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SubjectRe: [PATCH] WARN_ONCE(): use bool for boolean flag
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On Sun, 2009-09-27 at 14:24 -0300, Cesar Eduardo Barros wrote:

> I took a quick look, and all uses seem to be directly in a boolean
> context (within an if()), so there would be no problem. Besides, the
> unlikely() all these macros end with does a double negation, meaning
> even if it is an int, it will be either 0 or 1 (but I am not sure I am
> reading these macros right - it seems CONFIG_TRACE_BRANCH_PROFILING
> turns all unlikely() into likely()).
>
> In fact, I was expecting no change at all, since gcc should be able to
> see it is being treated as a boolean (perhaps I am trusting gcc too
> much). And to make matters even more confusing, my own test changing all
> __ret_warn_once to bool and dropping the !! caused an _increase_ of 598
> bytes (x86-64 defconfig).
>
> text data bss dec hex filename
> 8100553 1207148 991988 10299689 9d2929 vmlinux.warnret.before
> 8101119 1207180 991988 10300287 9d2b7f vmlinux.warnret.after
>
> (And yes, data increased again.)

Did you have the CONFIG_TRACE_BRANCH_PROFILING option enabled for the
test above?

If this was just your regular base line config , then that is odd .. I
also would think worse case would be no size reduction .. I did my
compile test on x86-32 btw..

Daniel

Daniel



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