1 files changed, 49 insertions, 5 deletions

diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h
index 3aef8afec336..abb618f1ead2 100644
--- a/arch/s390/include/asm/ftrace.h
+++ b/arch/s390/include/asm/ftrace.h
@@ -1,25 +1,69 @@
 #ifndef _ASM_S390_FTRACE_H
 #define _ASM_S390_FTRACE_H
 
+#define ARCH_SUPPORTS_FTRACE_OPS 1
+
+#define MCOUNT_INSN_SIZE        24
+#define MCOUNT_RETURN_FIXUP     18
+
 #ifndef __ASSEMBLY__
 
-extern void _mcount(void);
+#define ftrace_return_address(n) __builtin_return_address(n)
+
+void _mcount(void);
+void ftrace_caller(void);
+
 extern char ftrace_graph_caller_end;
+extern unsigned long ftrace_plt;
 
 struct dyn_arch_ftrace { };
 
-#define MCOUNT_ADDR ((long)_mcount)
+#define MCOUNT_ADDR ((unsigned long)_mcount)
+#define FTRACE_ADDR ((unsigned long)ftrace_caller)
 
+#define KPROBE_ON_FTRACE_NOP    0
+#define KPROBE_ON_FTRACE_CALL   1
 
 static inline unsigned long ftrace_call_adjust(unsigned long addr)
 {
         return addr;
 }
 
-#endif /* __ASSEMBLY__ */
+struct ftrace_insn {
+        u16 opc;
+        s32 disp;
+} __packed;
+
+static inline void ftrace_generate_nop_insn(struct ftrace_insn *insn)
+{
+#ifdef CONFIG_FUNCTION_TRACER
+        /* jg .+24 */
+        insn->opc = 0xc0f4;
+        insn->disp = MCOUNT_INSN_SIZE / 2;
+#endif
+}
 
-#define MCOUNT_INSN_SIZE  18
+static inline int is_ftrace_nop(struct ftrace_insn *insn)
+{
+#ifdef CONFIG_FUNCTION_TRACER
+        if (insn->disp == MCOUNT_INSN_SIZE / 2)
+                return 1;
+#endif
+        return 0;
+}
 
-#define ARCH_SUPPORTS_FTRACE_OPS 1
+static inline void ftrace_generate_call_insn(struct ftrace_insn *insn,
+                                             unsigned long ip)
+{
+#ifdef CONFIG_FUNCTION_TRACER
+        unsigned long target;
+
+        /* brasl r0,ftrace_caller */
+        target = is_module_addr((void *) ip) ? ftrace_plt : FTRACE_ADDR;
+        insn->opc = 0xc005;
+        insn->disp = (target - ip) / 2;
+#endif
+}
 
+#endif /* __ASSEMBLY__ */
 #endif /* _ASM_S390_FTRACE_H */