arch/arm64/include/asm/ftrace.h

   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 #define MCOUNT_ADDR             ((unsigned long)_mcount)
  15 #define MCOUNT_INSN_SIZE        AARCH64_INSN_SIZE
  16
  17 #ifndef __ASSEMBLY__
  18 #include <linux/compat.h>
  19
  20 extern void _mcount(unsigned long);
  21 extern void *return_address(unsigned int);
  22
  23 struct dyn_arch_ftrace {
  24         /* No extra data needed for arm64 */
  25 };
  26
  27 extern unsigned long ftrace_graph_call;
  28
  29 extern void return_to_handler(void);
  30
  31 static inline unsigned long ftrace_call_adjust(unsigned long addr)
  32 {
  33         /*
  34          * addr is the address of the mcount call instruction.
  35          * recordmcount does the necessary offset calculation.
  36          */
  37         return addr;
  38 }
  39
  40 #define ftrace_return_address(n) return_address(n)
  41
  42 /*
  43  * Because AArch32 mode does not share the same syscall table with AArch64,
  44  * tracing compat syscalls may result in reporting bogus syscalls or even
  45  * hang-up, so just do not trace them.
  46  * See kernel/trace/trace_syscalls.c
  47  *
  48  * x86 code says:
  49  * If the user really wants these, then they should use the
  50  * raw syscall tracepoints with filtering.
  51  */
  52 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
  53 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
  54 {
  55         return is_compat_task();
  56 }
  57
  58 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
  59
  60 static inline bool arch_syscall_match_sym_name(const char *sym,
  61                                                const char *name)
  62 {
  63         /*
  64          * Since all syscall functions have __arm64_ prefix, we must skip it.
  65          * However, as we described above, we decided to ignore compat
  66          * syscalls, so we don't care about __arm64_compat_ prefix here.
  67          */
  68         return !strcmp(sym + 8, name);
  69 }
  70 #endif /* ifndef __ASSEMBLY__ */
  71
  72 #endif /* __ASM_FTRACE_H */