Re: [PATCH v2 09/10] arch: Remove cmpxchg_double

From
Hyeonggon Yoo <hidden>
Date
2023-02-08 13:46:09
Also in
linux-arch, linux-crypto, linux-iommu, linux-mm, linux-s390, lkml
Reply to
Peter Zijlstra, 2023-02-02
On Thu, Feb 02, 2023 at 03:50:39PM +0100, Peter Zijlstra wrote:
quoted hunk ↗ jump to hunk
No moar users, remove the monster.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
 Documentation/core-api/this_cpu_ops.rst    |    2 -
 arch/arm64/include/asm/atomic_ll_sc.h      |   33 ----------------
 arch/arm64/include/asm/atomic_lse.h        |   36 ------------------
 arch/arm64/include/asm/cmpxchg.h           |   46 -----------------------
 arch/arm64/include/asm/percpu.h            |   10 -----
 arch/s390/include/asm/cmpxchg.h            |   34 -----------------
 arch/s390/include/asm/percpu.h             |   18 ---------
 arch/x86/include/asm/cmpxchg.h             |   25 ------------
 arch/x86/include/asm/cmpxchg_32.h          |    1 
 arch/x86/include/asm/cmpxchg_64.h          |    1 
 arch/x86/include/asm/percpu.h              |   41 --------------------
 include/asm-generic/percpu.h               |   58 -----------------------------
 include/linux/atomic/atomic-instrumented.h |   17 --------
 include/linux/percpu-defs.h                |   38 -------------------
 scripts/atomic/gen-atomic-instrumented.sh  |   17 ++------
 15 files changed, 6 insertions(+), 371 deletions(-)
--- a/arch/x86/include/asm/cmpxchg.h
+++ b/arch/x86/include/asm/cmpxchg.h
--- a/arch/x86/include/asm/percpu.h
+++ b/arch/x86/include/asm/percpu.h
@@ -385,30 +368,6 @@ do {									\
 #define this_cpu_add_return_8(pcp, val)		percpu_add_return_op(8, volatile, pcp, val)
 #define this_cpu_xchg_8(pcp, nval)		percpu_xchg_op(8, volatile, pcp, nval)
 #define this_cpu_cmpxchg_8(pcp, oval, nval)	percpu_cmpxchg_op(8, volatile, pcp, oval, nval)
-
-/*
- * Pretty complex macro to generate cmpxchg16 instruction.  The instruction
- * is not supported on early AMD64 processors so we must be able to emulate
- * it in software.  The address used in the cmpxchg16 instruction must be
- * aligned to a 16 byte boundary.
- */
-#define percpu_cmpxchg16b_double(pcp1, pcp2, o1, o2, n1, n2)		\
-({									\
-	bool __ret;							\
-	typeof(pcp1) __o1 = (o1), __n1 = (n1);				\
-	typeof(pcp2) __o2 = (o2), __n2 = (n2);				\
-	alternative_io("leaq %P1,%%rsi\n\tcall this_cpu_cmpxchg16b_emu\n\t", \
I guess now arch/x86/lib/cmpxchg*b_emu.S could be dropped too?
quoted hunk ↗ jump to hunk
-		       "cmpxchg16b " __percpu_arg(1) "\n\tsetz %0\n\t",	\
-		       X86_FEATURE_CX16,				\
-		       ASM_OUTPUT2("=a" (__ret), "+m" (pcp1),		\
-				   "+m" (pcp2), "+d" (__o2)),		\
-		       "b" (__n1), "c" (__n2), "a" (__o1) : "rsi");	\
-	__ret;								\
-})
-
-#define raw_cpu_cmpxchg_double_8	percpu_cmpxchg16b_double
-#define this_cpu_cmpxchg_double_8	percpu_cmpxchg16b_double
-
 #endif
Thread (31 messages) 31 messages, 10 authors, last reply 2023-02-08
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