1#ifndef _ASM_S390_FTRACE_H
2#define _ASM_S390_FTRACE_H
3
4#define ARCH_SUPPORTS_FTRACE_OPS 1
5
6#ifdef CC_USING_HOTPATCH
7#define MCOUNT_INSN_SIZE	6
8#else
9#define MCOUNT_INSN_SIZE	24
10#define MCOUNT_RETURN_FIXUP	18
11#endif
12
13#ifndef __ASSEMBLY__
14
15#define ftrace_return_address(n) __builtin_return_address(n)
16
17void _mcount(void);
18void ftrace_caller(void);
19
20extern char ftrace_graph_caller_end;
21extern unsigned long ftrace_plt;
22
23struct dyn_arch_ftrace { };
24
25#define MCOUNT_ADDR ((unsigned long)_mcount)
26#define FTRACE_ADDR ((unsigned long)ftrace_caller)
27
28#define KPROBE_ON_FTRACE_NOP	0
29#define KPROBE_ON_FTRACE_CALL	1
30
31static inline unsigned long ftrace_call_adjust(unsigned long addr)
32{
33	return addr;
34}
35
36struct ftrace_insn {
37	u16 opc;
38	s32 disp;
39} __packed;
40
41static inline void ftrace_generate_nop_insn(struct ftrace_insn *insn)
42{
43#ifdef CONFIG_FUNCTION_TRACER
44#ifdef CC_USING_HOTPATCH
45	/* brcl 0,0 */
46	insn->opc = 0xc004;
47	insn->disp = 0;
48#else
49	/* jg .+24 */
50	insn->opc = 0xc0f4;
51	insn->disp = MCOUNT_INSN_SIZE / 2;
52#endif
53#endif
54}
55
56static inline int is_ftrace_nop(struct ftrace_insn *insn)
57{
58#ifdef CONFIG_FUNCTION_TRACER
59#ifdef CC_USING_HOTPATCH
60	if (insn->disp == 0)
61		return 1;
62#else
63	if (insn->disp == MCOUNT_INSN_SIZE / 2)
64		return 1;
65#endif
66#endif
67	return 0;
68}
69
70static inline void ftrace_generate_call_insn(struct ftrace_insn *insn,
71					     unsigned long ip)
72{
73#ifdef CONFIG_FUNCTION_TRACER
74	unsigned long target;
75
76	/* brasl r0,ftrace_caller */
77	target = is_module_addr((void *) ip) ? ftrace_plt : FTRACE_ADDR;
78	insn->opc = 0xc005;
79	insn->disp = (target - ip) / 2;
80#endif
81}
82
83#endif /* __ASSEMBLY__ */
84#endif /* _ASM_S390_FTRACE_H */
85