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()
  57 {
  58
  59 }
  60
  61 int
  62 db_md_clr_watchpoint(db_expr_t addr, db_expr_t size)
  63 {
  64
  65         return (0);
  66 }
  67
  68 int
  69 db_md_set_watchpoint(db_expr_t addr, db_expr_t size)
  70 {
  71
  72         return (0);
  73 }
  74
  75 static void
  76 db_stack_trace_cmd(struct thread *td, struct unwind_state *frame)
  77 {
  78         const char *name;
  79         db_expr_t offset;
  80         db_expr_t value;
  81         c_db_sym_t sym;
  82         uint64_t pc;
  83
  84         while (1) {
  85                 pc = frame->pc;
  86
  87                 sym = db_search_symbol(pc, DB_STGY_ANY, &offset);
  88                 if (sym == C_DB_SYM_NULL) {
  89                         value = 0;
  90                         name = "(null)";
  91                 } else
  92                         db_symbol_values(sym, &name, &value);
  93
  94                 db_printf("%s() at ", name);
  95                 db_printsym(frame->pc, DB_STGY_PROC);
  96                 db_printf("\n");
  97
  98                 if (strcmp(name, "cpu_exception_handler_supervisor") == 0 ||
  99                     strcmp(name, "cpu_exception_handler_user") == 0) {
 100                         struct trapframe *tf;
 101
 102                         tf = (struct trapframe *)(uintptr_t)frame->sp;
 103                         if (!kstack_contains(td, (vm_offset_t)tf,
 104                             sizeof(*tf))) {
 105                                 db_printf("--- invalid trapframe %p\n", tf);
 106                                 break;
 107                         }
 108
 109                         if ((tf->tf_scause & SCAUSE_INTR) != 0)
 110                                 db_printf("--- interrupt %ld\n",
 111                                     tf->tf_scause & SCAUSE_CODE);
 112                         else
 113                                 db_printf("--- exception %ld, tval = %#lx\n",
 114                                     tf->tf_scause & SCAUSE_CODE,
 115                                     tf->tf_stval);
 116                         frame->sp = tf->tf_sp;
 117                         frame->fp = tf->tf_s[0];
 118                         frame->pc = tf->tf_sepc;
 119                         if (!INKERNEL(frame->fp))
 120                                 break;
 121                         continue;
 122                 }
 123
 124                 if (strcmp(name, "fork_trampoline") == 0)
 125                         break;
 126
 127                 if (!unwind_frame(td, frame))
 128                         break;
 129         }
 130 }
 131
 132 int
 133 db_trace_thread(struct thread *thr, int count)
 134 {
 135         struct unwind_state frame;
 136         struct pcb *ctx;
 137
 138         ctx = kdb_thr_ctx(thr);
 139
 140         frame.sp = ctx->pcb_sp;
 141         frame.fp = ctx->pcb_s[0];
 142         frame.pc = ctx->pcb_ra;
 143         db_stack_trace_cmd(thr, &frame);
 144         return (0);
 145 }
 146
 147 void
 148 db_trace_self(void)
 149 {
 150         struct unwind_state frame;
 151         uintptr_t sp;
 152
 153         __asm __volatile("mv %0, sp" : "=&r" (sp));
 154
 155         frame.sp = sp;
 156         frame.fp = (uintptr_t)__builtin_frame_address(0);
 157         frame.pc = (uintptr_t)db_trace_self;
 158         db_stack_trace_cmd(curthread, &frame);
 159 }