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
 13static struct func_stack {
 14	int size;
 15	char **stack;
 16} *fstack;
 17
 18static int cpus = -1;
 19
 20#define STK_BLK 10
 21
 22struct 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
 49static struct tep_plugin_option *ftrace_parent = &plugin_options[0];
 50static struct tep_plugin_option *ftrace_indent = &plugin_options[1];
 51static struct tep_plugin_option *ftrace_offset = &plugin_options[2];
 52
 53static 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
 82static 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
119static 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
131static 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
172static int
173trace_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
210static int
211trace_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
248int 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
264void 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}