osfmk/kern/machine.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) 1991,1990,1989,1988,1987 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  */
  52 /*
  53  *      File:   kern/machine.c
  54  *      Author: Avadis Tevanian, Jr.
  55  *      Date:   1987
  56  *
  57  *      Support for machine independent machine abstraction.
  58  */
  59
  60 #include <cpus.h>
  61
  62 #include <string.h>
  63 #include <mach/boolean.h>
  64 #include <mach/kern_return.h>
  65 #include <mach/mach_types.h>
  66 #include <mach/machine.h>
  67 #include <mach/host_info.h>
  68 #include <mach/host_reboot.h>
  69 #include <kern/counters.h>
  70 #include <kern/cpu_data.h>
  71 #include <kern/ipc_host.h>
  72 #include <kern/host.h>
  73 #include <kern/lock.h>
  74 #include <kern/machine.h>
  75 #include <kern/processor.h>
  76 #include <kern/queue.h>
  77 #include <kern/sched.h>
  78 #include <kern/task.h>
  79 #include <kern/thread.h>
  80 #include <kern/thread_swap.h>
  81 #include <kern/misc_protos.h>
  82
  83 #include <kern/mk_sp.h>
  84
  85 /*
  86  *      Exported variables:
  87  */
  88
  89 struct machine_info     machine_info;
  90 struct machine_slot     machine_slot[NCPUS];
  91
  92 static queue_head_t                     processor_action_queue;
  93 static boolean_t                        processor_action_active;
  94 static thread_call_t            processor_action_call;
  95 static thread_call_data_t       processor_action_call_data;
  96 decl_simple_lock_data(static,processor_action_lock)
  97
  98 thread_t                machine_wake_thread;
  99
 100 /* Forwards */
 101 processor_set_t processor_request_action(
 102                                         processor_t                     processor,
 103                                         processor_set_t         new_pset);
 104
 105 void                    processor_doaction(
 106                                         processor_t                     processor);
 107
 108 void                    processor_doshutdown(
 109                                         processor_t                     processor);
 110
 111 /*
 112  *      cpu_up:
 113  *
 114  * Flag specified cpu as up and running.  Called when a processor comes
 115  * online.
 116  */
 117 void
 118 cpu_up(
 119         int             cpu)
 120 {
 121         processor_t                             processor = cpu_to_processor(cpu);
 122         struct machine_slot             *ms;
 123         spl_t                                   s;
 124
 125         /*
 126          * Just twiddle our thumbs; we've got nothing better to do
 127          * yet, anyway.
 128          */
 129         while (!simple_lock_try(&default_pset.processors_lock))
 130                 continue;
 131
 132         s = splsched();
 133         processor_lock(processor);
 134         init_ast_check(processor);
 135         ms = &machine_slot[cpu];
 136         ms->running = TRUE;
 137         machine_info.avail_cpus++;
 138         pset_add_processor(&default_pset, processor);
 139         processor->state = PROCESSOR_RUNNING;
 140         processor_unlock(processor);
 141         splx(s);
 142
 143         simple_unlock(&default_pset.processors_lock);
 144 }
 145
 146 /*
 147  *      cpu_down:
 148  *
 149  *      Flag specified cpu as down.  Called when a processor is about to
 150  *      go offline.
 151  */
 152 void
 153 cpu_down(
 154         int             cpu)
 155 {
 156         processor_t                             processor;
 157         struct machine_slot             *ms;
 158         spl_t                                   s;
 159
 160         processor = cpu_to_processor(cpu);
 161
 162         s = splsched();
 163         processor_lock(processor);
 164         ms = &machine_slot[cpu];
 165         ms->running = FALSE;
 166         machine_info.avail_cpus--;
 167         /*
 168          *      processor has already been removed from pset.
 169          */
 170         processor->processor_set_next = PROCESSOR_SET_NULL;
 171         processor->state = PROCESSOR_OFF_LINE;
 172         processor_unlock(processor);
 173         splx(s);
 174 }
 175
 176 kern_return_t
 177 host_reboot(
 178         host_priv_t                     host_priv,
 179         int                             options)
 180 {
 181         if (host_priv == HOST_PRIV_NULL)
 182                 return (KERN_INVALID_HOST);
 183
 184         assert(host_priv == &realhost);
 185
 186         if (options & HOST_REBOOT_DEBUGGER) {
 187                 Debugger("Debugger");
 188         }
 189         else
 190                 halt_all_cpus(!(options & HOST_REBOOT_HALT));
 191
 192         return (KERN_SUCCESS);
 193 }
 194
 195 /*
 196  * processor_request_action:
 197  *
 198  * Common internals of processor_assign and processor_shutdown.
 199  * If new_pset is null, this is a shutdown, else it's an assign
 200  * and caller must donate a reference.
 201  * For assign operations, it returns an old pset that must be deallocated
 202  * if it's not NULL.
 203  * For shutdown operations, it always returns PROCESSOR_SET_NULL.
