Linux v6.18.37 · 원본 파일 · 온라인 원본
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * arch/arm64/include/asm/ftrace.h
4 *
5 * Copyright (C) 2013 Linaro Limited
6 * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
7 */
8#ifndef __ASM_FTRACE_H
9#define __ASM_FTRACE_H
10
11#include <asm/insn.h>
12
13#define HAVE_FUNCTION_GRAPH_FP_TEST
14
15#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
16#define ARCH_SUPPORTS_FTRACE_OPS 1
17#else
18#define MCOUNT_ADDR ((unsigned long)_mcount)
19#endif
20
21/* The BL at the callsite's adjusted rec->ip */
22#define MCOUNT_INSN_SIZE AARCH64_INSN_SIZE
23
24#define FTRACE_PLT_IDX 0
25#define NR_FTRACE_PLTS 1
26
27/*
28 * Currently, gcc tends to save the link register after the local variables
29 * on the stack. This causes the max stack tracer to report the function
30 * frame sizes for the wrong functions. By defining
31 * ARCH_FTRACE_SHIFT_STACK_TRACER, it will tell the stack tracer to expect
32 * to find the return address on the stack after the local variables have
33 * been set up.
34 *
35 * Note, this may change in the future, and we will need to deal with that
36 * if it were to happen.
37 */
38#define ARCH_FTRACE_SHIFT_STACK_TRACER 1
39
40#ifndef __ASSEMBLY__
41#include <linux/compat.h>
42
43extern void _mcount(unsigned long);
44extern void *return_address(unsigned int);
45
46struct dyn_arch_ftrace {
47 /* No extra data needed for arm64 */
48};
49
50extern unsigned long ftrace_graph_call;
51
52extern void return_to_handler(void);
53
54unsigned long ftrace_call_adjust(unsigned long addr);
55unsigned long arch_ftrace_get_symaddr(unsigned long fentry_ip);
56#define ftrace_get_symaddr(fentry_ip) arch_ftrace_get_symaddr(fentry_ip)
57
58#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
59#define HAVE_ARCH_FTRACE_REGS
60struct dyn_ftrace;
61struct ftrace_ops;
62struct ftrace_regs;
63#define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs))
64
65#define arch_ftrace_get_regs(regs) NULL
66
67/*
68 * Note: sizeof(struct ftrace_regs) must be a multiple of 16 to ensure correct
69 * stack alignment
70 */
71struct __arch_ftrace_regs {
72 /* x0 - x8 */
73 unsigned long regs[9];
74
75#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
76 unsigned long direct_tramp;
77#else
78 unsigned long __unused;
79#endif
80
81 unsigned long fp;
82 unsigned long lr;
83
84 unsigned long sp;
85 unsigned long pc;
86};
87
88static __always_inline unsigned long
89ftrace_regs_get_instruction_pointer(const struct ftrace_regs *fregs)
90{
91 return arch_ftrace_regs(fregs)->pc;
92}
93
94static __always_inline void
95ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
96 unsigned long pc)
97{
98 arch_ftrace_regs(fregs)->pc = pc;
99}
100
101static __always_inline unsigned long
102ftrace_regs_get_stack_pointer(const struct ftrace_regs *fregs)
103{
104 return arch_ftrace_regs(fregs)->sp;
105}
106
107static __always_inline unsigned long
108ftrace_regs_get_argument(struct ftrace_regs *fregs, unsigned int n)
109{
110 if (n < 8)
111 return arch_ftrace_regs(fregs)->regs[n];
112 return 0;
113}
114
115static __always_inline unsigned long
116ftrace_regs_get_return_value(const struct ftrace_regs *fregs)
117{
118 return arch_ftrace_regs(fregs)->regs[0];
119}
120
121static __always_inline void
122ftrace_regs_set_return_value(struct ftrace_regs *fregs,
123 unsigned long ret)
124{
125 arch_ftrace_regs(fregs)->regs[0] = ret;
126}
127
128static __always_inline void
129ftrace_override_function_with_return(struct ftrace_regs *fregs)
130{
131 arch_ftrace_regs(fregs)->pc = arch_ftrace_regs(fregs)->lr;
132}
133
134static __always_inline unsigned long
135ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs)
136{
137 return arch_ftrace_regs(fregs)->fp;
138}
139
140static __always_inline unsigned long
141ftrace_regs_get_return_address(const struct ftrace_regs *fregs)
142{
143 return arch_ftrace_regs(fregs)->lr;
144}
145
146static __always_inline struct pt_regs *
147ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs)
148{
149 struct __arch_ftrace_regs *afregs = arch_ftrace_regs(fregs);
150
151 memcpy(regs->regs, afregs->regs, sizeof(afregs->regs));
152 regs->sp = afregs->sp;
153 regs->pc = afregs->pc;
154 regs->regs[29] = afregs->fp;
155 regs->regs[30] = afregs->lr;
156 regs->pstate = PSR_MODE_EL1h;
157 return regs;
158}
159
160#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \
161 (_regs)->pc = arch_ftrace_regs(fregs)->pc; \
162 (_regs)->regs[29] = arch_ftrace_regs(fregs)->fp; \
163 (_regs)->sp = arch_ftrace_regs(fregs)->sp; \
164 (_regs)->pstate = PSR_MODE_EL1h; \
165 } while (0)
166
167int ftrace_regs_query_register_offset(const char *name);
168
169int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
170#define ftrace_init_nop ftrace_init_nop
171
172void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
173 struct ftrace_ops *op, struct ftrace_regs *fregs);
174#define ftrace_graph_func ftrace_graph_func
175
176#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
177static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs,
178 unsigned long addr)
179{
180 /*
181 * The ftrace trampoline will return to this address instead of the
182 * instrumented function.
183 */
184 arch_ftrace_regs(fregs)->direct_tramp = addr;
185}
186#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
187
188#endif
189
190#define ftrace_return_address(n) return_address(n)
191
192/*
193 * Because AArch32 mode does not share the same syscall table with AArch64,
194 * tracing compat syscalls may result in reporting bogus syscalls or even
195 * hang-up, so just do not trace them.
196 * See kernel/trace/trace_syscalls.c
197 *
198 * x86 code says:
199 * If the user really wants these, then they should use the
200 * raw syscall tracepoints with filtering.
201 */
202#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
203static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
204{
205 return is_compat_task();
206}
207
208#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
209
210static inline bool arch_syscall_match_sym_name(const char *sym,
211 const char *name)
212{
213 /*
214 * Since all syscall functions have __arm64_ prefix, we must skip it.
215 * However, as we described above, we decided to ignore compat
216 * syscalls, so we don't care about __arm64_compat_ prefix here.
217 */
218 return !strcmp(sym + 8, name);
219}
220#endif /* ifndef __ASSEMBLY__ */
221
222#ifndef __ASSEMBLY__
223#ifdef CONFIG_FUNCTION_GRAPH_TRACER
224
225void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent,
226 unsigned long frame_pointer);
227
228#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */
229#endif
230
231#endif /* __ASM_FTRACE_H */