summaryrefslogtreecommitdiff
path: root/tools/lib/traceevent/plugin_function.c
blob: 42dbf73758f3425f20c3401a5c64f024459ddfaf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
/*
 * Copyright (C) 2009, 2010 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License (not later!)
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this program; if not,  see <http://www.gnu.org/licenses>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "event-parse.h"
#include "event-utils.h"

static struct func_stack {
	int size;
	char **stack;
} *fstack;

static int cpus = -1;

#define STK_BLK 10

struct pevent_plugin_option plugin_options[] =
{
	{
		.name = "parent",
		.plugin_alias = "ftrace",
		.description =
		"Print parent of functions for function events",
	},
	{
		.name = "indent",
		.plugin_alias = "ftrace",
		.description =
		"Try to show function call indents, based on parents",
		.set = 1,
	},
	{
		.name = NULL,
	}
};

static struct pevent_plugin_option *ftrace_parent = &plugin_options[0];
static struct pevent_plugin_option *ftrace_indent = &plugin_options[1];

static void add_child(struct func_stack *stack, const char *child, int pos)
{
	int i;

	if (!child)
		return;

	if (pos < stack->size)
		free(stack->stack[pos]);
	else {
		char **ptr;

		ptr = realloc(stack->stack, sizeof(char *) *
			      (stack->size + STK_BLK));
		if (!ptr) {
			warning("could not allocate plugin memory\n");
			return;
		}

		stack->stack = ptr;

		for (i = stack->size; i < stack->size + STK_BLK; i++)
			stack->stack[i] = NULL;
		stack->size += STK_BLK;
	}

	stack->stack[pos] = strdup(child);
}

static int add_and_get_index(const char *parent, const char *child, int cpu)
{
	int i;

	if (cpu < 0)
		return 0;

	if (cpu > cpus) {
		struct func_stack *ptr;

		ptr = realloc(fstack, sizeof(*fstack) * (cpu + 1));
		if (!ptr) {
			warning("could not allocate plugin memory\n");
			return 0;
		}

		fstack = ptr;

		/* Account for holes in the cpu count */
		for (i = cpus + 1; i <= cpu; i++)
			memset(&fstack[i], 0, sizeof(fstack[i]));
		cpus = cpu;
	}

	for (i = 0; i < fstack[cpu].size && fstack[cpu].stack[i]; i++) {
		if (strcmp(parent, fstack[cpu].stack[i]) == 0) {
			add_child(&fstack[cpu], child, i+1);
			return i;
		}
	}

	/* Not found */
	add_child(&fstack[cpu], parent, 0);
	add_child(&fstack[cpu], child, 1);
	return 0;
}

static int function_handler(struct trace_seq *s, struct pevent_record *record,
			    struct event_format *event, void *context)
{
	struct pevent *pevent = event->pevent;
	unsigned long long function;
	unsigned long long pfunction;
	const char *func;
	const char *parent;
	int index = 0;

	if (pevent_get_field_val(s, event, "ip", record, &function, 1))
		return trace_seq_putc(s, '!');

	func = pevent_find_function(pevent, function);

	if (pevent_get_field_val(s, event, "parent_ip", record, &pfunction, 1))
		return trace_seq_putc(s, '!');

	parent = pevent_find_function(pevent, pfunction);

	if (parent && ftrace_indent->set)
		index = add_and_get_index(parent, func, record->cpu);

	trace_seq_printf(s, "%*s", index*3, "");

	if (func)
		trace_seq_printf(s, "%s", func);
	else
		trace_seq_printf(s, "0x%llx", function);

	if (ftrace_parent->set) {
		trace_seq_printf(s, " <-- ");
		if (parent)
			trace_seq_printf(s, "%s", parent);
		else
			trace_seq_printf(s, "0x%llx", pfunction);
	}

	return 0;
}

int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
{
	pevent_register_event_handler(pevent, -1, "ftrace", "function",
				      function_handler, NULL);

	traceevent_plugin_add_options("ftrace", plugin_options);

	return 0;
}

void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
{
	int i, x;

	pevent_unregister_event_handler(pevent, -1, "ftrace", "function",
					function_handler, NULL);

	for (i = 0; i <= cpus; i++) {
		for (x = 0; x < fstack[i].size && fstack[i].stack[x]; x++)
			free(fstack[i].stack[x]);
		free(fstack[i].stack);
	}

	traceevent_plugin_remove_options(plugin_options);

	free(fstack);
	fstack = NULL;
	cpus = -1;
}