1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3 * Copyright (C) 2009, 2010 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
4 */
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <string.h>
8
9 #include "event-parse.h"
10 #include "event-utils.h"
11 #include "trace-seq.h"
12
13 static struct func_stack {
14 int size;
15 char **stack;
16 } *fstack;
17
18 static int cpus = -1;
19
20 #define STK_BLK 10
21
22 struct tep_plugin_option plugin_options[] =
23 {
24 {
25 .name = "parent",
26 .plugin_alias = "ftrace",
27 .description =
28 "Print parent of functions for function events",
29 },
30 {
31 .name = "indent",
32 .plugin_alias = "ftrace",
33 .description =
34 "Try to show function call indents, based on parents",
35 .set = 1,
36 },
37 {
38 .name = "offset",
39 .plugin_alias = "ftrace",
40 .description =
41 "Show function names as well as their offsets",
42 .set = 0,
43 },
44 {
45 .name = NULL,
46 }
47 };
48
49 static struct tep_plugin_option *ftrace_parent = &plugin_options[0];
50 static struct tep_plugin_option *ftrace_indent = &plugin_options[1];
51 static struct tep_plugin_option *ftrace_offset = &plugin_options[2];
52
add_child(struct func_stack * stack,const char * child,int pos)53 static void add_child(struct func_stack *stack, const char *child, int pos)
54 {
55 int i;
56
57 if (!child)
58 return;
59
60 if (pos < stack->size)
61 free(stack->stack[pos]);
62 else {
63 char **ptr;
64
65 ptr = realloc(stack->stack, sizeof(char *) *
66 (stack->size + STK_BLK));
67 if (!ptr) {
68 warning("could not allocate plugin memory\n");
69 return;
70 }
71
72 stack->stack = ptr;
73
74 for (i = stack->size; i < stack->size + STK_BLK; i++)
75 stack->stack[i] = NULL;
76 stack->size += STK_BLK;
77 }
78
79 stack->stack[pos] = strdup(child);
80 }
81
add_and_get_index(const char * parent,const char * child,int cpu)82 static int add_and_get_index(const char *parent, const char *child, int cpu)
83 {
84 int i;
85
86 if (cpu < 0)
87 return 0;
88
89 if (cpu > cpus) {
90 struct func_stack *ptr;
91
92 ptr = realloc(fstack, sizeof(*fstack) * (cpu + 1));
93 if (!ptr) {
94 warning("could not allocate plugin memory\n");
95 return 0;
96 }
97
98 fstack = ptr;
99
100 /* Account for holes in the cpu count */
101 for (i = cpus + 1; i <= cpu; i++)
102 memset(&fstack[i], 0, sizeof(fstack[i]));
103 cpus = cpu;
104 }
105
106 for (i = 0; i < fstack[cpu].size && fstack[cpu].stack[i]; i++) {
107 if (strcmp(parent, fstack[cpu].stack[i]) == 0) {
108 add_child(&fstack[cpu], child, i+1);
109 return i;
110 }
111 }
112
113 /* Not found */
114 add_child(&fstack[cpu], parent, 0);
115 add_child(&fstack[cpu], child, 1);
116 return 0;
117 }
118
show_function(struct trace_seq * s,struct tep_handle * tep,const char * func,unsigned long long function)119 static void show_function(struct trace_seq *s, struct tep_handle *tep,
120 const char *func, unsigned long long function)
121 {
122 unsigned long long offset;
123
124 trace_seq_printf(s, "%s", func);
125 if (ftrace_offset->set) {
126 offset = tep_find_function_address(tep, function);
127 trace_seq_printf(s, "+0x%x ", (int)(function - offset));
128 }
129 }
130
function_handler(struct trace_seq * s,struct tep_record * record,struct tep_event * event,void * context)131 static int function_handler(struct trace_seq *s, struct tep_record *record,
132 struct tep_event *event, void *context)
133 {
134 struct tep_handle *tep = event->tep;
135 unsigned long long function;
136 unsigned long long pfunction;
137 const char *func;
138 const char *parent;
139 int index = 0;
140
141 if (tep_get_field_val(s, event, "ip", record, &function, 1))
142 return trace_seq_putc(s, '!');
143
144 func = tep_find_function(tep, function);
145
146 if (tep_get_field_val(s, event, "parent_ip", record, &pfunction, 1))
