osfmk/kern/debug.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * @OSF_COPYRIGHT@
  27  */
  28 /*
  29  * Mach Operating System
  30  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  31  * All Rights Reserved.
  32  *
  33  * Permission to use, copy, modify and distribute this software and its
  34  * documentation is hereby granted, provided that both the copyright
  35  * notice and this permission notice appear in all copies of the
  36  * software, derivative works or modified versions, and any portions
  37  * thereof, and that both notices appear in supporting documentation.
  38  *
  39  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  40  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  41  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  42  *
  43  * Carnegie Mellon requests users of this software to return to
  44  *
  45  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  46  *  School of Computer Science
  47  *  Carnegie Mellon University
  48  *  Pittsburgh PA 15213-3890
  49  *
  50  * any improvements or extensions that they make and grant Carnegie Mellon
  51  * the rights to redistribute these changes.
  52  */
  53
  54 #include <mach_assert.h>
  55 #include <mach_kdb.h>
  56 #include <mach_kgdb.h>
  57 #include <mach_kdp.h>
  58 #include <cpus.h>
  59
  60 #include <kern/cpu_number.h>
  61 #include <kern/lock.h>
  62 #include <kern/spl.h>
  63 #include <kern/thread.h>
  64 #include <kern/assert.h>
  65 #include <kern/sched_prim.h>
  66 #include <kern/misc_protos.h>
  67 #include <vm/vm_kern.h>
  68 #include <stdarg.h>
  69
  70 #ifdef  __ppc__
  71 #include <ppc/Firmware.h>
  72 #include <ppc/low_trace.h>
  73 #endif
  74
  75 unsigned int    halt_in_debugger = 0;
  76 unsigned int    switch_debugger = 0;
  77 unsigned int    current_debugger = 0;
  78 unsigned int    active_debugger = 0;
  79 unsigned int    debug_mode=0;
  80 unsigned int    disableDebugOuput = TRUE;
  81 unsigned int    systemLogDiags = FALSE;
  82 unsigned int    logPanicDataToScreen = FALSE;
  83 #ifdef __ppc__
  84         unsigned int    panicDebugging = FALSE;
  85 #else
  86         unsigned int    panicDebugging = TRUE;
  87 #endif
  88
  89 int mach_assert = 1;
  90
  91 const char              *panicstr = (char *) 0;
  92 decl_simple_lock_data(,panic_lock)
  93 int                     paniccpu;
  94 volatile int            panicwait;
  95 volatile int            nestedpanic= 0;
  96 unsigned int            panic_is_inited = 0;
  97 unsigned int            return_on_panic = 0;
  98 wait_queue_t            save_waits[NCPUS];
  99
 100 char *debug_buf;
 101 char *debug_buf_ptr;
 102 unsigned int debug_buf_size = 0;
 103
 104 void
 105 Assert(
 106         const char      *file,
 107         int             line,
 108         const char      *expression)
 109 {
 110         if (!mach_assert) {
 111                 return;
 112         }
 113         panic("{%d} Assertion failed: file \"%s\", line %d: %s\n",
 114                cpu_number(), file, line, expression);
 115 }
 116
 117 /*
 118  *      Carefully use the panic_lock.  There's always a chance that
 119  *      somehow we'll call panic before getting to initialize the
 120  *      panic_lock -- in this case, we'll assume that the world is
 121  *      in uniprocessor mode and just avoid using the panic lock.
 122  */
 123 #define PANIC_LOCK()                                                    \
 124 MACRO_BEGIN                                                             \
 125         if (panic_is_inited)                                            \
 126                 simple_lock(&panic_lock);                               \
 127 MACRO_END
 128
 129 #define PANIC_UNLOCK()                                                  \
 130 MACRO_BEGIN                                                             \
 131         if (panic_is_inited)                                            \
 132                 simple_unlock(&panic_lock);                             \
 133 MACRO_END
 134
 135
 136 void
 137 panic_init(void)
 138 {
 139         simple_lock_init(&panic_lock, ETAP_NO_TRACE);
 140         panic_is_inited = 1;
 141 }
 142
 143 void
 144 panic(const char *str, ...)
