db_trace.c revision 1.21 1 /* $NetBSD: db_trace.c,v 1.21 2002/03/05 15:12:58 simonb Exp $ */
2
3 /*
4 * Mach Operating System
5 * Copyright (c) 1993-1987 Carnegie Mellon University
6 * All Rights Reserved.
7 *
8 * Permission to use, copy, modify and distribute this software and its
9 * documentation is hereby granted, provided that both the copyright
10 * notice and this permission notice appear in all copies of the
11 * software, derivative works or modified versions, and any portions
12 * thereof, and that both notices appear in supporting documentation.
13 *
14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17 *
18 * Carnegie Mellon requests users of this software to return to
19 *
20 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU
21 * School of Computer Science
22 * Carnegie Mellon University
23 * Pittsburgh PA 15213-3890
24 *
25 * any improvements or extensions that they make and grant Carnegie Mellon
26 * the rights to redistribute these changes.
27 */
28
29 #include <sys/types.h>
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/proc.h>
33 #include <sys/user.h>
34
35 #include <mips/mips_opcode.h>
36
37 #include <machine/param.h>
38 #include <machine/db_machdep.h>
39 #include <ddb/db_interface.h>
40 #include <ddb/db_output.h>
41 #include <ddb/db_variables.h>
42 #include <ddb/db_sym.h>
43
44 int __start(void); /* lowest kernel code address */
45 vaddr_t getreg_val(db_expr_t regno);
46
47 #define REG_ARG(i) (4+i)
48 #define SAVES_RA(x) isa_spill((x),31)
49
50 #define KERN_SAVE_REG_IDX(vp) ( \
51 ((vp)->valuep >= (int *)(&((struct mips_saved_state *)0)->s0) && \
52 (vp)->valuep <= (int *)(&((struct mips_saved_state *)0)->s7))? \
53 vp->valuep - (int *)(&((struct mips_saved_state *)0)->s0): \
54 ((vp)->valuep >= (int *)(&((struct mips_saved_state *)0)->sp) && \
55 (vp)->valuep <= (int *)(&((struct mips_saved_state *)0)->ra))? \
56 ((vp)->valuep-(int *)(&((struct mips_saved_state *)0)->sp)) + \
57 ((int *)(&((struct mips_kernel_state *)0)->sp) - (int *)0): \
58 -1)
59
60 db_sym_t localsym(db_sym_t sym, boolean_t isreg, int *lex_level);
61
62 /*
63 * Machine register set.
64 */
65 struct mips_saved_state *db_cur_exc_frame = 0;
66
67 /*XXX*/
68 void stacktrace_subr(int, int, int, int, u_int, u_int, u_int, u_int,
69 void (*)(const char*, ...));
70
71 /*
72 * Stack trace helper.
73 */
74 void db_mips_stack_trace(int, vaddr_t, vaddr_t, vaddr_t, int, vaddr_t);
75 int db_mips_variable_func(const struct db_variable *, db_expr_t *, int);
76
77 #define DB_SETF_REGS db_mips_variable_func
78 #define DBREGS_REG()
79
80 const struct db_variable db_regs[] = {
81 { "at", (long *)&ddb_regs.f_regs[AST], DB_SETF_REGS },
82 { "v0", (long *)&ddb_regs.f_regs[V0], DB_SETF_REGS },
83 { "v1", (long *)&ddb_regs.f_regs[V1], DB_SETF_REGS },
84 { "a0", (long *)&ddb_regs.f_regs[A0], DB_SETF_REGS },
85 { "a1", (long *)&ddb_regs.f_regs[A1], DB_SETF_REGS },
86 { "a2", (long *)&ddb_regs.f_regs[A2], DB_SETF_REGS },
87 { "a3", (long *)&ddb_regs.f_regs[A3], DB_SETF_REGS },
88 { "t0", (long *)&ddb_regs.f_regs[T0], DB_SETF_REGS },
89 { "t1", (long *)&ddb_regs.f_regs[T1], DB_SETF_REGS },
90 { "t2", (long *)&ddb_regs.f_regs[T2], DB_SETF_REGS },
91 { "t3", (long *)&ddb_regs.f_regs[T3], DB_SETF_REGS },
92 { "t4", (long *)&ddb_regs.f_regs[T4], DB_SETF_REGS },
93 { "t5", (long *)&ddb_regs.f_regs[T5], DB_SETF_REGS },
94 { "t6", (long *)&ddb_regs.f_regs[T6], DB_SETF_REGS },
95 { "t7", (long *)&ddb_regs.f_regs[T7], DB_SETF_REGS },
96 { "s0", (long *)&ddb_regs.f_regs[S0], DB_SETF_REGS },
97 { "s1", (long *)&ddb_regs.f_regs[S1], DB_SETF_REGS },
98 { "s2", (long *)&ddb_regs.f_regs[S2], DB_SETF_REGS },
99 { "s3", (long *)&ddb_regs.f_regs[S3], DB_SETF_REGS },
100 { "s4", (long *)&ddb_regs.f_regs[S4], DB_SETF_REGS },
101 { "s5", (long *)&ddb_regs.f_regs[S5], DB_SETF_REGS },
102 { "s6", (long *)&ddb_regs.f_regs[S6], DB_SETF_REGS },
103 { "s7", (long *)&ddb_regs.f_regs[S7], DB_SETF_REGS },
104 { "t8", (long *)&ddb_regs.f_regs[T8], DB_SETF_REGS },
105 { "t9", (long *)&ddb_regs.f_regs[T9], DB_SETF_REGS },
106 { "k0", (long *)&ddb_regs.f_regs[K0], DB_SETF_REGS },
107 { "k1", (long *)&ddb_regs.f_regs[K1], DB_SETF_REGS },
108 { "gp", (long *)&ddb_regs.f_regs[GP], DB_SETF_REGS },
109 { "sp", (long *)&ddb_regs.f_regs[SP], DB_SETF_REGS },
110 { "fp", (long *)&ddb_regs.f_regs[S8], DB_SETF_REGS }, /* frame ptr */
111 { "ra", (long *)&ddb_regs.f_regs[RA], DB_SETF_REGS },
112 { "sr", (long *)&ddb_regs.f_regs[SR], DB_SETF_REGS },
113 { "mdlo",(long *)&ddb_regs.f_regs[MULLO], DB_SETF_REGS },
114 { "mdhi",(long *)&ddb_regs.f_regs[MULHI], DB_SETF_REGS },
115 { "bad", (long *)&ddb_regs.f_regs[BADVADDR], DB_SETF_REGS },
116 { "cs", (long *)&ddb_regs.f_regs[CAUSE], DB_SETF_REGS },
117 { "pc", (long *)&ddb_regs.f_regs[PC], DB_SETF_REGS },
118 };
119 const struct db_variable * const db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]);
120
121 void
122 db_stack_trace_print(db_expr_t addr, boolean_t have_addr, db_expr_t count,
123 char *modif, void (*pr)(const char *, ...))
