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authorMarcel Ziswiler <marcel.ziswiler@toradex.com>2017-06-17 17:01:11 +0200
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2017-06-17 17:01:11 +0200
commitc1d5fe2d54551b95b812143d94d8168da2220dd8 (patch)
treefdde4472ab2b19fcadaae22d68a0c9b008f74373 /include/linux/log2.h
parent0068a1b36d309f22698f7de7478b72e672360129 (diff)
parent1bd30958ec55d80ca72d2ca4e7e5c3d9fbf3173e (diff)
Merge tag 'v4.4.73' into toradex_vf_4.4-nextColibri-VF_LXDE-Image_2.7b3-20170630
This is the 4.4.73 stable release
Diffstat (limited to 'include/linux/log2.h')
-rw-r--r--include/linux/log2.h13
1 files changed, 12 insertions, 1 deletions
diff --git a/include/linux/log2.h b/include/linux/log2.h
index f38fae23bdac..c373295f359f 100644
--- a/include/linux/log2.h
+++ b/include/linux/log2.h
@@ -194,6 +194,17 @@ unsigned long __rounddown_pow_of_two(unsigned long n)
* ... and so on.
*/
-#define order_base_2(n) ilog2(roundup_pow_of_two(n))
+static inline __attribute_const__
+int __order_base_2(unsigned long n)
+{
+ return n > 1 ? ilog2(n - 1) + 1 : 0;
+}
+#define order_base_2(n) \
+( \
+ __builtin_constant_p(n) ? ( \
+ ((n) == 0 || (n) == 1) ? 0 : \
+ ilog2((n) - 1) + 1) : \
+ __order_base_2(n) \
+)
#endif /* _LINUX_LOG2_H */