path: root/0004_hurd.patch

Description: hurd-i386 support
 https://bugs.debian.org/747246
Author: Svante Signell <svante.signell@gmail.com>
Acked-By: Jérémy Lal <kapouer@melix.org>
Last-Update: 2014-05-06

---
 src/platform-gnu.cc | 890 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 tools/gyp/v8.gyp    |  11 +
 2 files changed, 901 insertions(+)
 create mode 100644 src/platform-gnu.cc

--- /dev/null
+++ b/src/platform-gnu.cc
@@ -0,0 +1,890 @@
+// Copyright 2012 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Platform specific code for GNU/Hurd goes here. For the POSIX comaptible parts
+// the implementation is in platform-posix.cc.
+
+#include <pthread.h>
+#include <semaphore.h>
+#include <signal.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sys/types.h>
+#include <sys/ucontext.h>
+#include <stdlib.h>
+
+#include <sys/types.h>  // mmap & munmap
+#include <sys/mman.h>   // mmap & munmap
+#include <sys/stat.h>   // open
+#include <sys/fcntl.h>  // open
+#include <unistd.h>     // getpagesize
+// If you don't have execinfo.h then you need devel/libexecinfo from ports.
+#include <execinfo.h>   // backtrace, backtrace_symbols
+#include <strings.h>    // index
+#include <errno.h>
+#include <stdarg.h>
+#include <limits.h>
+
+#undef MAP_TYPE
+
+#include "v8.h"
+#include "v8threads.h"
+
+#include "platform-posix.h"
+#include "platform.h"
+#include "vm-state-inl.h"
+
+#ifndef MAP_NORESERVE
+#define MAP_NORESERVE 0
+#endif
+
+namespace v8 {
+namespace internal {
+
+// 0 is never a valid thread id on GNU/Hurd
+static const pthread_t kNoThread = (pthread_t) 0;
+
+
+double ceiling(double x) {
+  return ceil(x);
+}
+
+
+static Mutex* limit_mutex = NULL;
+
+
+void OS::PostSetUp() {
+  POSIXPostSetUp();
+}
+
+
+void OS::ReleaseStore(volatile AtomicWord* ptr, AtomicWord value) {
+  __asm__ __volatile__("" : : : "memory");
+  *ptr = value;
+}
+
+
+uint64_t OS::CpuFeaturesImpliedByPlatform() {
+  return 0;  // GNU/Hurd runs on anything.
+}
+
+
+int OS::ActivationFrameAlignment() {
+  // 16 byte alignment on GNU/Hurd
+  return 16;
+}
+
+
+const char* OS::LocalTimezone(double time) {
+  if (isnan(time)) return "";
+  time_t tv = static_cast<time_t>(floor(time/msPerSecond));
+  struct tm* t = localtime(&tv);
+  if (NULL == t) return "";
+  return t->tm_zone;
+}
+
+
+double OS::LocalTimeOffset() {
+  time_t tv = time(NULL);
+  struct tm* t = localtime(&tv);
+  // tm_gmtoff includes any daylight savings offset, so subtract it.
+  return static_cast<double>(t->tm_gmtoff * msPerSecond -
+                             (t->tm_isdst > 0 ? 3600 * msPerSecond : 0));
+}
+
+
+// We keep the lowest and highest addresses mapped as a quick way of
+// determining that pointers are outside the heap (used mostly in assertions
+// and verification).  The estimate is conservative, i.e., not all addresses in
+// 'allocated' space are actually allocated to our heap.  The range is
+// [lowest, highest), inclusive on the low and and exclusive on the high end.
