Exemplo n.º 1
0
/** Launch threads until we have <b>n</b>. */
static int
threadpool_start_threads(threadpool_t *pool, int n)
{
  if (n < 0)
    return -1;
  if (n > MAX_THREADS)
    n = MAX_THREADS;

  tor_mutex_acquire(&pool->lock);

  if (pool->n_threads < n)
    pool->threads = tor_reallocarray(pool->threads,
                                     sizeof(workerthread_t*), n);

  while (pool->n_threads < n) {
    void *state = pool->new_thread_state_fn(pool->new_thread_state_arg);
    workerthread_t *thr = workerthread_new(state, pool, pool->reply_queue);

    if (!thr) {
      tor_mutex_release(&pool->lock);
      return -1;
    }
    thr->index = pool->n_threads;
    pool->threads[pool->n_threads++] = thr;
  }
  tor_mutex_release(&pool->lock);

  return 0;
}
Exemplo n.º 2
0
/**
 * Process all pending replies on a reply queue. The main thread should call
 * this function every time the socket returned by replyqueue_get_socket() is
 * readable.
 */
void
replyqueue_process(replyqueue_t *queue)
{
  if (queue->alert.drain_fn(queue->alert.read_fd) < 0) {
    static ratelim_t warn_limit = RATELIM_INIT(7200);
    log_fn_ratelim(&warn_limit, LOG_WARN, LD_GENERAL,
                   "Failure from drain_fd");
  }

  tor_mutex_acquire(&queue->lock);
  while (!TOR_TAILQ_EMPTY(&queue->answers)) {
    /* lock must be held at this point.*/
    workqueue_entry_t *work = TOR_TAILQ_FIRST(&queue->answers);
    TOR_TAILQ_REMOVE(&queue->answers, work, next_work);
    tor_mutex_release(&queue->lock);
    work->on_pool = NULL;

    work->reply_fn(work->arg);
    workqueue_entry_free(work);

    tor_mutex_acquire(&queue->lock);
  }

  tor_mutex_release(&queue->lock);
}
/** Launch threads until we have <b>n</b>. */
static int
threadpool_start_threads(threadpool_t *pool, int n)
{
  if (BUG(n < 0))
    return -1; // LCOV_EXCL_LINE
  if (n > MAX_THREADS)
    n = MAX_THREADS;

  tor_mutex_acquire(&pool->lock);

  if (pool->n_threads < n)
    pool->threads = tor_reallocarray(pool->threads,
                                     sizeof(workerthread_t*), n);

  while (pool->n_threads < n) {
    void *state = pool->new_thread_state_fn(pool->new_thread_state_arg);
    workerthread_t *thr = workerthread_new(state, pool, pool->reply_queue);

    if (!thr) {
      //LCOV_EXCL_START
      tor_assert_nonfatal_unreached();
      pool->free_thread_state_fn(state);
      tor_mutex_release(&pool->lock);
      return -1;
      //LCOV_EXCL_STOP
    }
    thr->index = pool->n_threads;
    pool->threads[pool->n_threads++] = thr;
  }
  tor_mutex_release(&pool->lock);

  return 0;
}
Exemplo n.º 4
0
static void
cv_test_thr_fn_(void *arg)
{
  cv_testinfo_t *i = arg;
  int tid, r;

  tor_mutex_acquire(i->mutex);
  tid = i->n_threads++;
  tor_mutex_release(i->mutex);
  (void) tid;

  tor_mutex_acquire(i->mutex);
  while (1) {
    if (i->addend) {
      i->value += i->addend;
      i->addend = 0;
    }

    if (i->shutdown) {
      ++i->n_shutdown;
      i->shutdown = 0;
      tor_mutex_release(i->mutex);
      spawn_exit();
    }
    r = tor_cond_wait(i->cond, i->mutex, i->tv);
    ++i->n_wakeups;
    if (r == 1) {
      ++i->n_timeouts;
      tor_mutex_release(i->mutex);
      spawn_exit();
    }
  }
}
/**
 * Main function for the worker thread.
 */
static void
worker_thread_main(void *thread_)
{
  workerthread_t *thread = thread_;
  threadpool_t *pool = thread->in_pool;
  workqueue_entry_t *work;
  workqueue_reply_t result;

