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/cdefs.h>
  41 __FBSDID("$FreeBSD$");
  42
  43 #include <sys/param.h>
  44 #include <sys/kdb.h>
  45 #include <sys/proc.h>
  46
  47 #include <ddb/ddb.h>
  48 #include <ddb/db_sym.h>
  49
  50 #include <machine/pcb.h>
  51 #include <machine/riscvreg.h>
  52 #include <machine/stack.h>
  53 #include <machine/vmparam.h>
  54
  55 void
  56 db_md_list_watchpoints(void)
  57 {
  58
  59 }
  60
  61 static void
  62 db_stack_trace_cmd(struct thread *td, struct unwind_state *frame)
  63 {
  64         const char *name;
  65         db_expr_t offset;
  66         db_expr_t value;
  67         c_db_sym_t sym;
  68         uint64_t pc;
  69
  70         while (1) {
  71                 pc = frame->pc;
  72
  73                 sym = db_search_symbol(pc, DB_STGY_ANY, &offset);
  74                 if (sym == C_DB_SYM_NULL) {
  75                         value = 0;
  76                         name = "(null)";
  77                 } else
  78                         db_symbol_values(sym, &name, &value);
  79
  80                 db_printf("%s() at ", name);
  81                 db_printsym(frame->pc, DB_STGY_PROC);
  82                 db_printf("\n");
  83
  84                 if (strcmp(name, "cpu_exception_handler_supervisor") == 0 ||
  85                     strcmp(name, "cpu_exception_handler_user") == 0) {
  86                         struct trapframe *tf;
  87
  88                         tf = (struct trapframe *)(uintptr_t)frame->sp;
  89                         if (!kstack_contains(td, (vm_offset_t)tf,
  90                             sizeof(*tf))) {
  91                                 db_printf("--- invalid trapframe %p\n", tf);
  92                                 break;
  93                         }
  94
  95                         if ((tf->tf_scause & SCAUSE_INTR) != 0) {
  96                                 db_printf("--- interrupt %ld\n",
  97                                     tf->tf_scause & SCAUSE_CODE);
  98                         } else if (tf->tf_scause == SCAUSE_ECALL_USER) {
  99                                 db_printf("--- syscall");
 100                                 db_decode_syscall(td, td->td_sa.code);
 101                                 db_printf("\n");
 102                         } else {
 103                                 db_printf("--- exception %ld, tval = %#lx\n",
 104                                     tf->tf_scause & SCAUSE_CODE,
 105                                     tf->tf_stval);
 106                         }
 107                         frame->sp = tf->tf_sp;
 108                         frame->fp = tf->tf_s[0];
 109                         frame->pc = tf->tf_sepc;
 110                         if (!INKERNEL(frame->fp))
 111                                 break;
 112                         continue;
 113                 }
 114
 115                 if (strcmp(name, "fork_trampoline") == 0)
 116                         break;
 117
 118                 if (!unwind_frame(td, frame))
 119                         break;
 120         }
 121 }
 122
 123 int
 124 db_trace_thread(struct thread *thr, int count)
 125 {
 126         struct unwind_state frame;
 127         struct pcb *ctx;
 128
 129         ctx = kdb_thr_ctx(thr);
 130
 131         frame.sp = ctx->pcb_sp;
 132         frame.fp = ctx->pcb_s[0];
 133         frame.pc = ctx->pcb_ra;
 134         db_stack_trace_cmd(thr, &frame);
 135         return (0);
 136 }
 137
 138 void
 139 db_trace_self(void)
 140 {
 141         struct unwind_state frame;
 142         uintptr_t sp;
 143
 144         __asm __volatile("mv %0, sp" : "=&r" (sp));
 145
 146         frame.sp = sp;
 147         frame.fp = (uintptr_t)__builtin_frame_address(0);
 148         frame.pc = (uintptr_t)db_trace_self;
 149         db_stack_trace_cmd(curthread, &frame);
 150 }