1 /* SPDX-License-Identifier: GPL-2.0 */ <<
2 /* 1 /*
3 * LoongArch specific _mcount support !! 2 * MIPS specific _mcount support
4 * 3 *
5 * Copyright (C) 2022 Loongson Technology Corp !! 4 * This file is subject to the terms and conditions of the GNU General Public
>> 5 * License. See the file "COPYING" in the main directory of this archive for
>> 6 * more details.
>> 7 *
>> 8 * Copyright (C) 2009 Lemote Inc. & DSLab, Lanzhou University, China
>> 9 * Copyright (C) 2010 DSLab, Lanzhou University, China
>> 10 * Author: Wu Zhangjin <wuzhangjin@gmail.com>
6 */ 11 */
7 12
8 #include <linux/export.h> !! 13 #include <asm/export.h>
9 #include <asm/ftrace.h> <<
10 #include <asm/regdef.h> 14 #include <asm/regdef.h>
11 #include <asm/stackframe.h> 15 #include <asm/stackframe.h>
>> 16 #include <asm/ftrace.h>
12 17
13 .text 18 .text
14 !! 19 .set noreorder
15 #define MCOUNT_S0_OFFSET (0) !! 20 .set noat
16 #define MCOUNT_RA_OFFSET (SZREG) <<
17 #define MCOUNT_STACK_SIZE (2 * SZREG) <<
18 21
19 .macro MCOUNT_SAVE_REGS 22 .macro MCOUNT_SAVE_REGS
20 PTR_ADDI sp, sp, -MCOUNT_STACK_ !! 23 PTR_SUBU sp, PT_SIZE
21 PTR_S s0, sp, MCOUNT_S0_OFFS !! 24 PTR_S ra, PT_R31(sp)
22 PTR_S ra, sp, MCOUNT_RA_OFFS !! 25 PTR_S AT, PT_R1(sp)
23 move s0, a0 !! 26 PTR_S a0, PT_R4(sp)
>> 27 PTR_S a1, PT_R5(sp)
>> 28 PTR_S a2, PT_R6(sp)
>> 29 PTR_S a3, PT_R7(sp)
>> 30 #ifdef CONFIG_64BIT
>> 31 PTR_S a4, PT_R8(sp)
>> 32 PTR_S a5, PT_R9(sp)
>> 33 PTR_S a6, PT_R10(sp)
>> 34 PTR_S a7, PT_R11(sp)
>> 35 #endif
24 .endm 36 .endm
25 37
26 .macro MCOUNT_RESTORE_REGS 38 .macro MCOUNT_RESTORE_REGS
27 move a0, s0 !! 39 PTR_L ra, PT_R31(sp)
28 PTR_L ra, sp, MCOUNT_RA_OFFS !! 40 PTR_L AT, PT_R1(sp)
29 PTR_L s0, sp, MCOUNT_S0_OFFS !! 41 PTR_L a0, PT_R4(sp)
30 PTR_ADDI sp, sp, MCOUNT_STACK_S !! 42 PTR_L a1, PT_R5(sp)
>> 43 PTR_L a2, PT_R6(sp)
>> 44 PTR_L a3, PT_R7(sp)
>> 45 #ifdef CONFIG_64BIT
>> 46 PTR_L a4, PT_R8(sp)
>> 47 PTR_L a5, PT_R9(sp)
>> 48 PTR_L a6, PT_R10(sp)
>> 49 PTR_L a7, PT_R11(sp)
>> 50 #endif
>> 51 PTR_ADDIU sp, PT_SIZE
31 .endm 52 .endm
32 53
33 SYM_FUNC_START(_mcount) !! 54 .macro RETURN_BACK
34 la.pcrel t1, ftrace_stub !! 55 jr ra
35 la.pcrel t2, ftrace_trace_funct !! 56 move ra, AT
36 PTR_L t2, t2, 0 !! 57 .endm
37 beq t1, t2, fgraph_trace <<
38 58
39 MCOUNT_SAVE_REGS !! 59 /*
>> 60 * The -mmcount-ra-address option of gcc 4.5 uses register $12 to pass
>> 61 * the location of the parent's return address.
