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Diffstat (limited to 'include/asm-x86_64/local.h')
-rw-r--r--include/asm-x86_64/local.h73
1 files changed, 73 insertions, 0 deletions
diff --git a/include/asm-x86_64/local.h b/include/asm-x86_64/local.h
new file mode 100644
index 000000000000..169c223a8452
--- /dev/null
+++ b/include/asm-x86_64/local.h
@@ -0,0 +1,73 @@
+#ifndef _ARCH_X8664_LOCAL_H
+#define _ARCH_X8664_LOCAL_H
+
+#include <linux/percpu.h>
+
+typedef struct
+{
+ volatile unsigned int counter;
+} local_t;
+
+#define LOCAL_INIT(i) { (i) }
+
+#define local_read(v) ((v)->counter)
+#define local_set(v,i) (((v)->counter) = (i))
+
+static __inline__ void local_inc(local_t *v)
+{
+ __asm__ __volatile__(
+ "incl %0"
+ :"=m" (v->counter)
+ :"m" (v->counter));
+}
+
+static __inline__ void local_dec(local_t *v)
+{
+ __asm__ __volatile__(
+ "decl %0"
+ :"=m" (v->counter)
+ :"m" (v->counter));
+}
+
+static __inline__ void local_add(unsigned long i, local_t *v)
+{
+ __asm__ __volatile__(
+ "addl %1,%0"
+ :"=m" (v->counter)
+ :"ir" (i), "m" (v->counter));
+}
+
+static __inline__ void local_sub(unsigned long i, local_t *v)
+{
+ __asm__ __volatile__(
+ "subl %1,%0"
+ :"=m" (v->counter)
+ :"ir" (i), "m" (v->counter));
+}
+
+/* On x86, these are no better than the atomic variants. */
+#define __local_inc(l) local_inc(l)
+#define __local_dec(l) local_dec(l)
+#define __local_add(i,l) local_add((i),(l))
+#define __local_sub(i,l) local_sub((i),(l))
+
+/* Use these for per-cpu local_t variables: on some archs they are
+ * much more efficient than these naive implementations. Note they take
+ * a variable, not an address.
+ *
+ * This could be done better if we moved the per cpu data directly
+ * after GS.
+ */
+#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))
+
+#define __cpu_local_inc(v) cpu_local_inc(v)
+#define __cpu_local_dec(v) cpu_local_dec(v)
+#define __cpu_local_add(i, v) cpu_local_add((i), (v))
+#define __cpu_local_sub(i, v) cpu_local_sub((i), (v))
+
+#endif /* _ARCH_I386_LOCAL_H */