From: Arun Sharma <asharma@fb.com>
To: linux-kernel@vger.kernel.org
Cc: Arun Sharma <asharma@fb.com>, Ingo Molnar <mingo@elte.hu>,
David Miller <davem@davemloft.net>, Andrew Morton <akpm@osdl.org>,
Eric Dumazet <eric.dumazet@gmail.com>
Subject: [PATCH 2/2] atomic: move atomic_add_unless to generic code
Date: Tue, 31 May 2011 12:10:46 -0700 [thread overview]
Message-ID: <1306869046-20172-2-git-send-email-asharma@fb.com> (raw)
In-Reply-To: <1306869046-20172-1-git-send-email-asharma@fb.com>
This is in preparation for more generic atomic
primitives based on __atomic_add_unless.
TODO: Need help with arch/avr32.
Signed-off-by: Arun Sharma <asharma@fb.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <20110531105019.GF24172@elte.hu>
---
arch/alpha/include/asm/atomic.h | 10 +++++-----
arch/arm/include/asm/atomic.h | 4 ++--
arch/avr32/include/asm/atomic.h | 6 +++---
arch/blackfin/include/asm/atomic.h | 4 ++--
arch/cris/include/asm/atomic.h | 4 ++--
arch/frv/include/asm/atomic.h | 4 ++--
arch/h8300/include/asm/atomic.h | 4 ++--
arch/ia64/include/asm/atomic.h | 4 ++--
arch/m32r/include/asm/atomic.h | 8 ++++----
arch/m68k/include/asm/atomic.h | 4 ++--
arch/mips/include/asm/atomic.h | 10 +++++-----
arch/mn10300/include/asm/atomic.h | 4 ++--
arch/parisc/include/asm/atomic.h | 10 +++++-----
arch/powerpc/include/asm/atomic.h | 14 +++++++-------
arch/s390/include/asm/atomic.h | 4 ++--
arch/sh/include/asm/atomic.h | 8 ++++----
arch/sparc/include/asm/atomic_32.h | 2 +-
arch/sparc/include/asm/atomic_64.h | 4 ++--
arch/tile/include/asm/atomic_32.h | 10 +++++-----
arch/tile/include/asm/atomic_64.h | 4 ++--
arch/x86/include/asm/atomic.h | 8 ++++----
arch/x86/include/asm/atomic64_32.h | 2 +-
arch/x86/include/asm/atomic64_64.h | 2 +-
arch/xtensa/include/asm/atomic.h | 8 ++++----
include/linux/atomic.h | 14 ++++++++++++++
25 files changed, 85 insertions(+), 71 deletions(-)
diff --git a/arch/alpha/include/asm/atomic.h b/arch/alpha/include/asm/atomic.h
index 88b7491..3d67049 100644
--- a/arch/alpha/include/asm/atomic.h
+++ b/arch/alpha/include/asm/atomic.h
@@ -176,15 +176,15 @@ static __inline__ long atomic64_sub_return(long i, atomic64_t * v)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
- * atomic_add_unless - add unless the number is a given value
+ * __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -196,7 +196,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
@@ -207,7 +207,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
{
diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h
index 4d501f1..3757e91 100644
--- a/arch/arm/include/asm/atomic.h
+++ b/arch/arm/include/asm/atomic.h
@@ -208,14 +208,14 @@ static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
c = old;
- return c != u;
+ return c;
}
#define atomic_inc(v) atomic_add(1, v)
diff --git a/arch/avr32/include/asm/atomic.h b/arch/avr32/include/asm/atomic.h
index f229c38..7216e91 100644
--- a/arch/avr32/include/asm/atomic.h
+++ b/arch/avr32/include/asm/atomic.h
@@ -108,7 +108,7 @@ static inline int atomic_sub_unless(atomic_t *v, int a, int u)
}
/*
- * atomic_add_unless - add unless the number is a given value
+ * __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
@@ -117,7 +117,7 @@ static inline int atomic_sub_unless(atomic_t *v, int a, int u)
* and returns non zero. If v is equal to u then it returns zero. This
* is done as an atomic operation.
