xref: /linux/arch/powerpc/include/asm/ftrace.h (revision 417552999d0b6681ac30e117ae890828ca7e46b3)
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 __ASSEMBLER__
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 
arch_ftrace_get_regs(struct ftrace_regs * fregs)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 #define arch_ftrace_fill_perf_regs(fregs, _regs) do {		\
47 		(_regs)->result = 0;				\
48 		(_regs)->nip = arch_ftrace_regs(fregs)->regs.nip;		\
49 		(_regs)->gpr[1] = arch_ftrace_regs(fregs)->regs.gpr[1];		\
50 		asm volatile("mfmsr %0" : "=r" ((_regs)->msr));	\
51 	} while (0)
52 
53 #undef ftrace_regs_get_return_value
54 static __always_inline unsigned long
ftrace_regs_get_return_value(const struct ftrace_regs * fregs)55 ftrace_regs_get_return_value(const struct ftrace_regs *fregs)
56 {
57 	return arch_ftrace_regs(fregs)->regs.gpr[3];
58 }
59 #define ftrace_regs_get_return_value ftrace_regs_get_return_value
60 
61 #undef ftrace_regs_get_frame_pointer
62 static __always_inline unsigned long
ftrace_regs_get_frame_pointer(const struct ftrace_regs * fregs)63 ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs)
64 {
65 	return arch_ftrace_regs(fregs)->regs.gpr[1];
66 }
67 
68 static __always_inline void
ftrace_regs_set_instruction_pointer(struct ftrace_regs * fregs,unsigned long ip)69 ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
70 				    unsigned long ip)
71 {
72 	regs_set_return_ip(&arch_ftrace_regs(fregs)->regs, ip);
73 }
74 
75 static __always_inline unsigned long
ftrace_regs_get_return_address(struct ftrace_regs * fregs)76 ftrace_regs_get_return_address(struct ftrace_regs *fregs)
77 {
78 	return arch_ftrace_regs(fregs)->regs.link;
79 }
80 
81 struct ftrace_ops;
82 
83 #define ftrace_graph_func ftrace_graph_func
84 void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
85 		       struct ftrace_ops *op, struct ftrace_regs *fregs);
86 #endif
87 #endif /* __ASSEMBLER__ */
88 
89 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
90 #define ARCH_SUPPORTS_FTRACE_OPS 1
91 #endif
92 #endif /* CONFIG_FUNCTION_TRACER */
93 
94 #ifndef __ASSEMBLER__
95 #ifdef CONFIG_FTRACE_SYSCALLS
96 /*
97  * Some syscall entry functions on powerpc start with "ppc_" (fork and clone,
98  * for instance) or ppc32_/ppc64_. We should also match the sys_ variant with
99  * those.
100  */
101 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
arch_syscall_match_sym_name(const char * sym,const char * name)102 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
103 {
104 	return !strcmp(sym, name) ||
105 		(!strncmp(sym, "__se_sys", 8) && !strcmp(sym + 5, name)) ||
106 		(!strncmp(sym, "ppc_", 4) && !strcmp(sym + 4, name + 4)) ||
107 		(!strncmp(sym, "ppc32_", 6) && !strcmp(sym + 6, name + 4)) ||
108 		(!strncmp(sym, "ppc64_", 6) && !strcmp(sym + 6, name + 4));
109 }
110 #endif /* CONFIG_FTRACE_SYSCALLS */
111 
112 #if defined(CONFIG_PPC64) && defined(CONFIG_FUNCTION_TRACER)
113 #include <asm/paca.h>
114 
this_cpu_disable_ftrace(void)115 static inline void this_cpu_disable_ftrace(void)
116 {
117 	get_paca()->ftrace_enabled = 0;
118 }
119 
this_cpu_enable_ftrace(void)120 static inline void this_cpu_enable_ftrace(void)
121 {
122 	get_paca()->ftrace_enabled = 1;
123 }
124 
125 /* Disable ftrace on this CPU if possible (may not be implemented) */
this_cpu_set_ftrace_enabled(u8 ftrace_enabled)126 static inline void this_cpu_set_ftrace_enabled(u8 ftrace_enabled)
127 {
128 	get_paca()->ftrace_enabled = ftrace_enabled;
129 }
130 
this_cpu_get_ftrace_enabled(void)131 static inline u8 this_cpu_get_ftrace_enabled(void)
132 {
133 	return get_paca()->ftrace_enabled;
134 }
135 #else /* CONFIG_PPC64 */
this_cpu_disable_ftrace(void)136 static inline void this_cpu_disable_ftrace(void) { }
this_cpu_enable_ftrace(void)137 static inline void this_cpu_enable_ftrace(void) { }
this_cpu_set_ftrace_enabled(u8 ftrace_enabled)138 static inline void this_cpu_set_ftrace_enabled(u8 ftrace_enabled) { }
this_cpu_get_ftrace_enabled(void)139 static inline u8 this_cpu_get_ftrace_enabled(void) { return 1; }
140 #endif /* CONFIG_PPC64 */
141 
142 #ifdef CONFIG_FUNCTION_TRACER
143 extern unsigned int ftrace_tramp_text[], ftrace_tramp_init[];
144 #ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
145 struct ftrace_ool_stub {
146 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS
147 	struct ftrace_ops *ftrace_op;
148 #endif
149 	u32	insn[4];
150 } __aligned(sizeof(unsigned long));
151 extern struct ftrace_ool_stub ftrace_ool_stub_text_end[], ftrace_ool_stub_text[],
152 			      ftrace_ool_stub_inittext[];
153 extern unsigned int ftrace_ool_stub_text_end_count, ftrace_ool_stub_text_count,
154 		    ftrace_ool_stub_inittext_count;
155 #endif
156 void ftrace_free_init_tramp(void);
157 unsigned long ftrace_call_adjust(unsigned long addr);
158 
159 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
160 /*
161  * When an ftrace registered caller is tracing a function that is also set by a
162  * register_ftrace_direct() call, it needs to be differentiated in the
163  * ftrace_caller trampoline so that the direct call can be invoked after the
164  * other ftrace ops. To do this, place the direct caller in the orig_gpr3 field
165  * of pt_regs. This tells ftrace_caller that there's a direct caller.
166  */
arch_ftrace_set_direct_caller(struct ftrace_regs * fregs,unsigned long addr)167 static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs, unsigned long addr)
168 {
169 	struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;
170 
171 	regs->orig_gpr3 = addr;
172 }
173 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
174 #else
ftrace_free_init_tramp(void)175 static inline void ftrace_free_init_tramp(void) { }
ftrace_call_adjust(unsigned long addr)176 static inline unsigned long ftrace_call_adjust(unsigned long addr) { return addr; }
177 #endif
178 #endif /* !__ASSEMBLER__ */
179 
180 #endif /* _ASM_POWERPC_FTRACE */
181