| 1 | /* |
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| 2 | * Low-level ftrace handling |
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| 3 | * |
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| 4 | * Copyright (C) 2009 Michal Simek <monstr@monstr.eu> |
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| 5 | * Copyright (C) 2009 PetaLogix |
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| 6 | * |
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| 7 | * This file is subject to the terms and conditions of the GNU General |
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| 8 | * Public License. See the file COPYING in the main directory of this |
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| 9 | * archive for more details. |
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| 10 | */ |
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| 11 | |
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| 12 | #include <linux/linkage.h> |
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| 13 | |
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| 14 | #define NOALIGN_ENTRY(name) .globl name; name: |
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| 15 | |
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| 16 | /* FIXME MS: I think that I don't need to save all regs */ |
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| 17 | #define SAVE_REGS \ |
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| 18 | addik r1, r1, -120; \ |
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| 19 | swi r2, r1, 4; \ |
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| 20 | swi r3, r1, 8; \ |
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| 21 | swi r4, r1, 12; \ |
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| 22 | swi r5, r1, 116; \ |
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| 23 | swi r6, r1, 16; \ |
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| 24 | swi r7, r1, 20; \ |
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| 25 | swi r8, r1, 24; \ |
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| 26 | swi r9, r1, 28; \ |
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| 27 | swi r10, r1, 32; \ |
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| 28 | swi r11, r1, 36; \ |
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| 29 | swi r12, r1, 40; \ |
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| 30 | swi r13, r1, 44; \ |
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| 31 | swi r14, r1, 48; \ |
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| 32 | swi r16, r1, 52; \ |
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| 33 | swi r17, r1, 56; \ |
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| 34 | swi r18, r1, 60; \ |
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| 35 | swi r19, r1, 64; \ |
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| 36 | swi r20, r1, 68; \ |
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| 37 | swi r21, r1, 72; \ |
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| 38 | swi r22, r1, 76; \ |
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| 39 | swi r23, r1, 80; \ |
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| 40 | swi r24, r1, 84; \ |
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| 41 | swi r25, r1, 88; \ |
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| 42 | swi r26, r1, 92; \ |
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| 43 | swi r27, r1, 96; \ |
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| 44 | swi r28, r1, 100; \ |
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| 45 | swi r29, r1, 104; \ |
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| 46 | swi r30, r1, 108; \ |
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| 47 | swi r31, r1, 112; |
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| 48 | |
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| 49 | #define RESTORE_REGS \ |
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| 50 | lwi r2, r1, 4; \ |
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| 51 | lwi r3, r1, 8; \ |
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| 52 | lwi r4, r1, 12; \ |
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| 53 | lwi r5, r1, 116; \ |
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| 54 | lwi r6, r1, 16; \ |
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| 55 | lwi r7, r1, 20; \ |
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| 56 | lwi r8, r1, 24; \ |
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| 57 | lwi r9, r1, 28; \ |
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| 58 | lwi r10, r1, 32; \ |
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| 59 | lwi r11, r1, 36; \ |
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| 60 | lwi r12, r1, 40; \ |
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| 61 | lwi r13, r1, 44; \ |
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| 62 | lwi r14, r1, 48; \ |
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| 63 | lwi r16, r1, 52; \ |
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| 64 | lwi r17, r1, 56; \ |
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| 65 | lwi r18, r1, 60; \ |
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| 66 | lwi r19, r1, 64; \ |
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| 67 | lwi r20, r1, 68; \ |
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| 68 | lwi r21, r1, 72; \ |
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| 69 | lwi r22, r1, 76; \ |
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| 70 | lwi r23, r1, 80; \ |
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| 71 | lwi r24, r1, 84; \ |
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| 72 | lwi r25, r1, 88; \ |
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| 73 | lwi r26, r1, 92; \ |
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| 74 | lwi r27, r1, 96; \ |
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| 75 | lwi r28, r1, 100; \ |
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| 76 | lwi r29, r1, 104; \ |
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| 77 | lwi r30, r1, 108; \ |
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| 78 | lwi r31, r1, 112; \ |
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| 79 | addik r1, r1, 120; |
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| 80 | |
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| 81 | ENTRY(ftrace_stub) |
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| 82 | rtsd r15, 8; |
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| 83 | nop; |
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| 84 | |
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| 85 | ENTRY(_mcount) |
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| 86 | #ifdef CONFIG_DYNAMIC_FTRACE |
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| 87 | ENTRY(ftrace_caller) |
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| 88 | /* MS: It is just barrier which is removed from C code */ |
