osfmk/kern/debug.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25 /*
  26  * Mach Operating System
  27  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  28  * All Rights Reserved.
  29  *
  30  * Permission to use, copy, modify and distribute this software and its
  31  * documentation is hereby granted, provided that both the copyright
  32  * notice and this permission notice appear in all copies of the
  33  * software, derivative works or modified versions, and any portions
  34  * thereof, and that both notices appear in supporting documentation.
  35  *
  36  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  37  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  38  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  39  *
  40  * Carnegie Mellon requests users of this software to return to
  41  *
  42  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  43  *  School of Computer Science
  44  *  Carnegie Mellon University
  45  *  Pittsburgh PA 15213-3890
  46  *
  47  * any improvements or extensions that they make and grant Carnegie Mellon
  48  * the rights to redistribute these changes.
  49  */
  50
  51 #include <mach_assert.h>
  52 #include <mach_kdb.h>
  53 #include <mach_kgdb.h>
  54 #include <mach_kdp.h>
  55 #include <cpus.h>
  56
  57 #include <kern/cpu_number.h>
  58 #include <kern/lock.h>
  59 #include <kern/spl.h>
  60 #include <kern/thread.h>
  61 #include <kern/assert.h>
  62 #include <kern/sched_prim.h>
  63 #include <kern/misc_protos.h>
  64 #include <vm/vm_kern.h>
  65 #include <stdarg.h>
  66
  67 #ifdef  __ppc__
  68 #include <ppc/Firmware.h>
  69 #include <ppc/low_trace.h>
  70 #endif
  71
  72 unsigned int    halt_in_debugger = 0;
  73 unsigned int    switch_debugger = 0;
  74 unsigned int    current_debugger = 0;
  75 unsigned int    active_debugger = 0;
  76 unsigned int    debug_mode=0;
  77 unsigned int    disableDebugOuput = TRUE;
  78 unsigned int    systemLogDiags = FALSE;
  79 unsigned int    logPanicDataToScreen = FALSE;
  80 #ifdef __ppc__
  81         unsigned int    panicDebugging = FALSE;
  82 #else
  83         unsigned int    panicDebugging = TRUE;
  84 #endif
  85
  86 int mach_assert = 1;
  87
  88 const char              *panicstr = (char *) 0;
  89 decl_simple_lock_data(,panic_lock)
  90 int                     paniccpu;
  91 volatile int            panicwait;
  92 volatile int            nestedpanic= 0;
  93 unsigned int            panic_is_inited = 0;
  94 unsigned int            return_on_panic = 0;
  95 wait_queue_t            save_waits[NCPUS];
  96
  97 char *debug_buf;
  98 char *debug_buf_ptr;
  99 unsigned int debug_buf_size = 0;
 100
 101 void
 102 Assert(
 103         const char      *file,
 104         int             line,
 105         const char      *expression)
 106 {
 107         if (!mach_assert) {
 108                 return;
 109         }
 110         panic("{%d} Assertion failed: file \"%s\", line %d: %s\n",
 111                cpu_number(), file, line, expression);
 112 }
 113
 114 /*
 115  *      Carefully use the panic_lock.  There's always a chance that
 116  *      somehow we'll call panic before getting to initialize the
 117  *      panic_lock -- in this case, we'll assume that the world is
 118  *      in uniprocessor mode and just avoid using the panic lock.
 119  */
 120 #define PANIC_LOCK()                                                    \
 121 MACRO_BEGIN                                                             \
 122         if (panic_is_inited)                                            \
 123                 simple_lock(&panic_lock);                               \
 124 MACRO_END
 125
 126 #define PANIC_UNLOCK()                                                  \
 127 MACRO_BEGIN                                                             \
 128         if (panic_is_inited)                                            \
 129                 simple_unlock(&panic_lock);                             \
 130 MACRO_END
 131
 132
 133 void
 134 panic_init(void)
 135 {
 136         simple_lock_init(&panic_lock, ETAP_NO_TRACE);
 137         panic_is_inited = 1;
 138 }
 139
 140 void
 141 panic(const char *str, ...)
 142 {
 143         va_list listp;
 144         spl_t   s;
 145         thread_t thread;
 146
 147         s = splhigh();
 148         disable_preemption();
 149
 150 #ifdef  __ppc__
 151         lastTrace = LLTraceSet(0);              /* Disable low-level tracing */
 152 #endif
 153
 154         thread = current_thread();              /* Get failing thread */
 155         save_waits[cpu_number()] = thread->wait_queue;  /* Save the old value */
 156         thread->wait_queue = 0;                 /* Clear the wait so we do not get double panics when we try locks */
 157
 158         if( logPanicDataToScreen )
 159                 disableDebugOuput = FALSE;
 160
 161         debug_mode = TRUE;
 162 restart:
 163         PANIC_LOCK();
 164         if (panicstr) {
 165                 if (cpu_number() != paniccpu) {
 166                         PANIC_UNLOCK();
 167                         /*
 168                          * Wait until message has been printed to identify correct
 169                          * cpu that made the first panic.
 170                          */
 171                         while (panicwait)
 172                                 continue;
 173                         goto restart;
 174             } else {
 175                         nestedpanic +=1;
 176                         PANIC_UNLOCK();
 177                         Debugger("double panic");
 178                         printf("double panic:  We are hanging here...\n");
 179                         while(1);
 180                         /* NOTREACHED */
 181                 }
 182         }
 183         panicstr = str;
 184         paniccpu = cpu_number();
 185         panicwait = 1;
 186
 187         PANIC_UNLOCK();
 188         kdb_printf("panic(cpu %d): ", (unsigned) paniccpu);
 189         va_start(listp, str);
 190         _doprnt(str, &listp, consdebug_putc, 0);
 191         va_end(listp);
 192         kdb_printf("\n");
 193
 194         /*
 195          * Release panicwait indicator so that other cpus may call Debugger().
 196          */
 197         panicwait = 0;
 198         Debugger("panic");
 199         /*
 200          * Release panicstr so that we can handle normally other panics.
 201          */
 202         PANIC_LOCK();
 203         panicstr = (char *)0;
 204         PANIC_UNLOCK();
 205         thread->wait_queue = save_waits[cpu_number()];  /* Restore the wait queue */
 206         if (return_on_panic) {
 207                 enable_preemption();
 208                 splx(s);
 209                 return;
 210         }
 211         kdb_printf("panic: We are hanging here...\n");
 212         while(1);
 213         /* NOTREACHED */
 214 }
 215
 216 void
 217 log(int level, char *fmt, ...)
 218 {
 219         va_list listp;
 220
 221 #ifdef lint
 222         level++;
 223 #endif /* lint */
 224 #ifdef  MACH_BSD
 225         disable_preemption();
 226         va_start(listp, fmt);
 227         _doprnt(fmt, &listp, conslog_putc, 0);
 228         va_end(listp);
 229         enable_preemption();
 230 #endif
 231 }
 232
 233 void
 234 debug_log_init(void)
 235 {
 236         if (debug_buf_size != 0)
 237                 return;
 238         if (kmem_alloc(kernel_map, (vm_offset_t *) &debug_buf, PAGE_SIZE) != KERN_SUCCESS)
 239                 panic("cannot allocate debug_buf \n");
 240         debug_buf_ptr = debug_buf;
 241         debug_buf_size = PAGE_SIZE;
 242 }
 243
 244 void
 245 debug_putc(char c)
 246 {
 247         if ((debug_buf_size != 0) && ((debug_buf_ptr-debug_buf) < debug_buf_size)) {
 248                 *debug_buf_ptr=c;
 249                 debug_buf_ptr++;
 250         }
 251 }