Пример #1
0
// Starts the deadline timer.
static void start_timer_if_needed(grpc_exec_ctx* exec_ctx,
                                  grpc_call_element* elem,
                                  gpr_timespec deadline) {
  grpc_deadline_state* deadline_state = elem->call_data;
  deadline = gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC);
  if (gpr_time_cmp(deadline, gpr_inf_future(GPR_CLOCK_MONOTONIC)) != 0) {
    // Take a reference to the call stack, to be owned by the timer.
    GRPC_CALL_STACK_REF(deadline_state->call_stack, "deadline_timer");
    gpr_mu_lock(&deadline_state->timer_mu);
    deadline_state->timer_pending = true;
    grpc_timer_init(exec_ctx, &deadline_state->timer, deadline, timer_callback,
                    elem, gpr_now(GPR_CLOCK_MONOTONIC));
    gpr_mu_unlock(&deadline_state->timer_mu);
  }
}
Пример #2
0
/* Constructor for call_data */
static grpc_error *cc_init_call_elem(grpc_exec_ctx *exec_ctx,
                                     grpc_call_element *elem,
                                     grpc_call_element_args *args) {
  channel_data *chand = elem->channel_data;
  call_data *calld = elem->call_data;
  // Initialize data members.
  grpc_deadline_state_init(exec_ctx, elem, args->call_stack);
  calld->path = GRPC_MDSTR_REF(args->path);
  calld->call_start_time = args->start_time;
  calld->deadline = gpr_convert_clock_type(args->deadline, GPR_CLOCK_MONOTONIC);
  calld->wait_for_ready_from_service_config = WAIT_FOR_READY_UNSET;
  calld->cancel_error = GRPC_ERROR_NONE;
  gpr_atm_rel_store(&calld->subchannel_call, 0);
  gpr_mu_init(&calld->mu);
  calld->connected_subchannel = NULL;
  calld->waiting_ops = NULL;
  calld->waiting_ops_count = 0;
  calld->waiting_ops_capacity = 0;
  calld->creation_phase = GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING;
  calld->owning_call = args->call_stack;
  calld->pollent = NULL;
  // If the resolver has already returned results, then we can access
  // the service config parameters immediately.  Otherwise, we need to
  // defer that work until the resolver returns an initial result.
  // TODO(roth): This code is almost but not quite identical to the code
  // in read_service_config() above.  It would be nice to find a way to
  // combine them, to avoid having to maintain it twice.
  gpr_mu_lock(&chand->mu);
  if (chand->lb_policy != NULL) {
    // We already have a resolver result, so check for service config.
    if (chand->method_params_table != NULL) {
      grpc_mdstr_hash_table *method_params_table =
          grpc_mdstr_hash_table_ref(chand->method_params_table);
      gpr_mu_unlock(&chand->mu);
      method_parameters *method_params =
          grpc_method_config_table_get(method_params_table, args->path);
      if (method_params != NULL) {
        if (gpr_time_cmp(method_params->timeout,
                         gpr_time_0(GPR_CLOCK_MONOTONIC)) != 0) {
          gpr_timespec per_method_deadline =
              gpr_time_add(calld->call_start_time, method_params->timeout);
          calld->deadline = gpr_time_min(calld->deadline, per_method_deadline);
        }
        if (method_params->wait_for_ready != WAIT_FOR_READY_UNSET) {
          calld->wait_for_ready_from_service_config =
              method_params->wait_for_ready;
        }
      }
      grpc_mdstr_hash_table_unref(method_params_table);
    } else {
      gpr_mu_unlock(&chand->mu);
    }
  } else {
    // We don't yet have a resolver result, so register a callback to
    // get the service config data once the resolver returns.
    // Take a reference to the call stack to be owned by the callback.
    GRPC_CALL_STACK_REF(calld->owning_call, "read_service_config");
    grpc_closure_init(&calld->read_service_config, read_service_config, elem);
    grpc_closure_list_append(&chand->waiting_for_config_closures,
                             &calld->read_service_config, GRPC_ERROR_NONE);
    gpr_mu_unlock(&chand->mu);
  }
  // Start the deadline timer with the current deadline value.  If we
  // do not yet have service config data, then the timer may be reset
  // later.
  grpc_deadline_state_start(exec_ctx, elem, calld->deadline);
  return GRPC_ERROR_NONE;
}
Пример #3
0
// The logic here is fairly complicated, due to (a) the fact that we
// need to handle the case where we receive the send op before the
// initial metadata op, and (b) the need for efficiency, especially in
// the streaming case.