  tor_mutex_acquire(&pool->lock);
  while (1) {
    /* lock must be held at this point. */
    while (worker_thread_has_work(thread)) {
      /* lock must be held at this point. */
      if (thread->in_pool->generation != thread->generation) {
        void *arg = thread->in_pool->update_args[thread->index];
        thread->in_pool->update_args[thread->index] = NULL;
        workqueue_reply_t (*update_fn)(void*,void*) =
            thread->in_pool->update_fn;
        thread->generation = thread->in_pool->generation;
        tor_mutex_release(&pool->lock);

        workqueue_reply_t r = update_fn(thread->state, arg);

        if (r != WQ_RPL_REPLY) {
          return;
        }

        tor_mutex_acquire(&pool->lock);
        continue;
      }
      work = TOR_TAILQ_FIRST(&pool->work);
      TOR_TAILQ_REMOVE(&pool->work, work, next_work);
      work->pending = 0;
      tor_mutex_release(&pool->lock);

      /* We run the work function without holding the thread lock. This
       * is the main thread's first opportunity to give us more work. */
      result = work->fn(thread->state, work->arg);

      /* Queue the reply for the main thread. */
      queue_reply(thread->reply_queue, work);

      /* We may need to exit the thread. */
      if (result != WQ_RPL_REPLY) {
        return;
      }
      tor_mutex_acquire(&pool->lock);
    }
    /* At this point the lock is held, and there is no work in this thread's
     * queue. */

    /* TODO: support an idle-function */

    /* Okay. Now, wait till somebody has work for us. */
    if (tor_cond_wait(&pool->condition, &pool->lock, NULL) < 0) {
      log_warn(LD_GENERAL, "Fail tor_cond_wait.");
    }
  }
}
Exemplo n.º 6
0
static void
test_threads_conditionvar(void *arg)
{
  cv_testinfo_t *ti=NULL;
  const struct timeval msec100 = { 0, 100*1000 };
  const int timeout = !strcmp(arg, "tv");

  ti = cv_testinfo_new();
  if (timeout) {
    ti->tv = &msec100;
  }
  spawn_func(cv_test_thr_fn_, ti);
  spawn_func(cv_test_thr_fn_, ti);
  spawn_func(cv_test_thr_fn_, ti);
  spawn_func(cv_test_thr_fn_, ti);

  tor_mutex_acquire(ti->mutex);
  ti->addend = 7;
  ti->shutdown = 1;
  tor_cond_signal_one(ti->cond);
  tor_mutex_release(ti->mutex);

#define SPIN()                                  \
  while (1) {                                   \
    tor_mutex_acquire(ti->mutex);               \
    if (ti->addend == 0) {                      \
      break;                                    \
    }                                           \
    tor_mutex_release(ti->mutex);               \
  }

  SPIN();

  ti->addend = 30;
  ti->shutdown = 1;
  tor_cond_signal_all(ti->cond);
  tor_mutex_release(ti->mutex);
  SPIN();

  ti->addend = 1000;
  if (! timeout) ti->shutdown = 1;
  tor_cond_signal_one(ti->cond);
  tor_mutex_release(ti->mutex);
  SPIN();
  ti->addend = 300;
  if (! timeout) ti->shutdown = 1;
  tor_cond_signal_all(ti->cond);
  tor_mutex_release(ti->mutex);

  SPIN();
  tor_mutex_release(ti->mutex);

  tt_int_op(ti->value, ==, 1337);
  if (!timeout) {
    tt_int_op(ti->n_shutdown, ==, 4);
  } else {
Exemplo n.º 7
0
/** Log a message <b>msg</b> at <b>severity</b> in <b>domain</b>, and follow
 * that with a backtrace log. */
void
log_backtrace(int severity, int domain, const char *msg)
{
  int depth;
  char **symbols;
  int i;

  tor_mutex_acquire(&cb_buf_mutex);

  depth = backtrace(cb_buf, MAX_DEPTH);
  symbols = backtrace_symbols(cb_buf, depth);

  tor_log(severity, domain, "%s. Stack trace:", msg);
  if (!symbols) {
    tor_log(severity, domain, "    Unable to generate backtrace.");
    goto done;
  }
  for (i=0; i < depth; ++i) {
    tor_log(severity, domain, "    %s", symbols[i]);
  }
  free(symbols);

