From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH 7/7] alpha: lazy FPU switching
Date: Sat, 30 Oct 2021 22:13:08 +0000
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To: "Maciej W. Rozycki" <macro@orcam.me.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>, alpha <linux-alpha@vger.kernel.org>

On Sat, Oct 30, 2021 at 10:25:34PM +0100, Maciej W. Rozycki wrote:
> On Sat, 30 Oct 2021, Al Viro wrote:
> 
> > 1) lazy FPU part has a braino in it; __save_fpu() in alpha_fork() et.al. should
> > be called *after* do_switch_stack(), not before it.  Another (minor) problem is
> > that use of jsr for calls for functions in the same object file is stupid -
> > should be bsr instead.  Not a bug, per se, but it's clearly suboptimal.  Both
> > fixes folded.
> 
>  The linker is supposed to relax any eligible JSR to BSR (same with JMP vs 
> BR) so it shouldn't really matter, and writing it down as JSR is surely 
> more flexible as you don't have to track which caller/callee is where.

All within arch/alpha/kernel/entry.S.  If that ever grows past 1M insns, we
have much worse problems...  Other callers are from C, so they all end up
with jsr, obviously.