147 return trace_seq_putc(s, '!');
148
149 parent = tep_find_function(tep, pfunction);
150
151 if (parent && ftrace_indent->set)
152 index = add_and_get_index(parent, func, record->cpu);
153
154 trace_seq_printf(s, "%*s", index*3, "");
155
156 if (func)
157 show_function(s, tep, func, function);
158 else
159 trace_seq_printf(s, "0x%llx", function);
160
161 if (ftrace_parent->set) {
162 trace_seq_printf(s, " <-- ");
163 if (parent)
164 show_function(s, tep, parent, pfunction);
165 else
166 trace_seq_printf(s, "0x%llx", pfunction);
167 }
168
169 return 0;
170 }
171
172 static int
trace_stack_handler(struct trace_seq * s,struct tep_record * record,struct tep_event * event,void * context)173 trace_stack_handler(struct trace_seq *s, struct tep_record *record,
174 struct tep_event *event, void *context)
175 {
176 struct tep_format_field *field;
177 unsigned long long addr;
178 const char *func;
179 int long_size;
180 void *data = record->data;
181
182 field = tep_find_any_field(event, "caller");
183 if (!field) {
184 trace_seq_printf(s, "<CANT FIND FIELD %s>", "caller");
185 return 0;
186 }
187
188 trace_seq_puts(s, "<stack trace >\n");
189
190 long_size = tep_get_long_size(event->tep);
191
192 for (data += field->offset; data < record->data + record->size;
193 data += long_size) {
194 addr = tep_read_number(event->tep, data, long_size);
195
196 if ((long_size == 8 && addr == (unsigned long long)-1) ||
197 ((int)addr == -1))
198 break;
199
200 func = tep_find_function(event->tep, addr);
201 if (func)
202 trace_seq_printf(s, "=> %s (%llx)\n", func, addr);
203 else
204 trace_seq_printf(s, "=> %llx\n", addr);
205 }
206
207 return 0;
208 }
209
210 static int
trace_raw_data_handler(struct trace_seq * s,struct tep_record * record,struct tep_event * event,void * context)211 trace_raw_data_handler(struct trace_seq *s, struct tep_record *record,
212 struct tep_event *event, void *context)
213 {
214 struct tep_format_field *field;
215 unsigned long long id;
216 int long_size;
217 void *data = record->data;
218
219 if (tep_get_field_val(s, event, "id", record, &id, 1))
220 return trace_seq_putc(s, '!');
221
222 trace_seq_printf(s, "# %llx", id);
223
224 field = tep_find_any_field(event, "buf");
225 if (!field) {
226 trace_seq_printf(s, "<CANT FIND FIELD %s>", "buf");
227 return 0;
228 }
229
230 long_size = tep_get_long_size(event->tep);
231
232 for (data += field->offset; data < record->data + record->size;
233 data += long_size) {
234 int size = sizeof(long);
235 int left = (record->data + record->size) - data;
236 int i;
237
238 if (size > left)
239 size = left;
240
241 for (i = 0; i < size; i++)
242 trace_seq_printf(s, " %02x", *(unsigned char *)(data + i));
243 }
244
245 return 0;
246 }
247
TEP_PLUGIN_LOADER(struct tep_handle * tep)248 int TEP_PLUGIN_LOADER(struct tep_handle *tep)
249 {
250 tep_register_event_handler(tep, -1, "ftrace", "function",
251 function_handler, NULL);
252
253 tep_register_event_handler(tep, -1, "ftrace", "kernel_stack",
254 trace_stack_handler, NULL);
255
256 tep_register_event_handler(tep, -1, "ftrace", "raw_data",
257 trace_raw_data_handler, NULL);
258
259 tep_plugin_add_options("ftrace", plugin_options);
260
261 return 0;
262 }
263
TEP_PLUGIN_UNLOADER(struct tep_handle * tep)264 void TEP_PLUGIN_UNLOADER(struct tep_handle *tep)
265 {
266 int i, x;
267
268 tep_unregister_event_handler(tep, -1, "ftrace", "function",
269 function_handler, NULL);
270
271 for (i = 0; i <= cpus; i++) {
272 for (x = 0; x < fstack[i].size && fstack[i].stack[x]; x++)
273 free(fstack[i].stack[x]);
274 free(fstack[i].stack);
275 }
276
277 tep_plugin_remove_options(plugin_options);
278
279 free(fstack);
280 fstack = NULL;
281 cpus = -1;
282 }
283