 done:
  tor_mutex_release(&cb_buf_mutex);
}
Exemplo n.º 8
0
/** Log a message <b>msg</b> at <b>severity</b> in <b>domain</b>, and follow
 * that with a backtrace log. */
void
log_backtrace(int severity, int domain, const char *msg)
{
  size_t depth;
  char **symbols;
  size_t i;

  tor_mutex_acquire(&cb_buf_mutex);

  depth = backtrace(cb_buf, MAX_DEPTH);
  symbols = backtrace_symbols(cb_buf, (int)depth);

  tor_log(severity, domain, "%s. Stack trace:", msg);
  if (!symbols) {
    /* LCOV_EXCL_START -- we can't provoke this. */
    tor_log(severity, domain, "    Unable to generate backtrace.");
    goto done;
    /* LCOV_EXCL_STOP */
  }
  for (i=0; i < depth; ++i) {
    tor_log(severity, domain, "    %s", symbols[i]);
  }
  raw_free(symbols);

 done:
  tor_mutex_release(&cb_buf_mutex);
}
Exemplo n.º 9
0
static void
replysock_readable_cb(tor_socket_t sock, short what, void *arg)
{
  threadpool_t *tp = arg;
  replyqueue_t *rq = threadpool_get_replyqueue(tp);

  int old_r = n_received;
  (void) sock;
  (void) what;

  replyqueue_process(rq);
  if (old_r == n_received)
    return;

  if (opt_verbose) {
    printf("%d / %d", n_received, n_sent);
    if (opt_n_cancel)
      printf(" (%d cancelled, %d uncancellable)",
             n_successful_cancel, n_failed_cancel);
    puts("");
  }
#ifdef TRACK_RESPONSES
  tor_mutex_acquire(&bitmap_mutex);
  for (i = 0; i < opt_n_items; ++i) {
    if (bitarray_is_set(received, i))
      putc('o', stdout);
    else if (bitarray_is_set(handled, i))
      putc('!', stdout);
    else
      putc('.', stdout);
  }
  puts("");
  tor_mutex_release(&bitmap_mutex);
#endif

  if (n_sent - (n_received+n_successful_cancel) < opt_n_lowwater) {
    int n_to_send = n_received + opt_n_inflight - n_sent;
    if (n_to_send > opt_n_items - n_sent)
      n_to_send = opt_n_items - n_sent;
    add_n_work_items(tp, n_to_send);
  }

  if (shutting_down == 0 &&
      n_received+n_successful_cancel == n_sent &&
      n_sent >= opt_n_items) {
    shutting_down = 1;
    threadpool_queue_update(tp, NULL,
                             workqueue_do_shutdown, NULL, NULL);
    // Anything we add after starting the shutdown must not be executed.
    threadpool_queue_work(tp, workqueue_shutdown_error,
                          handle_reply_shutdown, NULL);
    {
      struct timeval limit = { 2, 0 };
      tor_event_base_loopexit(tor_libevent_get_base(), &limit);
    }
  }
}
Exemplo n.º 10
0
/** Helper function for threading unit tests: This function runs in a
 * subthread. It grabs its own mutex (start1 or start2) to make sure that it
 * should start, then it repeatedly alters _test_thread_strmap protected by
 * thread_test_mutex_. */
static void
thread_test_func_(void* _s)
{
  char *s = _s;
  int i, *count;
  tor_mutex_t *m;
  char buf[64];
  char **cp;
  if (!strcmp(s, "thread 1")) {
    m = thread_test_start1_;
    cp = &thread1_name_;
    count = &t1_count;
    thread_fn_tid1 = tor_get_thread_id();
  } else {
    m = thread_test_start2_;
    cp = &thread2_name_;
    count = &t2_count;
    thread_fn_tid2 = tor_get_thread_id();
  }

  tor_snprintf(buf, sizeof(buf), "%lu", tor_get_thread_id());
  *cp = tor_strdup(buf);

  tor_mutex_acquire(m);

  for (i=0; i<10000; ++i) {
    tor_mutex_acquire(thread_test_mutex_);
    strmap_set(thread_test_strmap_, "last to run", *cp);
    ++*count;
    tor_mutex_release(thread_test_mutex_);
  }
  tor_mutex_acquire(thread_test_mutex_);
  strmap_set(thread_test_strmap_, s, *cp);
  if (in_main_thread())
    ++thread_fns_failed;
  tor_mutex_release(thread_test_mutex_);

