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 7 #ifdef CC_USING_HOTPATCH 8 #define MCOUNT_INSN_SIZE 6 9 #else 10 #define MCOUNT_INSN_SIZE 24 11 #define MCOUNT_RETURN_FIXUP 18 12 #endif 13 14 #ifndef __ASSEMBLY__ 15 16 #define ftrace_return_address(n) __builtin_return_address(n) 17 18 void _mcount(void); 19 void ftrace_caller(void); 20 21 extern char ftrace_graph_caller_end; 22 extern unsigned long ftrace_plt; 23 24 struct dyn_arch_ftrace { }; 25 26 #define MCOUNT_ADDR ((unsigned long)_mcount) 27 #define FTRACE_ADDR ((unsigned long)ftrace_caller) 28 29 #define KPROBE_ON_FTRACE_NOP 0 30 #define KPROBE_ON_FTRACE_CALL 1 31 32 static inline unsigned long ftrace_call_adjust(unsigned long addr) 33 { 34 return addr; 35 } 36 37 struct ftrace_insn { 38 u16 opc; 39 s32 disp; 40 } __packed; 41 42 static inline void ftrace_generate_nop_insn(struct ftrace_insn *insn) 43 { 44 #ifdef CONFIG_FUNCTION_TRACER 45 #ifdef CC_USING_HOTPATCH 46 /* brcl 0,0 */ 47 insn->opc = 0xc004; 48 insn->disp = 0; 49 #else 50 /* jg .+24 */ 51 insn->opc = 0xc0f4; 52 insn->disp = MCOUNT_INSN_SIZE / 2; 53 #endif 54 #endif 55 } 56 57 static inline int is_ftrace_nop(struct ftrace_insn *insn) 58 { 59 #ifdef CONFIG_FUNCTION_TRACER 60 #ifdef CC_USING_HOTPATCH 61 if (insn->disp == 0) 62 return 1; 63 #else 64 if (insn->disp == MCOUNT_INSN_SIZE / 2) 65 return 1; 66 #endif 67 #endif 68 return 0; 69 } 70 71 static inline void ftrace_generate_call_insn(struct ftrace_insn *insn, 72 unsigned long ip) 73 { 74 #ifdef CONFIG_FUNCTION_TRACER 75 unsigned long target; 76 77 /* brasl r0,ftrace_caller */ 78 target = is_module_addr((void *) ip) ? ftrace_plt : FTRACE_ADDR; 79 insn->opc = 0xc005; 80 insn->disp = (target - ip) / 2; 81 #endif 82 } 83 84 #endif /* __ASSEMBLY__ */ 85 #endif /* _ASM_S390_FTRACE_H */ 86