From d5c844f18d1dd811877d4837ad306f4839483158 Mon Sep 17 00:00:00 2001
From: Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
Date: Sat, 22 Oct 2016 20:44:18 -0400
Subject: [PATCH] added LOG2_CEIL

---
 include/villas/utils.h | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/include/villas/utils.h b/include/villas/utils.h
index 87f2a6c69..4207d3626 100644
--- a/include/villas/utils.h
+++ b/include/villas/utils.h
@@ -55,7 +55,11 @@
 #define ALIGN_MASK(x, m) (((uintptr_t) (x) + (m)) & ~(m))
 #define IS_ALIGNED(x, a) (ALIGN(x, a) == (uintptr_t) x)
 
-#define CEIL(x, y)	((x + y - 1) / y)
+/** Round-up integer division */
+#define CEIL(x, y)	(((x) + (y) - 1) / (y))
+
+/** Get nearest up-rounded power of 2 */
+#define LOG2_CEIL(x)	(1 << log2i((x) - 1) + 1)
 
 /** Calculate the number of elements in an array. */
 #define ARRAY_LEN(a)	( sizeof (a) / sizeof (a)[0] )
@@ -212,6 +216,13 @@ __attribute__((always_inline)) static inline uint64_t rdtsc()
 	return tsc;
 }
 
+/** Get log2 of long long integers */
+static inline int log2i(long long x) {
+	assert(x > 0);
+
+	return sizeof(x) * 8 - __builtin_clzll(x) - 1;
+}
+
 /** Sleep with rdtsc */
 void rdtsc_sleep(uint64_t nanosecs, uint64_t start);