Index: uspace/app/hbench/Makefile
===================================================================
--- uspace/app/hbench/Makefile	(revision d17cf8c8d11e7ff1d0ec369af3ba9a1d6addc90c)
+++ uspace/app/hbench/Makefile	(revision 94d52d53a4608577d762072e1163d6e80af5bb39)
@@ -38,4 +38,5 @@
 	env.c \
 	main.c \
+	utils.c \
 	fs/dirread.c \
 	fs/fileread.c \
Index: uspace/app/hbench/hbench.h
===================================================================
--- uspace/app/hbench/hbench.h	(revision d17cf8c8d11e7ff1d0ec369af3ba9a1d6addc90c)
+++ uspace/app/hbench/hbench.h	(revision 94d52d53a4608577d762072e1163d6e80af5bb39)
@@ -39,7 +39,5 @@
 #include <adt/hash_table.h>
 #include <errno.h>
-#include <stdarg.h>
 #include <stdbool.h>
-#include <stdio.h>
 #include <perf.h>
 
@@ -79,11 +77,6 @@
 } benchmark_t;
 
-static inline void bench_run_init(bench_run_t *run, char *error_buffer,
-    size_t error_buffer_size)
-{
-	stopwatch_init(&run->stopwatch);
-	run->error_buffer = error_buffer;
-	run->error_buffer_size = error_buffer_size;
-}
+extern void bench_run_init(bench_run_t *, char *, size_t);
+extern bool bench_run_fail(bench_run_t *, const char *, ...);
 
 static inline void bench_run_start(bench_run_t *run)
@@ -95,14 +88,4 @@
 {
 	stopwatch_stop(&run->stopwatch);
-}
-
-static inline bool bench_run_fail(bench_run_t *run, const char *fmt, ...)
-{
-	va_list args;
-	va_start(args, fmt);
-	vsnprintf(run->error_buffer, run->error_buffer_size, fmt, args);
-	va_end(args);
-
-	return false;
 }
 
Index: uspace/app/hbench/utils.c
===================================================================
--- uspace/app/hbench/utils.c	(revision 94d52d53a4608577d762072e1163d6e80af5bb39)
+++ uspace/app/hbench/utils.c	(revision 94d52d53a4608577d762072e1163d6e80af5bb39)
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2019 Vojtech Horky
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup hbench
+ * @{
+ */
+/**
+ * @file
+ */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include "hbench.h"
+
+/** Initialize bench run structure.
+ *
+ * @param run Structure to intialize.
+ * @param error_buffer Pre-allocated memory to use for error messages.
+ * @param error_buffer_size Size of error_buffer.
+ */
+void bench_run_init(bench_run_t *run, char *error_buffer, size_t error_buffer_size)
+{
+	stopwatch_init(&run->stopwatch);
+	run->error_buffer = error_buffer;
+	run->error_buffer_size = error_buffer_size;
+}
+
+/** Format error message on benchmark failure.
+ *
+ * This function always returns false so it can be easily used in benchmark
+ * runners as
+ *
+ * @code
+ * if (error) {
+ *     return bench_run_fail(run, "we failed");
+ * }
+ * @endcode
+ *
+ * @param run Current benchmark run.
+ * @param fmt printf-style message followed by extra arguments.
+ * @retval false Always.
+ */
+bool bench_run_fail(bench_run_t *run, const char *fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	vsnprintf(run->error_buffer, run->error_buffer_size, fmt, args);
+	va_end(args);
+
+	return false;
+}
+
+/** @}
+ */