+static void* lowest_ever_allocated = reinterpret_cast<void*>(-1);
+static void* highest_ever_allocated = reinterpret_cast<void*>(0);
+
+
+static void UpdateAllocatedSpaceLimits(void* address, int size) {
+  ASSERT(limit_mutex != NULL);
+  ScopedLock lock(limit_mutex);
+
+  lowest_ever_allocated = Min(lowest_ever_allocated, address);
+  highest_ever_allocated =
+      Max(highest_ever_allocated,
+          reinterpret_cast<void*>(reinterpret_cast<char*>(address) + size));
+}
+
+
+bool OS::IsOutsideAllocatedSpace(void* address) {
+  return address < lowest_ever_allocated || address >= highest_ever_allocated;
+}
+
+
+size_t OS::AllocateAlignment() {
+  return getpagesize();
+}
+
+
+void* OS::Allocate(const size_t requested,
+                   size_t* allocated,
+                   bool executable) {
+  const size_t msize = RoundUp(requested, getpagesize());
+  int prot = PROT_READ | PROT_WRITE | (executable ? PROT_EXEC : 0);
+  void* mbase = mmap(NULL, msize, prot, MAP_PRIVATE | MAP_ANON, -1, 0);
+
+  if (mbase == MAP_FAILED) {
+    LOG(ISOLATE, StringEvent("OS::Allocate", "mmap failed"));
+    return NULL;
+  }
+  *allocated = msize;
+  UpdateAllocatedSpaceLimits(mbase, msize);
+  return mbase;
+}
+
+
+void OS::Free(void* buf, const size_t length) {
+  // TODO(1240712): munmap has a return value which is ignored here.
+  int result = munmap(buf, length);
+  USE(result);
+  ASSERT(result == 0);
+}
+
+
+void OS::Sleep(int milliseconds) {
+  unsigned int ms = static_cast<unsigned int>(milliseconds);
+  usleep(1000 * ms);
+}
+
+
+void OS::Abort() {
+  // Redirect to std abort to signal abnormal program termination.
+  abort();
+}
+
+
+void OS::DebugBreak() {
+#if (defined(__arm__) || defined(__thumb__))
+# if defined(CAN_USE_ARMV5_INSTRUCTIONS)
+  asm("bkpt 0");
+# endif
+#else
+  asm("int $3");
+#endif
+}
+
+
+class PosixMemoryMappedFile : public OS::MemoryMappedFile {
+ public:
+  PosixMemoryMappedFile(FILE* file, void* memory, int size)
+    : file_(file), memory_(memory), size_(size) { }
+  virtual ~PosixMemoryMappedFile();
+  virtual void* memory() { return memory_; }
+  virtual int size() { return size_; }
+ private:
+  FILE* file_;
+  void* memory_;
+  int size_;
+};
+
+
+OS::MemoryMappedFile* OS::MemoryMappedFile::open(const char* name) {
+  FILE* file = fopen(name, "r+");
+  if (file == NULL) return NULL;
+
+  fseek(file, 0, SEEK_END);
+  int size = ftell(file);
+
+  void* memory =
+      mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fileno(file), 0);
+  return new PosixMemoryMappedFile(file, memory, size);
+}
+
+
+OS::MemoryMappedFile* OS::MemoryMappedFile::create(const char* name, int size,
+    void* initial) {
+  FILE* file = fopen(name, "w+");
+  if (file == NULL) return NULL;
+  int result = fwrite(initial, size, 1, file);
+  if (result < 1) {
+    fclose(file);
+    return NULL;
+  }
+  void* memory =
+      mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fileno(file), 0);
+  return new PosixMemoryMappedFile(file, memory, size);
+}
+
+
+PosixMemoryMappedFile::~PosixMemoryMappedFile() {
+  if (memory_) munmap(memory_, size_);
+  fclose(file_);
+}
+
+
+static unsigned StringToLong(char* buffer) {
+  return static_cast<unsigned>(strtol(buffer, NULL, 16));  // NOLINT
+}
+
+
+void OS::LogSharedLibraryAddresses() {
+  static const int MAP_LENGTH = 1024;
+  int fd = open("/proc/self/maps", O_RDONLY);
+  if (fd < 0) return;
+  while (true) {
+    char addr_buffer[11];
+    addr_buffer[0] = '0';
+    addr_buffer[1] = 'x';
+    addr_buffer[10] = 0;
+    int result = read(fd, addr_buffer + 2, 8);
+    if (result < 8) break;
+    unsigned start = StringToLong(addr_buffer);
+    result = read(fd, addr_buffer + 2, 1);
+    if (result < 1) break;
+    if (addr_buffer[2] != '-') break;
+    result = read(fd, addr_buffer + 2, 8);
+    if (result < 8) break;
+    unsigned end = StringToLong(addr_buffer);
+    char buffer[MAP_LENGTH];
+    int bytes_read = -1;
+    do {
+      bytes_read++;
+      if (bytes_read >= MAP_LENGTH - 1)
+        break;
+      result = read(fd, buffer + bytes_read, 1);
+      if (result < 1) break;
+    } while (buffer[bytes_read] != '\n');
+    buffer[bytes_read] = 0;
+    // Ignore mappings that are not executable.
