
+      map = map->l_next;
+    }
+    close(mfd);
+  }
+}
+#endif
+
+static bool was_paused = true;
+
+JPROF_STATIC void JprofBufferDump();
+JPROF_STATIC void JprofBufferClear();
+
+static void ClearProfilingHook(int signum)
+{
+    if (circular) {
+        JprofBufferClear();
+        puts("Jprof: cleared circular buffer.");
+    }
+}
+
+static void EndProfilingHook(int signum)
+{
+    if (circular)
+        JprofBufferDump();
+
+    DumpAddressMap();
+    was_paused = true;
+    puts("Jprof: profiling paused.");
+}
+
+
+
+//----------------------------------------------------------------------
+// proper usage would be a template, including the function to find the
+// size of an entry, or include a size header explicitly to each entry.
+#if defined(linux)
+#define DUMB_LOCK()   pthread_mutex_lock(&mutex);
+#define DUMB_UNLOCK() pthread_mutex_unlock(&mutex);
+#else
+#define DUMB_LOCK()   FIXME()
+#define DUMB_UNLOCK() FIXME()
+#endif
+
+
+class DumbCircularBuffer
+{
+public:
+    DumbCircularBuffer(size_t init_buffer_size) {
+        used = 0;
+        buffer_size = init_buffer_size;
+        buffer = (unsigned char *) malloc(buffer_size);
+        head = tail = buffer;
+
+#if defined(linux)
+        pthread_mutexattr_t mAttr;
+        pthread_mutexattr_settype(&mAttr, PTHREAD_MUTEX_RECURSIVE_NP);
+        pthread_mutex_init(&mutex, &mAttr);
+        pthread_mutexattr_destroy(&mAttr);
+#endif
+    }
+    ~DumbCircularBuffer() {
+        free(buffer);
+#if defined(linux)
+        pthread_mutex_destroy (&mutex);
+#endif
+    }
+
+    void clear() {
+        DUMB_LOCK();
+        head = tail;
+        used = 0;
+        DUMB_UNLOCK();
+    }
+
+    bool empty() {
+        return head == tail;
+    }
+
+    size_t space_available() {
+        size_t result;
+        DUMB_LOCK();
+        if (tail > head)
+            result = buffer_size - (tail-head) - 1;
+        else
+            result = head-tail - 1;
+        DUMB_UNLOCK();
+        return result;
+    }
+
+    void drop(size_t size) {
+        // assumes correctness!
+        DUMB_LOCK();
+        head += size;
+        if (head >= &buffer[buffer_size])
+            head -= buffer_size;
+        used--;
+        DUMB_UNLOCK();
+    }
+
+    bool insert(void *data, size_t size) {
+        // can fail if not enough space in the entire buffer
+        DUMB_LOCK();
+        if (space_available() < size)
+            return false;
+
+        size_t max_without_wrap = &buffer[buffer_size] - tail;
+        size_t initial = size > max_without_wrap ? max_without_wrap : size;
+#if DEBUG_CIRCULAR
+        fprintf(stderr,"insert(%d): max_without_wrap %d, size %d, initial %d\n",used,max_without_wrap,size,initial);
+#endif
+        memcpy(tail,data,initial);
+        tail += initial;
+        data = ((char *)data)+initial;
+        size -= initial;
+        if (size != 0) {
+#if DEBUG_CIRCULAR
+            fprintf(stderr,"wrapping by %d bytes\n",size);
+#endif
+            memcpy(buffer,data,size);
+            tail = &(((unsigned char *)buffer)[size]);
+        }
+            
+        used++;
+        DUMB_UNLOCK();
+
+        return true;
+    }
+
+    // for external access to the buffer (saving)
+    void lock() {
+        DUMB_LOCK();
+    }
+
+    void unlock() {
+        DUMB_UNLOCK();
+    }
+
+    // XXX These really shouldn't be public...
