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