db_trace.c revision 1.43 1 /* $NetBSD: db_trace.c,v 1.43 2015/06/06 22:19:07 matt 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/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: db_trace.c,v 1.43 2015/06/06 22:19:07 matt Exp $");
31
32 #include "opt_ddb.h"
33
34 #include <sys/types.h>
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/proc.h>
38 #include <sys/cpu.h>
39
40 #include <mips/mips_opcode.h>
41
42 #include <machine/db_machdep.h>
43
44 #include <ddb/db_interface.h>
45 #include <ddb/db_output.h>
46 #include <ddb/db_variables.h>
47 #include <ddb/db_sym.h>
48
49 int __start(void); /* lowest kernel code address */
50 vaddr_t getreg_val(db_expr_t regno);
51
52 #define REG_ARG(i) (4+i)
53 #define SAVES_RA(x) isa_spill((x),31)
54
55 #define KERN_SAVE_REG_IDX(vp) ( \
56 ((vp)->valuep >= (int *)(&((struct mips_saved_state *)0)->s0) && \
57 (vp)->valuep <= (int *)(&((struct mips_saved_state *)0)->s7))? \
58 vp->valuep - (int *)(&((struct mips_saved_state *)0)->s0): \
59 ((vp)->valuep >= (int *)(&((struct mips_saved_state *)0)->sp) && \
60 (vp)->valuep <= (int *)(&((struct mips_saved_state *)0)->ra))? \
61 ((vp)->valuep-(int *)(&((struct mips_saved_state *)0)->sp)) + \
62 ((int *)(&((struct mips_kernel_state *)0)->sp) - (int *)0): \
63 -1)
64
65 db_sym_t localsym(db_sym_t sym, bool isreg, int *lex_level);
66
67 /*
68 * Machine register set.
69 */
70 struct mips_saved_state *db_cur_exc_frame = 0;
71
72 /*XXX*/
73 void stacktrace_subr(mips_reg_t, mips_reg_t, mips_reg_t, mips_reg_t,
74 vaddr_t, vaddr_t, vaddr_t, vaddr_t,
75 void (*)(const char*, ...));
76
77 /*
78 * Stack trace helper.
79 */
80 void db_mips_stack_trace(int, vaddr_t, vaddr_t, vaddr_t, int, vaddr_t);
81 int db_mips_variable_func(const struct db_variable *, db_expr_t *, int);
82
83 #define DB_SETF_REGS db_mips_variable_func
84 #define DBREGS_REG()
85
86 const struct db_variable db_regs[] = {
87 { "at", (long *)&ddb_regs.r_regs[_R_AST], DB_SETF_REGS },
88 { "v0", (long *)&ddb_regs.r_regs[_R_V0], DB_SETF_REGS },
89 { "v1", (long *)&ddb_regs.r_regs[_R_V1], DB_SETF_REGS },
90 { "a0", (long *)&ddb_regs.r_regs[_R_A0], DB_SETF_REGS },
91 { "a1", (long *)&ddb_regs.r_regs[_R_A1], DB_SETF_REGS },
92 { "a2", (long *)&ddb_regs.r_regs[_R_A2], DB_SETF_REGS },
93 { "a3", (long *)&ddb_regs.r_regs[_R_A3], DB_SETF_REGS },
94 #if defined(__mips_n32) || defined(__mips_n64)
95 { "a4", (long *)&ddb_regs.r_regs[_R_A4], DB_SETF_REGS },
96 { "a5", (long *)&ddb_regs.r_regs[_R_A5], DB_SETF_REGS },
