sys/riscv/riscv/db_trace.c

   1 /*-
   2  * Copyright (c) 2015 The FreeBSD Foundation
   3  * Copyright (c) 2016 Ruslan Bukin <br@bsdpad.com>
   4  * All rights reserved.
   5  * Copyright (c) 2020 John Baldwin <jhb@FreeBSD.org>
   6  *
   7  * Portions of this software were developed by Semihalf under
   8  * the sponsorship of the FreeBSD Foundation.
   9  *
  10  * Portions of this software were developed by SRI International and the
  11  * University of Cambridge Computer Laboratory under DARPA/AFRL contract
  12  * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
  13  *
  14  * Portions of this software were developed by the University of Cambridge
  15  * Computer Laboratory as part of the CTSRD Project, with support from the
  16  * UK Higher Education Innovation Fund (HEIF).
  17  *
  18  * Redistribution and use in source and binary forms, with or without
  19  * modification, are permitted provided that the following conditions
  20  * are met:
  21  * 1. Redistributions of source code must retain the above copyright
  22  *    notice, this list of conditions and the following disclaimer.
  23  * 2. Redistributions in binary form must reproduce the above copyright
  24  *    notice, this list of conditions and the following disclaimer in the
  25  *    documentation and/or other materials provided with the distribution.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  */
  39
  40 #include <sys/param.h>
  41 #include <sys/kdb.h>
  42 #include <sys/proc.h>
  43
  44 #include <ddb/ddb.h>
  45 #include <ddb/db_sym.h>
  46
  47 #include <machine/pcb.h>
  48 #include <machine/riscvreg.h>
  49 #include <machine/stack.h>
  50 #include <machine/vmparam.h>
  51
  52 void
  53 db_md_list_watchpoints(void)
  54 {
  55
  56 }
  57
  58 static void
  59 db_stack_trace_cmd(struct thread *td, struct unwind_state *frame)
  60 {
  61         const char *name;
  62         db_expr_t offset;
  63         db_expr_t value;
  64         c_db_sym_t sym;
  65         uint64_t pc;
  66
  67         while (1) {
  68                 pc = frame->pc;
  69
  70                 sym = db_search_symbol(pc, DB_STGY_ANY, &offset);
  71                 if (sym == C_DB_SYM_NULL) {
  72                         value = 0;
  73                         name = "(null)";
  74                 } else
  75                         db_symbol_values(sym, &name, &value);
  76
  77                 db_printf("%s() at ", name);
  78                 db_printsym(frame->pc, DB_STGY_PROC);
  79                 db_printf("\n");
  80
  81                 if (strcmp(name, "cpu_exception_handler_supervisor") == 0 ||
  82                     strcmp(name, "cpu_exception_handler_user") == 0) {
  83                         struct trapframe *tf;
  84
  85                         tf = (struct trapframe *)(uintptr_t)frame->sp;
  86                         if (!__is_aligned(tf, _Alignof(*tf)) ||
  87                             !kstack_contains(td, (vm_offset_t)tf,
  88                             sizeof(*tf))) {
  89                                 db_printf("--- invalid trapframe %p\n", tf);
  90                                 break;
  91                         }
  92
  93                         if ((tf->tf_scause & SCAUSE_INTR) != 0) {
  94                                 db_printf("--- interrupt %ld\n",
  95                                     tf->tf_scause & SCAUSE_CODE);
  96                         } else if (tf->tf_scause == SCAUSE_ECALL_USER) {
  97                                 db_printf("--- syscall");
  98                                 db_decode_syscall(td, td->td_sa.code);
  99                                 db_printf("\n");
 100                         } else {
 101                                 db_printf("--- exception %ld, tval = %#lx\n",
 102                                     tf->tf_scause & SCAUSE_CODE,
 103                                     tf->tf_stval);
 104                         }
 105                         frame->sp = tf->tf_sp;
 106                         frame->fp = tf->tf_s[0];
 107                         frame->pc = tf->tf_sepc;
 108                         if (!INKERNEL(frame->fp))
 109                                 break;
 110                         continue;
 111                 }
 112
 113                 if (strcmp(name, "fork_trampoline") == 0)
 114                         break;
 115
 116                 if (!unwind_frame(td, frame))
 117                         break;
 118         }
 119 }
 120
 121 int
 122 db_trace_thread(struct thread *thr, int count)
 123 {
 124         struct unwind_state frame;
 125         struct pcb *ctx;
 126
 127         ctx = kdb_thr_ctx(thr);
 128
 129         frame.sp = ctx->pcb_sp;
 130         frame.fp = ctx->pcb_s[0];
 131         frame.pc = ctx->pcb_ra;
 132         db_stack_trace_cmd(thr, &frame);
 133         return (0);
 134 }
 135
 136 void
 137 db_trace_self(void)
 138 {
 139         struct unwind_state frame;
 140         uintptr_t sp;
 141
 142         __asm __volatile("mv %0, sp" : "=&r" (sp));
 143
 144         frame.sp = sp;
 145         frame.fp = (uintptr_t)__builtin_frame_address(0);
 146         frame.pc = (uintptr_t)db_trace_self;
 147         db_stack_trace_cmd(curthread, &frame);
 148 }