sys/arm/arm/db_trace.c

   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 #include <sys/param.h>
  35 #include <sys/systm.h>
  36
  37 #include <sys/proc.h>
  38 #include <sys/kdb.h>
  39 #include <sys/stack.h>
  40
  41 #include <machine/armreg.h>
  42 #include <machine/asm.h>
  43 #include <machine/cpufunc.h>
  44 #include <machine/db_machdep.h>
  45 #include <machine/debug_monitor.h>
  46 #include <machine/pcb.h>
  47 #include <machine/stack.h>
  48 #include <machine/vmparam.h>
  49
  50 #include <ddb/ddb.h>
  51 #include <ddb/db_access.h>
  52 #include <ddb/db_sym.h>
  53 #include <ddb/db_output.h>
  54
  55 static void
  56 db_stack_trace_cmd(struct unwind_state *state)
  57 {
  58         const char *name;
  59         db_expr_t value;
  60         db_expr_t offset;
  61         c_db_sym_t sym;
  62         u_int reg, i;
  63         char *sep;
  64         uint16_t upd_mask;
  65         bool finished;
  66
  67         finished = false;
  68         while (!finished) {
  69                 finished = unwind_stack_one(state, 1);
  70
  71                 /* Print the frame details */
  72                 sym = db_search_symbol(state->start_pc, DB_STGY_ANY, &offset);
  73                 if (sym == C_DB_SYM_NULL) {
  74                         value = 0;
  75                         name = "(null)";
  76                 } else
  77                         db_symbol_values(sym, &name, &value);
  78                 db_printf("%s() at ", name);
  79                 db_printsym(state->start_pc, DB_STGY_PROC);
  80                 db_printf("\n");
  81                 db_printf("\t pc = 0x%08x  lr = 0x%08x (", state->start_pc,
  82                     state->registers[LR]);
  83                 db_printsym(state->registers[LR], DB_STGY_PROC);
  84                 db_printf(")\n");
  85                 db_printf("\t sp = 0x%08x  fp = 0x%08x",
  86                     state->registers[SP], state->registers[FP]);
  87
  88                 /* Don't print the registers we have already printed */
  89                 upd_mask = state->update_mask &
  90                     ~((1 << SP) | (1 << FP) | (1 << LR) | (1 << PC));
  91                 sep = "\n\t";
  92                 for (i = 0, reg = 0; upd_mask != 0; upd_mask >>= 1, reg++) {
  93                         if ((upd_mask & 1) != 0) {
  94                                 db_printf("%s%sr%d = 0x%08x", sep,
  95                                     (reg < 10) ? " " : "", reg,
  96                                     state->registers[reg]);
  97                                 i++;
  98                                 if (i == 2) {
  99                                         sep = "\n\t";
 100                                         i = 0;
 101                                 } else
 102                                         sep = " ";
 103                         }
 104                 }
 105                 db_printf("\n");
 106
 107                 if (finished)
 108                         break;
 109
 110                 /*
 111                  * Stop if directed to do so, or if we've unwound back to the
 112                  * kernel entry point, or if the unwind function didn't change
 113                  * anything (to avoid getting stuck in this loop forever).
 114                  * If the latter happens, it's an indication that the unwind
 115                  * information is incorrect somehow for the function named in
 116                  * the last frame printed before you see the unwind failure
 117                  * message (maybe it needs a STOP_UNWINDING).
 118                  */
 119                 if (state->registers[PC] < VM_MIN_KERNEL_ADDRESS) {
 120                         db_printf("Unable to unwind into user mode\n");
 121                         finished = true;
 122                 } else if (state->update_mask == 0) {
 123                         db_printf("Unwind failure (no registers changed)\n");
 124                         finished = true;
 125                 }
 126         }
 127 }
 128
 129 void
 130 db_md_list_watchpoints(void)
 131 {
 132
 133         dbg_show_watchpoint();
 134 }
 135
 136 int
 137 db_trace_thread(struct thread *thr, int count)
 138 {
 139         struct unwind_state state;
 140         struct pcb *ctx;
 141
 142         if (thr != curthread) {
 143                 ctx = kdb_thr_ctx(thr);
 144
 145                 state.registers[FP] = ctx->pcb_regs.sf_r11;
 146                 state.registers[SP] = ctx->pcb_regs.sf_sp;
 147                 state.registers[LR] = ctx->pcb_regs.sf_lr;
 148                 state.registers[PC] = ctx->pcb_regs.sf_pc;
 149
 150                 db_stack_trace_cmd(&state);
 151         } else
 152                 db_trace_self();
 153         return (0);
 154 }
 155
 156 void
 157 db_trace_self(void)
 158 {
 159         struct unwind_state state;
 160         uint32_t sp;
 161
 162         /* Read the stack pointer */
 163         __asm __volatile("mov %0, sp" : "=&r" (sp));
 164
 165         state.registers[FP] = (uint32_t)__builtin_frame_address(0);
 166         state.registers[SP] = sp;
 167         state.registers[LR] = (uint32_t)__builtin_return_address(0);
 168         state.registers[PC] = (uint32_t)db_trace_self;
 169
 170         db_stack_trace_cmd(&state);
 171 }