+    unsigned char *head;
+    unsigned char *tail;
+    unsigned int used;
+    unsigned char *buffer;
+    size_t buffer_size;
+
+private:
+    pthread_mutex_t mutex;
+};
+
+class DumbCircularBuffer *JprofBuffer;
+
+JPROF_STATIC void
+JprofBufferInit(size_t size)
+{
+    JprofBuffer = new DumbCircularBuffer(size);
+}
+
+JPROF_STATIC void
+JprofBufferClear()
+{
+    fprintf(stderr,"Told to clear JPROF circular buffer\n");
+    JprofBuffer->clear();
+}
+
+JPROF_STATIC size_t
+JprofEntrySizeof(malloc_log_entry *me)
+{
+    return offsetof(malloc_log_entry, pcs) + me->numpcs*sizeof(char*);
+}
+
+JPROF_STATIC void
+JprofBufferAppend(malloc_log_entry *me)
+{
+    size_t size = JprofEntrySizeof(me);
+
+    do {
+        while (JprofBuffer->space_available() < size &&
+               JprofBuffer->used > 0) {
+#if DEBUG_CIRCULAR
+            fprintf(stderr,"dropping entry: %d in use, %d free, need %d, size_to_free = %d\n",
+                    JprofBuffer->used,JprofBuffer->space_available(),size,JprofEntrySizeof((malloc_log_entry *) JprofBuffer->head));
+#endif
+            JprofBuffer->drop(JprofEntrySizeof((malloc_log_entry *) JprofBuffer->head));
+        }
+        if (JprofBuffer->space_available() < size)
+            return;
+
+    } while (!JprofBuffer->insert(me,size));
+}
+
+JPROF_STATIC void
+JprofBufferDump()
+{
+    JprofBuffer->lock();
+#if DEBUG_CIRCULAR
+    fprintf(stderr,"dumping JP_CIRCULAR buffer, %d of %d bytes\n",
+            JprofBuffer->tail > JprofBuffer->head ? 
+              JprofBuffer->tail - JprofBuffer->head :
+              JprofBuffer->buffer_size + JprofBuffer->tail - JprofBuffer->head,
+            JprofBuffer->buffer_size);
+#endif
+    if (JprofBuffer->tail >= JprofBuffer->head) {
+        write(gLogFD, JprofBuffer->head, JprofBuffer->tail - JprofBuffer->head);
+    } else {
+        write(gLogFD, JprofBuffer->head, &(JprofBuffer->buffer[JprofBuffer->buffer_size]) - JprofBuffer->head);
+        write(gLogFD, JprofBuffer->buffer, JprofBuffer->tail - JprofBuffer->buffer);
+    }
+    JprofBuffer->clear();
+    JprofBuffer->unlock();
+}
+
+//----------------------------------------------------------------------
+
+JPROF_STATIC void
+JprofLog(u_long aTime, void* stack_top, void* top_instr_ptr)
+{
+  // Static is simply to make debugging tolerable
+  static malloc_log_entry me;
+
+  me.delTime = aTime;
+  me.thread = syscall(SYS_gettid); //gettid();
+  if (was_paused) {
+      me.flags = JP_FIRST_AFTER_PAUSE;
+      was_paused = 0;
+  } else {
+      me.flags = 0;
+  }
+
+  CrawlStack(&me, stack_top, top_instr_ptr);
+
+#ifndef NTO
+  if (circular) {
+      JprofBufferAppend(&me);
+  } else {
+      write(gLogFD, &me, JprofEntrySizeof(&me));
+  }
+#else
+      printf("Neutrino is missing the pcs member of malloc_log_entry!! \n");
+#endif
+}
+
+static int realTime;
+
+/* Lets interrupt at 10 Hz.  This is so my log files don't get too large.
+ * This can be changed to a faster value latter.  This timer is not
+ * programmed to reset, even though it is capable of doing so.  This is
+ * to keep from getting interrupts from inside of the handler.
