On Wed, 2023-10-25 at 11:30 +0100, Mark Rutland wrote: > On Wed, Oct 25, 2023 at 08:42:55AM +0900, Masami Hiramatsu wrote: > > On Tue, 24 Oct 2023 16:08:12 +0100 > > Mark Rutland <mark.rutl...@arm.com> wrote: > > > > > On Tue, Oct 24, 2023 at 11:52:54PM +0900, Masami Hiramatsu (Google) wrote: > > > > From: Masami Hiramatsu (Google) <mhira...@kernel.org> > > > > > > > > Use generic_cmpxchg_local() for arch_cmpxchg_local() implementation > > > > in SH architecture because it does not implement arch_cmpxchg_local(). > > > > > > I do not think this is correct. > > > > > > The implementation in <asm-generic/cmpxchg-local.h> is UP-only (and it > > > only > > > disables interrupts), whereas arch/sh can be built SMP. We should > > > probably add > > > some guards into <asm-generic/cmpxchg-local.h> for that as we have in > > > <asm-generic/cmpxchg.h>. > > > > Isn't cmpxchg_local for the data which only needs to ensure to do cmpxchg > > on local CPU? > > So I think it doesn't care about the other CPUs (IOW, it should not touched > > by > > other CPUs), so it only considers UP case. E.g. on x86, > > arch_cmpxchg_local() is > > defined as raw "cmpxchg" without lock prefix. > > > > #define __cmpxchg_local(ptr, old, new, size) \ > > __raw_cmpxchg((ptr), (old), (new), (size), "") > > > > Yes, you're right; sorry for the noise. > > For your original patch: > > Acked-by: Mark Rutland <mark.rutl...@arm.com> >
Geert, what's your opinion on this? Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer `. `' Physicist `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913