diff --git a/src/haproxy.c b/src/haproxy.c
index 1d2971d4b..c71482224 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -52,9 +52,11 @@
 #include <grp.h>
 #ifdef USE_CPU_AFFINITY
 #include <sched.h>
-#ifdef __FreeBSD__
+#if defined(__FreeBSD__) || defined(__DragonFly__)
 #include <sys/param.h>
+#ifdef __FreeBSD__
 #include <sys/cpuset.h>
+#endif
 #include <pthread_np.h>
 #endif
 #endif