1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_S390_FTRACE_H 3 #define _ASM_S390_FTRACE_H 4 5 #define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR 6 #define ARCH_SUPPORTS_FTRACE_OPS 1 7 #define MCOUNT_INSN_SIZE 6 8 9 #ifndef __ASSEMBLY__ 10 11 #ifdef CONFIG_CC_IS_CLANG 12 /* https://bugs.llvm.org/show_bug.cgi?id=41424 */ 13 #define ftrace_return_address(n) 0UL 14 #else 15 #define ftrace_return_address(n) __builtin_return_address(n) 16 #endif 17 18 void ftrace_caller(void); 19 20 extern void *ftrace_func; 21 22 struct dyn_arch_ftrace { }; 23 24 #define MCOUNT_ADDR 0 25 #define FTRACE_ADDR ((unsigned long)ftrace_caller) 26 27 #define KPROBE_ON_FTRACE_NOP 0 28 #define KPROBE_ON_FTRACE_CALL 1 29 30 struct module; 31 struct dyn_ftrace; 32 33 bool ftrace_need_init_nop(void); 34 #define ftrace_need_init_nop ftrace_need_init_nop 35 36 int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); 37 #define ftrace_init_nop ftrace_init_nop 38 39 static inline unsigned long ftrace_call_adjust(unsigned long addr) 40 { 41 return addr; 42 } 43 44 struct ftrace_regs { 45 struct pt_regs regs; 46 }; 47 48 static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) 49 { 50 struct pt_regs *regs = &fregs->regs; 51 52 if (test_pt_regs_flag(regs, PIF_FTRACE_FULL_REGS)) 53 return regs; 54 return NULL; 55 } 56 57 static __always_inline void ftrace_instruction_pointer_set(struct ftrace_regs *fregs, 58 unsigned long ip) 59 { 60 fregs->regs.psw.addr = ip; 61 } 62 63 /* 64 * When an ftrace registered caller is tracing a function that is 65 * also set by a register_ftrace_direct() call, it needs to be 66 * differentiated in the ftrace_caller trampoline. To do this, 67 * place the direct caller in the ORIG_GPR2 part of pt_regs. This 68 * tells the ftrace_caller that there's a direct caller. 69 */ 70 static inline void arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr) 71 { 72 regs->orig_gpr2 = addr; 73 } 74 75 /* 76 * Even though the system call numbers are identical for s390/s390x a 77 * different system call table is used for compat tasks. This may lead 78 * to e.g. incorrect or missing trace event sysfs files. 79 * Therefore simply do not trace compat system calls at all. 80 * See kernel/trace/trace_syscalls.c. 81 */ 82 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 83 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) 84 { 85 return is_compat_task(); 86 } 87 88 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME 89 static inline bool arch_syscall_match_sym_name(const char *sym, 90 const char *name) 91 { 92 /* 93 * Skip __s390_ and __s390x_ prefix - due to compat wrappers 94 * and aliasing some symbols of 64 bit system call functions 95 * may get the __s390_ prefix instead of the __s390x_ prefix. 96 */ 97 return !strcmp(sym + 7, name) || !strcmp(sym + 8, name); 98 } 99 100 #endif /* __ASSEMBLY__ */ 101 102 #ifdef CONFIG_FUNCTION_TRACER 103 104 #define FTRACE_NOP_INSN .word 0xc004, 0x0000, 0x0000 /* brcl 0,0 */ 105 106 #ifndef CC_USING_HOTPATCH 107 108 #define FTRACE_GEN_MCOUNT_RECORD(name) \ 109 .section __mcount_loc, "a", @progbits; \ 110 .quad name; \ 111 .previous; 112 113 #else /* !CC_USING_HOTPATCH */ 114 115 #define FTRACE_GEN_MCOUNT_RECORD(name) 116 117 #endif /* !CC_USING_HOTPATCH */ 118 119 #define FTRACE_GEN_NOP_ASM(name) \ 120 FTRACE_GEN_MCOUNT_RECORD(name) \ 121 FTRACE_NOP_INSN 122 123 #else /* CONFIG_FUNCTION_TRACER */ 124 125 #define FTRACE_GEN_NOP_ASM(name) 126 127 #endif /* CONFIG_FUNCTION_TRACER */ 128 129 #endif /* _ASM_S390_FTRACE_H */ 130