*/
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int tmp, result;
@@ -126,7 +126,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
else {
result = 0;
asm volatile(
- "/* atomic_add_unless */\n"
+ "/* __atomic_add_unless */\n"
"1: ssrf 5\n"
" ld.w %0, %3\n"
" cp.w %0, %5\n"
diff --git a/arch/blackfin/include/asm/atomic.h b/arch/blackfin/include/asm/atomic.h
index 1fcc2a8..2cfce26 100644
--- a/arch/blackfin/include/asm/atomic.h
+++ b/arch/blackfin/include/asm/atomic.h
@@ -94,13 +94,13 @@ static inline int atomic_test_mask(int mask, atomic_t *v)
#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-#define atomic_add_unless(v, a, u) \
+#define __atomic_add_unless(v, a, u) \
({ \
int c, old; \
c = atomic_read(v); \
while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
c = old; \
- c != (u); \
+ c; \
})
/*
diff --git a/arch/cris/include/asm/atomic.h b/arch/cris/include/asm/atomic.h
index ce9f67e..7e90532 100644
--- a/arch/cris/include/asm/atomic.h
+++ b/arch/cris/include/asm/atomic.h
@@ -138,7 +138,7 @@ static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int ret;
unsigned long flags;
@@ -148,7 +148,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
if (ret != u)
v->counter += a;
cris_atomic_restore(v, flags);
- return ret != u;
+ return ret;
}
/* Atomic operations are already serializing */
diff --git a/arch/frv/include/asm/atomic.h b/arch/frv/include/asm/atomic.h
index b07b75f..a51dcdf 100644
--- a/arch/frv/include/asm/atomic.h
+++ b/arch/frv/include/asm/atomic.h
@@ -241,7 +241,7 @@ extern uint32_t __xchg_32(uint32_t i, volatile void *v);
#define atomic64_cmpxchg(v, old, new) (__cmpxchg_64(old, new, &(v)->counter))
#define atomic64_xchg(v, new) (__xchg_64(new, &(v)->counter))
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -253,7 +253,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
diff --git a/arch/h8300/include/asm/atomic.h b/arch/h8300/include/asm/atomic.h
index b641714..e6d1663 100644
--- a/arch/h8300/include/asm/atomic.h
+++ b/arch/h8300/include/asm/atomic.h
@@ -104,7 +104,7 @@ static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int ret;
unsigned long flags;
@@ -114,7 +114,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
if (ret != u)
v->counter += a;
local_irq_restore(flags);
- return ret != u;
+ return ret;
}
static __inline__ void atomic_clear_mask(unsigned long mask, unsigned long *v)
diff --git a/arch/ia64/include/asm/atomic.h b/arch/ia64/include/asm/atomic.h
index fdb8870..22aca21 100644
--- a/arch/ia64/include/asm/atomic.h
+++ b/arch/ia64/include/asm/atomic.h
@@ -90,7 +90,7 @@ ia64_atomic64_sub (__s64 i, atomic64_t *v)
(cmpxchg(&((v)->counter), old, new))
#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -102,7 +102,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
diff --git a/arch/m32r/include/asm/atomic.h b/arch/m32r/include/asm/atomic.h
index d64d894..c839426 100644
--- a/arch/m32r/include/asm/atomic.h
+++ b/arch/m32r/include/asm/atomic.h
@@ -239,15 +239,15 @@ static __inline__ int atomic_dec_return(atomic_t *v)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
- * atomic_add_unless - add unless the number is a given value
+ * __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -259,7 +259,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
diff --git a/arch/m68k/include/asm/atomic.h b/arch/m68k/include/asm/atomic.h
index 7dc8873..017a15e 100644
--- a/arch/m68k/include/asm/atomic.h
+++ b/arch/m68k/include/asm/atomic.h
@@ -183,7 +183,7 @@ static inline void atomic_set_mask(unsigned long mask, unsigned long *v)
__asm__ __volatile__("orl %1,%0" : "+m" (*v) : "id" (mask));
}
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -195,7 +195,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
index 833a402..31cb23d 100644
--- a/arch/mips/include/asm/atomic.h
+++ b/arch/mips/include/asm/atomic.h
@@ -303,15 +303,15 @@ static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
#define atomic_xchg(v, new) (xchg(&((v)->counter), (new)))
/**
- * atomic_add_unless - add unless the number is a given value
+ * __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -323,7 +323,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
#define atomic_dec_return(v) atomic_sub_return(1, (v))
@@ -679,7 +679,7 @@ static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v)
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
{
diff --git a/arch/mn10300/include/asm/atomic.h b/arch/mn10300/include/asm/atomic.h
