Pekka wrote:
> (4) The cleanups Jesper and others are doing are to remove the
> _redundant_ NULL checks (i.e. it is now checked twice).
Even such obvious changes as removing redundant checks doesn't
seem to ensure a performance improvement. Jesper Juhl posted
performance data for such changes in his microbenchmark a couple
of days ago.
As I posted then, I could swear that his numbers show:
> Just looking at the third run, it seems to me that "if (likely(p))
> kfree(p);" beats a naked "kfree(p);" everytime, whether p is half
> NULL's, or very few NULL's, or almost all NULL's.
Twice now I have asked Jesper to explain this strange result.
I have heard no explanation (not even a terse "you idiot ;)"),
nor anyone else comment on these numbers.
Maybe we should be following your good advice:
> You don't know that until you profile!
instead of continuing to make these code changes.
--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <[EMAIL PROTECTED]> 1.650.933.1373,
1.925.600.0401
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