arch/x86/include/asm/ftrace.h

   1 #ifndef _ASM_X86_FTRACE_H
   2 #define _ASM_X86_FTRACE_H
   3
   4 #ifdef __ASSEMBLY__
   5
   6         .macro MCOUNT_SAVE_FRAME
   7         /* taken from glibc */
   8         subq $0x38, %rsp
   9         movq %rax, (%rsp)
  10         movq %rcx, 8(%rsp)
  11         movq %rdx, 16(%rsp)
  12         movq %rsi, 24(%rsp)
  13         movq %rdi, 32(%rsp)
  14         movq %r8, 40(%rsp)
  15         movq %r9, 48(%rsp)
  16         .endm
  17
  18         .macro MCOUNT_RESTORE_FRAME
  19         movq 48(%rsp), %r9
  20         movq 40(%rsp), %r8
  21         movq 32(%rsp), %rdi
  22         movq 24(%rsp), %rsi
  23         movq 16(%rsp), %rdx
  24         movq 8(%rsp), %rcx
  25         movq (%rsp), %rax
  26         addq $0x38, %rsp
  27         .endm
  28
  29 #endif
  30
  31 #ifdef CONFIG_FUNCTION_TRACER
  32 #define MCOUNT_ADDR             ((long)(mcount))
  33 #define MCOUNT_INSN_SIZE        5 /* sizeof mcount call */
  34
  35 #ifndef __ASSEMBLY__
  36 extern void mcount(void);
  37
  38 static inline unsigned long ftrace_call_adjust(unsigned long addr)
  39 {
  40         /*
  41          * call mcount is "e8 <4 byte offset>"
  42          * The addr points to the 4 byte offset and the caller of this
  43          * function wants the pointer to e8. Simply subtract one.
  44          */
  45         return addr - 1;
  46 }
  47
  48 #ifdef CONFIG_DYNAMIC_FTRACE
  49
  50 struct dyn_arch_ftrace {
  51         /* No extra data needed for x86 */
  52 };
  53
  54 #endif /*  CONFIG_DYNAMIC_FTRACE */
  55 #endif /* __ASSEMBLY__ */
  56 #endif /* CONFIG_FUNCTION_TRACER */
  57
  58 #endif /* _ASM_X86_FTRACE_H */