osfmk/kern/machine.c

   1 /*
   2  * Copyright (c) 2000-2009 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) 1991,1990,1989,1988,1987 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  *      File:   kern/machine.c
  60  *      Author: Avadis Tevanian, Jr.
  61  *      Date:   1987
  62  *
  63  *      Support for machine independent machine abstraction.
  64  */
  65
  66 #include <string.h>
  67
  68 #include <mach/mach_types.h>
  69 #include <mach/boolean.h>
  70 #include <mach/kern_return.h>
  71 #include <mach/machine.h>
  72 #include <mach/host_info.h>
  73 #include <mach/host_reboot.h>
  74 #include <mach/host_priv_server.h>
  75 #include <mach/processor_server.h>
  76
  77 #include <kern/kern_types.h>
  78 #include <kern/counters.h>
  79 #include <kern/cpu_data.h>
  80 #include <kern/ipc_host.h>
  81 #include <kern/host.h>
  82 #include <kern/machine.h>
  83 #include <kern/misc_protos.h>
  84 #include <kern/processor.h>
  85 #include <kern/queue.h>
  86 #include <kern/sched.h>
  87 #include <kern/task.h>
  88 #include <kern/thread.h>
  89
  90 #include <machine/commpage.h>
  91
  92 #if HIBERNATION
  93 #include <IOKit/IOHibernatePrivate.h>
  94 #endif
  95 #include <IOKit/IOPlatformExpert.h>
  96
  97 #if CONFIG_DTRACE
  98 extern void (*dtrace_cpu_state_changed_hook)(int, boolean_t);
  99 #endif
 100
 101 /*
 102  *      Exported variables:
 103  */
 104
 105 struct machine_info     machine_info;
 106
 107 /* Forwards */
 108 void                    processor_doshutdown(
 109                                         processor_t                     processor);
 110
 111 /*
 112  *      processor_up:
 113  *
 114  *      Flag processor as up and running, and available
 115  *      for scheduling.
 116  */
 117 void
 118 processor_up(
 119         processor_t                     processor)
 120 {
 121         processor_set_t         pset;
 122         spl_t                           s;
 123
 124         s = splsched();
 125         init_ast_check(processor);
 126         pset = processor->processor_set;
 127         pset_lock(pset);
 128         ++pset->online_processor_count;
 129         enqueue_tail(&pset->active_queue, (queue_entry_t)processor);
 130         processor->state = PROCESSOR_RUNNING;
 131         (void)hw_atomic_add(&processor_avail_count, 1);
 132         commpage_update_active_cpus();
 133         pset_unlock(pset);
 134         ml_cpu_up();
 135         splx(s);
 136
 137 #if CONFIG_DTRACE
 138         if (dtrace_cpu_state_changed_hook)
 139                 (*dtrace_cpu_state_changed_hook)(processor->cpu_id, TRUE);
 140 #endif
 141 }
 142 #include <atm/atm_internal.h>
 143
 144 kern_return_t
 145 host_reboot(
 146         host_priv_t             host_priv,
 147         int                             options)
 148 {
 149         if (host_priv == HOST_PRIV_NULL)
 150                 return (KERN_INVALID_HOST);
 151
 152         assert(host_priv == &realhost);
 153
 154 #if DEVELOPMENT || DEBUG
 155         if (options & HOST_REBOOT_DEBUGGER) {
 156                 Debugger("Debugger");
 157                 return (KERN_SUCCESS);
 158         }
 159 #endif
 160
 161     if (options & HOST_REBOOT_UPSDELAY) {
 162         // UPS power cutoff path
 163         PEHaltRestart( kPEUPSDelayHaltCPU );
 164     } else {
 165        halt_all_cpus(!(options & HOST_REBOOT_HALT));
 166     }
 167
 168         return (KERN_SUCCESS);
 169 }
 170
 171 kern_return_t
 172 processor_assign(
 173         __unused processor_t            processor,
 174         __unused processor_set_t        new_pset,
 175         __unused boolean_t              wait)
 176 {
 177         return (KERN_FAILURE);
 178 }
 179
 180 kern_return_t
 181 processor_shutdown(
 182         processor_t                     processor)
 183 {
 184         processor_set_t         pset;
 185         spl_t                           s;
 186
 187         s = splsched();
 188         pset = processor->processor_set;
 189         pset_lock(pset);
 190         if (processor->state == PROCESSOR_OFF_LINE) {
 191                 /*
 192                  * Success if already shutdown.
 193                  */
 194                 pset_unlock(pset);
 195                 splx(s);
 196
 197                 return (KERN_SUCCESS);
 198         }
 199
 200         if (processor->state == PROCESSOR_START) {
 201                 /*
 202                  * Failure if currently being started.
 203                  */
 204                 pset_unlock(pset);
 205                 splx(s);
 206
 207                 return (KERN_FAILURE);
 208         }
 209
 210         /*
 211          * If the processor is dispatching, let it finish.
 212          */
 213         while (processor->state == PROCESSOR_DISPATCHING) {
 214                 pset_unlock(pset);
 215                 splx(s);
 216                 delay(1);
 217                 s = splsched();
 218                 pset_lock(pset);
 219         }
 220
 221         /*
 222          * Success if already being shutdown.
