Re: [PATCH] locking/atomic: sh: Use generic_cmpxchg_local for arch_cmpxchg_local()
From: Mark Rutland <mark.rutland@arm.com>
Date: 2023-10-24 15:08:26
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linux-sh, lkml
On Tue, Oct 24, 2023 at 11:52:54PM +0900, Masami Hiramatsu (Google) wrote:
From: Masami Hiramatsu (Google) <mhiramat@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>. I think the right thing to do here is to define arch_cmpxchg_local() in terms of arch_cmpxchg(), i.e. at the bottom of arch/sh's <asm/cmpxchg.h> add: #define arch_cmpxchg_local arch_cmpxchg Mark.
quoted hunk ↗ jump to hunk
Reported-by: kernel test robot <redacted> Closes: https://lore.kernel.org/oe-kbuild-all/202310241310.Ir5uukOG-lkp@intel.com/ (local) Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> --- arch/sh/include/asm/cmpxchg.h | 2 ++ 1 file changed, 2 insertions(+)diff --git a/arch/sh/include/asm/cmpxchg.h b/arch/sh/include/asm/cmpxchg.h index 288f6f38d98f..e920e61fb817 100644 --- a/arch/sh/include/asm/cmpxchg.h +++ b/arch/sh/include/asm/cmpxchg.h@@ -71,4 +71,6 @@ static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old, (unsigned long)_n_, sizeof(*(ptr))); \ }) +#include <asm-generic/cmpxchg-local.h> + #endif /* __ASM_SH_CMPXCHG_H */