124 {
125 #ifndef DDB_TRACE
126 struct pcb *pcb;
127 struct proc *p;
128
129 if (!have_addr) {
130 stacktrace_subr(ddb_regs.f_regs[A0], ddb_regs.f_regs[A1],
131 ddb_regs.f_regs[A2], ddb_regs.f_regs[A3],
132 ddb_regs.f_regs[PC],
133 ddb_regs.f_regs[SP],
134 /* non-virtual frame pointer */
135 ddb_regs.f_regs[S8],
136 ddb_regs.f_regs[RA],
137 pr);
138 return;
139 }
140
141 /* "trace/t" */
142 (*pr)("pid %d ", (int)addr);
143 p = pfind(addr);
144 if (p == NULL) {
145 (*pr)("not found\n");
146 return;
147 }
148 if (!(p->p_flag&P_INMEM)) {
149 (*pr)("swapped out\n");
150 return;
151 }
152
153 pcb = &(p->p_addr->u_pcb);
154 (*pr)("at %p\n", pcb);
155
156 stacktrace_subr(0,0,0,0, /* no args known */
157 (int)cpu_switch,
158 pcb->pcb_context[8],
159 pcb->pcb_context[9],
160 pcb->pcb_context[10],
161 pr);
162 #else
163 /*
164 * Incomplete but practically useful stack backtrace.
165 */
166 #define MIPS_JR_RA 0x03e00008 /* instruction code for jr ra */
167 #define MIPS_JR_K0 0x03400008 /* instruction code for jr k0 */
168 #define MIPS_ERET 0x42000018 /* instruction code for eret */
169 unsigned va, pc, ra, sp, func;
170 int insn;
171 InstFmt i;
172 int stacksize;
173 db_addr_t offset;
174 char *name;
175 extern char verylocore[];
176
177 pc = ddb_regs.f_regs[PC];
178 sp = ddb_regs.f_regs[SP];
179 ra = ddb_regs.f_regs[RA];
180 do {
181 va = pc;
182 do {
183 va -= sizeof(int);
184 insn = *(int *)va;
185 if (insn == MIPS_ERET)
186 goto mips3_eret;
187 } while (insn != MIPS_JR_RA && insn != MIPS_JR_K0);
188 va += sizeof(int);
189 mips3_eret:
190 va += sizeof(int);
191 while (*(int *)va == 0x00000000)
192 va += sizeof(int);
193 func = va;
194 stacksize = 0;
195 do {
196 i.word = *(int *)va;
197 if (i.IType.op == OP_SW
198 && i.IType.rs == SP
199 && i.IType.rt == RA)
200 ra = *(int *)(sp + (short)i.IType.imm);
201 if (i.IType.op == OP_ADDIU
202 && i.IType.rs == SP
203 && i.IType.rt == SP)
204 stacksize = -(short)i.IType.imm;
205 va += sizeof(int);
206 } while (va < pc);
207
208 db_find_sym_and_offset(func, &name, &offset);
209 if (name == 0)
210 name = "?";
211 (*pr)("%s()+0x%x, called by %p, stack size %d\n",
212 name, pc - func, (void *)ra, stacksize);
213
214 if (ra == pc) {
215 (*pr)("-- loop? --\n");
216 return;
217 }
218 sp += stacksize;
219 pc = ra;
220 } while (pc > (unsigned)verylocore);
221 if (pc < 0x80000000)
222 (*pr)("-- user process --\n");
223 else
224 (*pr)("-- kernel entry --\n");
225 #endif
226 }
227
228 void
229 db_mips_stack_trace(int count, vaddr_t stackp, vaddr_t the_pc, vaddr_t the_ra,
230 int flags, vaddr_t kstackp)
231 {
232
233 /* nothing... */
234 }
235
236
237 int
238 db_mips_variable_func (const struct db_variable *vp, db_expr_t *valuep,
239 int db_var_fcn)
240 {
241
242 switch (db_var_fcn) {
243 case DB_VAR_GET:
244 *valuep = *(mips_reg_t *) vp->valuep;
245 break;
246 case DB_VAR_SET:
247 *(mips_reg_t *) vp->valuep = *valuep;
248 break;
249 }
250 return 0;
251 }
252