1 /* $NetBSD: db_trace.c,v 1.8 2003/01/17 22:28:48 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 2000, 2001 Ben Harris 5 * Copyright (c) 1996 Scott K. Stevens 6 * 7 * Mach Operating System 8 * Copyright (c) 1991,1990 Carnegie Mellon University 9 * All Rights Reserved. 10 * 11 * Permission to use, copy, modify and distribute this software and its 12 * documentation is hereby granted, provided that both the copyright 13 * notice and this permission notice appear in all copies of the 14 * software, derivative works or modified versions, and any portions 15 * thereof, and that both notices appear in supporting documentation. 16 * 17 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 18 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 19 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 20 * 21 * Carnegie Mellon requests users of this software to return to 22 * 23 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 24 * School of Computer Science 25 * Carnegie Mellon University 26 * Pittsburgh PA 15213-3890 27 * 28 * any improvements or extensions that they make and grant Carnegie the 29 * rights to redistribute these changes. 30 */ 31 #include "opt_ddb.h" 32 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 38 #include <sys/proc.h> 39 #include <sys/kdb.h> 40 #include <sys/stack.h> 41 42 #include <machine/armreg.h> 43 #include <machine/asm.h> 44 #include <machine/cpufunc.h> 45 #include <machine/db_machdep.h> 46 #include <machine/debug_monitor.h> 47 #include <machine/pcb.h> 48 #include <machine/stack.h> 49 #include <machine/vmparam.h> 50 51 #include <ddb/ddb.h> 52 #include <ddb/db_access.h> 53 #include <ddb/db_sym.h> 54 #include <ddb/db_output.h> 55 56 static void 57 db_stack_trace_cmd(struct unwind_state *state) 58 { 59 const char *name; 60 db_expr_t value; 61 db_expr_t offset; 62 c_db_sym_t sym; 63 u_int reg, i; 64 char *sep; 65 uint16_t upd_mask; 66 bool finished; 67 68 finished = false; 69 while (!finished) { 70 finished = unwind_stack_one(state, 1); 71 72 /* Print the frame details */ 73 sym = db_search_symbol(state->start_pc, DB_STGY_ANY, &offset); 74 if (sym == C_DB_SYM_NULL) { 75 value = 0; 76 name = "(null)"; 77 } else 78 db_symbol_values(sym, &name, &value); 79 db_printf("%s() at ", name); 80 db_printsym(state->start_pc, DB_STGY_PROC); 81 db_printf("\n"); 82 db_printf("\t pc = 0x%08x lr = 0x%08x (", state->start_pc, 83 state->registers[LR]); 84 db_printsym(state->registers[LR], DB_STGY_PROC); 85 db_printf(")\n"); 86 db_printf("\t sp = 0x%08x fp = 0x%08x", 87 state->registers[SP], state->registers[FP]); 88 89 /* Don't print the registers we have already printed */ 90 upd_mask = state->update_mask & 91 ~((1 << SP) | (1 << FP) | (1 << LR) | (1 << PC)); 92 sep = "\n\t"; 93 for (i = 0, reg = 0; upd_mask != 0; upd_mask >>= 1, reg++) { 94 if ((upd_mask & 1) != 0) { 95 db_printf("%s%sr%d = 0x%08x", sep, 96 (reg < 10) ? " " : "", reg, 97 state->registers[reg]); 98 i++; 99 if (i == 2) { 100 sep = "\n\t"; 101 i = 0; 102 } else 103 sep = " "; 104 } 105 } 106 db_printf("\n"); 107 108 if (finished) 109 break; 110 111 /* 112 * Stop if directed to do so, or if we've unwound back to the 113 * kernel entry point, or if the unwind function didn't change 114 * anything (to avoid getting stuck in this loop forever). 115 * If the latter happens, it's an indication that the unwind 116 * information is incorrect somehow for the function named in 117 * the last frame printed before you see the unwind failure 118 * message (maybe it needs a STOP_UNWINDING). 119 */ 120 if (state->registers[PC] < VM_MIN_KERNEL_ADDRESS) { 121 db_printf("Unable to unwind into user mode\n"); 122 finished = true; 123 } else if (state->update_mask == 0) { 124 db_printf("Unwind failure (no registers changed)\n"); 125 finished = true; 126 } 127 } 128 } 129 130 void 131 db_md_list_watchpoints(void) 132 { 133 134 dbg_show_watchpoint(); 135 } 136 137 int 138 db_trace_thread(struct thread *thr, int count) 139 { 140 struct unwind_state state; 141 struct pcb *ctx; 142 143 if (thr != curthread) { 144 ctx = kdb_thr_ctx(thr); 145 146 state.registers[FP] = ctx->pcb_regs.sf_r11; 147 state.registers[SP] = ctx->pcb_regs.sf_sp; 148 state.registers[LR] = ctx->pcb_regs.sf_lr; 149 state.registers[PC] = ctx->pcb_regs.sf_pc; 150 151 db_stack_trace_cmd(&state); 152 } else 153 db_trace_self(); 154 return (0); 155 } 156 157 void 158 db_trace_self(void) 159 { 160 struct unwind_state state; 161 uint32_t sp; 162 163 /* Read the stack pointer */ 164 __asm __volatile("mov %0, sp" : "=&r" (sp)); 165 166 state.registers[FP] = (uint32_t)__builtin_frame_address(0); 167 state.registers[SP] = sp; 168 state.registers[LR] = (uint32_t)__builtin_return_address(0); 169 state.registers[PC] = (uint32_t)db_trace_self; 170 171 db_stack_trace_cmd(&state); 172 } 173