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Re: [PATCH] Linux Kernel Markers 0.7 for 2.6.17 (with type checking!)


* Jeremy Fitzhardinge (jeremy@goop.org) wrote:
> Mathieu Desnoyers wrote:
> >#define MARK_SYM(name) \
> >        do { \
> >                __label__ here; \
> >                volatile static void *__mark_kprobe_##name \
> >                        asm (MARK_CALL_PREFIX#name) \
> >                        __attribute__((unused)) = &&here; \
> >here: \
> >                do { } while(0); \
> >        } while(0)
> >
> >Which fixes the problem. Some tests showed me that the compiler does not 
> >unroll
> >an otherwise unrolled loop when this specific macro is called. (test done 
> >with
> >-funroll-all-loops).
> 
> Eh?  I thought you wanted to avoid changing the generated code?  
> Inhibiting loop unrolling could be a pretty large change...
> 

>From what I see in 2.6.17/2.6.18 makefiles, only -OS and -O2 are generally 
used by the build system (no -O3) and there is not use of -funroll-loops. I
guess it must not be so useful in this context.

Mathieu


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