Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * Copyright (C) 2009, 2010 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
3 *
4 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation;
8 * version 2.1 of the License (not later!)
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this program; if not, see <http://www.gnu.org/licenses>
17 *
18 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
19 */
20#include <stdio.h>
21#include <stdlib.h>
22#include <string.h>
23
24#include "event-parse.h"
25#include "event-utils.h"
26#include "trace-seq.h"
27
28static struct func_stack {
29 int size;
30 char **stack;
31} *fstack;
32
33static int cpus = -1;
34
35#define STK_BLK 10
36
37struct tep_plugin_option plugin_options[] =
38{
39 {
40 .name = "parent",
41 .plugin_alias = "ftrace",
42 .description =
43 "Print parent of functions for function events",
44 },
45 {
46 .name = "indent",
47 .plugin_alias = "ftrace",
48 .description =
49 "Try to show function call indents, based on parents",
50 .set = 1,
51 },
52 {
53 .name = NULL,
54 }
55};
56
57static struct tep_plugin_option *ftrace_parent = &plugin_options[0];
58static struct tep_plugin_option *ftrace_indent = &plugin_options[1];
59
60static void add_child(struct func_stack *stack, const char *child, int pos)
61{
62 int i;
63
64 if (!child)
65 return;
66
67 if (pos < stack->size)
68 free(stack->stack[pos]);
69 else {
70 char **ptr;
71
72 ptr = realloc(stack->stack, sizeof(char *) *
73 (stack->size + STK_BLK));
74 if (!ptr) {
75 warning("could not allocate plugin memory\n");
76 return;
77 }
78
79 stack->stack = ptr;
80
81 for (i = stack->size; i < stack->size + STK_BLK; i++)
82 stack->stack[i] = NULL;
83 stack->size += STK_BLK;
84 }
85
86 stack->stack[pos] = strdup(child);
87}
88
89static int add_and_get_index(const char *parent, const char *child, int cpu)
90{
91 int i;
92
93 if (cpu < 0)
94 return 0;
95
96 if (cpu > cpus) {
97 struct func_stack *ptr;
98
99 ptr = realloc(fstack, sizeof(*fstack) * (cpu + 1));
100 if (!ptr) {
101 warning("could not allocate plugin memory\n");
102 return 0;
103 }
104
105 fstack = ptr;
106
107 /* Account for holes in the cpu count */
108 for (i = cpus + 1; i <= cpu; i++)
109 memset(&fstack[i], 0, sizeof(fstack[i]));
110 cpus = cpu;
111 }
112
113 for (i = 0; i < fstack[cpu].size && fstack[cpu].stack[i]; i++) {
114 if (strcmp(parent, fstack[cpu].stack[i]) == 0) {
115 add_child(&fstack[cpu], child, i+1);
116 return i;
117 }
118 }
119
120 /* Not found */
121 add_child(&fstack[cpu], parent, 0);
122 add_child(&fstack[cpu], child, 1);
123 return 0;
124}
125
126static int function_handler(struct trace_seq *s, struct tep_record *record,
127 struct tep_event *event, void *context)
128{
129 struct tep_handle *tep = event->tep;
130 unsigned long long function;
131 unsigned long long pfunction;
132 const char *func;
133 const char *parent;
134 int index = 0;
135
136 if (tep_get_field_val(s, event, "ip", record, &function, 1))
137 return trace_seq_putc(s, '!');
138
139 func = tep_find_function(tep, function);
140
141 if (tep_get_field_val(s, event, "parent_ip", record, &pfunction, 1))
142 return trace_seq_putc(s, '!');
143
144 parent = tep_find_function(tep, pfunction);
145
146 if (parent && ftrace_indent->set)
147 index = add_and_get_index(parent, func, record->cpu);
148
149 trace_seq_printf(s, "%*s", index*3, "");
150
151 if (func)
152 trace_seq_printf(s, "%s", func);
153 else
154 trace_seq_printf(s, "0x%llx", function);
155
156 if (ftrace_parent->set) {
157 trace_seq_printf(s, " <-- ");
158 if (parent)
159 trace_seq_printf(s, "%s", parent);
160 else
161 trace_seq_printf(s, "0x%llx", pfunction);
162 }
163
164 return 0;
165}
166
167int TEP_PLUGIN_LOADER(struct tep_handle *tep)
168{
169 tep_register_event_handler(tep, -1, "ftrace", "function",
170 function_handler, NULL);
171
172 tep_plugin_add_options("ftrace", plugin_options);
173
174 return 0;
175}
176
177void TEP_PLUGIN_UNLOADER(struct tep_handle *tep)
178{
179 int i, x;
180
181 tep_unregister_event_handler(tep, -1, "ftrace", "function",
182 function_handler, NULL);
183
184 for (i = 0; i <= cpus; i++) {
185 for (x = 0; x < fstack[i].size && fstack[i].stack[x]; x++)
186 free(fstack[i].stack[x]);
187 free(fstack[i].stack);
188 }
189
190 tep_plugin_remove_options(plugin_options);
191
192 free(fstack);
193 fstack = NULL;
194 cpus = -1;
195}