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 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 37 38 #include <sys/proc.h> 39 #include <sys/user.h> 40 #include <sys/kdb.h> 41 #include <machine/armreg.h> 42 #include <machine/asm.h> 43 #include <machine/cpufunc.h> 44 #include <machine/db_machdep.h> 45 #include <machine/vmparam.h> 46 #include <ddb/ddb.h> 47 #include <ddb/db_access.h> 48 #include <ddb/db_sym.h> 49 #include <ddb/db_output.h> 50 51 #define INKERNEL(va) (((vm_offset_t)(va)) >= VM_MIN_KERNEL_ADDRESS) 52 53 int db_md_set_watchpoint(db_expr_t addr, db_expr_t size); 54 int db_md_clr_watchpoint(db_expr_t addr, db_expr_t size); 55 void db_md_list_watchpoints(void); 56 /* 57 * APCS stack frames are awkward beasts, so I don't think even trying to use 58 * a structure to represent them is a good idea. 59 * 60 * Here's the diagram from the APCS. Increasing address is _up_ the page. 61 * 62 * save code pointer [fp] <- fp points to here 63 * return link value [fp, #-4] 64 * return sp value [fp, #-8] 65 * return fp value [fp, #-12] 66 * [saved v7 value] 67 * [saved v6 value] 68 * [saved v5 value] 69 * [saved v4 value] 70 * [saved v3 value] 71 * [saved v2 value] 72 * [saved v1 value] 73 * [saved a4 value] 74 * [saved a3 value] 75 * [saved a2 value] 76 * [saved a1 value] 77 * 78 * The save code pointer points twelve bytes beyond the start of the 79 * code sequence (usually a single STM) that created the stack frame. 80 * We have to disassemble it if we want to know which of the optional 81 * fields are actually present. 82 */ 83 84 #define FR_SCP (0) 85 #define FR_RLV (-1) 86 #define FR_RSP (-2) 87 #define FR_RFP (-3) 88 89 static void 90 db_stack_trace_cmd(addr, have_addr, count, modif) 91 db_expr_t addr; 92 int have_addr; 93 db_expr_t count; 94 char *modif; 95 { 96 u_int32_t *frame, *lastframe; 97 c_db_sym_t sym; 98 db_expr_t pc; 99 char c, *cp = modif; 100 const char *name; 101 db_expr_t value; 102 db_expr_t offset; 103 boolean_t kernel_only = TRUE; 104 boolean_t trace_thread = FALSE; 105 int scp_offset; 106 107 if (kdb_frame == NULL && !have_addr) 108 return; 109 while ((c = *cp++) != 0) { 110 if (c == 'u') 111 kernel_only = FALSE; 112 if (c == 't') 113 trace_thread = TRUE; 114 } 115 116 if (!have_addr) 117 frame = (u_int32_t *)(kdb_frame->tf_r11); 118 else { 119 if (trace_thread) { 120 struct proc *p; 121 struct thread *td; 122 pid_t pid = (pid_t)addr; 123 LIST_FOREACH(p, &allproc, p_list) { 124 if (p->p_pid == pid) 125 break; 126 } 127 128 if (p == NULL) { 129 db_printf("not found\n"); 130 return; 131 } 132 if (!(p->p_sflag & PS_INMEM)) { 133 db_printf("swapped out\n"); 134 return; 135 } 136 td = FIRST_THREAD_IN_PROC(p); 137 frame = (u_int32_t *)(td->td_pcb->un_32.pcb32_r11); 138 db_printf("at %p\n", frame); 139 } else 140 frame = (u_int32_t *)(addr); 141 } 142 lastframe = NULL; 143 scp_offset = -(get_pc_str_offset() >> 2); 144 145 while (count-- && frame != NULL) { 146 db_addr_t scp; 147 u_int32_t savecode; 148 int r; 149 u_int32_t *rp; 150 const char *sep; 151 152 /* 153 * In theory, the SCP isn't guaranteed to be in the function 154 * that generated the stack frame. We hope for the best. 155 */ 156 scp = frame[FR_SCP]; 157 158 db_printsym(scp, DB_STGY_PROC); 159 db_printf("\n\t"); 160 pc = kdb_frame->tf_pc; 161 sym = db_search_symbol(pc, DB_STGY_ANY, &offset); 162 if (sym == C_DB_SYM_NULL) { 163 value = 0; 164 name = "(null)"; 165 } else 166 db_symbol_values(sym, &name, &value); 167 db_printf("%s() at ", name); 168 db_printsym(pc, DB_STGY_PROC); 169 db_printf("\n"); 170 #ifdef __PROG26 171 db_printf("scp=0x%08x rlv=0x%08x (", scp, frame[FR_RLV] & R15_PC); 172 db_printsym(frame[FR_RLV] & R15_PC, DB_STGY_PROC); 173 db_printf(")\n"); 174 #else 175 db_printf("scp=0x%08x rlv=0x%08x (", scp, frame[FR_RLV]); 176 db_printsym(frame[FR_RLV], DB_STGY_PROC); 177 db_printf(")\n"); 178 #endif 179 db_printf("\trsp=0x%08x rfp=0x%08x", frame[FR_RSP], frame[FR_RFP]); 180 181 savecode = ((u_int32_t *)scp)[scp_offset]; 182 if ((savecode & 0x0e100000) == 0x08000000) { 183 /* Looks like an STM */ 184 rp = frame - 4; 185 sep = "\n\t"; 186 for (r = 10; r >= 0; r--) { 187 if (savecode & (1 << r)) { 188 db_printf("%sr%d=0x%08x", 189 sep, r, *rp--); 190 sep = (frame - rp) % 4 == 2 ? 191 "\n\t" : " "; 192 } 193 } 194 } 195 196 db_printf("\n"); 197 198 /* 199 * Switch to next frame up 200 */ 201 if (frame[FR_RFP] == 0) 202 break; /* Top of stack */ 203 204 lastframe = frame; 205 frame = (u_int32_t *)(frame[FR_RFP]); 206 207 if (INKERNEL((int)frame)) { 208 /* staying in kernel */ 209 if (frame <= lastframe) { 210 db_printf("Bad frame pointer: %p\n", frame); 211 break; 212 } 213 } else if (INKERNEL((int)lastframe)) { 214 /* switch from user to kernel */ 215 if (kernel_only) 216 break; /* kernel stack only */ 217 } else { 218 /* in user */ 219 if (frame <= lastframe) { 220 db_printf("Bad user frame pointer: %p\n", 221 frame); 222 break; 223 } 224 } 225 } 226 } 227 228 /* XXX stubs */ 229 void 230 db_md_list_watchpoints() 231 { 232 } 233 234 int 235 db_md_clr_watchpoint(db_expr_t addr, db_expr_t size) 236 { 237 return (0); 238 } 239 240 int 241 db_md_set_watchpoint(db_expr_t addr, db_expr_t size) 242 { 243 return (0); 244 } 245 246 int 247 db_trace_thread(struct thread *thr, int count) 248 { 249 uint32_t addr; 250 251 if (thr == curthread) 252 addr = (uint32_t)__builtin_frame_address(0); 253 else 254 addr = thr->td_pcb->un_32.pcb32_r11; 255 db_stack_trace_cmd(addr, 1, -1, NULL); 256 return (0); 257 } 258 259 void 260 db_trace_self(void) 261 { 262 db_trace_thread(curthread, -1); 263 } 264