X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-i386%2Flocal.h;h=12060e22f7e2a53204f4f8cfec20f95abfa6eeda;hb=refs%2Fheads%2Fvserver;hp=0177da80dde34f68b98dee1a533493b780c8d62f;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git

diff --git a/include/asm-i386/local.h b/include/asm-i386/local.h
index 0177da80d..12060e22f 100644
--- a/include/asm-i386/local.h
+++ b/include/asm-i386/local.h
@@ -5,7 +5,7 @@
 
 typedef struct
 {
-	volatile unsigned long counter;
+	volatile long counter;
 } local_t;
 
 #define LOCAL_INIT(i)	{ (i) }
@@ -17,32 +17,30 @@ static __inline__ void local_inc(local_t *v)
 {
 	__asm__ __volatile__(
 		"incl %0"
-		:"=m" (v->counter)
-		:"m" (v->counter));
+		:"+m" (v->counter));
 }
 
 static __inline__ void local_dec(local_t *v)
 {
 	__asm__ __volatile__(
 		"decl %0"
-		:"=m" (v->counter)
-		:"m" (v->counter));
+		:"+m" (v->counter));
 }
 
-static __inline__ void local_add(unsigned long i, local_t *v)
+static __inline__ void local_add(long i, local_t *v)
 {
 	__asm__ __volatile__(
 		"addl %1,%0"
-		:"=m" (v->counter)
-		:"ir" (i), "m" (v->counter));
+		:"+m" (v->counter)
+		:"ir" (i));
 }
 
-static __inline__ void local_sub(unsigned long i, local_t *v)
+static __inline__ void local_sub(long i, local_t *v)
 {
 	__asm__ __volatile__(
 		"subl %1,%0"
-		:"=m" (v->counter)
-		:"ir" (i), "m" (v->counter));
+		:"+m" (v->counter)
+		:"ir" (i));
 }
 
 /* On x86, these are no better than the atomic variants. */
@@ -55,12 +53,26 @@ static __inline__ void local_sub(unsigned long i, local_t *v)
  * much more efficient than these naive implementations.  Note they take
  * a variable, not an address.
  */
-#define cpu_local_read(v)	local_read(&__get_cpu_var(v))
-#define cpu_local_set(v, i)	local_set(&__get_cpu_var(v), (i))
-#define cpu_local_inc(v)	local_inc(&__get_cpu_var(v))
-#define cpu_local_dec(v)	local_dec(&__get_cpu_var(v))
-#define cpu_local_add(i, v)	local_add((i), &__get_cpu_var(v))
-#define cpu_local_sub(i, v)	local_sub((i), &__get_cpu_var(v))
+
+/* Need to disable preemption for the cpu local counters otherwise we could
+   still access a variable of a previous CPU in a non atomic way. */
+#define cpu_local_wrap_v(v)	 	\
+	({ local_t res__;		\
+	   preempt_disable(); 		\
+	   res__ = (v);			\
+	   preempt_enable();		\
+	   res__; })
+#define cpu_local_wrap(v)		\
+	({ preempt_disable();		\
+	   v;				\
+	   preempt_enable(); })		\
+
+#define cpu_local_read(v)    cpu_local_wrap_v(local_read(&__get_cpu_var(v)))
+#define cpu_local_set(v, i)  cpu_local_wrap(local_set(&__get_cpu_var(v), (i)))
+#define cpu_local_inc(v)     cpu_local_wrap(local_inc(&__get_cpu_var(v)))
+#define cpu_local_dec(v)     cpu_local_wrap(local_dec(&__get_cpu_var(v)))
+#define cpu_local_add(i, v)  cpu_local_wrap(local_add((i), &__get_cpu_var(v)))
+#define cpu_local_sub(i, v)  cpu_local_wrap(local_sub((i), &__get_cpu_var(v)))
 
 #define __cpu_local_inc(v)	cpu_local_inc(v)
 #define __cpu_local_dec(v)	cpu_local_dec(v)