97 { "a6", (long *)&ddb_regs.r_regs[_R_A6], DB_SETF_REGS },
98 { "a7", (long *)&ddb_regs.r_regs[_R_A7], DB_SETF_REGS },
99 { "t0", (long *)&ddb_regs.r_regs[_R_T0], DB_SETF_REGS },
100 { "t1", (long *)&ddb_regs.r_regs[_R_T1], DB_SETF_REGS },
101 { "t2", (long *)&ddb_regs.r_regs[_R_T2], DB_SETF_REGS },
102 { "t3", (long *)&ddb_regs.r_regs[_R_T3], DB_SETF_REGS },
103 #else
104 { "t0", (long *)&ddb_regs.r_regs[_R_T0], DB_SETF_REGS },
105 { "t1", (long *)&ddb_regs.r_regs[_R_T1], DB_SETF_REGS },
106 { "t2", (long *)&ddb_regs.r_regs[_R_T2], DB_SETF_REGS },
107 { "t3", (long *)&ddb_regs.r_regs[_R_T3], DB_SETF_REGS },
108 { "t4", (long *)&ddb_regs.r_regs[_R_T4], DB_SETF_REGS },
109 { "t5", (long *)&ddb_regs.r_regs[_R_T5], DB_SETF_REGS },
110 { "t6", (long *)&ddb_regs.r_regs[_R_T6], DB_SETF_REGS },
111 { "t7", (long *)&ddb_regs.r_regs[_R_T7], DB_SETF_REGS },
112 #endif /* __mips_n32 || __mips_n64 */
113 { "s0", (long *)&ddb_regs.r_regs[_R_S0], DB_SETF_REGS },
114 { "s1", (long *)&ddb_regs.r_regs[_R_S1], DB_SETF_REGS },
115 { "s2", (long *)&ddb_regs.r_regs[_R_S2], DB_SETF_REGS },
116 { "s3", (long *)&ddb_regs.r_regs[_R_S3], DB_SETF_REGS },
117 { "s4", (long *)&ddb_regs.r_regs[_R_S4], DB_SETF_REGS },
118 { "s5", (long *)&ddb_regs.r_regs[_R_S5], DB_SETF_REGS },
119 { "s6", (long *)&ddb_regs.r_regs[_R_S6], DB_SETF_REGS },
120 { "s7", (long *)&ddb_regs.r_regs[_R_S7], DB_SETF_REGS },
121 { "t8", (long *)&ddb_regs.r_regs[_R_T8], DB_SETF_REGS },
122 { "t9", (long *)&ddb_regs.r_regs[_R_T9], DB_SETF_REGS },
123 { "k0", (long *)&ddb_regs.r_regs[_R_K0], DB_SETF_REGS },
124 { "k1", (long *)&ddb_regs.r_regs[_R_K1], DB_SETF_REGS },
125 { "gp", (long *)&ddb_regs.r_regs[_R_GP], DB_SETF_REGS },
126 { "sp", (long *)&ddb_regs.r_regs[_R_SP], DB_SETF_REGS },
127 { "fp", (long *)&ddb_regs.r_regs[_R_S8], DB_SETF_REGS },/* frame ptr */
128 { "ra", (long *)&ddb_regs.r_regs[_R_RA], DB_SETF_REGS },
129 { "sr", (long *)&ddb_regs.r_regs[_R_SR], DB_SETF_REGS },
130 { "mdlo",(long *)&ddb_regs.r_regs[_R_MULLO], DB_SETF_REGS },
131 { "mdhi",(long *)&ddb_regs.r_regs[_R_MULHI], DB_SETF_REGS },
132 { "bad", (long *)&ddb_regs.r_regs[_R_BADVADDR], DB_SETF_REGS },
133 { "cs", (long *)&ddb_regs.r_regs[_R_CAUSE], DB_SETF_REGS },
134 { "pc", (long *)&ddb_regs.r_regs[_R_PC], DB_SETF_REGS },
135 };
136 const struct db_variable * const db_eregs = db_regs + __arraycount(db_regs);
137
138 void
139 db_stack_trace_print(db_expr_t addr, bool have_addr, db_expr_t count,
140 const char *modif, void (*pr)(const char *, ...))