index 041b9d6..a2e6759 100644
--- a/arch/mn10300/include/asm/atomic.h
+++ b/arch/mn10300/include/asm/atomic.h
@@ -260,13 +260,13 @@ static inline void atomic_dec(atomic_t *v)
#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
-#define atomic_add_unless(v, a, u) \
+#define __atomic_add_unless(v, a, u) \
({ \
int c, old; \
c = atomic_read(v); \
while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
c = old; \
- c != (u); \
+ c; \
})
diff --git a/arch/parisc/include/asm/atomic.h b/arch/parisc/include/asm/atomic.h
index 1924889..1914f17 100644
--- a/arch/parisc/include/asm/atomic.h
+++ b/arch/parisc/include/asm/atomic.h
@@ -197,15 +197,15 @@ static __inline__ int atomic_read(const atomic_t *v)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
- * atomic_add_unless - add unless the number is a given value
+ * __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -217,7 +217,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
@@ -316,7 +316,7 @@ atomic64_read(const atomic64_t *v)
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
{
diff --git a/arch/powerpc/include/asm/atomic.h b/arch/powerpc/include/asm/atomic.h
index b2bcbee..952e161 100644
--- a/arch/powerpc/include/asm/atomic.h
+++ b/arch/powerpc/include/asm/atomic.h
@@ -181,21 +181,21 @@ static __inline__ int atomic_dec_return(atomic_t *v)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
- * atomic_add_unless - add unless the number is a given value
+ * __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int t;
__asm__ __volatile__ (
PPC_RELEASE_BARRIER
-"1: lwarx %0,0,%1 # atomic_add_unless\n\
+"1: lwarx %0,0,%1 # __atomic_add_unless\n\
cmpw 0,%0,%3 \n\
beq- 2f \n\
add %0,%2,%0 \n"
@@ -209,7 +209,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
: "r" (&v->counter), "r" (a), "r" (u)
: "cc", "memory");
- return t != u;
+ return t;
}
@@ -443,7 +443,7 @@ static __inline__ long atomic64_dec_if_positive(atomic64_t *v)
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
{
@@ -451,7 +451,7 @@ static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
__asm__ __volatile__ (
PPC_RELEASE_BARRIER
-"1: ldarx %0,0,%1 # atomic_add_unless\n\
+"1: ldarx %0,0,%1 # __atomic_add_unless\n\
cmpd 0,%0,%3 \n\
beq- 2f \n\
add %0,%2,%0 \n"
diff --git a/arch/s390/include/asm/atomic.h b/arch/s390/include/asm/atomic.h
index 29d7563..7b0b0a7 100644
--- a/arch/s390/include/asm/atomic.h
+++ b/arch/s390/include/asm/atomic.h
@@ -93,7 +93,7 @@ static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
return old;
}
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -105,7 +105,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != u;
+ return c;
}
diff --git a/arch/sh/include/asm/atomic.h b/arch/sh/include/asm/atomic.h
index 8ddb263..2177596 100644
--- a/arch/sh/include/asm/atomic.h
+++ b/arch/sh/include/asm/atomic.h
@@ -38,15 +38,15 @@
#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
/**
- * atomic_add_unless - add unless the number is a given value
+ * __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -59,7 +59,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
c = old;
}
- return c != (u);
+ return c;
}
#define smp_mb__before_atomic_dec() smp_mb()
diff --git a/arch/sparc/include/asm/atomic_32.h b/arch/sparc/include/asm/atomic_32.h
index 7646f2c..bdce95e 100644
--- a/arch/sparc/include/asm/atomic_32.h
+++ b/arch/sparc/include/asm/atomic_32.h
@@ -22,7 +22,7 @@
extern int __atomic_add_return(int, atomic_t *);
extern int atomic_cmpxchg(atomic_t *, int, int);
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-extern int atomic_add_unless(atomic_t *, int, int);
+extern int __atomic_add_unless(atomic_t *, int, int);
extern void atomic_set(atomic_t *, int);
#define atomic_read(v) (*(volatile int *)&(v)->counter)
diff --git a/arch/sparc/include/asm/atomic_64.h b/arch/sparc/include/asm/atomic_64.h
index 337139e..1fc3d0a 100644
--- a/arch/sparc/include/asm/atomic_64.h
+++ b/arch/sparc/include/asm/atomic_64.h
@@ -70,7 +70,7 @@ extern long atomic64_sub_ret(long, atomic64_t *);
#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -82,7 +82,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
diff --git a/arch/tile/include/asm/atomic_32.h b/arch/tile/include/asm/atomic_32.h
index 246feed..c03349e 100644
--- a/arch/tile/include/asm/atomic_32.h
+++ b/arch/tile/include/asm/atomic_32.h
@@ -81,18 +81,18 @@ static inline int atomic_add_return(int i, atomic_t *v)
