1 files changed, 22 insertions, 0 deletions

diff --git a/include/asm-generic/cmpxchg.h b/include/asm-generic/cmpxchg.h
new file mode 100644
index 000000000000..213ac6e8fe39
--- /dev/null
+++ b/include/asm-generic/cmpxchg.h
@@ -0,0 +1,22 @@
+#ifndef __ASM_GENERIC_CMPXCHG_H
+#define __ASM_GENERIC_CMPXCHG_H
+
+/*
+ * Generic cmpxchg
+ *
+ * Uses the local cmpxchg. Does not support SMP.
+ */
+#ifdef CONFIG_SMP
+#error "Cannot use generic cmpxchg on SMP"
+#endif
+
+/*
+ * Atomic compare and exchange.
+ *
+ * Do not define __HAVE_ARCH_CMPXCHG because we want to use it to check whether
+ * a cmpxchg primitive faster than repeated local irq save/restore exists.
+ */
+#define cmpxchg(ptr, o, n)      cmpxchg_local((ptr), (o), (n))
+#define cmpxchg64(ptr, o, n)    cmpxchg64_local((ptr), (o), (n))
+
+#endif