141 {
142 #ifndef DDB_TRACE
143 struct pcb *pcb;
144 struct proc *p;
145 struct lwp *l;
146 const char *cp = modif;
147 char c;
148 bool lwpaddr = false;
149
150 if (!have_addr) {
151 struct reg * regs = &ddb_regs;
152 stacktrace_subr(regs->r_regs[_R_A0],
153 regs->r_regs[_R_A1],
154 regs->r_regs[_R_A2],
155 regs->r_regs[_R_A3],
156 regs->r_regs[_R_PC],
157 regs->r_regs[_R_SP],
158 /* non-virtual frame pointer */
159 regs->r_regs[_R_S8],
160 regs->r_regs[_R_RA],
161 pr);
162 return;
163 }
164
165 while ((c = *cp++) != 0) {
166 if (c == 'a') {
167 lwpaddr = true;
168 }
169 }
170
171 if (lwpaddr) {
172 l = (struct lwp *)(intptr_t)addr;
173 (*pr)("pid %d.%d ", l->l_proc->p_pid, l->l_lid);
174 } else {
175 /* "trace/t" */
176
177 (*pr)("pid %d ", (int)addr);
178 p = proc_find_raw(addr);
179 if (p == NULL) {
180 (*pr)("not found\n");
181 return;
182 }
183 l = LIST_FIRST(&p->p_lwps); /* XXX NJWLWP */
184 }
185
186 pcb = lwp_getpcb(l);
187 (*pr)("at %p\n", pcb);
188
189 stacktrace_subr(0,0,0,0, /* no args known */
190 (vaddr_t)cpu_switchto,
191 pcb->pcb_context.val[_L_SP],
192 pcb->pcb_context.val[_L_S8],
193 pcb->pcb_context.val[_L_RA],
194 pr);
195 #else
196 /*
197 * Incomplete but practically useful stack backtrace.
198 */
199 #define MIPS_JR_RA 0x03e00008 /* instruction code for jr ra */
200 #define MIPS_JR_K0 0x03400008 /* instruction code for jr k0 */
201 #define MIPS_ERET 0x42000018 /* instruction code for eret */
202 register_t va, pc, ra, sp, func;
203 int insn;
204 InstFmt i;
205 int stacksize;
206 db_addr_t offset;
207 const char *name;
208 extern char verylocore[];
209
210 pc = ddb_regs.r_regs[_R_PC];
211 sp = ddb_regs.r_regs[_R_SP];
212 ra = ddb_regs.r_regs[_R_RA];
213 do {
214 va = pc;
215 do {
216 va -= sizeof(int);
217 insn = *(int *)(intptr_t)va;
218 if (insn == MIPS_ERET)
219 goto mips3_eret;
220 } while (insn != MIPS_JR_RA && insn != MIPS_JR_K0);
221 va += sizeof(int);
222 mips3_eret:
223 va += sizeof(int);
224 while (*(int *)(intptr_t)va == 0x00000000)
225 va += sizeof(int);
226 func = va;
227 stacksize = 0;
228 do {
229 i.word = *(int *)(intptr_t)va;
230 if (((i.IType.op == OP_SW) || (i.IType.op == OP_SD))
231 && i.IType.rs == _R_SP
232 && i.IType.rt == _R_RA)
233 ra = *(int *)(intptr_t)(sp + (short)i.IType.imm);
234 if (((i.IType.op == OP_ADDIU) || (i.IType.op == OP_DADDIU))
235 && i.IType.rs == _R_SP
236 && i.IType.rt == _R_SP)
237 stacksize = -(short)i.IType.imm;
238 va += sizeof(int);
239 } while (va < pc);
240
241 db_find_sym_and_offset(func, &name, &offset);
242 if (name == 0)
243 name = "?";
244 (*pr)("%s()+0x%x, called by %p, stack size %d\n",
245 name, pc - func, (void *)(intptr_t)ra, stacksize);
246
247 if (ra == pc) {
248 (*pr)("-- loop? --\n");
249 return;
250 }
251 sp += stacksize;
252 pc = ra;
253 } while (pc > (intptr_t)verylocore);
254 if (pc < 0x80000000)
255 (*pr)("-- user process --\n");
256 else
257 (*pr)("-- kernel entry --\n");
258 #endif
259 }
260
261 void
262 db_mips_stack_trace(int count, vaddr_t stackp, vaddr_t the_pc, vaddr_t the_ra,
263 int flags, vaddr_t kstackp)
264 {
265
266 /* nothing... */
267 }
268
269
270 int
271 db_mips_variable_func (const struct db_variable *vp, db_expr_t *valuep,
272 int db_var_fcn)
273 {
274
275 switch (db_var_fcn) {
276 case DB_VAR_GET:
277 *valuep = *(mips_reg_t *) vp->valuep;
278 break;
279 case DB_VAR_SET:
280 *(mips_reg_t *) vp->valuep = *valuep;
281 break;
282 }
283 return 0;
284 }
285