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SubjectRe: [PATCH] remove redundant NULL pointer checks prior to calling kfree() in fs/nfsd/
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On Fri, 2005-03-25 at 17:34 -0500, linux-os wrote:
> On Fri, 25 Mar 2005, Jesper Juhl wrote:
>
> > (please keep me on CC)
> >
> >
> > checking for NULL before calling kfree() is redundant and needlessly
> > enlarges the kernel image, let's get rid of those checks.
> >
>
> Hardly. ORing a value with itself and jumping on condition is
> real cheap compared with pushing a value into the stack

which century are you from?
"jumping on condition" can easily be 100+ cycles, depending on how
effective the branch predictor is. Pushing a value onto the stack otoh
is half a cycle.

Your argument was right probably in 1994, when cpus didn't do
speculation and out of order execution...


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