1 /* $FreeBSD$ */ 2 /* $NetBSD: db_trace.c,v 1.20 2002/05/13 20:30:09 matt Exp $ */ 3 /* $OpenBSD: db_trace.c,v 1.3 1997/03/21 02:10:48 niklas Exp $ */ 4 5 /* 6 * Mach Operating System 7 * Copyright (c) 1992 Carnegie Mellon University 8 * All Rights Reserved. 9 * 10 * Permission to use, copy, modify and distribute this software and its 11 * documentation is hereby granted, provided that both the copyright 12 * notice and this permission notice appear in all copies of the 13 * software, derivative works or modified versions, and any portions 14 * thereof, and that both notices appear in supporting documentation. 15 * 16 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 17 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 18 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 19 * 20 * Carnegie Mellon requests users of this software to return to 21 * 22 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 23 * School of Computer Science 24 * Carnegie Mellon University 25 * Pittsburgh PA 15213-3890 26 * 27 * any improvements or extensions that they make and grant Carnegie Mellon 28 * the rights to redistribute these changes. 29 */ 30 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/kdb.h> 34 #include <sys/proc.h> 35 #include <sys/user.h> 36 37 #include <vm/vm.h> 38 #include <vm/pmap.h> 39 #include <vm/vm_extern.h> 40 41 #include <machine/db_machdep.h> 42 #include <machine/spr.h> 43 #include <machine/trap.h> 44 45 #include <ddb/ddb.h> 46 #include <ddb/db_access.h> 47 #include <ddb/db_sym.h> 48 #include <ddb/db_variables.h> 49 50 static db_varfcn_t db_frame; 51 52 #define DB_OFFSET(x) (db_expr_t *)offsetof(struct trapframe, x) 53 54 struct db_variable db_regs[] = { 55 { "r0", DB_OFFSET(fixreg[0]), db_frame }, 56 { "r1", DB_OFFSET(fixreg[1]), db_frame }, 57 { "r2", DB_OFFSET(fixreg[2]), db_frame }, 58 { "r3", DB_OFFSET(fixreg[3]), db_frame }, 59 { "r4", DB_OFFSET(fixreg[4]), db_frame }, 60 { "r5", DB_OFFSET(fixreg[5]), db_frame }, 61 { "r6", DB_OFFSET(fixreg[6]), db_frame }, 62 { "r7", DB_OFFSET(fixreg[7]), db_frame }, 63 { "r8", DB_OFFSET(fixreg[8]), db_frame }, 64 { "r9", DB_OFFSET(fixreg[9]), db_frame }, 65 { "r10", DB_OFFSET(fixreg[10]), db_frame }, 66 { "r11", DB_OFFSET(fixreg[11]), db_frame }, 67 { "r12", DB_OFFSET(fixreg[12]), db_frame }, 68 { "r13", DB_OFFSET(fixreg[13]), db_frame }, 69 { "r14", DB_OFFSET(fixreg[14]), db_frame }, 70 { "r15", DB_OFFSET(fixreg[15]), db_frame }, 71 { "r16", DB_OFFSET(fixreg[16]), db_frame }, 72 { "r17", DB_OFFSET(fixreg[17]), db_frame }, 73 { "r18", DB_OFFSET(fixreg[18]), db_frame }, 74 { "r19", DB_OFFSET(fixreg[19]), db_frame }, 75 { "r20", DB_OFFSET(fixreg[20]), db_frame }, 76 { "r21", DB_OFFSET(fixreg[21]), db_frame }, 77 { "r22", DB_OFFSET(fixreg[22]), db_frame }, 78 { "r23", DB_OFFSET(fixreg[23]), db_frame }, 79 { "r24", DB_OFFSET(fixreg[24]), db_frame }, 80 { "r25", DB_OFFSET(fixreg[25]), db_frame }, 81 { "r26", DB_OFFSET(fixreg[26]), db_frame }, 82 { "r27", DB_OFFSET(fixreg[27]), db_frame }, 83 { "r28", DB_OFFSET(fixreg[28]), db_frame }, 84 { "r29", DB_OFFSET(fixreg[29]), db_frame }, 85 { "r30", DB_OFFSET(fixreg[30]), db_frame }, 86 { "r31", DB_OFFSET(fixreg[31]), db_frame }, 87 { "srr0", DB_OFFSET(srr0), db_frame }, 88 { "srr1", DB_OFFSET(srr1), db_frame }, 89 { "lr", DB_OFFSET(lr), db_frame }, 90 { "ctr", DB_OFFSET(ctr), db_frame }, 91 { "cr", DB_OFFSET(cr), db_frame }, 92 { "xer", DB_OFFSET(xer), db_frame }, 93 { "dar", DB_OFFSET(dar), db_frame }, 94 { "dsisr", DB_OFFSET(dsisr), db_frame }, 95 }; 96 struct db_variable *db_eregs = db_regs + sizeof (db_regs)/sizeof (db_regs[0]); 97 98 extern int trapexit[]; 99 extern int end[]; 100 101 /* 102 * register variable handling 103 */ 104 static int 105 db_frame(struct db_variable *vp, db_expr_t *valuep, int op) 106 { 107 uint32_t *reg; 108 109 if (kdb_frame == NULL) 110 return (0); 111 reg = (uint32_t*)((uintptr_t)kdb_frame + (uintptr_t)vp->valuep); 112 if (op == DB_VAR_GET) 113 *valuep = *reg; 114 else 115 *reg = *valuep; 116 return (1); 117 } 118 119 120 /* 121 * Frame tracing. 122 */ 123 static int 124 db_backtrace(struct thread *td, db_addr_t fp, int count) 125 { 126 db_addr_t stackframe, lr, *args; 127 db_expr_t diff; 128 c_db_sym_t sym; 129 const char *symname; 130 boolean_t kernel_only = TRUE; 131 boolean_t full = FALSE; 132 133 #if 0 134 { 135 register char *cp = modif; 136 register char c; 137 138 while ((c = *cp++) != 0) { 139 if (c == 't') 140 trace_thread = TRUE; 141 if (c == 'u') 142 kernel_only = FALSE; 143 if (c == 'f') 144 full = TRUE; 145 } 146 } 147 #endif 148 149 stackframe = fp; 150 151 for (;;) { 152 if (stackframe < PAGE_SIZE) 153 break; 154 155 /* 156 * Locate the next frame by grabbing the backchain ptr 157 * from frame[0] 158 */ 159 stackframe = *(db_addr_t *)stackframe; 160 161 next_frame: 162 /* The saved arg values start at frame[2] */ 163 args = (db_addr_t *)(stackframe + 8); 164 165 if (stackframe < PAGE_SIZE) 166 break; 167 168 if (count-- == 0) 169 break; 170 171 /* 172 * Extract link register from frame and subtract 173 * 4 to convert into calling address (as opposed to 174 * return address) 175 */ 176 lr = *(db_addr_t *)(stackframe + 4) - 4; 177 if ((lr & 3) || (lr < 0x100)) { 178 db_printf("saved LR(0x%x) is invalid.", lr); 179 break; 180 } 181 182 db_printf("0x%08x: ", stackframe); 183 184 /* 185 * The trap code labels the return address from the 186 * call to C code as 'trapexit'. Use this to determine 187 * if the callframe has to traverse a saved trap context 188 */ 189 if (lr + 4 == (db_addr_t) &trapexit) { 190 const char *trapstr; 191 struct trapframe *tf = (struct trapframe *) 192 (stackframe+8); 193 db_printf("%s ", tf->srr1 & PSL_PR ? "user" : "kernel"); 194 switch (tf->exc) { 195 case EXC_DSI: 196 db_printf("DSI %s trap @ %#x by ", 197 tf->dsisr & DSISR_STORE ? "write" : "read", 198 tf->dar); 199 goto print_trap; 200 case EXC_ALI: 201 db_printf("ALI trap @ %#x (DSISR %#x) ", 202 tf->dar, tf->dsisr); 203 goto print_trap; 204 case EXC_ISI: trapstr = "ISI"; break; 205 case EXC_PGM: trapstr = "PGM"; break; 206 case EXC_SC: trapstr = "SC"; break; 207 case EXC_EXI: trapstr = "EXI"; break; 208 case EXC_MCHK: trapstr = "MCHK"; break; 209 case EXC_VEC: trapstr = "VEC"; break; 210 case EXC_FPU: trapstr = "FPU"; break; 211 case EXC_FPA: trapstr = "FPA"; break; 212 case EXC_DECR: trapstr = "DECR"; break; 213 case EXC_BPT: trapstr = "BPT"; break; 214 case EXC_TRC: trapstr = "TRC"; break; 215 case EXC_RUNMODETRC: trapstr = "RUNMODETRC"; break; 216 case EXC_PERF: trapstr = "PERF"; break; 217 case EXC_SMI: trapstr = "SMI"; break; 218 case EXC_RST: trapstr = "RST"; break; 219 default: trapstr = NULL; break; 220 } 221 if (trapstr != NULL) { 222 db_printf("%s trap by ", trapstr); 223 } else { 224 db_printf("trap %#x by ", tf->exc); 225 } 226 227 print_trap: 228 lr = (db_addr_t) tf->srr0; 229 diff = 0; 230 symname = NULL; 231 sym = db_search_symbol(lr, DB_STGY_ANY, &diff); 232 db_symbol_values(sym, &symname, 0); 233 if (symname == NULL || !strcmp(symname, "end")) { 234 db_printf("%#x: srr1=%#x\n", lr, tf->srr1); 235 } else { 236 db_printf("%s+%#x: srr1=%#x\n", symname, diff, 237 tf->srr1); 238 } 239 db_printf("%-10s r1=%#x cr=%#x xer=%#x ctr=%#x", 240 "", tf->fixreg[1], tf->cr, tf->xer, tf->ctr); 241 if (tf->exc == EXC_DSI) 242 db_printf(" dsisr=%#x", tf->dsisr); 243 db_printf("\n"); 244 stackframe = (db_addr_t) tf->fixreg[1]; 245 if (kernel_only && (tf->srr1 & PSL_PR)) 246 break; 247 goto next_frame; 248 } 249 250 diff = 0; 251 symname = NULL; 252 sym = db_search_symbol(lr, DB_STGY_ANY, &diff); 253 db_symbol_values(sym, &symname, 0); 254 if (symname == NULL || !strcmp(symname, "end")) 255 db_printf("at %x", lr); 256 else 257 db_printf("at %s+%#x", symname, diff); 258 if (full) 259 /* Print all the args stored in that stackframe. */ 260 db_printf("(%x, %x, %x, %x, %x, %x, %x, %x)", 261 args[0], args[1], args[2], args[3], 262 args[4], args[5], args[6], args[7]); 263 db_printf("\n"); 264 } 265 266 return (0); 267 } 268 269 void 270 db_stack_trace_cmd(db_expr_t addr, boolean_t have_addr, db_expr_t count, 271 char *modif) 272 { 273 struct thread *td; 274 275 td = (have_addr) ? kdb_thr_lookup(addr) : kdb_thread; 276 if (td == NULL) { 277 db_printf("Thread %d not found\n", (int)addr); 278 return; 279 } 280 db_trace_thread(td, count); 281 } 282 283 void 284 db_trace_self(void) 285 { 286 db_addr_t addr; 287 288 addr = (db_addr_t)__builtin_frame_address(1); 289 db_backtrace(curthread, addr, -1); 290 } 291 292 int 293 db_trace_thread(struct thread *td, int count) 294 { 295 struct pcb *ctx; 296 297 ctx = kdb_thr_ctx(td); 298 return (db_backtrace(td, (db_addr_t)ctx->pcb_sp, count)); 299 } 300 301