+    if (buffer[3] != 'x') continue;
+    char* start_of_path = index(buffer, '/');
+    // There may be no filename in this line.  Skip to next.
+    if (start_of_path == NULL) continue;
+    buffer[bytes_read] = 0;
+    LOG(i::Isolate::Current(), SharedLibraryEvent(start_of_path, start, end));
+  }
+  close(fd);
+}
+
+
+void OS::SignalCodeMovingGC() {
+}
+
+
+int OS::StackWalk(Vector<OS::StackFrame> frames) {
+  int frames_size = frames.length();
+  ScopedVector<void*> addresses(frames_size);
+
+  int frames_count = backtrace(addresses.start(), frames_size);
+
+  char** symbols = backtrace_symbols(addresses.start(), frames_count);
+  if (symbols == NULL) {
+    return kStackWalkError;
+  }
+
+  for (int i = 0; i < frames_count; i++) {
+    frames[i].address = addresses[i];
+    // Format a text representation of the frame based on the information
+    // available.
+    SNPrintF(MutableCStrVector(frames[i].text, kStackWalkMaxTextLen),
+             "%s",
+             symbols[i]);
+    // Make sure line termination is in place.
+    frames[i].text[kStackWalkMaxTextLen - 1] = '\0';
+  }
+
+  free(symbols);
+
+  return frames_count;
+}
+
+
+// Constants used for mmap.
+static const int kMmapFd = -1;
+static const int kMmapFdOffset = 0;
+
+VirtualMemory::VirtualMemory() : address_(NULL), size_(0) { }
+
+VirtualMemory::VirtualMemory(size_t size) {
+  address_ = ReserveRegion(size);
+  size_ = size;
+}
+
+
+VirtualMemory::VirtualMemory(size_t size, size_t alignment)
+    : address_(NULL), size_(0) {
+  ASSERT(IsAligned(alignment, static_cast<intptr_t>(OS::AllocateAlignment())));
+  size_t request_size = RoundUp(size + alignment,
+                                static_cast<intptr_t>(OS::AllocateAlignment()));
+  void* reservation = mmap(OS::GetRandomMmapAddr(),
+                           request_size,
+                           PROT_NONE,
+                           MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
+                           kMmapFd,
+                           kMmapFdOffset);
+  if (reservation == MAP_FAILED) return;
+
+  Address base = static_cast<Address>(reservation);
+  Address aligned_base = RoundUp(base, alignment);
+  ASSERT_LE(base, aligned_base);
+
+  // Unmap extra memory reserved before and after the desired block.