 204  */
 205 processor_set_t
 206 processor_request_action(
 207         processor_t                     processor,
 208         processor_set_t         new_pset)
 209 {
 210         processor_set_t pset, old_next_pset;
 211
 212         /*
 213          * Processor must be in a processor set.  Must lock its idle lock to
 214          * get at processor state.
 215          */
 216         pset = processor->processor_set;
 217         simple_lock(&pset->idle_lock);
 218
 219         /*
 220          * If the processor is dispatching, let it finish - it will set its
 221          * state to running very soon.
 222          */
 223         while (*(volatile int *)&processor->state == PROCESSOR_DISPATCHING) {
 224                 simple_unlock(&pset->idle_lock);
 225                 simple_lock(&pset->idle_lock);
 226         }
 227
 228         /*
 229          * Now lock the action queue and do the dirty work.
 230          */
 231         simple_lock(&processor_action_lock);
 232
 233         switch (processor->state) {
 234
 235         case PROCESSOR_IDLE:
 236                 /*
 237                  * Remove from idle queue.
 238                  */
 239                 queue_remove(&pset->idle_queue, processor,
 240                                                 processor_t, processor_queue);
 241                 pset->idle_count--;
 242
 243                 /* fall through ... */
 244         case PROCESSOR_RUNNING:
 245                 /*
 246                  * Put it on the action queue.
 247                  */
 248                 queue_enter(&processor_action_queue, processor,
 249                                                 processor_t,processor_queue);
 250
 251                 /* Fall through ... */
 252         case PROCESSOR_ASSIGN:
 253                 /*
 254                  * And ask the action_thread to do the work.
 255                  */
 256
 257                 if (new_pset == PROCESSOR_SET_NULL) {
 258                         processor->state = PROCESSOR_SHUTDOWN;
 259                         old_next_pset = PROCESSOR_SET_NULL;
 260                 } else {
 261                         processor->state = PROCESSOR_ASSIGN;
 262                         old_next_pset = processor->processor_set_next;
 263                         processor->processor_set_next = new_pset;
 264                 }
 265                 break;
 266
 267         default:
 268                 printf("state: %d\n", processor->state);
 269                 panic("processor_request_action: bad state");
 270         }
 271
 272         if (processor_action_active == FALSE) {
 273                 processor_action_active = TRUE;
 274                 simple_unlock(&processor_action_lock);
 275                 simple_unlock(&pset->idle_lock);
 276                 processor_unlock(processor);
 277                 thread_call_enter(processor_action_call);
 278                 processor_lock(processor);
 279         } else {
 280                 simple_unlock(&processor_action_lock);
 281         simple_unlock(&pset->idle_lock);
 282         }
 283
 284         return (old_next_pset);
 285 }
 286
 287 kern_return_t
 288 processor_assign(
 289         processor_t                     processor,
 290         processor_set_t         new_pset,
 291         boolean_t                       wait)
 292 {
 293 #ifdef  lint
 294         processor++; new_pset++; wait++;
 295 #endif  /* lint */
 296         return (KERN_FAILURE);
 297 }
 298
 299 /*
 300  *      processor_shutdown() queues a processor up for shutdown.
 301  *      Any assignment in progress is overriden.
 302  */
 303 kern_return_t
 304 processor_shutdown(
 305         processor_t             processor)
 306 {
 307         spl_t s;
 308
 309         s = splsched();
 310         processor_lock(processor);
 311         if ((processor->state == PROCESSOR_OFF_LINE) ||
 312                 (processor->state == PROCESSOR_SHUTDOWN)) {
 313                 /*
 314                  * Already shutdown or being shutdown -- nothing to do.
 315                  */
 316                 processor_unlock(processor);
 317                 splx(s);
 318
 319                 return (KERN_SUCCESS);
 320         }
 321
 322         (void) processor_request_action(processor, PROCESSOR_SET_NULL);
 323
 324         assert_wait((event_t)processor, THREAD_UNINT);
 325
 326     processor_unlock(processor);
 327         splx(s);
 328
 329         thread_block((void (*)(void)) 0);
 330
 331         return (KERN_SUCCESS);
 332 }
 333
 334 /*
 335  *      processor_action() shuts down processors or changes their assignment.
