[S390] Enable tick based perf_counter on s390.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/Kconfig

@@ -94,6 +94,7 @@ config S390
 	select HAVE_KVM if 64BIT
 	select HAVE_ARCH_TRACEHOOK
 	select INIT_ALL_POSSIBLE
+	select HAVE_PERF_COUNTERS
 
 source "init/Kconfig"
 

arch/s390/include/asm/perf_counter.h

+/*
+ * Performance counter support - s390 specific definitions.
+ *
+ * Copyright 2009 Martin Schwidefsky, IBM Corporation.
+ */
+
+static inline void set_perf_counter_pending(void) {}
+static inline void clear_perf_counter_pending(void) {}

tools/perf/perf.h

@@ -13,6 +13,12 @@
 #define cpu_relax()	asm volatile ("" ::: "memory");
 #endif
 
+#ifdef __s390__
+#include "../../arch/s390/include/asm/unistd.h"
+#define rmb()		asm volatile("bcr 15,0" ::: "memory")
+#define cpu_relax()	asm volatile("" ::: "memory");
+#endif
+
 #include <time.h>
 #include <unistd.h>
 #include <sys/types.h>