Re: [tip:perf/uprobes] uprobes/core: Clean up, refactor and improvethe code

[Ingo Molnar]

* Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx> wrote:

> The volatiles were added to arch/x86/kernel/kprobes.c because 
> of commit 7115e3fcf45 and 315eb8a2a1b. The volatiles are 
> required because gcc 4.6 gave a warning about the asm operand 
> for test_bit.  So the same were added to 
> arch/x86/kernel/uprobes.c.

Seems like a GCC bug - a bogus warning - or does it generate bad 
code as well?

In any case, kprobes.c did it correctly, it added the volatile 
*and a comment*, pointing out that it's a GCC bug. No such 
warning was added to uprobes.c, making the volatile look 
entirely spurious.

So feel free to re-add the volatile in a followup patch, just 
make sure the GCC workaround nature is documented.

Thanks,

	Ingo
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