atomic_t: Cast to volatile when accessing atomic variables
In preparation for removing volatile from the atomic_t definition, this
patch adds a volatile cast to all the atomic read functions.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/alpha/include/asm/atomic.h b/arch/alpha/include/asm/atomic.h
index 610dff4..e756d04 100644
--- a/arch/alpha/include/asm/atomic.h
+++ b/arch/alpha/include/asm/atomic.h
@@ -17,8 +17,8 @@
#define ATOMIC_INIT(i) ( (atomic_t) { (i) } )
#define ATOMIC64_INIT(i) ( (atomic64_t) { (i) } )
-#define atomic_read(v) ((v)->counter + 0)
-#define atomic64_read(v) ((v)->counter + 0)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
+#define atomic64_read(v) (*(volatile long *)&(v)->counter)
#define atomic_set(v,i) ((v)->counter = (i))
#define atomic64_set(v,i) ((v)->counter = (i))
diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h
index e8ddec2..a0162fa 100644
--- a/arch/arm/include/asm/atomic.h
+++ b/arch/arm/include/asm/atomic.h
@@ -24,7 +24,7 @@
* strex/ldrex monitor on some implementations. The reason we can use it for
* atomic_set() is the clrex or dummy strex done on every exception return.
*/
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v,i) (((v)->counter) = (i))
#if __LINUX_ARM_ARCH__ >= 6
diff --git a/arch/avr32/include/asm/atomic.h b/arch/avr32/include/asm/atomic.h
index b131c27..bbce6a1 100644
--- a/arch/avr32/include/asm/atomic.h
+++ b/arch/avr32/include/asm/atomic.h
@@ -19,7 +19,7 @@
#define ATOMIC_INIT(i) { (i) }
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v, i) (((v)->counter) = i)
/*
diff --git a/arch/cris/include/asm/atomic.h b/arch/cris/include/asm/atomic.h
index a6aca81..88dc9b9 100644
--- a/arch/cris/include/asm/atomic.h
+++ b/arch/cris/include/asm/atomic.h
@@ -15,7 +15,7 @@
#define ATOMIC_INIT(i) { (i) }
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v,i) (((v)->counter) = (i))
/* These should be written in asm but we do it in C for now. */
diff --git a/arch/frv/include/asm/atomic.h b/arch/frv/include/asm/atomic.h
index 00a57af..fae32c7 100644
--- a/arch/frv/include/asm/atomic.h
+++ b/arch/frv/include/asm/atomic.h
@@ -36,7 +36,7 @@
#define smp_mb__after_atomic_inc() barrier()
#define ATOMIC_INIT(i) { (i) }
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v, i) (((v)->counter) = (i))
#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
diff --git a/arch/h8300/include/asm/atomic.h b/arch/h8300/include/asm/atomic.h
index 33c8c0f..e936804 100644
--- a/arch/h8300/include/asm/atomic.h
+++ b/arch/h8300/include/asm/atomic.h
@@ -10,7 +10,7 @@
#define ATOMIC_INIT(i) { (i) }
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v, i) (((v)->counter) = i)
#include <asm/system.h>
diff --git a/arch/ia64/include/asm/atomic.h b/arch/ia64/include/asm/atomic.h
index 88405cb..4e19484 100644
--- a/arch/ia64/include/asm/atomic.h
+++ b/arch/ia64/include/asm/atomic.h
@@ -21,8 +21,8 @@
#define ATOMIC_INIT(i) ((atomic_t) { (i) })
#define ATOMIC64_INIT(i) ((atomic64_t) { (i) })
-#define atomic_read(v) ((v)->counter)
-#define atomic64_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
+#define atomic64_read(v) (*(volatile long *)&(v)->counter)
#define atomic_set(v,i) (((v)->counter) = (i))
#define atomic64_set(v,i) (((v)->counter) = (i))
diff --git a/arch/m32r/include/asm/atomic.h b/arch/m32r/include/asm/atomic.h
index 63f0cf0..d44a51e 100644
--- a/arch/m32r/include/asm/atomic.h
+++ b/arch/m32r/include/asm/atomic.h
@@ -26,7 +26,7 @@
*
* Atomically reads the value of @v.
*/
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
/**
* atomic_set - set atomic variable
diff --git a/arch/m68k/include/asm/atomic_mm.h b/arch/m68k/include/asm/atomic_mm.h
index d9d2ed6..6a223b3 100644
--- a/arch/m68k/include/asm/atomic_mm.h
+++ b/arch/m68k/include/asm/atomic_mm.h
@@ -15,7 +15,7 @@
#define ATOMIC_INIT(i) { (i) }
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v, i) (((v)->counter) = i)
static inline void atomic_add(int i, atomic_t *v)
diff --git a/arch/m68k/include/asm/atomic_no.h b/arch/m68k/include/asm/atomic_no.h
index 5674cb9..289310c 100644
--- a/arch/m68k/include/asm/atomic_no.h
+++ b/arch/m68k/include/asm/atomic_no.h
@@ -15,7 +15,7 @@
#define ATOMIC_INIT(i) { (i) }
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v, i) (((v)->counter) = i)
static __inline__ void atomic_add(int i, atomic_t *v)
diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
index 519197e..59dc0c7 100644
--- a/arch/mips/include/asm/atomic.h
+++ b/arch/mips/include/asm/atomic.h
@@ -29,7 +29,7 @@
*
* Atomically reads the value of @v.
