On Tue, Jun 04, 2024 at 07:09:11PM +0200, John Paul Adrian Glaubitz wrote: > Hello, > > On Tue, 2024-06-04 at 10:04 -0700, Paul E. McKenney wrote: > > Use the new cmpxchg_emu_u8() to emulate one-byte cmpxchg() on sh. > > > > [ paulmck: Drop two-byte support per Arnd Bergmann feedback. ] > > [ paulmck: Apply feedback from Naresh Kamboju. ] > > [ Apply Geert Uytterhoeven feedback. ] > > > > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx> > > Cc: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx> > > Cc: Palmer Dabbelt <palmer@xxxxxxxxxxxx> > > Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx> > > Cc: Arnd Bergmann <arnd@xxxxxxxx> > > Cc: <linux-sh@xxxxxxxxxxxxxxx> > > --- > > arch/sh/Kconfig | 1 + > > arch/sh/include/asm/cmpxchg.h | 3 +++ > > 2 files changed, 4 insertions(+) > > > > diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig > > index 5e6a3ead51fb1..f723e2256c9c1 100644 > > --- a/arch/sh/Kconfig > > +++ b/arch/sh/Kconfig > > @@ -16,6 +16,7 @@ config SUPERH > > select ARCH_HIBERNATION_POSSIBLE if MMU > > select ARCH_MIGHT_HAVE_PC_PARPORT > > select ARCH_WANT_IPC_PARSE_VERSION > > + select ARCH_NEED_CMPXCHG_1_EMU > > select CPU_NO_EFFICIENT_FFS > > select DMA_DECLARE_COHERENT > > select GENERIC_ATOMIC64 > > diff --git a/arch/sh/include/asm/cmpxchg.h b/arch/sh/include/asm/cmpxchg.h > > index 5d617b3ef78f7..1e5dc5ccf7bf5 100644 > > --- a/arch/sh/include/asm/cmpxchg.h > > +++ b/arch/sh/include/asm/cmpxchg.h > > @@ -9,6 +9,7 @@ > > > > #include <linux/compiler.h> > > #include <linux/types.h> > > +#include <linux/cmpxchg-emu.h> > > > > #if defined(CONFIG_GUSA_RB) > > #include <asm/cmpxchg-grb.h> > > @@ -56,6 +57,8 @@ static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old, > > unsigned long new, int size) > > { > > switch (size) { > > + case 1: > > + return cmpxchg_emu_u8(ptr, old, new); > > case 4: > > return __cmpxchg_u32(ptr, old, new); > > } > > Reviewed-by: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx> > > I can pick this up through my SH tree unless someone insists this to > go through some other tree. Please do take it, and thank you! When I see it in -next, I will drop it from my tree. > Adrian > > PS: I'm a bit stumped that I'm not CC'ed as the SH maintainer. Me too, now that you mention it. I did generate the list some time back, but "git blame" shows you being maintainer for more than a year. Yet I do have the linux-sh email list, so it is unlikely that I pasted the get_maintainer.pl output from the wrong commit. I am forced to hypothesize that I fat-fingered the output of get_maintainer.pl when adding the Cc lines to that commit. Please accept my apologies for having left you out! Thanx, Paul