+*/
+static void startSignalCounter(unsigned long millisec)
+{
+    struct itimerval tvalue;
+
+    tvalue.it_interval.tv_sec = 0;
+    tvalue.it_interval.tv_usec = 0;
+    tvalue.it_value.tv_sec = millisec/1000;
+    tvalue.it_value.tv_usec = (millisec%1000)*1000;
+
+    if (realTime) {
+        setitimer(ITIMER_REAL, &tvalue, nullptr);
+    } else {
+        setitimer(ITIMER_PROF, &tvalue, nullptr);
+    }
+}
+
+static long timerMilliSec = 50;
+
+#if defined(linux)
+static int setupRTCSignals(int hz, struct sigaction *sap)
+{
+    /* global */ rtcFD = open("/dev/rtc", O_RDONLY);
+    if (rtcFD < 0) {
+        perror("JPROF_RTC setup: open(\"/dev/rtc\", O_RDONLY)");
+        return 0;
+    }
+
+    if (sigaction(SIGIO, sap, nullptr) == -1) {
+        perror("JPROF_RTC setup: sigaction(SIGIO)");
+        return 0;
+    }
+
+    if (ioctl(rtcFD, RTC_IRQP_SET, hz) == -1) {
+        perror("JPROF_RTC setup: ioctl(/dev/rtc, RTC_IRQP_SET, $JPROF_RTC_HZ)");
+        return 0;
+    }
+
+    if (ioctl(rtcFD, RTC_PIE_ON, 0) == -1) {
+        perror("JPROF_RTC setup: ioctl(/dev/rtc, RTC_PIE_ON)");
+        return 0;
+    }
+
+    if (fcntl(rtcFD, F_SETSIG, 0) == -1) {
+        perror("JPROF_RTC setup: fcntl(/dev/rtc, F_SETSIG, 0)");
+        return 0;
+    }
+
+    if (fcntl(rtcFD, F_SETOWN, getpid()) == -1) {
+        perror("JPROF_RTC setup: fcntl(/dev/rtc, F_SETOWN, getpid())");
+        return 0;
+    }
+
+    return 1;
+}
+
+static int enableRTCSignals(bool enable)
+{
+    static bool enabled = false;
+    if (enabled == enable) {
+        return 0;
+    }
+    enabled = enable;
+    
+    int flags = fcntl(rtcFD, F_GETFL);
+    if (flags < 0) {
+        perror("JPROF_RTC setup: fcntl(/dev/rtc, F_GETFL)");
+        return 0;
+    }
+
+    if (enable) {
+        flags |= FASYNC;
+    } else {
+        flags &= ~FASYNC;
+    }
+
+    if (fcntl(rtcFD, F_SETFL, flags) == -1) {
+        if (enable) {
+            perror("JPROF_RTC setup: fcntl(/dev/rtc, F_SETFL, flags | FASYNC)");
+        } else {
+            perror("JPROF_RTC setup: fcntl(/dev/rtc, F_SETFL, flags & ~FASYNC)");
+        }            
+        return 0;
+    }
+
+    return 1;
+}
+#endif
+
+JPROF_STATIC void StackHook(
+int signum,
+siginfo_t *info,
+void *ucontext)
+{
+    static struct timeval tFirst;
+    static int first=1;
+    size_t millisec = 0;
+
+#if defined(linux)
+    if (rtcHz && pthread_self() != main_thread) {
+      // Only collect stack data on the main thread, for now.
+      return;
+    }
+#endif
+
+    if(first && !(first=0)) {
+        puts("Jprof: received first signal");
+#if defined(linux)
+        if (rtcHz) {
+            enableRTCSignals(true);
+        } else
+#endif
+        {
+            gettimeofday(&tFirst, 0);
+            millisec = 0;
+        }
+    } else {
+#if defined(linux)
+        if (rtcHz) {
+            enableRTCSignals(true);
+        } else
+#endif
+        {
+            struct timeval tNow;
+            gettimeofday(&tNow, 0);
+            double usec = 1e6*(tNow.tv_sec - tFirst.tv_sec);
+            usec += (tNow.tv_usec - tFirst.tv_usec);
+            millisec = static_cast<size_t>(usec*1e-3);
+        }
+    }
+
+    gregset_t &gregs = ((ucontext_t*)ucontext)->uc_mcontext.gregs;
+#ifdef __x86_64__
+    JprofLog(millisec, (void*)gregs[REG_RSP], (void*)gregs[REG_RIP]);
+#else
+    JprofLog(millisec, (void*)gregs[REG_ESP], (void*)gregs[REG_EIP]);
+#endif
+
+    if (!rtcHz)
+        startSignalCounter(timerMilliSec);
+}
+
+NS_EXPORT_(void) setupProfilingStuff(void)
+{
+    static int gFirstTime = 1;
+    char filename[2048]; // XXX fix
+
+    if(gFirstTime && !(gFirstTime=0)) {
+	int  startTimer = 1;
+	int  doNotStart = 1;
+	int  firstDelay = 0;
+        int  append = O_TRUNC;
+        char *tst  = getenv("JPROF_FLAGS");
+
+	/* Options from JPROF_FLAGS environment variable:
+	 *   JP_DEFER  -> Wait for a SIGPROF (or SIGALRM, if JP_REALTIME
+	 *               is set) from userland before starting
+	 *               to generate them internally
+	 *   JP_START  -> Install the signal handler
+	 *   JP_PERIOD -> Time between profiler ticks
+	 *   JP_FIRST  -> Extra delay before starting
+	 *   JP_REALTIME -> Take stack traces in intervals of real time
+	 *               rather than time used by the process (and the
+	 *               system for the process).  This is useful for
+	 *               finding time spent by the X server.
