Re: [PATCH] [BLUETOOTH] kmalloc + memset -> kzalloc conversion

[Marcel Holtmann <marcel@holtmann.org>]

Hi Paulo,

> >>>Confused.  This patch changes lots of block code, not bluetooth.
> >>
> >>I know. This is what I already mailed Deepak, but he never replied.
> > 
> > Sorry, got lost in the mailbox. I think I was not paying attention to
> > my tab completion and included the wrong patch. Proper patch follows.
> > 
> [...]
> > --- a/drivers/bluetooth/hci_usb.c
> > +++ b/drivers/bluetooth/hci_usb.c
> > @@ -134,10 +134,9 @@ static struct usb_device_id blacklist_id
> >  
> >  static struct _urb *_urb_alloc(int isoc, unsigned int __nocast gfp)
> >  {
> > -	struct _urb *_urb = kmalloc(sizeof(struct _urb) +
> > +	struct _urb *_urb = kzalloc(sizeof(struct _urb) +
> >  				sizeof(struct usb_iso_packet_descriptor) * isoc, gfp);
> >  	if (_urb) {
> > -		memset(_urb, 0, sizeof(*_urb));
> >  		usb_init_urb(&_urb->urb);
> >  	}
> >  	return _urb;
> 
> This one doesn't keep the exact same behavior as before, as it is 
> zeroing more memory than it did.
> 
> If this is not a performance critical path, then I guess it's ok (code 
> size reduction, and all).
> 
> I just wanted to call some attention on this so that someone more 
> knowledgeable than me in the bluetooth ways can make sure it's ok.

the current hci_usb URB shim layer is crap anyhow. We need to replace it
at some point with better code, but so far I haven't had the time to do
this properly.

Regards

Marcel