Re: [PATCH 2/2] powerpc: Switch to generic WARN_ON()/BUG_ON()

Kyle McMartin
2007-10-12T02:04:31Z

On Fri, Oct 12, 2007 at 11:23:39AM +1000, Paul Mackerras wrote:
> Olof Johansson writes:
>
> > Not using the ppc-specific WARN_ON/BUG_ON constructs actually saves about
> > 4K text on a ppc64_defconfig. The main reason seems to be that prepping
> > the arguments to the conditional trap instructions is more work than
> > just doing a compare and branch.
>
> It might be more instructions but it takes fewer cycles, I would
> expect. Do you have the actual instruction sequences to compare?
>

I really hope WARN_ON/BUG_ON aren't hotpaths on powerpc. ;-)

Cheers,
Kyle