}
/**
- * atomic_add_unless - add unless the number is already a given value
+ * __atomic_add_unless - add unless the number is already a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as @v was not already @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
smp_mb(); /* barrier for proper semantics */
- return _atomic_xchg_add_unless(v, a, u) != u;
+ return _atomic_xchg_add_unless(v, a, u);
}
/**
@@ -199,7 +199,7 @@ static inline u64 atomic64_add_return(u64 i, atomic64_t *v)
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as @v was not already @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
static inline u64 atomic64_add_unless(atomic64_t *v, u64 a, u64 u)
{
diff --git a/arch/tile/include/asm/atomic_64.h b/arch/tile/include/asm/atomic_64.h
index a48dda3..27fe667 100644
--- a/arch/tile/include/asm/atomic_64.h
+++ b/arch/tile/include/asm/atomic_64.h
@@ -64,7 +64,7 @@ static inline int atomic_add_return(int i, atomic_t *v)
return val;
}
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int guess, oldval = v->counter;
do {
@@ -73,7 +73,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
guess = oldval;
oldval = atomic_cmpxchg(v, guess, guess + a);
} while (guess != oldval);
- return oldval != u;
+ return oldval;
}
/* Now the true 64-bit operations. */
diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h
index 897969b..5fe9cb3 100644
--- a/arch/x86/include/asm/atomic.h
+++ b/arch/x86/include/asm/atomic.h
@@ -221,15 +221,15 @@ static inline int atomic_xchg(atomic_t *v, int new)
}
/**
- * atomic_add_unless - add unless the number is already a given value
+ * __atomic_add_unless - add unless the number is already a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as @v was not already @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -241,7 +241,7 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h
index 2a934aa..24098aa 100644
--- a/arch/x86/include/asm/atomic64_32.h
+++ b/arch/x86/include/asm/atomic64_32.h
@@ -263,7 +263,7 @@ static inline int atomic64_add_negative(long long i, atomic64_t *v)
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
{
diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h
index 49fd1ea..017594d 100644
--- a/arch/x86/include/asm/atomic64_64.h
+++ b/arch/x86/include/asm/atomic64_64.h
@@ -202,7 +202,7 @@ static inline long atomic64_xchg(atomic64_t *v, long new)
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
static inline int atomic64_add_unless(atomic64_t *v, long a, long u)
{
diff --git a/arch/xtensa/include/asm/atomic.h b/arch/xtensa/include/asm/atomic.h
index 7cca2fb..e464212 100644
--- a/arch/xtensa/include/asm/atomic.h
+++ b/arch/xtensa/include/asm/atomic.h
@@ -225,15 +225,15 @@ static inline int atomic_sub_return(int i, atomic_t * v)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
- * atomic_add_unless - add unless the number is a given value
+ * __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
- * Returns non-zero if @v was not @u, and zero otherwise.
+ * Returns the old value of @v.
*/
-static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
@@ -245,7 +245,7 @@ static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
break;
c = old;
}
- return c != (u);
+ return c;
}
diff --git a/include/linux/atomic.h b/include/linux/atomic.h
index ed0eb23..fc31190 100644
--- a/include/linux/atomic.h
+++ b/include/linux/atomic.h
@@ -3,6 +3,20 @@
#include <asm/atomic.h>
/**
+ * atomic_add_unless - add unless the number is already a given value
+ * @v: pointer of type atomic_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as @v was not already @u.
+ * Returns non-zero if @v was not @u, and zero otherwise.
+ */
+static inline int atomic_add_unless(atomic_t *v, int a, int u)
+{
+ return __atomic_add_unless(v, a, u) != u;
+}
+
+/**
* atomic_inc_not_zero - increment unless the number is zero
* @v: pointer of type atomic_t
*
--
1.7.4
next prev parent reply other threads:[~2011-05-31 19:11 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-31 19:10 [PATCH 1/2] atomic: use <linux/atomic.h> Arun Sharma
2011-05-31 19:10 ` Arun Sharma [this message]
2011-05-31 20:21 ` [PATCH 2/2] atomic: move atomic_add_unless to generic code Mike Frysinger
2011-05-31 21:17 ` Arun Sharma
2011-06-02 14:53 ` Mike Frysinger
2011-06-02 17:23 ` Arun Sharma
2011-06-07 23:48 ` Andrew Morton
2011-06-08 0:42 ` Arun Sharma
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