diff --git a/rpcs3/util/cpu_stats.cpp b/rpcs3/util/cpu_stats.cpp
index de1d3b133c..c2a63fb35f 100644
--- a/rpcs3/util/cpu_stats.cpp
+++ b/rpcs3/util/cpu_stats.cpp
@@ -32,6 +32,7 @@
 
 #if defined(__DragonFly__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
 # include <sys/sysctl.h>
+# include <unistd.h>
 # if defined(__DragonFly__) || defined(__FreeBSD__)
 #  include <sys/user.h>
 # endif