[RFC PATCH 06/20] x86: io: Remove useless definition of mmiowb()

From: Will Deacon
Date: Fri Feb 22 2019 - 13:50:58 EST


x86 maps mmiowb() to barrier(), but this is superfluous because a
compiler barrier is already implied by spin_unlock(). Since x86 also
includes asm-generic/io.h in its asm/io.h file, we can remove the
definition entirely and pick up the dummy definition from core code.

Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
---
arch/x86/include/asm/io.h | 2 --
1 file changed, 2 deletions(-)

diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 686247db3106..a06a9f8294ea 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -90,8 +90,6 @@ build_mmio_write(__writel, "l", unsigned int, "r", )
#define __raw_writew __writew
#define __raw_writel __writel

-#define mmiowb() barrier()
-
#ifdef CONFIG_X86_64

build_mmio_read(readq, "q", u64, "=r", :"memory")
--
2.11.0