diff mbox

[Xen-devel,13/17] xen: arm64: asm: remove redundant "cc" clobbers

Message ID 1395330365-9901-13-git-send-email-ian.campbell@citrix.com
State Superseded
Headers show

Commit Message

Ian Campbell March 20, 2014, 3:46 p.m. UTC 
This resyncs atomics and cmpxchgs with Linux v3.14-rc7 by importing:
commit 95c4189689f92fba7ecf9097173404d4928c6e9b
Author: Will Deacon <will.deacon@arm.com>
Date:   Tue Feb 4 12:29:13 2014 +0000

    arm64: asm: remove redundant "cc" clobbers

    cbnz/tbnz don't update the condition flags, so remove the "cc" clobbers
    from inline asm blocks that only use these instructions to implement
    conditional branches.

    Signed-off-by: Will Deacon <will.deacon@arm.com>
    Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
 xen/include/asm-arm/arm64/atomic.h   |   12 +++++-------
 xen/include/asm-arm/arm64/spinlock.h |    6 +++---
 xen/include/asm-arm/arm64/system.h   |    8 ++++----
 3 files changed, 12 insertions(+), 14 deletions(-)

Comments

Julien Grall March 20, 2014, 5:45 p.m. UTC | #1 
On 03/20/2014 03:46 PM, Ian Campbell wrote:
> This resyncs atomics and cmpxchgs with Linux v3.14-rc7 by importing:
> commit 95c4189689f92fba7ecf9097173404d4928c6e9b
> Author: Will Deacon <will.deacon@arm.com>
> Date:   Tue Feb 4 12:29:13 2014 +0000
> 
>     arm64: asm: remove redundant "cc" clobbers
> 
>     cbnz/tbnz don't update the condition flags, so remove the "cc" clobbers
>     from inline asm blocks that only use these instructions to implement
>     conditional branches.
> 
>     Signed-off-by: Will Deacon <will.deacon@arm.com>
>     Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
> 
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Julien Grall <julien.grall@linaro.org>
diff mbox

Patch

diff --git a/xen/include/asm-arm/arm64/atomic.h b/xen/include/asm-arm/arm64/atomic.h
index 3f37ed5..b5d50f2 100644
--- a/xen/include/asm-arm/arm64/atomic.h
+++ b/xen/include/asm-arm/arm64/atomic.h
@@ -38,8 +38,7 @@  static inline void atomic_add(int i, atomic_t *v)
 "	stxr	%w1, %w0, %2\n"
 "	cbnz	%w1, 1b"
 	: "=&r" (result), "=&r" (tmp), "+Q" (v->counter)
-	: "Ir" (i)
-	: "cc");
+	: "Ir" (i));
 }
 
 static inline int atomic_add_return(int i, atomic_t *v)
@@ -54,7 +53,7 @@  static inline int atomic_add_return(int i, atomic_t *v)
 "	cbnz	%w1, 1b"
 	: "=&r" (result), "=&r" (tmp), "+Q" (v->counter)
 	: "Ir" (i)
-	: "cc", "memory");
+	: "memory");
 
 	smp_mb();
 	return result;
@@ -71,8 +70,7 @@  static inline void atomic_sub(int i, atomic_t *v)
 "	stxr	%w1, %w0, %2\n"
 "	cbnz	%w1, 1b"
 	: "=&r" (result), "=&r" (tmp), "+Q" (v->counter)
-	: "Ir" (i)
-	: "cc");
+	: "Ir" (i));
 }
 
 static inline int atomic_sub_return(int i, atomic_t *v)
@@ -87,7 +85,7 @@  static inline int atomic_sub_return(int i, atomic_t *v)
 "	cbnz	%w1, 1b"
 	: "=&r" (result), "=&r" (tmp), "+Q" (v->counter)
 	: "Ir" (i)
-	: "cc", "memory");
+	: "memory");
 
 	smp_mb();
 	return result;
@@ -109,7 +107,7 @@  static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new)
 "2:"
 	: "=&r" (tmp), "=&r" (oldval), "+Q" (ptr->counter)
 	: "Ir" (old), "r" (new)
-	: "cc", "memory");
+	: "cc");
 
 	smp_mb();
 	return oldval;
diff --git a/xen/include/asm-arm/arm64/spinlock.h b/xen/include/asm-arm/arm64/spinlock.h
index 3a36cfd..04300bc 100644
--- a/xen/include/asm-arm/arm64/spinlock.h
+++ b/xen/include/asm-arm/arm64/spinlock.h
@@ -70,7 +70,7 @@  static always_inline int _raw_read_trylock(raw_rwlock_t *rw)
         "1:\n"
         : "=&r" (tmp), "+r" (tmp2), "+Q" (rw->lock)
         :
-        : "cc", "memory");
+        : "memory");
 
     return !tmp2;
 }
@@ -86,7 +86,7 @@  static always_inline int _raw_write_trylock(raw_rwlock_t *rw)
         "1:\n"
         : "=&r" (tmp), "+Q" (rw->lock)
         : "r" (0x80000000)
-        : "cc", "memory");
+        : "memory");
 
     return !tmp;
 }
@@ -102,7 +102,7 @@  static inline void _raw_read_unlock(raw_rwlock_t *rw)
         "       cbnz    %w1, 1b\n"
         : "=&r" (tmp), "=&r" (tmp2), "+Q" (rw->lock)
         :
-        : "cc", "memory");
+        : "memory");
 }
 
 static inline void _raw_write_unlock(raw_rwlock_t *rw)
diff --git a/xen/include/asm-arm/arm64/system.h b/xen/include/asm-arm/arm64/system.h
index 9fa698b..fa50ead 100644
--- a/xen/include/asm-arm/arm64/system.h
+++ b/xen/include/asm-arm/arm64/system.h
@@ -16,7 +16,7 @@  static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size
 		"	cbnz	%w1, 1b\n"
 			: "=&r" (ret), "=&r" (tmp), "+Q" (*(u8 *)ptr)
 			: "r" (x)
-			: "cc", "memory");
+			: "memory");
 		break;
 	case 2:
 		asm volatile("//	__xchg2\n"
@@ -25,7 +25,7 @@  static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size
 		"	cbnz	%w1, 1b\n"
 			: "=&r" (ret), "=&r" (tmp), "+Q" (*(u16 *)ptr)
 			: "r" (x)
-			: "cc", "memory");
+			: "memory");
 		break;
 	case 4:
 		asm volatile("//	__xchg4\n"
@@ -34,7 +34,7 @@  static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size
 		"	cbnz	%w1, 1b\n"
 			: "=&r" (ret), "=&r" (tmp), "+Q" (*(u32 *)ptr)
 			: "r" (x)
-			: "cc", "memory");
+			: "memory");
 		break;
 	case 8:
 		asm volatile("//	__xchg8\n"
@@ -43,7 +43,7 @@  static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size
 		"	cbnz	%w1, 1b\n"
 			: "=&r" (ret), "=&r" (tmp), "+Q" (*(u64 *)ptr)
 			: "r" (x)
-			: "cc", "memory");
+			: "memory");
 		break;
 	default:
 		__bad_xchg(ptr, size), ret = 0;