lock issue

[CkTD]

braft/src/braft/replicator.cpp

Lines 712 to 751 in e32b78a

	int Replicator::_continue_sending(void* arg, int error_code) {
	Replicator* r = NULL;
	bthread_id_t id = { (uint64_t)arg };
	if (bthread_id_lock(id, (void**)&r) != 0) {
	return -1;
	}
	if (error_code == ETIMEDOUT) {
	// Replication is in progress when block timeout, no need to start again
	// this case can happen when
	// 1. pipeline is enabled and
	// 2. disable readonly mode triggers another replication
	if (r->_wait_id != 0) {
	return 0;
	}
	// Send empty entries after block timeout to check the correct
	// _next_index otherwise the replictor is likely waits in
	// _wait_more_entries and no further logs would be replicated even if the
	// last_index of this followers is less than |next_index - 1|
	r->_send_empty_entries(false);
	} else if (error_code != ESTOP && !r->_is_waiter_canceled) {
	// id is unlock in _send_entries
	r->_wait_id = 0;
	r->_send_entries();
	} else if (r->_is_waiter_canceled) {
	// The replicator is checking current next index by sending empty entries or
	// install snapshot now. Although the registered waiter will be canceled
	// before the operations, there is still a little chance that LogManger already
	// waked up the waiter, and _continue_sending is waiting to execute.
	BRAFT_VLOG << "Group " << r->_options.group_id
	<< " Replicator=" << id << " canceled waiter";
	bthread_id_unlock(id);
	} else {
	LOG(WARNING) << "Group " << r->_options.group_id
	<< " Replicator=" << id << " stops sending entries";
	bthread_id_unlock(id);
	}
	return 0;
	}

block timer 中，723行 这个分枝返回之前没有 unlock id，如果走到了似乎会把 replicator 卡死？