xref: /linux/arch/powerpc/include/asm/ftrace.h (revision 7f4f3b14e8079ecde096bd734af10e30d40c27b7)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_FTRACE
3 #define _ASM_POWERPC_FTRACE
4 
5 #include <asm/types.h>
6 
7 #ifdef CONFIG_FUNCTION_TRACER
8 #define MCOUNT_ADDR		((unsigned long)(_mcount))
9 #define MCOUNT_INSN_SIZE	4 /* sizeof mcount call */
10 
11 /* Ignore unused weak functions which will have larger offsets */
12 #if defined(CONFIG_MPROFILE_KERNEL) || defined(CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY)
13 #define FTRACE_MCOUNT_MAX_OFFSET	16
14 #elif defined(CONFIG_PPC32)
15 #define FTRACE_MCOUNT_MAX_OFFSET	8
16 #endif
17 
18 #ifndef __ASSEMBLY__
19 extern void _mcount(void);
20 
21 unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip,
22 				    unsigned long sp);
23 
24 struct module;
25 struct dyn_ftrace;
26 struct dyn_arch_ftrace {
27 #ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
28 	/* pointer to the associated out-of-line stub */
29 	unsigned long ool_stub;
30 #endif
31 };
32 
33 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
34 #define ftrace_need_init_nop()	(true)
35 int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
36 #define ftrace_init_nop ftrace_init_nop
37 
38 #include <linux/ftrace_regs.h>
39 
40 static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs)
41 {
42 	/* We clear regs.msr in ftrace_call */
43 	return arch_ftrace_regs(fregs)->regs.msr ? &arch_ftrace_regs(fregs)->regs : NULL;
44 }
45 
46 static __always_inline void
47 ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
48 				    unsigned long ip)
49 {
50 	regs_set_return_ip(&arch_ftrace_regs(fregs)->regs, ip);
51 }
52 
53 struct ftrace_ops;
54 
55 #define ftrace_graph_func ftrace_graph_func
56 void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
57 		       struct ftrace_ops *op, struct ftrace_regs *fregs);
58 #endif
59 #endif /* __ASSEMBLY__ */
60 
61 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
62 #define ARCH_SUPPORTS_FTRACE_OPS 1
63 #endif
64 #endif /* CONFIG_FUNCTION_TRACER */
65 
66 #ifndef __ASSEMBLY__
67 #ifdef CONFIG_FTRACE_SYSCALLS
68 /*
69  * Some syscall entry functions on powerpc start with "ppc_" (fork and clone,
70  * for instance) or ppc32_/ppc64_. We should also match the sys_ variant with
71  * those.
72  */
73 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
74 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
75 {
76 	return !strcmp(sym, name) ||
77 		(!strncmp(sym, "__se_sys", 8) && !strcmp(sym + 5, name)) ||
78 		(!strncmp(sym, "ppc_", 4) && !strcmp(sym + 4, name + 4)) ||
79 		(!strncmp(sym, "ppc32_", 6) && !strcmp(sym + 6, name + 4)) ||
80 		(!strncmp(sym, "ppc64_", 6) && !strcmp(sym + 6, name + 4));
81 }
82 #endif /* CONFIG_FTRACE_SYSCALLS */
83 
84 #if defined(CONFIG_PPC64) && defined(CONFIG_FUNCTION_TRACER)
85 #include <asm/paca.h>
86 
87 static inline void this_cpu_disable_ftrace(void)
88 {
89 	get_paca()->ftrace_enabled = 0;
90 }
91 
92 static inline void this_cpu_enable_ftrace(void)
93 {
94 	get_paca()->ftrace_enabled = 1;
95 }
96 
97 /* Disable ftrace on this CPU if possible (may not be implemented) */
98 static inline void this_cpu_set_ftrace_enabled(u8 ftrace_enabled)
99 {
100 	get_paca()->ftrace_enabled = ftrace_enabled;
101 }
102 
103 static inline u8 this_cpu_get_ftrace_enabled(void)
104 {
105 	return get_paca()->ftrace_enabled;
106 }
107 #else /* CONFIG_PPC64 */
108 static inline void this_cpu_disable_ftrace(void) { }
109 static inline void this_cpu_enable_ftrace(void) { }
110 static inline void this_cpu_set_ftrace_enabled(u8 ftrace_enabled) { }
111 static inline u8 this_cpu_get_ftrace_enabled(void) { return 1; }
112 #endif /* CONFIG_PPC64 */
113 
114 #ifdef CONFIG_FUNCTION_TRACER
115 extern unsigned int ftrace_tramp_text[], ftrace_tramp_init[];
116 #ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
117 struct ftrace_ool_stub {
118 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS
119 	struct ftrace_ops *ftrace_op;
120 #endif
121 	u32	insn[4];
122 } __aligned(sizeof(unsigned long));
123 extern struct ftrace_ool_stub ftrace_ool_stub_text_end[], ftrace_ool_stub_text[],
124 			      ftrace_ool_stub_inittext[];
125 extern unsigned int ftrace_ool_stub_text_end_count, ftrace_ool_stub_text_count,
126 		    ftrace_ool_stub_inittext_count;
127 #endif
128 void ftrace_free_init_tramp(void);
129 unsigned long ftrace_call_adjust(unsigned long addr);
130 
131 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
132 /*
133  * When an ftrace registered caller is tracing a function that is also set by a
134  * register_ftrace_direct() call, it needs to be differentiated in the
135  * ftrace_caller trampoline so that the direct call can be invoked after the
136  * other ftrace ops. To do this, place the direct caller in the orig_gpr3 field
137  * of pt_regs. This tells ftrace_caller that there's a direct caller.
138  */
139 static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs, unsigned long addr)
140 {
141 	struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;
142 
143 	regs->orig_gpr3 = addr;
144 }
145 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
146 #else
147 static inline void ftrace_free_init_tramp(void) { }
148 static inline unsigned long ftrace_call_adjust(unsigned long addr) { return addr; }
149 #endif
150 #endif /* !__ASSEMBLY__ */
151 
152 #endif /* _ASM_POWERPC_FTRACE */
153