lkml.org 
[lkml]   [2024]   [Apr]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH RFC cmpxchg 6/8] xtensa: Emulate one-byte and two-byte cmpxchg
Date
Use the new cmpxchg_emu_u8() and cmpxchg_emu_u16() to emulate one-byte
and two-byte cmpxchg() on xtensa.

[ paulmck: Apply kernel test robot feedback. ]

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
---
arch/xtensa/Kconfig | 1 +
arch/xtensa/include/asm/cmpxchg.h | 3 +++
2 files changed, 4 insertions(+)

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index f200a4ec044e6..8131f0d75bb58 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -14,6 +14,7 @@ config XTENSA
select ARCH_HAS_DMA_SET_UNCACHED if MMU
select ARCH_HAS_STRNCPY_FROM_USER if !KASAN
select ARCH_HAS_STRNLEN_USER
+ select ARCH_NEED_CMPXCHG_1_2_EMU
select ARCH_USE_MEMTEST
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
diff --git a/arch/xtensa/include/asm/cmpxchg.h b/arch/xtensa/include/asm/cmpxchg.h
index 675a11ea8de76..a0f9a2070209b 100644
--- a/arch/xtensa/include/asm/cmpxchg.h
+++ b/arch/xtensa/include/asm/cmpxchg.h
@@ -15,6 +15,7 @@

#include <linux/bits.h>
#include <linux/stringify.h>
+#include <linux/cmpxchg-emu.h>

/*
* cmpxchg
@@ -74,6 +75,8 @@ static __inline__ unsigned long
__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
{
switch (size) {
+ case 1: return cmpxchg_emu_u8((volatile u8 *)ptr, old, new);
+ case 2: return cmpxchg_emu_u16((volatile u16 *)ptr, old, new);
case 4: return __cmpxchg_u32(ptr, old, new);
default: __cmpxchg_called_with_bad_pointer();
return old;
--
2.40.1

\
 
 \ /
  Last update: 2024-05-27 16:18    [W:0.505 / U:0.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site