*/
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
/*
* atomic_set - set atomic variable
@@ -410,7 +410,7 @@
* @v: pointer of type atomic64_t
*
*/
-#define atomic64_read(v) ((v)->counter)
+#define atomic64_read(v) (*(volatile long *)&(v)->counter)
/*
* atomic64_set - set atomic variable
diff --git a/arch/mn10300/include/asm/atomic.h b/arch/mn10300/include/asm/atomic.h
index 5bf5be9..e41222d 100644
--- a/arch/mn10300/include/asm/atomic.h
+++ b/arch/mn10300/include/asm/atomic.h
@@ -31,7 +31,7 @@
* Atomically reads the value of @v. Note that the guaranteed
* useful range of an atomic_t is only 24 bits.
*/
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
/**
* atomic_set - set atomic variable
diff --git a/arch/parisc/include/asm/atomic.h b/arch/parisc/include/asm/atomic.h
index 716634d..f819559 100644
--- a/arch/parisc/include/asm/atomic.h
+++ b/arch/parisc/include/asm/atomic.h
@@ -189,7 +189,7 @@
static __inline__ int atomic_read(const atomic_t *v)
{
- return v->counter;
+ return (*(volatile int *)&(v)->counter);
}
/* exported interface */
@@ -286,7 +286,7 @@
static __inline__ s64
atomic64_read(const atomic64_t *v)
{
- return v->counter;
+ return (*(volatile long *)&(v)->counter);
}
#define atomic64_add(i,v) ((void)(__atomic64_add_return( ((s64)(i)),(v))))
diff --git a/arch/sh/include/asm/atomic.h b/arch/sh/include/asm/atomic.h
index 275a448..c798312 100644
--- a/arch/sh/include/asm/atomic.h
+++ b/arch/sh/include/asm/atomic.h
@@ -13,7 +13,7 @@
#define ATOMIC_INIT(i) ( (atomic_t) { (i) } )
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v,i) ((v)->counter = (i))
#if defined(CONFIG_GUSA_RB)
diff --git a/arch/sparc/include/asm/atomic_32.h b/arch/sparc/include/asm/atomic_32.h
index f0d343c..7ae128b 100644
--- a/arch/sparc/include/asm/atomic_32.h
+++ b/arch/sparc/include/asm/atomic_32.h
@@ -25,7 +25,7 @@
extern int atomic_add_unless(atomic_t *, int, int);
extern void atomic_set(atomic_t *, int);
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_add(i, v) ((void)__atomic_add_return( (int)(i), (v)))
#define atomic_sub(i, v) ((void)__atomic_add_return(-(int)(i), (v)))
diff --git a/arch/sparc/include/asm/atomic_64.h b/arch/sparc/include/asm/atomic_64.h
index f2e4800..2050ca0 100644
--- a/arch/sparc/include/asm/atomic_64.h
+++ b/arch/sparc/include/asm/atomic_64.h
@@ -13,8 +13,8 @@
#define ATOMIC_INIT(i) { (i) }
#define ATOMIC64_INIT(i) { (i) }
-#define atomic_read(v) ((v)->counter)
-#define atomic64_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
+#define atomic64_read(v) (*(volatile long *)&(v)->counter)
#define atomic_set(v, i) (((v)->counter) = i)
#define atomic64_set(v, i) (((v)->counter) = i)
diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h
index 8f8217b..37b39d2 100644
--- a/arch/x86/include/asm/atomic.h
+++ b/arch/x86/include/asm/atomic.h
@@ -22,7 +22,7 @@
*/
static inline int atomic_read(const atomic_t *v)
{
- return v->counter;
+ return (*(volatile int *)&(v)->counter);
}
/**
diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h
index 51c5b40..b014e23 100644
--- a/arch/x86/include/asm/atomic64_64.h
+++ b/arch/x86/include/asm/atomic64_64.h
@@ -18,7 +18,7 @@
*/
static inline long atomic64_read(const atomic64_t *v)
{
- return v->counter;
+ return (*(volatile long *)&(v)->counter);
}
/**
diff --git a/arch/xtensa/include/asm/atomic.h b/arch/xtensa/include/asm/atomic.h
index 22d6dde..a96a061 100644
--- a/arch/xtensa/include/asm/atomic.h
+++ b/arch/xtensa/include/asm/atomic.h
@@ -46,7 +46,7 @@
*
* Atomically reads the value of @v.
*/
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
/**
* atomic_set - set atomic variable
diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
index c99c64d..c33749f 100644
--- a/include/asm-generic/atomic.h
+++ b/include/asm-generic/atomic.h
@@ -33,7 +33,7 @@
* Atomically reads the value of @v. Note that the guaranteed
* useful range of an atomic_t is only 24 bits.
*/
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
/**
* atomic_set - set atomic variable