  tor_mutex_release(m);

  spawn_exit();
}
Exemplo n.º 11
0
static void
mark_handled(int serial)
{
#ifdef TRACK_RESPONSES
  tor_mutex_acquire(&bitmap_mutex);
  tor_assert(serial < handled_len);
  tor_assert(! bitarray_is_set(handled, serial));
  bitarray_set(handled, serial);
  tor_mutex_release(&bitmap_mutex);
#else
  (void)serial;
#endif
}
Exemplo n.º 12
0
/** Put a reply on the reply queue.  The reply must not currently be on
 * any thread's work queue. */
static void
queue_reply(replyqueue_t *queue, workqueue_entry_t *work)
{
  int was_empty;
  tor_mutex_acquire(&queue->lock);
  was_empty = TOR_TAILQ_EMPTY(&queue->answers);
  TOR_TAILQ_INSERT_TAIL(&queue->answers, work, next_work);
  tor_mutex_release(&queue->lock);

  if (was_empty) {
    if (queue->alert.alert_fn(queue->alert.write_fd) < 0) {
      /* XXXX complain! */
    }
  }
}
Exemplo n.º 13
0
/**
 * Cancel a workqueue_entry_t that has been returned from
 * threadpool_queue_work.
 *
 * You must not call this function on any work whose reply function has been
 * executed in the main thread; that will cause undefined behavior (probably,
 * a crash).
 *
 * If the work is cancelled, this function return the argument passed to the
 * work function. It is the caller's responsibility to free this storage.
 *
 * This function will have no effect if the worker thread has already executed
 * or begun to execute the work item.  In that case, it will return NULL.
 */
void *
workqueue_entry_cancel(workqueue_entry_t *ent)
{
  int cancelled = 0;
  void *result = NULL;
  tor_mutex_acquire(&ent->on_pool->lock);
  if (ent->pending) {
    TOR_TAILQ_REMOVE(&ent->on_pool->work, ent, next_work);
    cancelled = 1;
    result = ent->arg;
  }
  tor_mutex_release(&ent->on_pool->lock);

  if (cancelled) {
    workqueue_entry_free(ent);
  }
  return result;
}
Exemplo n.º 14
0
/**
 * Queue a copy of a work item for every thread in a pool.  This can be used,
 * for example, to tell the threads to update some parameter in their states.
 *
 * Arguments are as for <b>threadpool_queue_work</b>, except that the
 * <b>arg</b> value is passed to <b>dup_fn</b> once per each thread to
 * make a copy of it.
 *
 * UPDATE FUNCTIONS MUST BE IDEMPOTENT.  We do not guarantee that every update
 * will be run.  If a new update is scheduled before the old update finishes
 * running, then the new will replace the old in any threads that haven't run
 * it yet.
 *
 * Return 0 on success, -1 on failure.
 */
int
threadpool_queue_update(threadpool_t *pool,
                         void *(*dup_fn)(void *),
                         int (*fn)(void *, void *),
                         void (*free_fn)(void *),
                         void *arg)
{
  int i, n_threads;
  void (*old_args_free_fn)(void *arg);
  void **old_args;
  void **new_args;

  tor_mutex_acquire(&pool->lock);
  n_threads = pool->n_threads;
  old_args = pool->update_args;
  old_args_free_fn = pool->free_update_arg_fn;

  new_args = tor_calloc(n_threads, sizeof(void*));
  for (i = 0; i < n_threads; ++i) {
    if (dup_fn)
      new_args[i] = dup_fn(arg);
    else
      new_args[i] = arg;
  }

  pool->update_args = new_args;
  pool->free_update_arg_fn = free_fn;
  pool->update_fn = fn;
  ++pool->generation;

  tor_mutex_release(&pool->lock);

  tor_cond_signal_all(&pool->condition);

  if (old_args) {
    for (i = 0; i < n_threads; ++i) {
      if (old_args[i] && old_args_free_fn)
        old_args_free_fn(old_args[i]);
    }
    tor_free(old_args);
  }