// TODO(ctiller): Explain this more thoroughly.
static void cc_start_transport_stream_op(grpc_exec_ctx *exec_ctx,
                                         grpc_call_element *elem,
                                         grpc_transport_stream_op *op) {
  call_data *calld = elem->call_data;
  channel_data *chand = elem->channel_data;
  GRPC_CALL_LOG_OP(GPR_INFO, elem, op);
  grpc_deadline_state_client_start_transport_stream_op(exec_ctx, elem, op);
  /* try to (atomically) get the call */
  grpc_subchannel_call *call = GET_CALL(calld);
  GPR_TIMER_BEGIN("cc_start_transport_stream_op", 0);
  if (call == CANCELLED_CALL) {
    grpc_transport_stream_op_finish_with_failure(
        exec_ctx, op, GRPC_ERROR_REF(calld->cancel_error));
    GPR_TIMER_END("cc_start_transport_stream_op", 0);
    return;
  }
  if (call != NULL) {
    grpc_subchannel_call_process_op(exec_ctx, call, op);
    GPR_TIMER_END("cc_start_transport_stream_op", 0);
    return;
  }
  /* we failed; lock and figure out what to do */
  gpr_mu_lock(&calld->mu);
retry:
  /* need to recheck that another thread hasn't set the call */
  call = GET_CALL(calld);
  if (call == CANCELLED_CALL) {
    gpr_mu_unlock(&calld->mu);
    grpc_transport_stream_op_finish_with_failure(
        exec_ctx, op, GRPC_ERROR_REF(calld->cancel_error));
    GPR_TIMER_END("cc_start_transport_stream_op", 0);
    return;
  }
  if (call != NULL) {
    gpr_mu_unlock(&calld->mu);
    grpc_subchannel_call_process_op(exec_ctx, call, op);
    GPR_TIMER_END("cc_start_transport_stream_op", 0);
    return;
  }
  /* if this is a cancellation, then we can raise our cancelled flag */
  if (op->cancel_error != GRPC_ERROR_NONE) {
    if (!gpr_atm_rel_cas(&calld->subchannel_call, 0,
                         (gpr_atm)(uintptr_t)CANCELLED_CALL)) {
      goto retry;
    } else {
      // Stash a copy of cancel_error in our call data, so that we can use
      // it for subsequent operations.  This ensures that if the call is
      // cancelled before any ops are passed down (e.g., if the deadline
      // is in the past when the call starts), we can return the right
      // error to the caller when the first op does get passed down.
      calld->cancel_error = GRPC_ERROR_REF(op->cancel_error);
      switch (calld->creation_phase) {
        case GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING:
          fail_locked(exec_ctx, calld, GRPC_ERROR_REF(op->cancel_error));
          break;
        case GRPC_SUBCHANNEL_CALL_HOLDER_PICKING_SUBCHANNEL:
          pick_subchannel(exec_ctx, elem, NULL, 0, &calld->connected_subchannel,
                          NULL, GRPC_ERROR_REF(op->cancel_error));
          break;
      }
      gpr_mu_unlock(&calld->mu);
      grpc_transport_stream_op_finish_with_failure(
          exec_ctx, op, GRPC_ERROR_REF(op->cancel_error));
      GPR_TIMER_END("cc_start_transport_stream_op", 0);
      return;
    }
  }
  /* if we don't have a subchannel, try to get one */
  if (calld->creation_phase == GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING &&
      calld->connected_subchannel == NULL &&
      op->send_initial_metadata != NULL) {
    calld->creation_phase = GRPC_SUBCHANNEL_CALL_HOLDER_PICKING_SUBCHANNEL;
    grpc_closure_init(&calld->next_step, subchannel_ready, elem);
    GRPC_CALL_STACK_REF(calld->owning_call, "pick_subchannel");
    /* If a subchannel is not available immediately, the polling entity from
       call_data should be provided to channel_data's interested_parties, so
       that IO of the lb_policy and resolver could be done under it. */
    if (pick_subchannel(exec_ctx, elem, op->send_initial_metadata,
                        op->send_initial_metadata_flags,
                        &calld->connected_subchannel, &calld->next_step,
                        GRPC_ERROR_NONE)) {
      calld->creation_phase = GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING;
      GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call, "pick_subchannel");
    } else {
      grpc_polling_entity_add_to_pollset_set(exec_ctx, calld->pollent,
                                             chand->interested_parties);
    }
  }
  /* if we've got a subchannel, then let's ask it to create a call */
  if (calld->creation_phase == GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING &&
      calld->connected_subchannel != NULL) {
    grpc_subchannel_call *subchannel_call = NULL;
    grpc_error *error = grpc_connected_subchannel_create_call(
        exec_ctx, calld->connected_subchannel, calld->pollent, calld->path,
        calld->deadline, &subchannel_call);
    if (error != GRPC_ERROR_NONE) {
      subchannel_call = CANCELLED_CALL;
      fail_locked(exec_ctx, calld, GRPC_ERROR_REF(error));
      grpc_transport_stream_op_finish_with_failure(exec_ctx, op, error);
    }
    gpr_atm_rel_store(&calld->subchannel_call,
                      (gpr_atm)(uintptr_t)subchannel_call);
    retry_waiting_locked(exec_ctx, calld);
    goto retry;
  }
  /* nothing to be done but wait */
  add_waiting_locked(calld, op);
  gpr_mu_unlock(&calld->mu);
  GPR_TIMER_END("cc_start_transport_stream_op", 0);
}
Пример #4
0
// The logic here is fairly complicated, due to (a) the fact that we
// need to handle the case where we receive the send op before the
// initial metadata op, and (b) the need for efficiency, especially in
// the streaming case.
