diff mbox series

[v2,07/21] x86/io: Remove useless definition of mmiowb()

Message ID 20190405135936.7266-8-will.deacon@arm.com
State Accepted
Commit 08f1f3a72f4cea136686585b81a251baa3539f12
Headers show
Series Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb()) | expand

Commit Message

Will Deacon April 5, 2019, 1:59 p.m. UTC
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@arm.com>

---
 arch/x86/include/asm/io.h | 2 --
 1 file changed, 2 deletions(-)

-- 
2.11.0

Comments

Thomas Gleixner April 5, 2019, 2:14 p.m. UTC | #1
On Fri, 5 Apr 2019, Will Deacon wrote:

> 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


s/we can//

> definition entirely and pick up the dummy definition from core code.

> 

> Signed-off-by: Will Deacon <will.deacon@arm.com>


Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
diff mbox series

Patch

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")