  return 0;
}
Exemplo n.º 15
0
/**
 * Queue an item of work for a thread in a thread pool.  The function
 * <b>fn</b> will be run in a worker thread, and will receive as arguments the
 * thread's state object, and the provided object <b>arg</b>. It must return
 * one of WQ_RPL_REPLY, WQ_RPL_ERROR, or WQ_RPL_SHUTDOWN.
 *
 * Regardless of its return value, the function <b>reply_fn</b> will later be
 * run in the main thread when it invokes replyqueue_process(), and will
 * receive as its argument the same <b>arg</b> object.  It's the reply
 * function's responsibility to free the work object.
 *
 * On success, return a workqueue_entry_t object that can be passed to
 * workqueue_entry_cancel(). On failure, return NULL.
 *
 * Note that because each thread has its own work queue, work items may not
 * be executed strictly in order.
 */
workqueue_entry_t *
threadpool_queue_work(threadpool_t *pool,
                      int (*fn)(void *, void *),
                      void (*reply_fn)(void *),
                      void *arg)
{
  workqueue_entry_t *ent = workqueue_entry_new(fn, reply_fn, arg);
  ent->on_pool = pool;
  ent->pending = 1;

  tor_mutex_acquire(&pool->lock);

  TOR_TAILQ_INSERT_TAIL(&pool->work, ent, next_work);

  tor_mutex_release(&pool->lock);

  tor_cond_signal_one(&pool->condition);

  return ent;
}
Exemplo n.º 16
0
/** Run unit tests for threading logic. */
static void
test_threads_basic(void *arg)
{
  char *s1 = NULL, *s2 = NULL;
  int done = 0, timedout = 0;
  time_t started;
#ifndef _WIN32
  struct timeval tv;
  tv.tv_sec=0;
  tv.tv_usec=100*1000;
#endif
  (void) arg;

  set_main_thread();

  thread_test_mutex_ = tor_mutex_new();
  thread_test_start1_ = tor_mutex_new();
  thread_test_start2_ = tor_mutex_new();
  thread_test_strmap_ = strmap_new();
  s1 = tor_strdup("thread 1");
  s2 = tor_strdup("thread 2");
  tor_mutex_acquire(thread_test_start1_);
  tor_mutex_acquire(thread_test_start2_);
  spawn_func(thread_test_func_, s1);
  spawn_func(thread_test_func_, s2);
  tor_mutex_release(thread_test_start2_);
  tor_mutex_release(thread_test_start1_);
  started = time(NULL);
  while (!done) {
    tor_mutex_acquire(thread_test_mutex_);
    strmap_assert_ok(thread_test_strmap_);
    if (strmap_get(thread_test_strmap_, "thread 1") &&
        strmap_get(thread_test_strmap_, "thread 2")) {
      done = 1;
    } else if (time(NULL) > started + 150) {
      timedout = done = 1;
    }
    tor_mutex_release(thread_test_mutex_);
#ifndef _WIN32
    /* Prevent the main thread from starving the worker threads. */
    select(0, NULL, NULL, NULL, &tv);
#endif
  }
  tor_mutex_acquire(thread_test_start1_);
  tor_mutex_release(thread_test_start1_);
  tor_mutex_acquire(thread_test_start2_);
  tor_mutex_release(thread_test_start2_);

  tor_mutex_free(thread_test_mutex_);

  if (timedout) {
    printf("\nTimed out: %d %d", t1_count, t2_count);
    tt_assert(strmap_get(thread_test_strmap_, "thread 1"));
    tt_assert(strmap_get(thread_test_strmap_, "thread 2"));
    tt_assert(!timedout);
  }

  /* different thread IDs. */
  tt_assert(strcmp(strmap_get(thread_test_strmap_, "thread 1"),
                     strmap_get(thread_test_strmap_, "thread 2")));
  tt_assert(!strcmp(strmap_get(thread_test_strmap_, "thread 1"),
                      strmap_get(thread_test_strmap_, "last to run")) ||
              !strcmp(strmap_get(thread_test_strmap_, "thread 2"),
                      strmap_get(thread_test_strmap_, "last to run")));

  tt_int_op(thread_fns_failed, ==, 0);
  tt_int_op(thread_fn_tid1, !=, thread_fn_tid2);

 done:
  tor_free(s1);
  tor_free(s2);
  tor_free(thread1_name_);
  tor_free(thread2_name_);
  if (thread_test_strmap_)
    strmap_free(thread_test_strmap_, NULL);
  if (thread_test_start1_)
    tor_mutex_free(thread_test_start1_);
  if (thread_test_start2_)
    tor_mutex_free(thread_test_start2_);
}