// TODO(ctiller): Explain this more thoroughly.
static void cc_start_transport_stream_op(grpc_exec_ctx *exec_ctx,
                                         grpc_call_element *elem,
                                         grpc_transport_stream_op *op) {
  call_data *calld = elem->call_data;
  GRPC_CALL_LOG_OP(GPR_INFO, elem, op);
  /* try to (atomically) get the call */
  grpc_subchannel_call *call = GET_CALL(calld);
  GPR_TIMER_BEGIN("cc_start_transport_stream_op", 0);
  if (call == CANCELLED_CALL) {
    grpc_transport_stream_op_finish_with_failure(exec_ctx, op,
                                                 GRPC_ERROR_CANCELLED);
    GPR_TIMER_END("cc_start_transport_stream_op", 0);
    return;
  }
  if (call != NULL) {
    grpc_subchannel_call_process_op(exec_ctx, call, op);
    GPR_TIMER_END("cc_start_transport_stream_op", 0);
    return;
  }
  /* we failed; lock and figure out what to do */
  gpr_mu_lock(&calld->mu);
retry:
  /* need to recheck that another thread hasn't set the call */
  call = GET_CALL(calld);
  if (call == CANCELLED_CALL) {
    gpr_mu_unlock(&calld->mu);
    grpc_transport_stream_op_finish_with_failure(exec_ctx, op,
                                                 GRPC_ERROR_CANCELLED);
    GPR_TIMER_END("cc_start_transport_stream_op", 0);
    return;
  }
  if (call != NULL) {
    gpr_mu_unlock(&calld->mu);
    grpc_subchannel_call_process_op(exec_ctx, call, op);
    GPR_TIMER_END("cc_start_transport_stream_op", 0);
    return;
  }
  /* if this is a cancellation, then we can raise our cancelled flag */
  if (op->cancel_error != GRPC_ERROR_NONE) {
    if (!gpr_atm_rel_cas(&calld->subchannel_call, 0,
                         (gpr_atm)(uintptr_t)CANCELLED_CALL)) {
      goto retry;
    } else {
      switch (calld->creation_phase) {
        case GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING:
          fail_locked(exec_ctx, calld, GRPC_ERROR_REF(op->cancel_error));
          break;
        case GRPC_SUBCHANNEL_CALL_HOLDER_PICKING_SUBCHANNEL:
          pick_subchannel(exec_ctx, elem, NULL, 0, &calld->connected_subchannel,
                          NULL);
          break;
      }
      gpr_mu_unlock(&calld->mu);
      grpc_transport_stream_op_finish_with_failure(exec_ctx, op,
                                                   GRPC_ERROR_CANCELLED);
      GPR_TIMER_END("cc_start_transport_stream_op", 0);
      return;
    }
  }
  /* if we don't have a subchannel, try to get one */
  if (calld->creation_phase == GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING &&
      calld->connected_subchannel == NULL &&
      op->send_initial_metadata != NULL) {
    calld->creation_phase = GRPC_SUBCHANNEL_CALL_HOLDER_PICKING_SUBCHANNEL;
    grpc_closure_init(&calld->next_step, subchannel_ready, calld);
    GRPC_CALL_STACK_REF(calld->owning_call, "pick_subchannel");
    if (pick_subchannel(exec_ctx, elem, op->send_initial_metadata,
                        op->send_initial_metadata_flags,
                        &calld->connected_subchannel, &calld->next_step)) {
      calld->creation_phase = GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING;
      GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call, "pick_subchannel");
    }
  }
  /* if we've got a subchannel, then let's ask it to create a call */
  if (calld->creation_phase == GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING &&
      calld->connected_subchannel != NULL) {
    grpc_subchannel_call *subchannel_call = NULL;
    grpc_error *error = grpc_connected_subchannel_create_call(
        exec_ctx, calld->connected_subchannel, calld->pollent,
        &subchannel_call);
    if (error != GRPC_ERROR_NONE) {
      subchannel_call = CANCELLED_CALL;
      fail_locked(exec_ctx, calld, GRPC_ERROR_REF(error));
      grpc_transport_stream_op_finish_with_failure(exec_ctx, op, error);
    }
