X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;ds=sidebyside;f=include%2Flinux%2Flog2.h;h=57e641e19a8106122783073291cf53adfc36acd0;hb=3d67f2d7c0fb28b0eb6a6aa100b190526a971ad9;hp=d02e1a547a7e9deb1e8bc21857780bdc2c7693c0;hpb=f0eef25339f92f7cd4aeea23d9ae97987a5a1e82;p=powerpc.git

diff --git a/include/linux/log2.h b/include/linux/log2.h
index d02e1a547a..57e641e19a 100644
--- a/include/linux/log2.h
+++ b/include/linux/log2.h
@@ -43,6 +43,17 @@ int __ilog2_u64(u64 n)
 }
 #endif
 
+/*
+ *  Determine whether some value is a power of two, where zero is
+ * *not* considered a power of two.
+ */
+
+static inline __attribute__((const))
+bool is_power_of_2(unsigned long n)
+{
+	return (n != 0 && ((n & (n - 1)) == 0));
+}
+
 /*
  * round up to nearest power of two
  */
@@ -141,7 +152,7 @@ unsigned long __roundup_pow_of_two(unsigned long n)
  * roundup_pow_of_two - round the given value up to nearest power of two
  * @n - parameter
  *
- * round the given balue up to the nearest power of two
+ * round the given value up to the nearest power of two
  * - the result is undefined when n == 0
  * - this can be used to initialise global variables from constant data
  */