cat << EOF | patch -p1 --verbose
diff -urw intel-gpu-tools-1.9/overlay/gpu-perf.c intel-gpu-tools-1.9.new/overlay/gpu-perf.c
--- intel-gpu-tools-1.9/overlay/gpu-perf.c	2014-12-12 17:08:14.000000000 +0100
+++ intel-gpu-tools-1.9.new/overlay/gpu-perf.c	2017-08-19 04:12:19.046287078 +0200
@@ -48,6 +48,11 @@
 #define wmb()           asm volatile("sfence" ::: "memory")
 #endif
 
+#if !defined(rmb)
+#define rmb()           {}
+#define wmb()           {}
+#endif
+
 #define N_PAGES 32
 
 struct sample_event {
EOF