From f38c76b29a7b33079f2edc008dcc54d8bed591a6 Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@mit.edu>
Date: Wed, 25 Jun 2014 22:15:29 -0400
Subject: [PATCH] add patch replace-builtin_log-with-ilog2

---
 replace-builtin_log-with-ilog2 | 40 ++++++++++++++++++++++++++++++++++++++++
 series                         |  1 +
 2 files changed, 41 insertions(+)
 create mode 100644 replace-builtin_log-with-ilog2

diff --git a/replace-builtin_log-with-ilog2 b/replace-builtin_log-with-ilog2
new file mode 100644
index 00000000..b855ee15
--- /dev/null
+++ b/replace-builtin_log-with-ilog2
@@ -0,0 +1,40 @@
+fs/mbcache: replace __builtin_log2() with ilog2()
+
+From: T Makphaibulchoke <tmac@hp.com>
+
+Fix compiler error with some gcc version(s) that do not
+support __builtin_log2() by replacing __builtin_log2() with
+ilog2().
+
+Signed-off-by: T. Makphaibulchoke <tmac@hp.com>
+Signed-off-by: Theodore Ts'o <tytso@mit.edu>
+Reviewed-by: Maciej W. Rozycki <macro@linux-mips.org>
+---
+ fs/mbcache.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/fs/mbcache.c b/fs/mbcache.c
+index bf166e3..187477d 100644
+--- a/fs/mbcache.c
++++ b/fs/mbcache.c
+@@ -73,6 +73,7 @@
+ #include <linux/mbcache.h>
+ #include <linux/init.h>
+ #include <linux/blockgroup_lock.h>
++#include <linux/log2.h>
+ 
+ #ifdef MB_CACHE_DEBUG
+ # define mb_debug(f...) do { \
+@@ -93,7 +94,7 @@
+ 
+ #define MB_CACHE_WRITER ((unsigned short)~0U >> 1)
+ 
+-#define MB_CACHE_ENTRY_LOCK_BITS	__builtin_log2(NR_BG_LOCKS)
++#define MB_CACHE_ENTRY_LOCK_BITS	ilog2(NR_BG_LOCKS)
+ #define	MB_CACHE_ENTRY_LOCK_INDEX(ce)			\
+ 	(hash_long((unsigned long)ce, MB_CACHE_ENTRY_LOCK_BITS))
+ 
+-- 
+1.7.11.3
+
+
diff --git a/series b/series
index 3ffb0fb7..fc529450 100644
--- a/series
+++ b/series
@@ -1,6 +1,7 @@
 # BASE f8409abdc592e
 
 fix-buffer-double-free-in-ext4_alloc_branch
+replace-builtin_log-with-ilog2
 fix-32bit-breakage-in-block-device
 remove-metadata-reservation-checks
 
-- 
2.11.4.GIT