+         *   JP_APPEND -> Append to jprof-log rather than overwriting it.
+         *               This is somewhat risky since it depends on the
+         *               address map staying constant across multiple runs.
+         *   JP_FILENAME -> base filename to use when saving logs.  Note that
+         *               this does not affect the mapfile.
+         *   JP_CIRCULAR -> use a circular buffer of size N, write/clear on SIGUSR1
+         *
+         * JPROF_SLAVE is set if this is not the first process.
+	*/
+
+        circular = false;
+
+	if(tst) {
+	    if(strstr(tst, "JP_DEFER"))
+	    {
+		doNotStart = 0;
+		startTimer = 0;
+	    }
+	    if(strstr(tst, "JP_START")) doNotStart = 0;
+	    if(strstr(tst, "JP_REALTIME")) realTime = 1;
+	    if(strstr(tst, "JP_APPEND")) append = O_APPEND;
+
+	    char *delay = strstr(tst,"JP_PERIOD=");
+	    if(delay) {
+                double tmp = strtod(delay+strlen("JP_PERIOD="), nullptr);
+                if (tmp>=1e-3) {
+		    timerMilliSec = static_cast<unsigned long>(1000 * tmp);
+                } else {
+                    fprintf(stderr,
+                            "JP_PERIOD of %g less than 0.001 (1ms), using 1ms\n",
+                            tmp);
+                    timerMilliSec = 1;
+                }
+	    }
+
+	    char *circular_op = strstr(tst,"JP_CIRCULAR=");
+	    if(circular_op) {
+                size_t size = atol(circular_op+strlen("JP_CIRCULAR="));
+                if (size < 1000) {
+                    fprintf(stderr,
+                            "JP_CIRCULAR of %lu less than 1000, using 10000\n",
+                            (unsigned long) size);
+                    size = 10000;
+                }
+                JprofBufferInit(size);
+                fprintf(stderr,"JP_CIRCULAR buffer of %lu bytes\n", (unsigned long) size);
+                circular = true;
+	    }
+
+	    char *first = strstr(tst, "JP_FIRST=");
+	    if(first) {
+                firstDelay = atol(first+strlen("JP_FIRST="));
+	    }
+
+            char *rtc = strstr(tst, "JP_RTC_HZ=");
+            if (rtc) {
+#if defined(linux)
+                rtcHz = atol(rtc+strlen("JP_RTC_HZ="));
+                timerMilliSec = 0; /* This makes JP_FIRST work right. */
+                realTime = 1; /* It's the _R_TC and all.  ;) */
+
+#define IS_POWER_OF_TWO(x) (((x) & ((x) - 1)) == 0)
+
+                if (!IS_POWER_OF_TWO(rtcHz) || rtcHz < 2) {
+                    fprintf(stderr, "JP_RTC_HZ must be power of two and >= 2, "
+                            "but %d was provided; using default of 2048\n",
+                            rtcHz);
+                    rtcHz = 2048;
+                }
+#else
+                fputs("JP_RTC_HZ found, but RTC profiling only supported on "
+                      "Linux!\n", stderr);
+                  
+#endif
+            }
+            const char *f = strstr(tst,"JP_FILENAME=");
+            if (f)
+                f = f + strlen("JP_FILENAME=");
+            else
+                f = M_LOGFILE;
+
+            char *is_slave = getenv("JPROF_SLAVE");
+            if (!is_slave)
+                setenv("JPROF_SLAVE","", 0);
+            gIsSlave = !!is_slave;
+
+            gFilenamePID = syscall(SYS_gettid); //gettid();
+            if (is_slave)
+                snprintf(filename,sizeof(filename),"%s-%d",f,gFilenamePID);
+            else
+                snprintf(filename,sizeof(filename),"%s",f);
+
+            // XXX FIX! inherit current capture state!
+	}
+
+	if(!doNotStart) {
+
+	    if(gLogFD<0) {
+		gLogFD = open(filename, O_CREAT | O_WRONLY | append, 0666);
+		if(gLogFD<0) {
+		    fprintf(stderr, "Unable to create " M_LOGFILE);
+		    perror(":");
+		} else {
+		    struct sigaction action;
+		    sigset_t mset;
+
+		    // Dump out the address map when we terminate
+		    RegisterJprofShutdown();
+
+		    main_thread = pthread_self();
+                    //fprintf(stderr,"jprof: main_thread = %u\n",
+                    //        (unsigned int)main_thread);
+
+                    // FIX!  probably should block these against each other
+                    // Very unlikely.