    gpr_atm_rel_store(&calld->subchannel_call,
                      (gpr_atm)(uintptr_t)subchannel_call);
    retry_waiting_locked(exec_ctx, calld);
    goto retry;
  }
  /* nothing to be done but wait */
  add_waiting_locked(calld, op);
  gpr_mu_unlock(&calld->mu);
  GPR_TIMER_END("cc_start_transport_stream_op", 0);
}
Пример #5
0
void grpc_subchannel_call_holder_perform_op(grpc_exec_ctx *exec_ctx,
                                            grpc_subchannel_call_holder *holder,
                                            grpc_transport_stream_op *op) {
  /* try to (atomically) get the call */
  grpc_subchannel_call *call = GET_CALL(holder);
  GPR_TIMER_BEGIN("grpc_subchannel_call_holder_perform_op", 0);
  if (call == CANCELLED_CALL) {
    grpc_transport_stream_op_finish_with_failure(exec_ctx, op);
    GPR_TIMER_END("grpc_subchannel_call_holder_perform_op", 0);
    return;
  }
  if (call != NULL) {
    grpc_subchannel_call_process_op(exec_ctx, call, op);
    GPR_TIMER_END("grpc_subchannel_call_holder_perform_op", 0);
    return;
  }
  /* we failed; lock and figure out what to do */
  gpr_mu_lock(&holder->mu);
retry:
  /* need to recheck that another thread hasn't set the call */
  call = GET_CALL(holder);
  if (call == CANCELLED_CALL) {
    gpr_mu_unlock(&holder->mu);
    grpc_transport_stream_op_finish_with_failure(exec_ctx, op);
    GPR_TIMER_END("grpc_subchannel_call_holder_perform_op", 0);
    return;
  }
  if (call != NULL) {
    gpr_mu_unlock(&holder->mu);
    grpc_subchannel_call_process_op(exec_ctx, call, op);
    GPR_TIMER_END("grpc_subchannel_call_holder_perform_op", 0);
    return;
  }
  /* if this is a cancellation, then we can raise our cancelled flag */
  if (op->cancel_with_status != GRPC_STATUS_OK) {
    if (!gpr_atm_rel_cas(&holder->subchannel_call, 0, 1)) {
      goto retry;
    } else {
      switch (holder->creation_phase) {
        case GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING:
          fail_locked(exec_ctx, holder);
          break;
        case GRPC_SUBCHANNEL_CALL_HOLDER_PICKING_SUBCHANNEL:
          holder->pick_subchannel(exec_ctx, holder->pick_subchannel_arg, NULL,
                                  &holder->connected_subchannel, NULL);
          break;
      }
      gpr_mu_unlock(&holder->mu);
      grpc_transport_stream_op_finish_with_failure(exec_ctx, op);
      GPR_TIMER_END("grpc_subchannel_call_holder_perform_op", 0);
      return;
    }
  }
  /* if we don't have a subchannel, try to get one */
  if (holder->creation_phase == GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING &&
      holder->connected_subchannel == NULL &&
      op->send_initial_metadata != NULL) {
    holder->creation_phase = GRPC_SUBCHANNEL_CALL_HOLDER_PICKING_SUBCHANNEL;
    grpc_closure_init(&holder->next_step, subchannel_ready, holder);
    GRPC_CALL_STACK_REF(holder->owning_call, "pick_subchannel");
    if (holder->pick_subchannel(
            exec_ctx, holder->pick_subchannel_arg, op->send_initial_metadata,
            &holder->connected_subchannel, &holder->next_step)) {
      holder->creation_phase = GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING;
      GRPC_CALL_STACK_UNREF(exec_ctx, holder->owning_call, "pick_subchannel");
    }
  }
  /* if we've got a subchannel, then let's ask it to create a call */
  if (holder->creation_phase == GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING &&
      holder->connected_subchannel != NULL) {
    gpr_atm_rel_store(
        &holder->subchannel_call,
        (gpr_atm)(uintptr_t)grpc_connected_subchannel_create_call(
            exec_ctx, holder->connected_subchannel, holder->pollset));
    retry_waiting_locked(exec_ctx, holder);
    goto retry;
  }
  /* nothing to be done but wait */
  add_waiting_locked(holder, op);
  gpr_mu_unlock(&holder->mu);
  GPR_TIMER_END("grpc_subchannel_call_holder_perform_op", 0);
}