Re: [patch 2/4] net: use mutex_is_locked() for ASSERT_RTNL()

[Jarek Poplawski <jarkao2@gmail.com>]

On Mon, Dec 17, 2007 at 03:31:33PM +0800, Herbert Xu wrote:
> On Mon, Dec 17, 2007 at 08:26:01AM +0100, Jarek Poplawski wrote:
> >
> > Btw. #2: David Miller gave this example of ASSERT_RTNL use:
> > 
> > 	ASSERT_RTNL();
> > 	page = alloc_page(GFP_KERNEL);
> > 
> > But isn't there a debugging duplication: it seems alloc_page() is used
> > in so many places and this check for GFP is/should_be there already?
> 
> On some paths this may be buried a conditional.  Also if you
> replace it with a mutex_is_locked without the may_sleep it won't
> catch the case that started all this, namely the promiscuous path.
> 

Right! There is only a question how much is such cases vs. checked
already, because then a might_sleep is really more readable when
added explicitly.

Jarek P.