+  if (aligned_base != base) {
+    size_t prefix_size = static_cast<size_t>(aligned_base - base);
+    OS::Free(base, prefix_size);
+    request_size -= prefix_size;
+  }
+
+  size_t aligned_size = RoundUp(size, OS::AllocateAlignment());
+  ASSERT_LE(aligned_size, request_size);
+
+  if (aligned_size != request_size) {
+    size_t suffix_size = request_size - aligned_size;
+    OS::Free(aligned_base + aligned_size, suffix_size);
+    request_size -= suffix_size;
+  }
+
+  ASSERT(aligned_size == request_size);
+
+  address_ = static_cast<void*>(aligned_base);
+  size_ = aligned_size;
+}
+
+
+VirtualMemory::~VirtualMemory() {
+  if (IsReserved()) {
+    bool result = ReleaseRegion(address(), size());
+    ASSERT(result);
+    USE(result);
+  }
+}
+
+
+bool VirtualMemory::IsReserved() {
+  return address_ != NULL;
+}
+
+
+void VirtualMemory::Reset() {
+  address_ = NULL;
+  size_ = 0;
+}
+
+
+bool VirtualMemory::Commit(void* address, size_t size, bool is_executable) {
+  return CommitRegion(address, size, is_executable);
+}
+
+
+bool VirtualMemory::Uncommit(void* address, size_t size) {
+  return UncommitRegion(address, size);
+}
+
+
+bool VirtualMemory::Guard(void* address) {
+  OS::Guard(address, OS::CommitPageSize());
+  return true;
+}
+
+
+void* VirtualMemory::ReserveRegion(size_t size) {
+  void* result = mmap(OS::GetRandomMmapAddr(),
+                      size,
+                      PROT_NONE,
+                      MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
+                      kMmapFd,
+                      kMmapFdOffset);
+
+  if (result == MAP_FAILED) return NULL;
+
+  return result;
+}
+
+
+bool VirtualMemory::CommitRegion(void* base, size_t size, bool is_executable) {
+  int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
+  if (MAP_FAILED == mmap(base,
+                         size,
+                         prot,
+                         MAP_PRIVATE | MAP_ANON | MAP_FIXED,
+                         kMmapFd,
+                         kMmapFdOffset)) {
+    return false;
+  }
+
+  UpdateAllocatedSpaceLimits(base, size);
+  return true;
+}
+
+
+bool VirtualMemory::UncommitRegion(void* base, size_t size) {
+  return mmap(base,
+              size,
+              PROT_NONE,
+              MAP_PRIVATE | MAP_ANON | MAP_NORESERVE | MAP_FIXED,
+              kMmapFd,
+              kMmapFdOffset) != MAP_FAILED;
+}
+
+
+bool VirtualMemory::ReleaseRegion(void* base, size_t size) {
+  return munmap(base, size) == 0;
+}
+
+
+class Thread::PlatformData : public Malloced {
+ public:
+  pthread_t thread_;  // Thread handle for pthread.
+};
+
+
+Thread::Thread(const Options& options)
+    : data_(new PlatformData),
+      stack_size_(options.stack_size()) {
+  set_name(options.name());
+}
+
+
+Thread::~Thread() {
+  delete data_;
+}
+
+
+static void* ThreadEntry(void* arg) {
+  Thread* thread = reinterpret_cast<Thread*>(arg);
+  // This is also initialized by the first argument to pthread_create() but we
+  // don't know which thread will run first (the original thread or the new
+  // one) so we initialize it here too.
+  thread->data()->thread_ = pthread_self();
+  ASSERT(thread->data()->thread_ != kNoThread);
+  thread->Run();
+  return NULL;
+}
+
+
+void Thread::set_name(const char* name) {
+  strncpy(name_, name, sizeof(name_));
+  name_[sizeof(name_) - 1] = '\0';
+}
+
+
+void Thread::Start() {
+  pthread_attr_t* attr_ptr = NULL;
+  pthread_attr_t attr;
+  if (stack_size_ > 0) {
+    pthread_attr_init(&attr);
+    pthread_attr_setstacksize(&attr, static_cast<size_t>(stack_size_));
+    attr_ptr = &attr;
+  }
+  pthread_create(&data_->thread_, attr_ptr, ThreadEntry, this);
+  ASSERT(data_->thread_ != kNoThread);
+}
+
+
+void Thread::Join() {
+  pthread_join(data_->thread_, NULL);
+}
+
+
+Thread::LocalStorageKey Thread::CreateThreadLocalKey() {
+  pthread_key_t key;
+  int result = pthread_key_create(&key, NULL);
+  USE(result);
+  ASSERT(result == 0);
+  return static_cast<LocalStorageKey>(key);
+}
+
+
+void Thread::DeleteThreadLocalKey(LocalStorageKey key) {
+  pthread_key_t pthread_key = static_cast<pthread_key_t>(key);
+  int result = pthread_key_delete(pthread_key);
+  USE(result);
+  ASSERT(result == 0);
+}
+
+
+void* Thread::GetThreadLocal(LocalStorageKey key) {
+  pthread_key_t pthread_key = static_cast<pthread_key_t>(key);
+  return pthread_getspecific(pthread_key);
+}
+
+
+void Thread::SetThreadLocal(LocalStorageKey key, void* value) {
+  pthread_key_t pthread_key = static_cast<pthread_key_t>(key);
+  pthread_setspecific(pthread_key, value);
+}
+
+
+void Thread::YieldCPU() {
+  sched_yield();
+}
+
+
+class GNUMutex : public Mutex {
+ public:
+  GNUMutex() {
+    pthread_mutexattr_t attrs;
+    int result = pthread_mutexattr_init(&attrs);
+    ASSERT(result == 0);
+    result = pthread_mutexattr_settype(&attrs, PTHREAD_MUTEX_RECURSIVE);
+    ASSERT(result == 0);
+    result = pthread_mutex_init(&mutex_, &attrs);
+    ASSERT(result == 0);
+    USE(result);
+  }
+
+  virtual ~GNUMutex() { pthread_mutex_destroy(&mutex_); }
+
+  virtual int Lock() {
+    int result = pthread_mutex_lock(&mutex_);
+    return result;
+  }
+
+  virtual int Unlock() {
+    int result = pthread_mutex_unlock(&mutex_);
+    return result;
+  }
+
+  virtual bool TryLock() {
+    int result = pthread_mutex_trylock(&mutex_);
+    // Return false if the lock is busy and locking failed.
