[tip: x86/percpu] x86/percpu: Move raw_percpu_xchg_op() to a better place

[tip-bot2 for Uros Bizjak]

The following commit has been merged into the x86/percpu branch of tip:

Commit-ID:     ce99b9c8daff3352a2ae0c72acf44e0663095fea
Gitweb:        https://git.kernel.org/tip/ce99b9c8daff3352a2ae0c72acf44e0663095fea
Author:        Uros Bizjak <ubizjak@xxxxxxxxx>
AuthorDate:    Wed, 20 Mar 2024 09:30:41 +01:00
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Wed, 20 Mar 2024 12:29:17 +01:00

x86/percpu: Move raw_percpu_xchg_op() to a better place

Move raw_percpu_xchg_op() together with this_percpu_xchg_op()
and trivially rename some internal variables to harmonize them
between macro implementations.

No functional changes intended.

Signed-off-by: Uros Bizjak <ubizjak@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240320083127.493250-2-ubizjak@xxxxxxxxx
---
 arch/x86/include/asm/percpu.h | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
index de991e6..7563e69 100644
--- a/arch/x86/include/asm/percpu.h
+++ b/arch/x86/include/asm/percpu.h
@@ -230,6 +230,17 @@ do {									\
 })
 
 /*
+ * raw_cpu_xchg() can use a load-store since
+ * it is not required to be IRQ-safe.
+ */
+#define raw_percpu_xchg_op(_var, _nval)					\
+({									\
+	typeof(_var) pxo_old__ = raw_cpu_read(_var);			\
+	raw_cpu_write(_var, _nval);					\
+	pxo_old__;							\
+})
+
+/*
  * this_cpu_xchg() is implemented using cmpxchg without a lock prefix.
  * xchg is expensive due to the implied lock prefix. The processor
  * cannot prefetch cachelines if xchg is used.
@@ -499,18 +510,6 @@ do {									\
 #define raw_cpu_or_1(pcp, val)		percpu_to_op(1, , "or", (pcp), val)
 #define raw_cpu_or_2(pcp, val)		percpu_to_op(2, , "or", (pcp), val)
 #define raw_cpu_or_4(pcp, val)		percpu_to_op(4, , "or", (pcp), val)
-
-/*
- * raw_cpu_xchg() can use a load-store since it is not required to be
- * IRQ-safe.
- */
-#define raw_percpu_xchg_op(var, nval)					\
-({									\
-	typeof(var) pxo_ret__ = raw_cpu_read(var);			\
-	raw_cpu_write(var, (nval));					\
-	pxo_ret__;							\
-})
-
 #define raw_cpu_xchg_1(pcp, val)	raw_percpu_xchg_op(pcp, val)
 #define raw_cpu_xchg_2(pcp, val)	raw_percpu_xchg_op(pcp, val)
 #define raw_cpu_xchg_4(pcp, val)	raw_percpu_xchg_op(pcp, val)