From 0e03bb6d6495ac91b0ccf9263ab162352570e290 Mon Sep 17 00:00:00 2001
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 18 Jun 2008 21:03:26 -0700
Subject: [PATCH] --- yaml --- r: 99352 b: refs/heads/master c:
 1a750e0cd7a30c478723ecfa1df685efcdd38a90 h: refs/heads/master v: v3

---
 [refs]                         |  2 +-
 trunk/include/asm-x86/bitops.h | 28 +++++++++++++++++++++++-----
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/[refs] b/[refs]
index fbfb0f7bbce4..39802ea86684 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 5136dea5734cfddbc6d7ccb7ead85a3ac7ce3de2
+refs/heads/master: 1a750e0cd7a30c478723ecfa1df685efcdd38a90
diff --git a/trunk/include/asm-x86/bitops.h b/trunk/include/asm-x86/bitops.h
index 7d2494bdc660..ab7635a4acd9 100644
--- a/trunk/include/asm-x86/bitops.h
+++ b/trunk/include/asm-x86/bitops.h
@@ -23,11 +23,22 @@
 #if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 1)
 /* Technically wrong, but this avoids compilation errors on some gcc
    versions. */
-#define ADDR "=m" (*(volatile long *) addr)
+#define BITOP_ADDR(x) "=m" (*(volatile long *) (x))
 #else
-#define ADDR "+m" (*(volatile long *) addr)
+#define BITOP_ADDR(x) "+m" (*(volatile long *) (x))
 #endif
 
+#define ADDR BITOP_ADDR(addr)
+
+/*
+ * We do the locked ops that don't return the old value as
+ * a mask operation on a byte.
+ */
+#define IS_IMMEDIATE(nr) \
+	(__builtin_constant_p(nr))
+#define CONST_MASK_ADDR BITOP_ADDR(addr + (nr>>3))
+#define CONST_MASK (1 << (nr & 7))
+
 /**
  * set_bit - Atomically set a bit in memory
  * @nr: the bit to set
@@ -43,11 +54,15 @@
  * Note that @nr may be almost arbitrarily large; this function is not
  * restricted to acting on a single-word quantity.
  */
-static inline void set_bit(int nr, volatile unsigned long *addr)
+static inline void set_bit(unsigned int nr, volatile unsigned long *addr)
 {
-	asm volatile(LOCK_PREFIX "bts %1,%0" : ADDR : "Ir" (nr) : "memory");
+	if (IS_IMMEDIATE(nr))
+		asm volatile(LOCK_PREFIX "orb %1,%0" : CONST_MASK_ADDR : "i" (CONST_MASK) : "memory");
+	else
+		asm volatile(LOCK_PREFIX "bts %1,%0" : ADDR : "Ir" (nr) : "memory");
 }
 
+
 /**
  * __set_bit - Set a bit in memory
  * @nr: the bit to set
@@ -74,7 +89,10 @@ static inline void __set_bit(int nr, volatile unsigned long *addr)
  */
 static inline void clear_bit(int nr, volatile unsigned long *addr)
 {
-	asm volatile(LOCK_PREFIX "btr %1,%0" : ADDR : "Ir" (nr));
+	if (IS_IMMEDIATE(nr))
+		asm volatile(LOCK_PREFIX "andb %1,%0" : CONST_MASK_ADDR : "i" (~CONST_MASK));
+	else
+		asm volatile(LOCK_PREFIX "btr %1,%0" : ADDR : "Ir" (nr));
 }
 
 /*