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| 89 | rtsd r15, 8 |
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| 90 | nop |
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| 91 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
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| 92 | SAVE_REGS |
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| 93 | swi r15, r1, 0; |
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| 94 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
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| 95 | #ifndef CONFIG_DYNAMIC_FTRACE |
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| 96 | lwi r5, r0, ftrace_graph_return; |
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| 97 | addik r6, r0, ftrace_stub; /* asm implementation */ |
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| 98 | cmpu r5, r5, r6; /* ftrace_graph_return != ftrace_stub */ |
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| 99 | beqid r5, end_graph_tracer; |
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| 100 | nop; |
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| 101 | |
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| 102 | lwi r6, r0, ftrace_graph_entry; |
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| 103 | addik r5, r0, ftrace_graph_entry_stub; /* implemented in C */ |
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| 104 | cmpu r5, r5, r6; /* ftrace_graph_entry != ftrace_graph_entry_stub */ |
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| 105 | beqid r5, end_graph_tracer; |
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| 106 | nop; |
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| 107 | #else /* CONFIG_DYNAMIC_FTRACE */ |
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| 108 | NOALIGN_ENTRY(ftrace_call_graph) |
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| 109 | /* MS: jump over graph function - replaced from C code */ |
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| 110 | bri end_graph_tracer |
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| 111 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
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| 112 | addik r5, r1, 120; /* MS: load parent addr */ |
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| 113 | addik r6, r15, 0; /* MS: load current function addr */ |
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| 114 | bralid r15, prepare_ftrace_return; |
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| 115 | nop; |
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| 116 | /* MS: graph was taken that's why - can jump over function trace */ |
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| 117 | brid end; |
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| 118 | nop; |
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| 119 | end_graph_tracer: |
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| 120 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
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| 121 | #ifndef CONFIG_DYNAMIC_FTRACE |
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| 122 | /* MS: test function trace if is taken or not */ |
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| 123 | lwi r20, r0, ftrace_trace_function; |
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| 124 | addik r6, r0, ftrace_stub; |
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| 125 | cmpu r5, r20, r6; /* ftrace_trace_function != ftrace_stub */ |
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| 126 | beqid r5, end; /* MS: not taken -> jump over */ |
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| 127 | nop; |
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| 128 | #else /* CONFIG_DYNAMIC_FTRACE */ |
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| 129 | NOALIGN_ENTRY(ftrace_call) |
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| 130 | /* instruction for setup imm FUNC_part1, addik r20, r0, FUNC_part2 */ |
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| 131 | nop |
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| 132 | nop |
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| 133 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
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| 134 | /* static normal trace */ |
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| 135 | lwi r6, r1, 120; /* MS: load parent addr */ |
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| 136 | addik r5, r15, -4; /* MS: load current function addr */ |
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| 137 | /* MS: here is dependency on previous code */ |
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| 138 | brald r15, r20; /* MS: jump to ftrace handler */ |
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| 139 | nop; |
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| 140 | end: |
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| 141 | lwi r15, r1, 0; |
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| 142 | RESTORE_REGS |
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| 143 | |
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| 144 | rtsd r15, 8; /* MS: jump back */ |
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| 145 | nop; |
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| 146 | |
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| 147 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
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| 148 | ENTRY(return_to_handler) |
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| 149 | nop; /* MS: just barrier for rtsd r15, 8 */ |
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| 150 | nop; |
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| 151 | SAVE_REGS |
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| 152 | swi r15, r1, 0; |
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| 153 | |
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| 154 | /* MS: find out returning address */ |
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| 155 | bralid r15, ftrace_return_to_handler; |
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| 156 | nop; |
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| 157 | |
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| 158 | /* MS: return value from ftrace_return_to_handler is my returning addr |
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| 159 | * must be before restore regs because I have to restore r3 content */ |
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| 160 | addik r15, r3, 0; |
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| 161 | RESTORE_REGS |
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| 162 | |
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| 163 | rtsd r15, 8; /* MS: jump back */ |
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| 164 | nop; |
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| 165 | #endif /* CONFIG_FUNCTION_TRACER */ |
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| 166 | |
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