Messages in this thread | | | Subject | Re: [PATCH] WARN_ONCE(): use bool for boolean flag | From | Daniel Walker <> | Date | Sun, 27 Sep 2009 10:32:40 -0700 |
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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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