Re: [PATCH 0/5] Provide two-byte cmpxchg() emulation

[Bradley Morgan]

On 7 October 2026 21:36:01 BST, "Paul E. McKenney" <paulmck@xxxxxxxxxx>
wrote:
>Hello!

[OFF-LIST]

I mean, I did what you wanted, hmm?

>
>This series provides emulation of two-byte cmpxchg().  Note that this
>does not (yet) allow free use of atomic operations on two-byte operands
>in core code because there are still a few supported systems that do not
>have two-byte store instructions.  However, this emulation does permit use
>of wide range of two-byte atomic operations, so is worth putting forward.
>
>This series is being reposted on request in order to ease testing efforts.
>
>The individual patches are as follows:
>
>1.	Add two-byte cmpxchg emulation function, courtesy of Bradley
>	Morgan.
>
>2.	sh: Emulate two-byte cmpxchg, courtesy of Bradley Morgan.
>
>3.	ARC: Emulate two-byte cmpxchg, courtesy of Bradley Morgan.
>
>4.	csky: Emulate two-byte cmpxchg, courtesy of Bradley Morgan.
>
>5.	xtensa: Emulate two-byte cmpxchg, courtesy of Bradley Morgan.
>
>#1 and #2 have the acks required to go into the upcoming v7.4 merge
>window.
>
>						Thanx, Paul
>
>------------------------------------------------------------------------
>
> arch/arc/include/asm/cmpxchg.h    |    3 +++
> arch/csky/include/asm/cmpxchg.h   |    9 +++++++++
> arch/sh/include/asm/cmpxchg.h     |    2 ++
> arch/xtensa/include/asm/cmpxchg.h |    1 +
> include/linux/cmpxchg-emu.h       |    4 +++-
> lib/cmpxchg-emu.c                 |   38
> ++++++++++++++++++++++++++++++++++----
> 6 files changed, 52 insertions(+), 5 deletions(-)

--- Thanks!
"I'm not a very positive person" - Linus torvalds