[S390] ftrace: add dynamic ftrace support

Dynamic ftrace support for s390.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index cf09948faad6..fb263736826c 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -11,6 +11,7 @@
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/ctype.h>
+#include <linux/ftrace.h>
 #include <linux/lockdep.h>
 #include <linux/module.h>
 #include <linux/pfn.h>
@@ -410,5 +411,8 @@ void __init startup_init(void)
         sclp_facilities_detect();
         detect_memory_layout(memory_chunk);
         S390_lowcore.machine_flags = machine_flags;
+#ifdef CONFIG_DYNAMIC_FTRACE
+        S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
+#endif
         lockdep_on();
 }