 223          */
 224         if (processor->state == PROCESSOR_SHUTDOWN) {
 225                 pset_unlock(pset);
 226                 splx(s);
 227
 228                 return (KERN_SUCCESS);
 229         }
 230
 231         if (processor->state == PROCESSOR_IDLE)
 232                 remqueue((queue_entry_t)processor);
 233         else
 234         if (processor->state == PROCESSOR_RUNNING)
 235                 remqueue((queue_entry_t)processor);
 236
 237         processor->state = PROCESSOR_SHUTDOWN;
 238
 239         pset_unlock(pset);
 240
 241         processor_doshutdown(processor);
 242         splx(s);
 243
 244         cpu_exit_wait(processor->cpu_id);
 245
 246         return (KERN_SUCCESS);
 247 }
 248
 249 /*
 250  * Called with interrupts disabled.
 251  */
 252 void
 253 processor_doshutdown(
 254         processor_t                     processor)
 255 {
 256         thread_t                        old_thread, self = current_thread();
 257         processor_t                     prev;
 258         processor_set_t                 pset;
 259
 260         /*
 261          *      Get onto the processor to shutdown
 262          */
 263         prev = thread_bind(processor);
 264         thread_block(THREAD_CONTINUE_NULL);
 265
 266         assert(processor->state == PROCESSOR_SHUTDOWN);
 267
 268 #if CONFIG_DTRACE
 269         if (dtrace_cpu_state_changed_hook)
 270                 (*dtrace_cpu_state_changed_hook)(processor->cpu_id, FALSE);
 271 #endif
 272
 273         ml_cpu_down();
 274
 275 #if HIBERNATION
 276         if (processor_avail_count < 2) {
 277                 hibernate_vm_lock();
 278                 hibernate_vm_unlock();
 279         }
 280 #endif
 281
 282         pset = processor->processor_set;
 283         pset_lock(pset);
 284         processor->state = PROCESSOR_OFF_LINE;
 285         --pset->online_processor_count;
 286         (void)hw_atomic_sub(&processor_avail_count, 1);
 287         commpage_update_active_cpus();
 288         SCHED(processor_queue_shutdown)(processor);
 289         /* pset lock dropped */
 290
 291         /*
 292          * Continue processor shutdown in shutdown context.
 293          *
 294          * We save the current context in machine_processor_shutdown in such a way
 295          * that when this thread is next invoked it will return from here instead of
 296          * from the machine_switch_context() in thread_invoke like a normal context switch.
 297          *
 298          * As such, 'old_thread' is neither the idle thread nor the current thread - it's whatever
 299          * thread invoked back to this one. (Usually, it's another processor's idle thread.)
 300          *
 301          * TODO: Make this a real thread_run of the idle_thread, so we don't have to keep this in sync
 302          * with thread_invoke.
 303          */
 304         thread_bind(prev);
 305         old_thread = machine_processor_shutdown(self, processor_offline, processor);
 306
 307         thread_dispatch(old_thread, self);
 308 }
 309
 310 /*
 311  * Complete the shutdown and place the processor offline.
 312  *
 313  * Called at splsched in the shutdown context.
 314  * This performs a minimal thread_invoke() to the idle thread,
 315  * so it needs to be kept in sync with what thread_invoke() does.
 316  *
 317  * The onlining half of this is done in load_context().
 318  */
 319 void
 320 processor_offline(
 321         processor_t                     processor)
 322 {
 323         assert(processor == current_processor());
 324         assert(processor->active_thread == current_thread());
 325
 326         thread_t old_thread = processor->active_thread;
 327         thread_t new_thread = processor->idle_thread;
 328
 329         processor->active_thread = new_thread;
 330         processor->current_pri = IDLEPRI;
 331         processor->current_thmode = TH_MODE_NONE;
 332         processor->starting_pri = IDLEPRI;
 333         processor->current_sfi_class = SFI_CLASS_KERNEL;
 334         processor->deadline = UINT64_MAX;
 335         new_thread->last_processor = processor;
 336
 337         uint64_t ctime = mach_absolute_time();
 338
 339         processor->last_dispatch = ctime;
 340         old_thread->last_run_time = ctime;
 341
 342         /* Update processor->thread_timer and ->kernel_timer to point to the new thread */
 343         thread_timer_event(ctime, &new_thread->system_timer);
 344         PROCESSOR_DATA(processor, kernel_timer) = &new_thread->system_timer;
 345
 346         timer_stop(PROCESSOR_DATA(processor, current_state), ctime);
 347
 348         KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
 349                                   MACHDBG_CODE(DBG_MACH_SCHED, MACH_SCHED) | DBG_FUNC_NONE,
 350                                   old_thread->reason, (uintptr_t)thread_tid(new_thread),
 351                                   old_thread->sched_pri, new_thread->sched_pri, 0);
 352
 353         machine_set_current_thread(new_thread);
 354
 355         thread_dispatch(old_thread, new_thread);
 356
 357         PMAP_DEACTIVATE_KERNEL(processor->cpu_id);
 358
 359         cpu_sleep();
 360         panic("zombie processor");
 361         /*NOTREACHED*/
 362 }
 363
 364 kern_return_t
 365 host_get_boot_info(
 366         host_priv_t         host_priv,
 367         kernel_boot_info_t  boot_info)
 368 {
 369         const char *src = "";
 370         if (host_priv == HOST_PRIV_NULL)
 371                 return (KERN_INVALID_HOST);
 372
 373         assert(host_priv == &realhost);
 374
 375         /*
 376          * Copy first operator string terminated by '\0' followed by
 377          *      standardized strings generated from boot string.
 378          */
 379         src = machine_boot_info(boot_info, KERNEL_BOOT_INFO_MAX);
 380         if (src != boot_info)
 381                 (void) strncpy(boot_info, src, KERNEL_BOOT_INFO_MAX);
 382
 383         return (KERN_SUCCESS);
 384 }