[PATCH 1/2] powerpc/kexec: Reset secondary cpu endianess before kexec
scottwood at freescale.com
Fri Jul 10 06:27:37 AEST 2015
On Thu, 2015-07-09 at 10:42 -0500, Segher Boessenkool wrote:
> On Tue, Jul 07, 2015 at 11:22:08PM -0500, Scott Wood wrote:
> > > I agree about using labels, but "bcl 20,31,foo" is not the same thing
> > > as "bl foo". The former is a form of bl that doesn't perturb the link
> > > stack and is therefore better for performance when you're not going to
> > > do a matching blr later (not that performance is at all critical
> > > here).
> > If performance mattered I would have complained about the extra mfmsr. :-)
> > I see that some other parts of the kernel are using that bcl instruction,
> > but
> > if it is actually worthwhile in those places, it'd be nice to at least
> > stick
> > it in a macro for readability...
> How is that going to help? It's just idiom; replacing it with some other
> idiom only means people already used to the 20,31 thing (which is quite old
> by now, btw.; 74xx days) will have to learn the new thing.
That's fine for people who are used to it (especially if it's the only number-
based bc they routinely come across), but I had to look up what it meant.
Simplified mnemonics exist for a reason.
> Unless you can think of a nice short name that can even be made an extended
For a macro I was thinking "BL_NORET" but for a mnemonic it'd probably be
shortened to something like "blnr".
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