1 /* 2 * arch/arm64/include/asm/ftrace.h 3 * 4 * Copyright (C) 2013 Linaro Limited 5 * Author: AKASHI Takahiro <takahiro.akashi@linaro.org> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 #ifndef __ASM_FTRACE_H 12 #define __ASM_FTRACE_H 13 14 #include <asm/insn.h> 15 16 #define MCOUNT_ADDR ((unsigned long)_mcount) 17 #define MCOUNT_INSN_SIZE AARCH64_INSN_SIZE 18 19 #ifndef __ASSEMBLY__ 20 #include <linux/compat.h> 21 22 extern void _mcount(unsigned long); 23 extern void *return_address(unsigned int); 24 25 struct dyn_arch_ftrace { 26 /* No extra data needed for arm64 */ 27 }; 28 29 extern unsigned long ftrace_graph_call; 30 31 extern void return_to_handler(void); 32 33 static inline unsigned long ftrace_call_adjust(unsigned long addr) 34 { 35 /* 36 * addr is the address of the mcount call instruction. 37 * recordmcount does the necessary offset calculation. 38 */ 39 return addr; 40 } 41 42 #define ftrace_return_address(n) return_address(n) 43 44 /* 45 * Because AArch32 mode does not share the same syscall table with AArch64, 46 * tracing compat syscalls may result in reporting bogus syscalls or even 47 * hang-up, so just do not trace them. 48 * See kernel/trace/trace_syscalls.c 49 * 50 * x86 code says: 51 * If the user really wants these, then they should use the 52 * raw syscall tracepoints with filtering. 53 */ 54 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 55 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) 56 { 57 return is_compat_task(); 58 } 59 60 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME 61 62 static inline bool arch_syscall_match_sym_name(const char *sym, 63 const char *name) 64 { 65 /* 66 * Since all syscall functions have __arm64_ prefix, we must skip it. 67 * However, as we described above, we decided to ignore compat 68 * syscalls, so we don't care about __arm64_compat_ prefix here. 69 */ 70 return !strcmp(sym + 8, name); 71 } 72 #endif /* ifndef __ASSEMBLY__ */ 73 74 #endif /* __ASM_FTRACE_H */ 75