osfmk/ddb/db_task_thread.c

   1 /*
   2  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 /*
  57  */
  58
  59 #include <kern/kern_types.h>
  60 #include <kern/processor.h>
  61 #include <machine/db_machdep.h>
  62 #include <ddb/db_task_thread.h>
  63 #include <ddb/db_variables.h>
  64 #include <ddb/db_command.h>
  65 #include <ddb/db_expr.h>
  66 #include <ddb/db_lex.h>
  67 #include <ddb/db_output.h>              /* For db_printf() */
  68 #include <ddb/db_sym.h>
  69
  70 /*
  71  * Following constants are used to prevent infinite loop of task
  72  * or thread search due to the incorrect list.
  73  */
  74 #define DB_MAX_TASKID   0x10000         /* max # of tasks */
  75 #define DB_MAX_THREADID 0x10000         /* max # of threads in a task */
  76 #define DB_MAX_PSETS    0x10000         /* max # of processor sets */
  77
  78 task_t          db_default_task = TASK_NULL;    /* default target task */
  79 thread_t        db_default_act = THREAD_NULL;           /* default target thr_act */
  80
  81
  82
  83 /* Prototypes for functions local to this file.
  84  */
  85 task_t db_lookup_task_id(register int task_id);
  86
  87 static thread_t db_lookup_act_id(
  88         task_t   task,
  89         register int thread_id);
  90
  91
  92
  93 /*
  94  * search valid task queue, and return the queue position as the task id
  95  */
  96 int
  97 db_lookup_task(task_t target_task)
  98 {
  99         register task_t task;
 100         register int task_id;
 101
 102         task_id = 0;
 103         if (queue_first(&tasks) == 0)
 104                 return(-1);
 105         queue_iterate(&tasks, task, task_t, tasks) {
 106                 if (target_task == task)
 107                     return(task_id);
 108                 if (task_id++ >= DB_MAX_TASKID)
 109                     return(-1);
 110         }
 111         return(-1);
 112 }
 113
 114 /*
 115  * search thread queue of the task, and return the queue position
 116  */
 117 int
 118 db_lookup_task_act(
 119         task_t          task,
 120         thread_t        target_act)
 121 {
 122         register thread_t thr_act;
 123         register int act_id;
 124
 125         act_id = 0;
 126         if (queue_first(&task->threads) == 0)
 127             return(-1);
 128         queue_iterate(&task->threads, thr_act, thread_t, task_threads) {
 129             if (target_act == thr_act)
 130                 return(act_id);
 131             if (act_id++ >= DB_MAX_THREADID)
 132                 return(-1);
 133         }
 134         return(-1);
 135 }
 136
 137 /*
 138  * search thr_act queue of every valid task, and return the queue position
 139  * as the thread id.
 140  */
 141 int
 142 db_lookup_act(thread_t target_act)
 143 {
 144         register int act_id;
 145         register task_t task;
 146         register int ntask = 0;
 147
 148         if (queue_first(&tasks) == 0)
 149                 return(-1);
 150         queue_iterate(&tasks, task, task_t, tasks) {
 151                 if (ntask++ > DB_MAX_TASKID)
 152                     return(-1);
 153                 if (task->thread_count == 0)
 154                     continue;
 155                 act_id = db_lookup_task_act(task, target_act);
 156                 if (act_id >= 0)
 157                     return(act_id);
 158         }
 159         return(-1);
 160 }
 161
 162 /*
 163  * check the address is a valid thread address
 164  */
 165 int force_act_lookup = 0;
 166 boolean_t
 167 db_check_act_address_valid(thread_t thr_act)
 168 {
 169         if (!force_act_lookup && db_lookup_act(thr_act) < 0) {
 170             db_printf("Bad thr_act address 0x%x\n", thr_act);
 171             db_flush_lex();
 172             return(FALSE);
 173         } else
 174             return(TRUE);
 175 }
 176
 177 /*
 178  * convert task_id(queue postion) to task address
 179  */
 180 task_t
 181 db_lookup_task_id(int task_id)
 182 {
 183         register task_t task;
 184
 185         if (task_id > DB_MAX_TASKID)
 186             return(TASK_NULL);
 187         if (queue_first(&tasks) == 0)
 188                 return(TASK_NULL);
 189         queue_iterate(&tasks, task, task_t, tasks) {
 190                 if (task_id-- <= 0)
 191                         return(task);
 192         }
 193         return(TASK_NULL);
 194 }
 195
 196 /*
 197  * convert (task_id, act_id) pair to thr_act address
 198  */
 199 static thread_t
 200 db_lookup_act_id(
 201         task_t   task,
 202         register int act_id)
 203 {
 204         register thread_t thr_act;
