x86, asm: Introduce and use percpu_inc()
... generating slightly smaller code.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <4BCF261F020000780003B33C@vpn.id2.novell.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
index 66a272d..0ec6d12 100644
--- a/arch/x86/include/asm/percpu.h
+++ b/arch/x86/include/asm/percpu.h
@@ -190,6 +190,29 @@
pfo_ret__; \
})
+#define percpu_unary_op(op, var) \
+({ \
+ switch (sizeof(var)) { \
+ case 1: \
+ asm(op "b "__percpu_arg(0) \
+ : "+m" (var)); \
+ break; \
+ case 2: \
+ asm(op "w "__percpu_arg(0) \
+ : "+m" (var)); \
+ break; \
+ case 4: \
+ asm(op "l "__percpu_arg(0) \
+ : "+m" (var)); \
+ break; \
+ case 8: \
+ asm(op "q "__percpu_arg(0) \
+ : "+m" (var)); \
+ break; \
+ default: __bad_percpu_size(); \
+ } \
+})
+
/*
* percpu_read() makes gcc load the percpu variable every time it is
* accessed while percpu_read_stable() allows the value to be cached.
@@ -207,6 +230,7 @@
#define percpu_and(var, val) percpu_to_op("and", var, val)
#define percpu_or(var, val) percpu_to_op("or", var, val)
#define percpu_xor(var, val) percpu_to_op("xor", var, val)
+#define percpu_inc(var) percpu_unary_op("inc", var)
#define __this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
#define __this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))