xref: /linux/arch/x86/include/asm/ftrace.h (revision 497e6b37b0099dc415578488287fd84fb74433eb)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_FTRACE_H
3 #define _ASM_X86_FTRACE_H
4 
5 #ifdef CONFIG_FUNCTION_TRACER
6 #ifndef CC_USING_FENTRY
7 # error Compiler does not support fentry?
8 #endif
9 # define MCOUNT_ADDR		((unsigned long)(__fentry__))
10 #define MCOUNT_INSN_SIZE	5 /* sizeof mcount call */
11 
12 /* Ignore unused weak functions which will have non zero offsets */
13 #ifdef CONFIG_HAVE_FENTRY
14 # include <asm/ibt.h>
15 /* Add offset for endbr64 if IBT enabled */
16 # define FTRACE_MCOUNT_MAX_OFFSET	ENDBR_INSN_SIZE
17 #endif
18 
19 #ifdef CONFIG_DYNAMIC_FTRACE
20 #define ARCH_SUPPORTS_FTRACE_OPS 1
21 #endif
22 
23 #define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
24 
25 #ifndef __ASSEMBLY__
26 extern void __fentry__(void);
27 
28 static inline unsigned long ftrace_call_adjust(unsigned long addr)
29 {
30 	/*
31 	 * addr is the address of the mcount call instruction.
32 	 * recordmcount does the necessary offset calculation.
33 	 */
34 	return addr;
35 }
36 
37 #ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
38 struct ftrace_regs {
39 	struct pt_regs		regs;
40 };
41 
42 static __always_inline struct pt_regs *
43 arch_ftrace_get_regs(struct ftrace_regs *fregs)
44 {
45 	/* Only when FL_SAVE_REGS is set, cs will be non zero */
46 	if (!fregs->regs.cs)
47 		return NULL;
48 	return &fregs->regs;
49 }
50 
51 #define ftrace_regs_set_instruction_pointer(fregs, _ip)	\
52 	do { (fregs)->regs.ip = (_ip); } while (0)
53 
54 #define ftrace_regs_get_instruction_pointer(fregs) \
55 	((fregs)->regs.ip)
56 
57 #define ftrace_regs_get_argument(fregs, n) \
58 	regs_get_kernel_argument(&(fregs)->regs, n)
59 #define ftrace_regs_get_stack_pointer(fregs) \
60 	kernel_stack_pointer(&(fregs)->regs)
61 #define ftrace_regs_return_value(fregs) \
62 	regs_return_value(&(fregs)->regs)
63 #define ftrace_regs_set_return_value(fregs, ret) \
64 	regs_set_return_value(&(fregs)->regs, ret)
65 #define ftrace_override_function_with_return(fregs) \
66 	override_function_with_return(&(fregs)->regs)
67 #define ftrace_regs_query_register_offset(name) \
68 	regs_query_register_offset(name)
69 
70 struct ftrace_ops;
71 #define ftrace_graph_func ftrace_graph_func
72 void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
73 		       struct ftrace_ops *op, struct ftrace_regs *fregs);
74 #else
75 #define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR
76 #endif
77 
78 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
79 /*
80  * When a ftrace registered caller is tracing a function that is
81  * also set by a register_ftrace_direct() call, it needs to be
82  * differentiated in the ftrace_caller trampoline. To do this, we
83  * place the direct caller in the ORIG_AX part of pt_regs. This
84  * tells the ftrace_caller that there's a direct caller.
85  */
86 static inline void
87 __arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr)
88 {
89 	/* Emulate a call */
90 	regs->orig_ax = addr;
91 }
92 #define arch_ftrace_set_direct_caller(fregs, addr) \
93 	__arch_ftrace_set_direct_caller(&(fregs)->regs, addr)
94 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
95 
96 #ifdef CONFIG_DYNAMIC_FTRACE
97 
98 struct dyn_arch_ftrace {
99 	/* No extra data needed for x86 */
100 };
101 
102 #endif /*  CONFIG_DYNAMIC_FTRACE */
103 #endif /* __ASSEMBLY__ */
104 #endif /* CONFIG_FUNCTION_TRACER */
105 
106 
107 #ifndef __ASSEMBLY__
108 
109 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
110 extern void set_ftrace_ops_ro(void);
111 #else
112 static inline void set_ftrace_ops_ro(void) { }
113 #endif
114 
115 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
116 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
117 {
118 	/*
119 	 * Compare the symbol name with the system call name. Skip the
120 	 * "__x64_sys", "__ia32_sys", "__do_sys" or simple "sys" prefix.
121 	 */
122 	return !strcmp(sym + 3, name + 3) ||
123 		(!strncmp(sym, "__x64_", 6) && !strcmp(sym + 9, name + 3)) ||
124 		(!strncmp(sym, "__ia32_", 7) && !strcmp(sym + 10, name + 3)) ||
125 		(!strncmp(sym, "__do_sys", 8) && !strcmp(sym + 8, name + 3));
126 }
127 
128 #ifndef COMPILE_OFFSETS
129 
130 #if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_IA32_EMULATION)
131 #include <linux/compat.h>
132 
133 /*
134  * Because ia32 syscalls do not map to x86_64 syscall numbers
135  * this screws up the trace output when tracing a ia32 task.
136  * Instead of reporting bogus syscalls, just do not trace them.
137  *
138  * If the user really wants these, then they should use the
139  * raw syscall tracepoints with filtering.
140  */
141 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 1
142 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
143 {
144 	return in_32bit_syscall();
145 }
146 #endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_IA32_EMULATION */
147 #endif /* !COMPILE_OFFSETS */
148 #endif /* !__ASSEMBLY__ */
149 
150 #endif /* _ASM_X86_FTRACE_H */
151