Re: [PATCH v9 02/10] Makefile: Prepare for using macros for inline asm

[Logan Gunthorpe]

On 2018-11-07 11:01 a.m., Nadav Amit wrote:
> Ideas? Do people care about it?

Just spit balling, but is there a reason we didn't just put the macros
for inline assembly directly in the header? Something like this:

asm(".macro ANNOTATE_UNREACHABLE counter:req\n\t"
    "\\counter:\n\t"
        ".pushsection .discard.unreachable\n\t"
        ".long \\counter\\()b -.\n\t"
        ".popsection\n\t"
    ".endm\n");

#define annotate_unreachable() ({                   \
    asm volatile("ANNOTATE_UNREACHABLE counter=%c0" \
                 : : "i" (__COUNTER__));            \
})

It does mean the macros won't be usable in non-inline assembly, without
duplicating them, but do we care about that?

I would have expected people compiling the kernel with distcc to be
fairly common -- it certainly speeds up my kernel compiles quite
significantly and thus saves me a lot of time.

Logan