From: "Paul E. McKenney" <paulmck@kernel.org>
To: linux-kernel@vger.kernel.org
Cc: kernel-team@meta.com, "Paul E. McKenney" <paulmck@kernel.org>,
Guo Ren <guoren@kernel.org>,
linux-csky@vger.kernel.org
Subject: [PATCH RFC cmpxchg 4/8] csky: Emulate one-byte and two-byte cmpxchg
Date: Mon, 1 Apr 2024 14:39:46 -0700 [thread overview]
Message-ID: <20240401213950.3910531-4-paulmck@kernel.org> (raw)
In-Reply-To: <31c82dcc-e203-48a9-aadd-f2fcd57d94c1@paulmck-laptop>
Use the new cmpxchg_emu_u8() and cmpxchg_emu_u16() to emulate one-byte
and two-byte cmpxchg() on csky.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: <linux-csky@vger.kernel.org>
---
arch/csky/Kconfig | 1 +
arch/csky/include/asm/cmpxchg.h | 18 ++++++++++++++++++
2 files changed, 19 insertions(+)
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index d3ac36751ad1f..860d4e02d6295 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -37,6 +37,7 @@ config CSKY
select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
+ select ARCH_NEED_CMPXCHG_1_2_EMU
select ARCH_WANT_FRAME_POINTERS if !CPU_CK610 && $(cc-option,-mbacktrace)
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
select COMMON_CLK
diff --git a/arch/csky/include/asm/cmpxchg.h b/arch/csky/include/asm/cmpxchg.h
index 916043b845f14..848a8691c5a2a 100644
--- a/arch/csky/include/asm/cmpxchg.h
+++ b/arch/csky/include/asm/cmpxchg.h
@@ -61,6 +61,12 @@
__typeof__(old) __old = (old); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
+ case 1: \
+ __ret = cmpxchg_emu_u8((volatile u8 *)__ptr, __old, __new); \
+ break; \
+ case 2: \
+ __ret = cmpxchg_emu_u16((volatile u16 *)__ptr, __old, __new); \
+ break; \
case 4: \
asm volatile ( \
"1: ldex.w %0, (%3) \n" \
@@ -91,6 +97,12 @@
__typeof__(old) __old = (old); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
+ case 1: \
+ __ret = cmpxchg_emu_u8((volatile u8 *)__ptr, __old, __new); \
+ break; \
+ case 2: \
+ __ret = cmpxchg_emu_u16((volatile u16 *)__ptr, __old, __new); \
+ break; \
case 4: \
asm volatile ( \
"1: ldex.w %0, (%3) \n" \
@@ -122,6 +134,12 @@
__typeof__(old) __old = (old); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
+ case 1: \
+ __ret = cmpxchg_emu_u8((volatile u8 *)__ptr, __old, __new); \
+ break; \
+ case 2: \
+ __ret = cmpxchg_emu_u16((volatile u16 *)__ptr, __old, __new); \
+ break; \
case 4: \
asm volatile ( \
RELEASE_FENCE \
--
2.40.1
parent reply other threads:[~2024-04-01 21:39 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <31c82dcc-e203-48a9-aadd-f2fcd57d94c1@paulmck-laptop>]
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