+    if (result == EBUSY) {
+      return false;
+    }
+    ASSERT(result == 0);  // Verify no other errors.
+    return true;
+  }
+
+ private:
+  pthread_mutex_t mutex_;   // Pthread mutex for POSIX platforms.
+};
+
+
+Mutex* OS::CreateMutex() {
+  return new GNUMutex();
+}
+
+
+class GNUSemaphore : public Semaphore {
+ public:
+  explicit GNUSemaphore(int count) {  sem_init(&sem_, 0, count); }
+  virtual ~GNUSemaphore() { sem_destroy(&sem_); }
+
+  virtual void Wait();
+  virtual bool Wait(int timeout);
+  virtual void Signal() { sem_post(&sem_); }
+ private:
+  sem_t sem_;
+};
+
+
+void GNUSemaphore::Wait() {
+  while (true) {
+    int result = sem_wait(&sem_);
+    if (result == 0) return;  // Successfully got semaphore.
+    CHECK(result == -1 && errno == EINTR);  // Signal caused spurious wakeup.
+  }
+}
+
+
+bool GNUSemaphore::Wait(int timeout) {
+  const long kOneSecondMicros = 1000000;  // NOLINT
+
+  // Split timeout into second and nanosecond parts.
+  struct timeval delta;
+  delta.tv_usec = timeout % kOneSecondMicros;
+  delta.tv_sec = timeout / kOneSecondMicros;
+
+  struct timeval current_time;
+  // Get the current time.
+  if (gettimeofday(&current_time, NULL) == -1) {
+    return false;
+  }
+
+  // Calculate time for end of timeout.
+  struct timeval end_time;
+  timeradd(&current_time, &delta, &end_time);
+
+  struct timespec ts;
+  TIMEVAL_TO_TIMESPEC(&end_time, &ts);
+  while (true) {
+    int result = sem_timedwait(&sem_, &ts);
+    if (result == 0) return true;  // Successfully got semaphore.
+    if (result == -1 && errno == ETIMEDOUT) return false;  // Timeout.
+    CHECK(result == -1 && errno == EINTR);  // Signal caused spurious wakeup.
+  }
+}
+
+
+Semaphore* OS::CreateSemaphore(int count) {
+  return new GNUSemaphore(count);
+}
+
+
+static pthread_t GetThreadID() {
+  pthread_t thread_id = pthread_self();
+  return thread_id;
+}
+
+
+class Sampler::PlatformData : public Malloced {
+ public:
+  PlatformData() : vm_tid_(GetThreadID()) {}
+
+  pthread_t vm_tid() const { return vm_tid_; }
+
+ private:
+  pthread_t vm_tid_;
+};
+
+
+static void ProfilerSignalHandler(int signal, siginfo_t* info, void* context) {
+  USE(info);
+  if (signal != SIGPROF) return;
+  Isolate* isolate = Isolate::UncheckedCurrent();
+  if (isolate == NULL || !isolate->IsInitialized() || !isolate->IsInUse()) {
+    // We require a fully initialized and entered isolate.
