Merge branch 'rs/use-div-round-up'

Code cleanup.

* rs/use-div-round-up:
  use DIV_ROUND_UP

builtin/grep.c

@@ -543,7 +543,7 @@ static void compile_submodule_options(const struct grep_opt *opt,
 	 * submodule process has its own thread pool.
 	 */
 	argv_array_pushf(&submodule_options, "--threads=%d",
-			 (num_threads + 1) / 2);
+			 DIV_ROUND_UP(num_threads, 2));
 
 	/* Add Pathspecs */
 	argv_array_push(&submodule_options, "--");