Re: [PATCH] staging: unisys: use common return path

[Ben Romer <benjamin.romer@unisys.com>]

On 12/01/2015 03:00 AM, Dan Carpenter wrote:
> Doing One Err style error handling is often a mistake but it's ok here.

Why is it okay here? I don't understand why this function would be any 
different than the other places where the code used a goto.

If we *have* to change it I would prefer that we not add a goto and 
instead add an additional boolean local variable to control serverdown 
completion. That's less complex and makes the intent clear.

like this:

visornic_serverdown(struct visornic_devdata *devdata,
		    visorbus_state_complete_func complete_func)
{
	unsigned long flags;
	int retval = 0;
	bool complete_serverdown = false;

	spin_lock_irqsave(&devdata->priv_lock, flags);
	if (!devdata->server_down && !devdata->server_change_state) {
		if (devdata->going_away) {
			dev_dbg(&devdata->dev->device,
				"%s aborting because device removal pending\n",
				__func__);
			retval = -ENODEV;
		} else {
			devdata->server_change_state = true;
			devdata->server_down_complete_func = complete_func;
			complete_serverdown = true;
		}
	} else if (devdata->server_change_state) {
		dev_dbg(&devdata->dev->device, "%s changing state\n",
			__func__);
		spin_unlock_irqrestore(&devdata->priv_lock, flags);
		retval = -EINVAL;
	} 		
	spin_unlock_irqrestore(&devdata->priv_lock, flags);
	
	if (complete_serverdown)
		visornic_serverdown_complete(devdata);

	return retval;
}

-- Ben