subr_stack.c revision 184060
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 "opt_ddb.h" 28 29#include <sys/cdefs.h> 30__FBSDID("$FreeBSD: head/sys/kern/subr_stack.c 184060 2008-10-19 11:13:49Z kib $"); 31 32#include <sys/param.h> 33#include <sys/kernel.h> 34#ifdef KTR 35#include <sys/ktr.h> 36#endif 37#include <sys/linker.h> 38#include <sys/malloc.h> 39#include <sys/sbuf.h> 40#include <sys/stack.h> 41#include <sys/systm.h> 42 43static MALLOC_DEFINE(M_STACK, "stack", "Stack Traces"); 44 45static void stack_symbol(vm_offset_t pc, char *namebuf, u_int buflen, 46 long *offset); 47#ifdef DDB 48static void stack_symbol_ddb(vm_offset_t pc, const char **name, long *offset); 49#endif 50 51struct stack * 52stack_create(void) 53{ 54 struct stack *st; 55 56 st = malloc(sizeof *st, M_STACK, M_WAITOK | M_ZERO); 57 return (st); 58} 59 60void 61stack_destroy(struct stack *st) 62{ 63 64 free(st, M_STACK); 65} 66 67int 68stack_put(struct stack *st, vm_offset_t pc) 69{ 70 71 if (st->depth < STACK_MAX) { 72 st->pcs[st->depth++] = pc; 73 return (0); 74 } else 75 return (-1); 76} 77 78void 79stack_copy(struct stack *src, struct stack *dst) 80{ 81 82 *dst = *src; 83} 84 85void 86stack_zero(struct stack *st) 87{ 88 89 bzero(st, sizeof *st); 90} 91 92void 93stack_print(struct stack *st) 94{ 95 char namebuf[64]; 96 long offset; 97 int i; 98 99 KASSERT(st->depth <= STACK_MAX, ("bogus stack")); 100 for (i = 0; i < st->depth; i++) { 101 stack_symbol(st->pcs[i], namebuf, sizeof(namebuf), &offset); 102 printf("#%d %p at %s+%#lx\n", i, (void *)st->pcs[i], 103 namebuf, offset); 104 } 105} 106 107#ifdef DDB 108void 109stack_print_ddb(struct stack *st) 110{ 111 const char *name; 112 long offset; 113 int i; 114 115 KASSERT(st->depth <= STACK_MAX, ("bogus stack")); 116 for (i = 0; i < st->depth; i++) { 117 stack_symbol_ddb(st->pcs[i], &name, &offset); 118 printf("#%d %p at %s+%#lx\n", i, (void *)st->pcs[i], 119 name, offset); 120 } 121} 122#endif 123 124/* 125 * Two print routines -- one for use from DDB and DDB-like contexts, the 126 * other for use in the live kernel. 127 */ 128void 129stack_sbuf_print(struct sbuf *sb, struct stack *st) 130{ 131 char namebuf[64]; 132 long offset; 133 int i; 134 135 KASSERT(st->depth <= STACK_MAX, ("bogus stack")); 136 for (i = 0; i < st->depth; i++) { 137 stack_symbol(st->pcs[i], namebuf, sizeof(namebuf), &offset); 138 sbuf_printf(sb, "#%d %p at %s+%#lx\n", i, (void *)st->pcs[i], 139 namebuf, offset); 140 } 141} 142 143#ifdef DDB 144void 145stack_sbuf_print_ddb(struct sbuf *sb, struct stack *st) 146{ 147 const char *name; 148 long offset; 149 int i; 150 151 KASSERT(st->depth <= STACK_MAX, ("bogus stack")); 152 for (i = 0; i < st->depth; i++) { 153 stack_symbol_ddb(st->pcs[i], &name, &offset); 154 sbuf_printf(sb, "#%d %p at %s+%#lx\n", i, (void *)st->pcs[i], 155 name, offset); 156 } 157} 158 159#ifdef KTR 160void 161stack_ktr(u_int mask, const char *file, int line, struct stack *st, u_int depth, 162 int cheap) 163{ 164 const char *name; 165 long offset; 166 int i; 167 168 KASSERT(st->depth <= STACK_MAX, ("bogus stack")); 169 if (cheap) { 170 ktr_tracepoint(mask, file, line, "#0 %p %p %p %p %p %p", 171 st->pcs[0], st->pcs[1], st->pcs[2], st->pcs[3], 172 st->pcs[4], st->pcs[5]); 173 if (st->depth <= 6) 174 return; 175 ktr_tracepoint(mask, file, line, "#1 %p %p %p %p %p %p", 176 st->pcs[6], st->pcs[7], st->pcs[8], st->pcs[9], 177 st->pcs[10], st->pcs[11]); 178 if (st->depth <= 12) 179 return; 180 ktr_tracepoint(mask, file, line, "#2 %p %p %p %p %p %p", 181 st->pcs[12], st->pcs[13], st->pcs[14], st->pcs[15], 182 st->pcs[16], st->pcs[17]); 183 } else { 184 if (depth == 0 || st->depth < depth) 185 depth = st->depth; 186 for (i = 0; i < depth; i++) { 187 stack_symbol_ddb(st->pcs[i], &name, &offset); 188 ktr_tracepoint(mask, file, line, "#%d %p at %s+%#lx", 189 i, st->pcs[i], (u_long)name, offset, 0, 0); 190 } 191 } 192} 193#endif 194#endif 195 196/* 197 * Two variants of stack symbol lookup -- one that uses the DDB interfaces 198 * and bypasses linker locking, and the other that doesn't. 199 */ 200static void 201stack_symbol(vm_offset_t pc, char *namebuf, u_int buflen, long *offset) 202{ 203 204 if (linker_search_symbol_name((caddr_t)pc, namebuf, buflen, 205 offset) != 0) { 206 *offset = 0; 207 strlcpy(namebuf, "??", buflen); 208 } 209} 210 211#ifdef DDB 212static void 213stack_symbol_ddb(vm_offset_t pc, const char **name, long *offset) 214{ 215 linker_symval_t symval; 216 c_linker_sym_t sym; 217 218 if (linker_ddb_search_symbol((caddr_t)pc, &sym, offset) != 0) 219 goto out; 220 if (linker_ddb_symbol_values(sym, &symval) != 0) 221 goto out; 222 if (symval.name != NULL) { 223 *name = symval.name; 224 return; 225 } 226 out: 227 *offset = 0; 228 *name = "??"; 229} 230#endif 231