+    return;
+  }
+  if (v8::Locker::IsActive() &&
+      !isolate->thread_manager()->IsLockedByCurrentThread()) {
+    return;
+  }
+
+  Sampler* sampler = isolate->logger()->sampler();
+  if (sampler == NULL || !sampler->IsActive()) return;
+
+  TickSample sample_obj;
+  TickSample* sample = CpuProfiler::TickSampleEvent(isolate);
+  if (sample == NULL) sample = &sample_obj;
+
+  // Extracting the sample from the context is extremely machine dependent.
+  ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context);
+  mcontext_t& mcontext = ucontext->uc_mcontext;
+  sample->state = isolate->current_vm_state();
+#if V8_HOST_ARCH_IA32
+  sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_EIP]);
+  sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_ESP]);
+  sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_EBP]);
+#endif
+  sampler->SampleStack(sample);
+  sampler->Tick(sample);
+}
+
+
+class SignalSender : public Thread {
+ public:
+  enum SleepInterval {
+    HALF_INTERVAL,
+    FULL_INTERVAL
+  };
+
+  static const int kSignalSenderStackSize = 64 * KB;
+
+  explicit SignalSender(int interval)
+      : Thread(Thread::Options("SignalSender", kSignalSenderStackSize)),
+        interval_(interval) {}
+
+  static void SetUp() { if (!mutex_) mutex_ = OS::CreateMutex(); }
+  static void TearDown() { delete mutex_; }
+
+  static void AddActiveSampler(Sampler* sampler) {
+    ScopedLock lock(mutex_);
+    SamplerRegistry::AddActiveSampler(sampler);
+    if (instance_ == NULL) {
+      // Install a signal handler.
+      struct sigaction sa;
+      sa.sa_sigaction = ProfilerSignalHandler;
+      sigemptyset(&sa.sa_mask);
+      sa.sa_flags = SA_RESTART | SA_SIGINFO;
+      signal_handler_installed_ =
+          (sigaction(SIGPROF, &sa, &old_signal_handler_) == 0);
+
+      // Start a thread that sends SIGPROF signal to VM threads.
+      instance_ = new SignalSender(sampler->interval());
+      instance_->Start();
+    } else {
+      ASSERT(instance_->interval_ == sampler->interval());
+    }
+  }
+
+  static void RemoveActiveSampler(Sampler* sampler) {
+    ScopedLock lock(mutex_);
+    SamplerRegistry::RemoveActiveSampler(sampler);
+    if (SamplerRegistry::GetState() == SamplerRegistry::HAS_NO_SAMPLERS) {
+      RuntimeProfiler::StopRuntimeProfilerThreadBeforeShutdown(instance_);
+      delete instance_;
+      instance_ = NULL;
+
+      // Restore the old signal handler.
+      if (signal_handler_installed_) {
+        sigaction(SIGPROF, &old_signal_handler_, 0);
+        signal_handler_installed_ = false;
+      }
+    }
+  }
+
+  // Implement Thread::Run().
+  virtual void Run() {
+    SamplerRegistry::State state;
+    while ((state = SamplerRegistry::GetState()) !=
+           SamplerRegistry::HAS_NO_SAMPLERS) {
+      bool cpu_profiling_enabled =
+          (state == SamplerRegistry::HAS_CPU_PROFILING_SAMPLERS);
+      bool runtime_profiler_enabled = RuntimeProfiler::IsEnabled();
+      // When CPU profiling is enabled both JavaScript and C++ code is
+      // profiled. We must not suspend.