 145 {
 146         va_list listp;
 147         spl_t   s;
 148         thread_t thread;
 149
 150         s = splhigh();
 151         disable_preemption();
 152
 153 #ifdef  __ppc__
 154         lastTrace = LLTraceSet(0);              /* Disable low-level tracing */
 155 #endif
 156
 157         thread = current_thread();              /* Get failing thread */
 158         save_waits[cpu_number()] = thread->wait_queue;  /* Save the old value */
 159         thread->wait_queue = 0;                 /* Clear the wait so we do not get double panics when we try locks */
 160
 161         if( logPanicDataToScreen )
 162                 disableDebugOuput = FALSE;
 163
 164         debug_mode = TRUE;
 165 restart:
 166         PANIC_LOCK();
 167         if (panicstr) {
 168                 if (cpu_number() != paniccpu) {
 169                         PANIC_UNLOCK();
 170                         /*
 171                          * Wait until message has been printed to identify correct
 172                          * cpu that made the first panic.
 173                          */
 174                         while (panicwait)
 175                                 continue;
 176                         goto restart;
 177             } else {
 178                         nestedpanic +=1;
 179                         PANIC_UNLOCK();
 180                         Debugger("double panic");
 181                         printf("double panic:  We are hanging here...\n");
 182                         while(1);
 183                         /* NOTREACHED */
 184                 }
 185         }
 186         panicstr = str;
 187         paniccpu = cpu_number();
 188         panicwait = 1;
 189
 190         PANIC_UNLOCK();
 191         kdb_printf("panic(cpu %d): ", (unsigned) paniccpu);
 192         va_start(listp, str);
 193         _doprnt(str, &listp, consdebug_putc, 0);
 194         va_end(listp);
 195         kdb_printf("\n");
 196
 197         /*
 198          * Release panicwait indicator so that other cpus may call Debugger().
 199          */
 200         panicwait = 0;
 201         Debugger("panic");
 202         /*
 203          * Release panicstr so that we can handle normally other panics.
 204          */
 205         PANIC_LOCK();
 206         panicstr = (char *)0;
 207         PANIC_UNLOCK();
 208         thread->wait_queue = save_waits[cpu_number()];  /* Restore the wait queue */
 209         if (return_on_panic) {
 210                 enable_preemption();
 211                 splx(s);
 212                 return;
 213         }
 214         kdb_printf("panic: We are hanging here...\n");
 215         while(1);
 216         /* NOTREACHED */
 217 }
 218
 219 void
 220 log(int level, char *fmt, ...)
 221 {
 222         va_list listp;
 223
 224 #ifdef lint
 225         level++;
 226 #endif /* lint */
 227 #ifdef  MACH_BSD
 228         disable_preemption();
 229         va_start(listp, fmt);
 230         _doprnt(fmt, &listp, conslog_putc, 0);
 231         va_end(listp);
 232         enable_preemption();
 233 #endif
 234 }
 235
 236 void
 237 debug_log_init(void)
 238 {
 239         if (debug_buf_size != 0)
 240                 return;
 241         if (kmem_alloc(kernel_map, (vm_offset_t *) &debug_buf, PAGE_SIZE) != KERN_SUCCESS)
 242                 panic("cannot allocate debug_buf \n");
 243         debug_buf_ptr = debug_buf;
 244         debug_buf_size = PAGE_SIZE;
 245 }
 246
 247 void
 248 debug_putc(char c)
 249 {
 250         if ((debug_buf_size != 0) && ((debug_buf_ptr-debug_buf) < debug_buf_size)) {
 251                 *debug_buf_ptr=c;
 252                 debug_buf_ptr++;
 253         }
 254 }