>> 62 */
>> 63 #define MCOUNT_RA_ADDRESS_REG $12
40 64
41 move a0, ra !! 65 #ifdef CONFIG_DYNAMIC_FTRACE
42 move a1, s0 <<
43 jirl ra, t2, 0 <<
44 66
45 MCOUNT_RESTORE_REGS !! 67 NESTED(ftrace_caller, PT_SIZE, ra)
>> 68 .globl _mcount
>> 69 _mcount:
>> 70 EXPORT_SYMBOL(_mcount)
>> 71 b ftrace_stub
>> 72 #ifdef CONFIG_32BIT
>> 73 addiu sp,sp,8
>> 74 #else
>> 75 nop
>> 76 #endif
46 77
47 fgraph_trace: !! 78 /* When tracing is activated, it calls ftrace_caller+8 (aka here) */
48 #ifdef CONFIG_FUNCTION_GRAPH_TRACER !! 79 MCOUNT_SAVE_REGS
49 la.pcrel t1, ftrace_stub !! 80 #ifdef KBUILD_MCOUNT_RA_ADDRESS
50 la.pcrel t3, ftrace_graph_retur !! 81 PTR_S MCOUNT_RA_ADDRESS_REG, PT_R12(sp)
51 PTR_L t3, t3, 0 !! 82 #endif
52 bne t1, t3, ftrace_graph_c !! 83
53 la.pcrel t1, ftrace_graph_entry !! 84 PTR_SUBU a0, ra, 8 /* arg1: self address */
54 la.pcrel t3, ftrace_graph_entry !! 85 PTR_LA t1, _stext
55 PTR_L t3, t3, 0 !! 86 sltu t2, a0, t1 /* t2 = (a0 < _stext) */
56 bne t1, t3, ftrace_graph_c !! 87 PTR_LA t1, _etext
>> 88 sltu t3, t1, a0 /* t3 = (a0 > _etext) */
>> 89 or t1, t2, t3
>> 90 beqz t1, ftrace_call
>> 91 nop
>> 92 #if defined(KBUILD_MCOUNT_RA_ADDRESS) && defined(CONFIG_32BIT)
>> 93 PTR_SUBU a0, a0, 16 /* arg1: adjust to module's recorded callsite */
>> 94 #else
>> 95 PTR_SUBU a0, a0, 12
57 #endif 96 #endif
58 97
59 SYM_INNER_LABEL(ftrace_stub, SYM_L_GLOBAL) !! 98 .globl ftrace_call
60 jr ra !! 99 ftrace_call:
>> 100 nop /* a placeholder for the call to a real tracing function */
>> 101 move a1, AT /* arg2: parent's return address */
>> 102
61 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 103 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
62 SYM_INNER_LABEL(ftrace_graph_func, SYM_L_GLOBA !! 104 .globl ftrace_graph_call
63 bl ftrace_stub !! 105 ftrace_graph_call:
>> 106 nop
>> 107 nop
64 #endif 108 #endif
65 SYM_FUNC_END(_mcount) !! 109
>> 110 MCOUNT_RESTORE_REGS
>> 111 .globl ftrace_stub
>> 112 ftrace_stub:
>> 113 RETURN_BACK
>> 114 END(ftrace_caller)
>> 115
>> 116 #else /* ! CONFIG_DYNAMIC_FTRACE */
>> 117
>> 118 NESTED(_mcount, PT_SIZE, ra)
66 EXPORT_SYMBOL(_mcount) 119 EXPORT_SYMBOL(_mcount)
>> 120 PTR_LA t1, ftrace_stub
>> 121 PTR_L t2, ftrace_trace_function /* Prepare t2 for (1) */
>> 122 bne t1, t2, static_trace
>> 123 nop
>> 124
>> 125 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
>> 126 PTR_L t3, ftrace_graph_return
>> 127 bne t1, t3, ftrace_graph_caller
>> 128 nop
>> 129 PTR_LA t1, ftrace_graph_entry_stub
>> 130 PTR_L t3, ftrace_graph_entry
>> 131 bne t1, t3, ftrace_graph_caller
>> 132 nop
>> 133 #endif
>> 134 b ftrace_stub
>> 135 #ifdef CONFIG_32BIT
>> 136 addiu sp, sp, 8
>> 137 #else
>> 138 nop
>> 139 #endif
>> 140
>> 141 static_trace:
>> 142 MCOUNT_SAVE_REGS
>> 143
>> 144 move a0, ra /* arg1: self return address */