+      if (!cpu_profiling_enabled) {
+        if (rate_limiter_.SuspendIfNecessary()) continue;
+      }
+      if (cpu_profiling_enabled && runtime_profiler_enabled) {
+        if (!SamplerRegistry::IterateActiveSamplers(&DoCpuProfile, this)) {
+          return;
+        }
+        Sleep(HALF_INTERVAL);
+        if (!SamplerRegistry::IterateActiveSamplers(&DoRuntimeProfile, NULL)) {
+          return;
+        }
+        Sleep(HALF_INTERVAL);
+      } else {
+        if (cpu_profiling_enabled) {
+          if (!SamplerRegistry::IterateActiveSamplers(&DoCpuProfile,
+                                                      this)) {
+            return;
+          }
+        }
+        if (runtime_profiler_enabled) {
+          if (!SamplerRegistry::IterateActiveSamplers(&DoRuntimeProfile,
+                                                      NULL)) {
+            return;
+          }
+        }
+        Sleep(FULL_INTERVAL);
+      }
+    }
+  }
+
+  static void DoCpuProfile(Sampler* sampler, void* raw_sender) {
+    if (!sampler->IsProfiling()) return;
+    SignalSender* sender = reinterpret_cast<SignalSender*>(raw_sender);
+    sender->SendProfilingSignal(sampler->platform_data()->vm_tid());
+  }
+
+  static void DoRuntimeProfile(Sampler* sampler, void* ignored) {
+    if (!sampler->isolate()->IsInitialized()) return;
+    sampler->isolate()->runtime_profiler()->NotifyTick();
+  }
+
+  void SendProfilingSignal(pthread_t tid) {
+    if (!signal_handler_installed_) return;
+    pthread_kill(tid, SIGPROF);
+  }
+
+  void Sleep(SleepInterval full_or_half) {
+    // Convert ms to us and subtract 100 us to compensate delays
+    // occuring during signal delivery.
+    useconds_t interval = interval_ * 1000 - 100;
+    if (full_or_half == HALF_INTERVAL) interval /= 2;
+    int result = usleep(interval);
+#ifdef DEBUG
+    if (result != 0 && errno != EINTR) {
+      fprintf(stderr,
+              "SignalSender usleep error; interval = %u, errno = %d\n",
+              interval,
+              errno);
+      ASSERT(result == 0 || errno == EINTR);
+    }
+#endif
+    USE(result);
+  }
+
+  const int interval_;
+  RuntimeProfilerRateLimiter rate_limiter_;
+
+  // Protects the process wide state below.
+  static Mutex* mutex_;
+  static SignalSender* instance_;
+  static bool signal_handler_installed_;
+  static struct sigaction old_signal_handler_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(SignalSender);
+};
+
+Mutex* SignalSender::mutex_ = NULL;
+SignalSender* SignalSender::instance_ = NULL;
+struct sigaction SignalSender::old_signal_handler_;
+bool SignalSender::signal_handler_installed_ = false;
+
+
+void OS::SetUp() {
+  // Seed the random number generator.
+  // Convert the current time to a 64-bit integer first, before converting it
+  // to an unsigned. Going directly can cause an overflow and the seed to be
+  // set to all ones. The seed will be identical for different instances that
+  // call this setup code within the same millisecond.
+  uint64_t seed = static_cast<uint64_t>(TimeCurrentMillis());
+  srandom(static_cast<unsigned int>(seed));
+  limit_mutex = CreateMutex();
+  SignalSender::SetUp();
+}
+
+
+void OS::TearDown() {
+  SignalSender::TearDown();
+  delete limit_mutex;
+}
+
+
+Sampler::Sampler(Isolate* isolate, int interval)
+    : isolate_(isolate),
+      interval_(interval),
+      profiling_(false),
+      active_(false),
+      samples_taken_(0) {
+  data_ = new PlatformData;
+}
+
+
+Sampler::~Sampler() {
+  ASSERT(!IsActive());
+  delete data_;
+}
+
+
+void Sampler::Start() {
+  ASSERT(!IsActive());
+  SetActive(true);
+  SignalSender::AddActiveSampler(this);
+}
+
+
+void Sampler::Stop() {
+  ASSERT(IsActive());
+  SignalSender::RemoveActiveSampler(this);
+  SetActive(false);
+}
+
+
+} }  // namespace v8::internal
--- a/tools/gyp/v8.gyp
+++ b/tools/gyp/v8.gyp
@@ -723,6 +723,17 @@
                 '../../src/platform-posix.cc'
               ]},
             ],
+            ['OS=="hurd"', {
+                'link_settings': {
+                  'libraries': [
+                    '-lpthread',
+                ]},
+                'sources': [
+                  '../../src/platform-gnu.cc',
+                  '../../src/platform-posix.cc'
+                ],
+              }
+            ],
             ['OS=="win"', {
               'sources': [
                 '../../src/platform-win32.cc',