 336  */
 337 static void
 338 _processor_action(
 339         thread_call_param_t             p0,
 340         thread_call_param_t             p1)
 341 {
 342         register processor_t    processor;
 343         spl_t s;
 344
 345         s = splsched();
 346         simple_lock(&processor_action_lock);
 347
 348         while (!queue_empty(&processor_action_queue)) {
 349                 processor = (processor_t) queue_first(&processor_action_queue);
 350                 queue_remove(&processor_action_queue, processor,
 351                                                 processor_t, processor_queue);
 352                 simple_unlock(&processor_action_lock);
 353                 splx(s);
 354
 355                 processor_doaction(processor);
 356
 357                 s = splsched();
 358                 simple_lock(&processor_action_lock);
 359         }
 360
 361         processor_action_active = FALSE;
 362         simple_unlock(&processor_action_lock);
 363         splx(s);
 364 }
 365
 366 void
 367 processor_action(void)
 368 {
 369         queue_init(&processor_action_queue);
 370         simple_lock_init(&processor_action_lock, ETAP_THREAD_ACTION);
 371         processor_action_active = FALSE;
 372
 373         thread_call_setup(&processor_action_call_data, _processor_action, NULL);
 374         processor_action_call = &processor_action_call_data;
 375 }
 376
 377 /*
 378  *      processor_doaction actually does the shutdown.  The trick here
 379  *      is to schedule ourselves onto a cpu and then save our
 380  *      context back into the runqs before taking out the cpu.
 381  */
 382 void
 383 processor_doaction(
 384         processor_t                                     processor)
 385 {
 386         thread_t                        self = current_thread();
 387         processor_set_t         pset;
 388         thread_t                        old_thread;
 389         spl_t                           s;
 390
 391         /*
 392          *      Get onto the processor to shutdown
 393          */
 394         thread_bind(self, processor);
 395         thread_block((void (*)(void)) 0);
 396
 397         pset = processor->processor_set;
 398         simple_lock(&pset->processors_lock);
 399
 400         if (pset->processor_count == 1) {
 401                 thread_t                thread;
 402                 extern void             start_cpu_thread(void);
 403
 404                 simple_unlock(&pset->processors_lock);
 405
 406                 /*
 407                  * Create the thread, and point it at the routine.
 408                  */
 409                 thread = kernel_thread_with_priority(
 410                                                                         kernel_task, MAXPRI_KERNEL,
 411                                                                                 start_cpu_thread, TRUE, FALSE);
 412
 413                 disable_preemption();
 414
 415                 s = splsched();
 416                 thread_lock(thread);
 417                 thread->state |= TH_RUN;
 418                 _mk_sp_thread_unblock(thread);
 419                 (void)rem_runq(thread);
 420                 machine_wake_thread = thread;
 421                 thread_unlock(thread);
 422                 splx(s);
 423
 424                 simple_lock(&pset->processors_lock);
 425                 enable_preemption();
 426         }
 427
 428         s = splsched();
 429         processor_lock(processor);
 430
 431         /*
 432          *      Do shutdown, make sure we live when processor dies.
 433          */
 434         if (processor->state != PROCESSOR_SHUTDOWN) {
 435                 panic("action_thread -- bad processor state");
 436         }
 437
 438         pset_remove_processor(pset, processor);
 439         processor_unlock(processor);
 440         simple_unlock(&pset->processors_lock);
 441
 442         /*
 443          *      Clean up.
 444          */
 445         thread_bind(self, PROCESSOR_NULL);
 446         self->continuation = 0;
 447         old_thread = switch_to_shutdown_context(self,
 448                                                                         processor_doshutdown, processor);
 449         thread_dispatch(old_thread);
 450         thread_wakeup((event_t)processor);
 451         splx(s);
 452 }
 453
 454 /*
 455  *      Actually do the processor shutdown.  This is called at splsched,
 456  *      running on the processor's shutdown stack.
 457  */
 458
 459 void
 460 processor_doshutdown(
 461         processor_t             processor)
 462 {
 463         register int    cpu = processor->slot_num;
 464
 465         timer_call_cancel(&processor->quantum_timer);
 466         thread_dispatch(current_thread());
 467         timer_switch(&kernel_timer[cpu]);
 468
 469         /*
 470          *      OK, now exit this cpu.
 471          */
 472         PMAP_DEACTIVATE_KERNEL(cpu);
 473         cpu_data[cpu].active_thread = THREAD_NULL;
 474         active_kloaded[cpu] = THR_ACT_NULL;
 475         cpu_down(cpu);
 476         cpu_sleep();
 477         panic("zombie processor");
 478         /*NOTREACHED*/
 479 }
 480
 481 kern_return_t
 482 host_get_boot_info(
 483         host_priv_t         host_priv,
 484         kernel_boot_info_t  boot_info)
 485 {
 486         char *src = "";
 487         extern char *machine_boot_info(
 488                                 kernel_boot_info_t      boot_info,
 489                                 vm_size_t                       buf_len);
 490
 491         if (host_priv == HOST_PRIV_NULL)
 492                 return (KERN_INVALID_HOST);
 493
 494         assert(host_priv == &realhost);
 495
 496         /*
 497          * Copy first operator string terminated by '\0' followed by
 498          *      standardized strings generated from boot string.
 499          */
 500         src = machine_boot_info(boot_info, KERNEL_BOOT_INFO_MAX);
 501         if (src != boot_info)
 502                 (void) strncpy(boot_info, src, KERNEL_BOOT_INFO_MAX);
 503
 504         return (KERN_SUCCESS);
 505 }