>> 145 jalr t2 /* (1) call *ftrace_trace_function */
>> 146 move a1, AT /* arg2: parent's return address */
>> 147
>> 148 MCOUNT_RESTORE_REGS
>> 149 #ifdef CONFIG_32BIT
>> 150 addiu sp, sp, 8
>> 151 #endif
>> 152 .globl ftrace_stub
>> 153 ftrace_stub:
>> 154 RETURN_BACK
>> 155 END(_mcount)
>> 156
>> 157 #endif /* ! CONFIG_DYNAMIC_FTRACE */
67 158
68 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 159 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
69 SYM_FUNC_START(ftrace_graph_caller) !! 160
>> 161 NESTED(ftrace_graph_caller, PT_SIZE, ra)
>> 162 #ifndef CONFIG_DYNAMIC_FTRACE
70 MCOUNT_SAVE_REGS 163 MCOUNT_SAVE_REGS
>> 164 #endif
>> 165
>> 166 /* arg1: Get the location of the parent's return address */
>> 167 #ifdef KBUILD_MCOUNT_RA_ADDRESS
>> 168 #ifdef CONFIG_DYNAMIC_FTRACE
>> 169 PTR_L a0, PT_R12(sp)
>> 170 #else
>> 171 move a0, MCOUNT_RA_ADDRESS_REG
>> 172 #endif
>> 173 bnez a0, 1f /* non-leaf func: stored in MCOUNT_RA_ADDRESS_REG */
>> 174 nop
>> 175 #endif
>> 176 PTR_LA a0, PT_R1(sp) /* leaf func: the location in current stack */
>> 177 1:
>> 178
>> 179 /* arg2: Get self return address */
>> 180 #ifdef CONFIG_DYNAMIC_FTRACE
>> 181 PTR_L a1, PT_R31(sp)
>> 182 #else
>> 183 move a1, ra
>> 184 #endif
71 185
72 PTR_ADDI a0, ra, -4 !! 186 /* arg3: Get frame pointer of current stack */
73 PTR_ADDI a1, sp, MCOUNT_STACK_S !! 187 #ifdef CONFIG_64BIT
74 move a2, s0 !! 188 PTR_LA a2, PT_SIZE(sp)
75 bl prepare_ftrace_return !! 189 #else
>> 190 PTR_LA a2, (PT_SIZE+8)(sp)
>> 191 #endif
76 192
>> 193 jal prepare_ftrace_return
>> 194 nop
77 MCOUNT_RESTORE_REGS 195 MCOUNT_RESTORE_REGS
78 jr ra !! 196 #ifndef CONFIG_DYNAMIC_FTRACE
79 SYM_FUNC_END(ftrace_graph_caller) !! 197 #ifdef CONFIG_32BIT
>> 198 addiu sp, sp, 8
>> 199 #endif
>> 200 #endif
>> 201 RETURN_BACK
>> 202 END(ftrace_graph_caller)
80 203
81 SYM_FUNC_START(return_to_handler) !! 204 .align 2
82 PTR_ADDI sp, sp, -FGRET_REGS_SI !! 205 .globl return_to_handler
83 PTR_S a0, sp, FGRET_REGS_A0 !! 206 return_to_handler:
84 PTR_S a1, sp, FGRET_REGS_A1 !! 207 PTR_SUBU sp, PT_SIZE
85 PTR_S zero, sp, FGRET_REGS_F !! 208 PTR_S v0, PT_R2(sp)
86 !! 209
87 move a0, sp !! 210 jal ftrace_return_to_handler
88 bl ftrace_return_to_handl !! 211 PTR_S v1, PT_R3(sp)
89 !! 212
90 /* Restore the real parent address: a0 !! 213 /* restore the real parent address: v0 -> ra */
91 move ra, a0 !! 214 move ra, v0
92 !! 215
93 PTR_L a0, sp, FGRET_REGS_A0 !! 216 PTR_L v0, PT_R2(sp)
94 PTR_L a1, sp, FGRET_REGS_A1 !! 217 PTR_L v1, PT_R3(sp)
95 PTR_ADDI sp, sp, FGRET_REGS_SIZ !! 218 jr ra
96 jr ra !! 219 PTR_ADDIU sp, PT_SIZE
97 SYM_FUNC_END(return_to_handler) <<
98 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ 220 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
>> 221
>> 222 .set at
>> 223 .set reorder
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