From 67487d33467ea353e1e7f13319890685bef4e54f Mon Sep 17 00:00:00 2001
From: Marcin Slusarz <marcin.slusarz@gmail.com>
Date: Sun, 26 Jun 2011 21:39:18 +0200
Subject: [PATCH] --- yaml --- r: 255045 b: refs/heads/master c:
 c4089f98e943ff445665dea49c190657b34ccffe h: refs/heads/master i:   255043:
 e9aacd1b05e72711d6fbb401737a4afc360a506a v: v3

---
 [refs]          |  2 +-
 trunk/mm/slub.c | 36 ++++++++++++++++++++++++++++++++++--
 2 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 42046ec3a981..1c9bc696dedc 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d18a90dd85f8243ed20cdadb6d8a37d595df456d
+refs/heads/master: c4089f98e943ff445665dea49c190657b34ccffe
diff --git a/trunk/mm/slub.c b/trunk/mm/slub.c
index 0e4f4f8245bc..e3403b30159e 100644
--- a/trunk/mm/slub.c
+++ b/trunk/mm/slub.c
@@ -589,10 +589,10 @@ static void init_object(struct kmem_cache *s, void *object, u8 val)
 		memset(p + s->objsize, val, s->inuse - s->objsize);
 }
 
-static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
+static u8 *check_bytes8(u8 *start, u8 value, unsigned int bytes)
 {
 	while (bytes) {
-		if (*start != (u8)value)
+		if (*start != value)
 			return start;
 		start++;
 		bytes--;
@@ -600,6 +600,38 @@ static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
 	return NULL;
 }
 
+static u8 *check_bytes(u8 *start, u8 value, unsigned int bytes)
+{
+	u64 value64;
+	unsigned int words, prefix;
+
+	if (bytes <= 16)
+		return check_bytes8(start, value, bytes);
+
+	value64 = value | value << 8 | value << 16 | value << 24;
+	value64 = value64 | value64 << 32;
+	prefix = 8 - ((unsigned long)start) % 8;
+
+	if (prefix) {
+		u8 *r = check_bytes8(start, value, prefix);
+		if (r)
+			return r;
+		start += prefix;
+		bytes -= prefix;
+	}
+
+	words = bytes / 8;
+
+	while (words) {
+		if (*(u64 *)start != value64)
+			return check_bytes8(start, value, 8);
+		start += 8;
+		words--;
+	}
+
+	return check_bytes8(start, value, bytes % 8);
+}
+
 static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
 						void *from, void *to)
 {