[PATCH v6 7/9] sparc: qspinlock: Add ARCH_USE_QUEUED_SPINLOCKS_XCHG32

guoren
2021-03-31T14:32:58Z

From: Guo Ren <guoren@linux.alibaba.com>

We don't have native hw xchg16 instruction, so let qspinlock
generic code to deal with it.

Using the full-word atomic xchg instructions implement xchg16 has
the semantic risk for atomic operations.

This patch cancels the dependency of on qspinlock generic code on
architecture's xchg16.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Rob Gardner <rob.gardner@oracle.com>
---
arch/sparc/Kconfig | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 164a5254c91c..1079fe3f058c 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -91,6 +91,7 @@ config SPARC64
select HAVE_REGS_AND_STACK_ACCESS_API
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
+ select ARCH_USE_QUEUED_SPINLOCKS_XCHG32
select GENERIC_TIME_VSYSCALL
select ARCH_CLOCKSOURCE_DATA
select ARCH_HAS_PTE_SPECIAL