 205
 206
 207         if (act_id > DB_MAX_THREADID)
 208             return(THREAD_NULL);
 209         if (queue_first(&task->threads) == 0)
 210             return(THREAD_NULL);
 211         queue_iterate(&task->threads, thr_act, thread_t, task_threads) {
 212             if (act_id-- <= 0)
 213                 return(thr_act);
 214         }
 215         return(THREAD_NULL);
 216 }
 217
 218 /*
 219  * get next parameter from a command line, and check it as a valid
 220  * thread address
 221  */
 222 boolean_t
 223 db_get_next_act(
 224         thread_t        *actp,
 225         int             position)
 226 {
 227         db_expr_t       value;
 228         thread_t        thr_act;
 229
 230         *actp = THREAD_NULL;
 231         if (db_expression(&value)) {
 232             thr_act = (thread_t)(unsigned long)value;
 233             if (!db_check_act_address_valid(thr_act)) {
 234                 db_flush_lex();
 235                 return(FALSE);
 236             }
 237         } else if (position <= 0) {
 238             thr_act = db_default_act;
 239         } else
 240             return(FALSE);
 241         *actp = thr_act;
 242         return(TRUE);
 243 }
 244
 245 /*
 246  * check the default thread is still valid
 247  *      ( it is called in entering DDB session )
 248  */
 249 void
 250 db_init_default_act(void)
 251 {
 252         if (db_lookup_act(db_default_act) < 0) {
 253             db_default_act = THREAD_NULL;
 254             db_default_task = TASK_NULL;
 255         } else
 256             db_default_task = db_default_act->task;
 257 }
 258
 259 /*
 260  * set or get default thread which is used when /t or :t option is specified
 261  * in the command line
 262  */
 263 int
 264 db_set_default_act(__unused struct db_variable *vp, db_expr_t *valuep,
 265                    int flag, __unused db_var_aux_param_t ap)
 266 {
 267         thread_t        thr_act;
 268         int             task_id;
 269         int             act_id;
 270
 271         if (flag == DB_VAR_SHOW) {
 272             db_printf("%#n", db_default_act);
 273             task_id = db_lookup_task(db_default_task);
 274             if (task_id != -1) {
 275                 act_id = db_lookup_act(db_default_act);
 276                 if (act_id != -1) {
 277                     db_printf(" (task%d.%d)", task_id, act_id);
 278                 }
 279             }
 280             return(0);
 281         }
 282
 283         if (flag != DB_VAR_SET) {
 284             *valuep = (db_expr_t)(unsigned long)db_default_act;
 285             return(0);
 286         }
 287         thr_act = (thread_t)(unsigned long)*valuep;
 288         if (thr_act != THREAD_NULL && !db_check_act_address_valid(thr_act))
 289             db_error(0);
 290             /* NOTREACHED */
 291         db_default_act = thr_act;
 292         if (thr_act)
 293                 db_default_task = thr_act->task;
 294         return(0);
 295 }
 296
 297 /*
 298  * convert $taskXXX[.YYY] type DDB variable to task or thread address
 299  */
 300 int
 301 db_get_task_act(__unused struct db_variable *vp, db_expr_t *valuep, int flag,
 302                 db_var_aux_param_t ap)
 303 {
 304         task_t                  task;
 305         thread_t                thr_act;
 306         int                     task_id;
 307
 308         if (flag == DB_VAR_SHOW) {
 309             db_printf("%#n", db_default_task);
 310             task_id = db_lookup_task(db_default_task);
 311             if (task_id != -1)
 312                 db_printf(" (task%d)", task_id);
 313             return(0);
 314         }
 315
 316         if (flag != DB_VAR_GET) {
 317             db_error("Cannot set to $task variable\n");
 318             /* NOTREACHED */
 319         }
 320         if ((task = db_lookup_task_id(ap->suffix[0])) == TASK_NULL) {
 321             db_printf("no such task($task%d)\n", ap->suffix[0]);
 322             db_error(0);
 323             /* NOTREACHED */
 324         }
 325         if (ap->level <= 1) {
 326             *valuep = (db_expr_t)(unsigned long)task;
 327             return(0);
 328         }
 329         if ((thr_act = db_lookup_act_id(task, ap->suffix[1])) == THREAD_NULL){
 330             db_printf("no such thr_act($task%d.%d)\n",
 331                                         ap->suffix[0], ap->suffix[1]);
 332             db_error(0);
 333             /* NOTREACHED */
 334         }
 335         *valuep = (db_expr_t)(unsigned long)thr_act;
 336         return(0);
 337 }