ftrace.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef _ASM_X86_FTRACE_H
  3#define _ASM_X86_FTRACE_H
  4
  5#include <asm/ptrace.h>
  6
  7#ifdef CONFIG_FUNCTION_TRACER
  8#ifndef CC_USING_FENTRY
  9# error Compiler does not support fentry?
 10#endif
 11# define MCOUNT_ADDR		((unsigned long)(__fentry__))
 12#define MCOUNT_INSN_SIZE	5 /* sizeof mcount call */
 13
 14/* Ignore unused weak functions which will have non zero offsets */
 15#ifdef CONFIG_HAVE_FENTRY
 16# include <asm/ibt.h>
 17/* Add offset for endbr64 if IBT enabled */
 18# define FTRACE_MCOUNT_MAX_OFFSET	ENDBR_INSN_SIZE
 19#endif
 20
 21#ifdef CONFIG_DYNAMIC_FTRACE
 22#define ARCH_SUPPORTS_FTRACE_OPS 1
 23#endif
 24
 25#ifndef __ASSEMBLER__
 26extern void __fentry__(void);
 27
 28static 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
 37static inline unsigned long arch_ftrace_get_symaddr(unsigned long fentry_ip)
 38{
 39	if (is_endbr((void*)(fentry_ip - ENDBR_INSN_SIZE)))
 40		fentry_ip -= ENDBR_INSN_SIZE;
 41
 42	return fentry_ip;
 43}
 44#define ftrace_get_symaddr(fentry_ip)	arch_ftrace_get_symaddr(fentry_ip)
 45
 46#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
 47
 48#include <linux/ftrace_regs.h>
 49
 50static __always_inline struct pt_regs *
 51arch_ftrace_get_regs(struct ftrace_regs *fregs)
 52{
 53	/* Only when FL_SAVE_REGS is set, cs will be non zero */
 54	if (!arch_ftrace_regs(fregs)->regs.cs)
 55		return NULL;
 56	return &arch_ftrace_regs(fregs)->regs;
 57}
 58
 59#define arch_ftrace_partial_regs(regs) do {	\
 60	regs->flags |= X86_EFLAGS_FIXED;	\
 61	regs->cs = __KERNEL_CS;			\
 62} while (0)
 63
 64#define arch_ftrace_fill_perf_regs(fregs, _regs) do {	\
 65		(_regs)->ip = arch_ftrace_regs(fregs)->regs.ip;		\
 66		(_regs)->sp = arch_ftrace_regs(fregs)->regs.sp;		\
 67		(_regs)->cs = __KERNEL_CS;		\
 68		(_regs)->flags = 0;			\
 69	} while (0)
 70
 71#define ftrace_regs_set_instruction_pointer(fregs, _ip)	\
 72	do { arch_ftrace_regs(fregs)->regs.ip = (_ip); } while (0)
 73
 74
 75static __always_inline unsigned long
 76ftrace_regs_get_return_address(struct ftrace_regs *fregs)
 77{
 78	return *(unsigned long *)ftrace_regs_get_stack_pointer(fregs);
 79}
 80
 81struct ftrace_ops;
 82#define ftrace_graph_func ftrace_graph_func
 83void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
 84		       struct ftrace_ops *op, struct ftrace_regs *fregs);
 85#else
 86#define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR
 87#endif
 88
 89#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
 90/*
 91 * When a ftrace registered caller is tracing a function that is
 92 * also set by a register_ftrace_direct() call, it needs to be
 93 * differentiated in the ftrace_caller trampoline. To do this, we
 94 * place the direct caller in the ORIG_AX part of pt_regs. This
 95 * tells the ftrace_caller that there's a direct caller.
 96 */
 97static inline void
 98__arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr)
 99{
100	/* Emulate a call */
101	regs->orig_ax = addr;
102}
103#define arch_ftrace_set_direct_caller(fregs, addr) \
104	__arch_ftrace_set_direct_caller(&arch_ftrace_regs(fregs)->regs, addr)
105#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
106
107#ifdef CONFIG_DYNAMIC_FTRACE
108
109struct dyn_arch_ftrace {
110	/* No extra data needed for x86 */
111};
112
113#endif /*  CONFIG_DYNAMIC_FTRACE */
114#endif /* __ASSEMBLER__ */
115#endif /* CONFIG_FUNCTION_TRACER */
116
117
118#ifndef __ASSEMBLER__
119
120void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
121			   unsigned long frame_pointer);
122
123#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
124extern void set_ftrace_ops_ro(void);
125#else
126static inline void set_ftrace_ops_ro(void) { }
127#endif
128
129#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
130static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
131{
132	/*
133	 * Compare the symbol name with the system call name. Skip the
134	 * "__x64_sys", "__ia32_sys", "__do_sys" or simple "sys" prefix.
135	 */
136	return !strcmp(sym + 3, name + 3) ||
137		(!strncmp(sym, "__x64_", 6) && !strcmp(sym + 9, name + 3)) ||
138		(!strncmp(sym, "__ia32_", 7) && !strcmp(sym + 10, name + 3)) ||
139		(!strncmp(sym, "__do_sys", 8) && !strcmp(sym + 8, name + 3));
140}
141
142#ifndef COMPILE_OFFSETS
143
144#if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_IA32_EMULATION)
145#include <linux/compat.h>
146
147/*
148 * Because ia32 syscalls do not map to x86_64 syscall numbers
149 * this screws up the trace output when tracing a ia32 task.
150 * Instead of reporting bogus syscalls, just do not trace them.
151 *
152 * If the user really wants these, then they should use the
153 * raw syscall tracepoints with filtering.
154 */
155#define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 1
156static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
157{
158	return in_32bit_syscall();
159}
160#endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_IA32_EMULATION */
161#endif /* !COMPILE_OFFSETS */
162#endif /* !__ASSEMBLER__ */
163
164#endif /* _ASM_X86_FTRACE_H */