1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_S390_FTRACE_H 3 #define _ASM_S390_FTRACE_H 4 5 #define ARCH_SUPPORTS_FTRACE_OPS 1 6 #define MCOUNT_INSN_SIZE 6 7 8 #ifndef __ASSEMBLY__ 9 #include <asm/stacktrace.h> 10 11 static __always_inline unsigned long return_address(unsigned int n) 12 { 13 struct stack_frame *sf; 14 15 if (!n) 16 return (unsigned long)__builtin_return_address(0); 17 18 sf = (struct stack_frame *)current_frame_address(); 19 do { 20 sf = (struct stack_frame *)sf->back_chain; 21 if (!sf) 22 return 0; 23 } while (--n); 24 return sf->gprs[8]; 25 } 26 #define ftrace_return_address(n) return_address(n) 27 28 void ftrace_caller(void); 29 30 extern void *ftrace_func; 31 32 struct dyn_arch_ftrace { }; 33 34 #define MCOUNT_ADDR 0 35 #define FTRACE_ADDR ((unsigned long)ftrace_caller) 36 37 #define KPROBE_ON_FTRACE_NOP 0 38 #define KPROBE_ON_FTRACE_CALL 1 39 40 struct module; 41 struct dyn_ftrace; 42 struct ftrace_ops; 43 44 bool ftrace_need_init_nop(void); 45 #define ftrace_need_init_nop ftrace_need_init_nop 46 47 int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); 48 #define ftrace_init_nop ftrace_init_nop 49 50 static inline unsigned long ftrace_call_adjust(unsigned long addr) 51 { 52 return addr; 53 } 54 55 #include <linux/ftrace_regs.h> 56 57 static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) 58 { 59 struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs; 60 61 if (test_pt_regs_flag(regs, PIF_FTRACE_FULL_REGS)) 62 return regs; 63 return NULL; 64 } 65 66 static __always_inline void 67 ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, 68 unsigned long ip) 69 { 70 arch_ftrace_regs(fregs)->regs.psw.addr = ip; 71 } 72 73 #undef ftrace_regs_get_frame_pointer 74 static __always_inline unsigned long 75 ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs) 76 { 77 return ftrace_regs_get_stack_pointer(fregs); 78 } 79 80 static __always_inline unsigned long 81 ftrace_regs_get_return_address(const struct ftrace_regs *fregs) 82 { 83 return arch_ftrace_regs(fregs)->regs.gprs[14]; 84 } 85 86 #define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ 87 (_regs)->psw.mask = 0; \ 88 (_regs)->psw.addr = arch_ftrace_regs(fregs)->regs.psw.addr; \ 89 (_regs)->gprs[15] = arch_ftrace_regs(fregs)->regs.gprs[15]; \ 90 } while (0) 91 92 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 93 /* 94 * When an ftrace registered caller is tracing a function that is 95 * also set by a register_ftrace_direct() call, it needs to be 96 * differentiated in the ftrace_caller trampoline. To do this, 97 * place the direct caller in the ORIG_GPR2 part of pt_regs. This 98 * tells the ftrace_caller that there's a direct caller. 99 */ 100 static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs, unsigned long addr) 101 { 102 struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs; 103 regs->orig_gpr2 = addr; 104 } 105 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ 106 107 /* 108 * Even though the system call numbers are identical for s390/s390x a 109 * different system call table is used for compat tasks. This may lead 110 * to e.g. incorrect or missing trace event sysfs files. 111 * Therefore simply do not trace compat system calls at all. 112 * See kernel/trace/trace_syscalls.c. 113 */ 114 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 115 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs) 116 { 117 return is_compat_task(); 118 } 119 120 #define ARCH_HAS_SYSCALL_MATCH_SYM_NAME 121 static inline bool arch_syscall_match_sym_name(const char *sym, 122 const char *name) 123 { 124 /* 125 * Skip __s390_ and __s390x_ prefix - due to compat wrappers 126 * and aliasing some symbols of 64 bit system call functions 127 * may get the __s390_ prefix instead of the __s390x_ prefix. 128 */ 129 return !strcmp(sym + 7, name) || !strcmp(sym + 8, name); 130 } 131 132 void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, 133 struct ftrace_ops *op, struct ftrace_regs *fregs); 134 #define ftrace_graph_func ftrace_graph_func 135 136 #endif /* __ASSEMBLY__ */ 137 138 #ifdef CONFIG_FUNCTION_TRACER 139 140 #define FTRACE_NOP_INSN .word 0xc004, 0x0000, 0x0000 /* brcl 0,0 */ 141 142 #ifndef CC_USING_HOTPATCH 143 144 #define FTRACE_GEN_MCOUNT_RECORD(name) \ 145 .section __mcount_loc, "a", @progbits; \ 146 .quad name; \ 147 .previous; 148 149 #else /* !CC_USING_HOTPATCH */ 150 151 #define FTRACE_GEN_MCOUNT_RECORD(name) 152 153 #endif /* !CC_USING_HOTPATCH */ 154 155 #define FTRACE_GEN_NOP_ASM(name) \ 156 FTRACE_GEN_MCOUNT_RECORD(name) \ 157 FTRACE_NOP_INSN 158 159 #else /* CONFIG_FUNCTION_TRACER */ 160 161 #define FTRACE_GEN_NOP_ASM(name) 162 163 #endif /* CONFIG_FUNCTION_TRACER */ 164 165 #endif /* _ASM_S390_FTRACE_H */ 166