+		    sigemptyset(&mset);
+		    action.sa_handler = nullptr;
+		    action.sa_sigaction = StackHook;
+		    action.sa_mask  = mset;
+		    action.sa_flags = SA_RESTART | SA_SIGINFO;
+#if defined(linux)
+                    if (rtcHz) {
+                        if (!setupRTCSignals(rtcHz, &action)) {
+                            fputs("jprof: Error initializing RTC, NOT "
+                                  "profiling\n", stderr);
+                            return;
+                        }
+                    }
+
+                    if (!rtcHz || firstDelay != 0)
+#endif
+                    {
+                        if (realTime) {
+                            sigaction(SIGALRM, &action, nullptr);
+                        }
+                    }
+                    // enable PROF in all cases to simplify JP_DEFER/pause/restart
+                    sigaction(SIGPROF, &action, nullptr);
+
+		    // make it so a SIGUSR1 will stop the profiling
+		    // Note:  It currently does not close the logfile.
+		    // This could be configurable (so that it could
+		    // later be reopened).
+
+		    struct sigaction stop_action;
+		    stop_action.sa_handler = EndProfilingHook;
+		    stop_action.sa_mask  = mset;
+		    stop_action.sa_flags = SA_RESTART;
+		    sigaction(SIGUSR1, &stop_action, nullptr);
+
+		    // make it so a SIGUSR2 will clear the circular buffer
+
+		    stop_action.sa_handler = ClearProfilingHook;
+		    stop_action.sa_mask  = mset;
+		    stop_action.sa_flags = SA_RESTART;
+		    sigaction(SIGUSR2, &stop_action, nullptr);
+
+                    printf("Jprof: Initialized signal handler and set "
+                           "timer for %lu %s, %d s "
+                           "initial delay\n",
+                           rtcHz ? rtcHz : timerMilliSec, 
+                           rtcHz ? "Hz" : "ms",
+                           firstDelay);
+
+		    if(startTimer) {
+#if defined(linux)
+                        /* If we have an initial delay we can just use
+                           startSignalCounter to set up a timer to fire the
+                           first stackHook after that delay.  When that happens
+                           we'll go and switch to RTC profiling. */
+                        if (rtcHz && firstDelay == 0) {
+                            puts("Jprof: enabled RTC signals");
+                            enableRTCSignals(true);
+                        } else
+#endif
+                        {
+                            puts("Jprof: started timer");
+                            startSignalCounter(firstDelay*1000 + timerMilliSec);
+                        }
+		    }
+		}
+	    }
+	}
+    } else {
+        printf("setupProfilingStuff() called multiple times\n");
+    }
+}
diff --git a/tools/jprof/stub/libmalloc.h b/tools/jprof/stub/libmalloc.h
new file mode 100644
index 000000000..8b29bf889
--- /dev/null
+++ b/tools/jprof/stub/libmalloc.h
@@ -0,0 +1,45 @@
+/* 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/. */
+
+#ifndef libmalloc_h___
+#define libmalloc_h___
+
+#include <sys/types.h>
+#include <malloc.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "config.h"
+
+typedef unsigned long u_long;
+
+// For me->flags
+#define JP_FIRST_AFTER_PAUSE 1
+
+// Format of a jprof log entry. This is what's written out to the
+// "jprof-log" file.
+// It's called malloc_log_entry because the history of jprof is that
+// it's a modified version of tracemalloc.
+struct malloc_log_entry {
+  u_long delTime;
+  u_long numpcs;
+  unsigned int flags;
+  int thread;
+  char* pcs[MAX_STACK_CRAWL];
+};
+
+// Format of a malloc map entry; after this struct is nameLen+1 bytes of
+// name data.
+struct malloc_map_entry {
+  u_long nameLen;
+  u_long address;		// base address
+};
+
+#ifdef __cplusplus
+} /* end of extern "C" */
+#endif
+
+#endif /* libmalloc_h___ */
diff --git a/tools/jprof/stub/moz.build b/tools/jprof/stub/moz.build
new file mode 100644
index 000000000..a2f514a54
--- /dev/null
+++ b/tools/jprof/stub/moz.build
@@ -0,0 +1,17 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+EXPORTS += [
+    'jprof.h',
+]
+
+SOURCES += [
+    'libmalloc.cpp',
+]
+
+SharedLibrary('jprof')
+
+DEFINES['_IMPL_JPROF_API'] = True