Messages in this thread Patch in this message | | | From | Arnd Bergmann <> | Subject | [PATCH v2 05/13] powerpc: use linux/unaligned/le_struct.h on LE power7 | Date | Fri, 14 May 2021 12:00:53 +0200 |
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From: Arnd Bergmann <arnd@arndb.de>
Little-endian POWER7 kernels disable CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS because that is not supported on the hardware, but the kernel still uses direct load/store for explicti get_unaligned()/put_unaligned().
I assume this is a mistake that leads to power7 having to trap and fix up all these unaligned accesses at a noticeable performance cost.
The fix is completely trivial, just remove the file and use the generic version that gets it right.
Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- arch/powerpc/include/asm/unaligned.h | 22 ---------------------- 1 file changed, 22 deletions(-) delete mode 100644 arch/powerpc/include/asm/unaligned.h
diff --git a/arch/powerpc/include/asm/unaligned.h b/arch/powerpc/include/asm/unaligned.h deleted file mode 100644 index ce69c5eff95e..000000000000 --- a/arch/powerpc/include/asm/unaligned.h +++ /dev/null @@ -1,22 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _ASM_POWERPC_UNALIGNED_H -#define _ASM_POWERPC_UNALIGNED_H - -#ifdef __KERNEL__ - -/* - * The PowerPC can do unaligned accesses itself based on its endian mode. - */ -#include <linux/unaligned/access_ok.h> -#include <linux/unaligned/generic.h> - -#ifdef __LITTLE_ENDIAN__ -#define get_unaligned __get_unaligned_le -#define put_unaligned __put_unaligned_le -#else -#define get_unaligned __get_unaligned_be -#define put_unaligned __put_unaligned_be -#endif - -#endif /* __KERNEL__ */ -#endif /* _ASM_POWERPC_UNALIGNED_H */ -- 2.29.2
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