arch/x86/include/asm/ftrace.h

   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 #ifdef CONFIG_DYNAMIC_FTRACE
  13 #define ARCH_SUPPORTS_FTRACE_OPS 1
  14 #endif
  15
  16 #define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
  17
  18 #ifndef __ASSEMBLY__
  19 extern atomic_t modifying_ftrace_code;
  20 extern void __fentry__(void);
  21
  22 static inline unsigned long ftrace_call_adjust(unsigned long addr)
  23 {
  24         /*
  25          * addr is the address of the mcount call instruction.
  26          * recordmcount does the necessary offset calculation.
  27          */
  28         return addr;
  29 }
  30
  31 /*
  32  * When a ftrace registered caller is tracing a function that is
  33  * also set by a register_ftrace_direct() call, it needs to be
  34  * differentiated in the ftrace_caller trampoline. To do this, we
  35  * place the direct caller in the ORIG_AX part of pt_regs. This
  36  * tells the ftrace_caller that there's a direct caller.
  37  */
  38 static inline void arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr)
  39 {
  40         /* Emulate a call */
  41         regs->orig_ax = addr;
  42 }
  43
  44 #ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
  45 struct ftrace_regs {
  46         struct pt_regs          regs;
  47 };
  48
  49 static __always_inline struct pt_regs *
  50 arch_ftrace_get_regs(struct ftrace_regs *fregs)
  51 {
  52         /* Only when FL_SAVE_REGS is set, cs will be non zero */
  53         if (!fregs->regs.cs)
  54                 return NULL;
  55         return &fregs->regs;
  56 }
  57
  58 #define ftrace_instruction_pointer_set(fregs, _ip)      \
  59         do { (fregs)->regs.ip = (_ip); } while (0)
  60 #endif
  61
  62 #ifdef CONFIG_DYNAMIC_FTRACE
  63
  64 struct dyn_arch_ftrace {
  65         /* No extra data needed for x86 */
  66 };
  67
  68 #define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR
  69
  70 #endif /*  CONFIG_DYNAMIC_FTRACE */
  71 #endif /* __ASSEMBLY__ */
  72 #endif /* CONFIG_FUNCTION_TRACER */
  73
  74
  75 #ifndef __ASSEMBLY__
  76
  77 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
  78 extern void set_ftrace_ops_ro(void);
  79 #else
  80 static inline void set_ftrace_ops_ro(void) { }
  81 #endif
  82
  83 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
  84 static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
  85 {
  86         /*
  87          * Compare the symbol name with the system call name. Skip the
  88          * "__x64_sys", "__ia32_sys", "__do_sys" or simple "sys" prefix.
  89          */
  90         return !strcmp(sym + 3, name + 3) ||
  91                 (!strncmp(sym, "__x64_", 6) && !strcmp(sym + 9, name + 3)) ||
  92                 (!strncmp(sym, "__ia32_", 7) && !strcmp(sym + 10, name + 3)) ||
  93                 (!strncmp(sym, "__do_sys", 8) && !strcmp(sym + 8, name + 3));
  94 }
  95
  96 #ifndef COMPILE_OFFSETS
  97
  98 #if defined(CONFIG_FTRACE_SYSCALLS) && defined(CONFIG_IA32_EMULATION)
  99 #include <linux/compat.h>
 100
 101 /*
 102  * Because ia32 syscalls do not map to x86_64 syscall numbers
 103  * this screws up the trace output when tracing a ia32 task.
 104  * Instead of reporting bogus syscalls, just do not trace them.
 105  *
 106  * If the user really wants these, then they should use the
 107  * raw syscall tracepoints with filtering.
 108  */
 109 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 1
 110 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
 111 {
 112         return in_32bit_syscall();
 113 }
 114 #endif /* CONFIG_FTRACE_SYSCALLS && CONFIG_IA32_EMULATION */
 115 #endif /* !COMPILE_OFFSETS */
 116 #endif /* !__ASSEMBLY__ */
 117
 118 #endif /* _ASM_X86_FTRACE_H */