Re: [PATCH] no need to check for NULL before calling kfree() -fs/ext2/

[Dave Jones <davej@redhat.com>]

On Sun, Mar 27, 2005 at 05:12:58PM +0200, Jan Engelhardt wrote:

 > Well, kfree inlined was already mentioned but forgotten again.
 > What if this was used:
 > 
 > inline static void kfree_WRAP(void *addr) {
 >     if(likely(addr != NULL)) {
 >         kfree_real(addr);
 >     }
 >     return;
 > }
 > 
 > And remove the NULL-test in kfree_real()? Then we would have:

Am I the only person who is completely fascinated by the
effort being spent here micro-optimising something thats
almost never in a path that needs optimising ?
I'd be amazed if any of this masturbation showed the tiniest
blip on a real workload, or even on a benchmark other than
one crafted specifically to test kfree in a loop.

That each occurance of this 'optimisation' also saves a handful
of bytes in generated code is it's only real benefit afaics.
Even then, if a functions cache performance is better off because
we trimmed a few bytes from the tail of a function, I'd be
completely amazed.

I guess April 1st came early this year.

		Dave

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