subr_stack.c revision 159022 
1/*-
2 * Copyright (c) 2005 Antoine Brodin
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/kern/subr_stack.c 159022 2006-05-28 22:15:28Z kris $");
29
30#include <sys/param.h>
31#include <sys/kernel.h>
32#ifdef KTR
33#include <sys/ktr.h>
34#endif
35#include <sys/linker.h>
36#include <sys/malloc.h>
37#include <sys/sbuf.h>
38#include <sys/stack.h>
39#include <sys/systm.h>
40
41MALLOC_DEFINE(M_STACK, "stack", "Stack Traces");
42
43static void stack_symbol(vm_offset_t pc, const char **name, long *offset);
44
45struct stack *
46stack_create(void)
47{
48	struct stack *st;
49
50	st = malloc(sizeof *st, M_STACK, M_WAITOK | M_ZERO);
51	return (st);
52}
53
54void
55stack_destroy(struct stack *st)
56{
57
58	free(st, M_STACK);
59}
60
61int
62stack_put(struct stack *st, vm_offset_t pc)
63{
64
65	if (st->depth < STACK_MAX) {
66		st->pcs[st->depth++] = pc;
67		return (0);
68	} else
69		return (-1);
70}
71
72void
73stack_copy(struct stack *src, struct stack *dst)
74{
75
76	*dst = *src;
77}
78
79void
80stack_zero(struct stack *st)
81{
82
83	bzero(st, sizeof *st);
84}
85
86void
87stack_print(struct stack *st)
88{
89	const char *name;
90	long offset;
91	int i;
92
93	KASSERT(st->depth <= STACK_MAX, ("bogus stack"));
94	for (i = 0; i < st->depth; i++) {
95		stack_symbol(st->pcs[i], &name, &offset);
96		printf("#%d %p at %s+%#lx\n", i, (void *)st->pcs[i],
97		    name, offset);
98	}
99}
100
101void
102stack_sbuf_print(struct sbuf *sb, struct stack *st)
103{
104	const char *name;
105	long offset;
106	int i;
107
108	KASSERT(st->depth <= STACK_MAX, ("bogus stack"));
109	for (i = 0; i < st->depth; i++) {
110		stack_symbol(st->pcs[i], &name, &offset);
111		sbuf_printf(sb, "#%d %p at %s+%#lx\n", i, (void *)st->pcs[i],
112		    name, offset);
113	}
114}
115
116#ifdef KTR
117void
118stack_ktr(u_int mask, const char *file, int line, struct stack *st, u_int depth,
119    int cheap)
120{
121	const char *name;
122	long offset;
123	int i;
124
125	KASSERT(st->depth <= STACK_MAX, ("bogus stack"));
126	if (cheap) {
127		ktr_tracepoint(mask, file, line, "#0 %p %p %p %p %p %p",
128		    st->pcs[0], st->pcs[1], st->pcs[2], st->pcs[3],
129		    st->pcs[4], st->pcs[5]);
130		if (st->depth <= 6)
131			return;
132		ktr_tracepoint(mask, file, line, "#1 %p %p %p %p %p %p",
133		    st->pcs[6], st->pcs[7], st->pcs[8], st->pcs[9],
134		    st->pcs[10], st->pcs[11]);
135		if (st->depth <= 12)
136			return;
137		ktr_tracepoint(mask, file, line, "#2 %p %p %p %p %p %p",
138		    st->pcs[12], st->pcs[13], st->pcs[14], st->pcs[15],
139		    st->pcs[16], st->pcs[17]);
140	} else {
141		if (depth == 0 || st->depth < depth)
142			depth = st->depth;
143		for (i = 0; i < depth; i++) {
144			stack_symbol(st->pcs[i], &name, &offset);
145			ktr_tracepoint(mask, file, line, "#%d %p at %s+%#lx",
146			    i, st->pcs[i], (u_long)name, offset, 0, 0);
147		}
148	}
149}
150#endif
151
152static void
153stack_symbol(vm_offset_t pc, const char **name, long *offset)
154{
155	linker_symval_t symval;
156	c_linker_sym_t sym;
157
158	if (linker_ddb_search_symbol((caddr_t)pc, &sym, offset) != 0)
159		goto out;
160	if (linker_ddb_symbol_values(sym, &symval) != 0)
161		goto out;
162	if (symval.name != NULL) {
163		*name = symval.name;
164		return;
165	}
166out:
167	*offset = 0;
168	*name = "Unknown func";
169}
170