arch/parisc/kernel/smp.c

   1 /*
   2 ** SMP Support
   3 **
   4 ** Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
   5 ** Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
   6 ** Copyright (C) 2001,2004 Grant Grundler <grundler@parisc-linux.org>
   7 **
   8 ** Lots of stuff stolen from arch/alpha/kernel/smp.c
   9 ** ...and then parisc stole from arch/ia64/kernel/smp.c. Thanks David! :^)
  10 **
  11 ** Thanks to John Curry and Ullas Ponnadi. I learned alot from their work.
  12 ** -grant (1/12/2001)
  13 **
  14 **      This program is free software; you can redistribute it and/or modify
  15 **      it under the terms of the GNU General Public License as published by
  16 **      the Free Software Foundation; either version 2 of the License, or
  17 **      (at your option) any later version.
  18 */
  19 #undef ENTRY_SYS_CPUS   /* syscall support for iCOD-like functionality */
  20
  21 #include <linux/config.h>
  22
  23 #include <linux/types.h>
  24 #include <linux/spinlock.h>
  25 #include <linux/slab.h>
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/sched.h>
  30 #include <linux/init.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/smp.h>
  33 #include <linux/kernel_stat.h>
  34 #include <linux/mm.h>
  35 #include <linux/delay.h>
  36 #include <linux/bitops.h>
  37
  38 #include <asm/system.h>
  39 #include <asm/atomic.h>
  40 #include <asm/current.h>
  41 #include <asm/delay.h>
  42 #include <asm/pgalloc.h>        /* for flush_tlb_all() proto/macro */
  43
  44 #include <asm/io.h>
  45 #include <asm/irq.h>            /* for CPU_IRQ_REGION and friends */
  46 #include <asm/mmu_context.h>
  47 #include <asm/page.h>
  48 #include <asm/pgtable.h>
  49 #include <asm/pgalloc.h>
  50 #include <asm/processor.h>
  51 #include <asm/ptrace.h>
  52 #include <asm/unistd.h>
  53 #include <asm/cacheflush.h>
  54
  55 #define kDEBUG 0
  56
  57 DEFINE_SPINLOCK(smp_lock);
  58
  59 volatile struct task_struct *smp_init_current_idle_task;
  60
  61 static volatile int cpu_now_booting __read_mostly = 0;  /* track which CPU is booting */
  62
  63 static int parisc_max_cpus __read_mostly = 1;
  64
  65 /* online cpus are ones that we've managed to bring up completely
  66  * possible cpus are all valid cpu
  67  * present cpus are all detected cpu
  68  *
  69  * On startup we bring up the "possible" cpus. Since we discover
  70  * CPUs later, we add them as hotplug, so the possible cpu mask is
  71  * empty in the beginning.
  72  */
  73
  74 cpumask_t cpu_online_map   __read_mostly = CPU_MASK_NONE;       /* Bitmap of online CPUs */
  75 cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL;        /* Bitmap of Present CPUs */
  76
  77 EXPORT_SYMBOL(cpu_online_map);
  78 EXPORT_SYMBOL(cpu_possible_map);
  79
  80
  81 struct smp_call_struct {
  82         void (*func) (void *info);
  83         void *info;
  84         long wait;
  85         atomic_t unstarted_count;
  86         atomic_t unfinished_count;
  87 };
  88 static volatile struct smp_call_struct *smp_call_function_data;
  89
  90 enum ipi_message_type {
  91         IPI_NOP=0,
  92         IPI_RESCHEDULE=1,
  93         IPI_CALL_FUNC,
  94         IPI_CPU_START,
  95         IPI_CPU_STOP,
  96         IPI_CPU_TEST
  97 };
  98
  99
 100 /********** SMP inter processor interrupt and communication routines */
 101
 102 #undef PER_CPU_IRQ_REGION
 103 #ifdef PER_CPU_IRQ_REGION
 104 /* XXX REVISIT Ignore for now.
 105 **    *May* need this "hook" to register IPI handler
 106 **    once we have perCPU ExtIntr switch tables.
 107 */
 108 static void
 109 ipi_init(int cpuid)
 110 {
 111
 112         /* If CPU is present ... */
 113 #ifdef ENTRY_SYS_CPUS
 114         /* *and* running (not stopped) ... */
 115 #error iCOD support wants state checked here.
 116 #endif
 117
 118 #error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region
 119
 120         if(cpu_online(cpuid) )
 121         {
 122                 switch_to_idle_task(current);
 123         }
 124
 125         return;
 126 }
 127 #endif
 128
 129
 130 /*
 131 ** Yoink this CPU from the runnable list...
 132 **
 133 */
 134 static void
 135 halt_processor(void)
 136 {
 137 #ifdef ENTRY_SYS_CPUS
 138 #error halt_processor() needs rework
 139 /*
 140 ** o migrate I/O interrupts off this CPU.
 141 ** o leave IPI enabled - __cli() will disable IPI.
 142 ** o leave CPU in online map - just change the state
 143 */
 144         cpu_data[this_cpu].state = STATE_STOPPED;
 145         mark_bh(IPI_BH);
 146 #else
 147         /* REVISIT : redirect I/O Interrupts to another CPU? */
 148         /* REVISIT : does PM *know* this CPU isn't available? */
 149         cpu_clear(smp_processor_id(), cpu_online_map);
 150         local_irq_disable();
 151         for (;;)
 152                 ;
 153 #endif
 154 }
 155
 156
 157 irqreturn_t
 158 ipi_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 159 {
 160         int this_cpu = smp_processor_id();
 161         struct cpuinfo_parisc *p = &cpu_data[this_cpu];
 162         unsigned long ops;
 163         unsigned long flags;
 164
 165         /* Count this now; we may make a call that never returns. */
 166         p->ipi_count++;
 167
 168         mb();   /* Order interrupt and bit testing. */
 169
 170         for (;;) {
 171                 spin_lock_irqsave(&(p->lock),flags);
 172                 ops = p->pending_ipi;
 173                 p->pending_ipi = 0;
 174                 spin_unlock_irqrestore(&(p->lock),flags);
 175
 176                 mb(); /* Order bit clearing and data access. */
 177
 178                 if (!ops)
 179                     break;
 180
 181                 while (ops) {
 182                         unsigned long which = ffz(~ops);
 183
 184                         ops &= ~(1 << which);
 185
 186                         switch (which) {
 187                         case IPI_NOP:
 188 #if (kDEBUG>=100)
 189                                 printk(KERN_DEBUG "CPU%d IPI_NOP\n",this_cpu);
 190 #endif /* kDEBUG */
 191                                 break;
 192
 193                         case IPI_RESCHEDULE:
 194 #if (kDEBUG>=100)
 195                                 printk(KERN_DEBUG "CPU%d IPI_RESCHEDULE\n",this_cpu);
 196 #endif /* kDEBUG */
 197                                 /*
 198                                  * Reschedule callback.  Everything to be
 199                                  * done is done by the interrupt return path.
 200                                  */
 201                                 break;
 202
 203                         case IPI_CALL_FUNC:
 204 #if (kDEBUG>=100)
 205                                 printk(KERN_DEBUG "CPU%d IPI_CALL_FUNC\n",this_cpu);
 206 #endif /* kDEBUG */
 207                                 {
 208                                         volatile struct smp_call_struct *data;
 209                                         void (*func)(void *info);
 210                                         void *info;
 211                                         int wait;
 212
 213                                         data = smp_call_function_data;
 214                                         func = data->func;
 215                                         info = data->info;
 216                                         wait = data->wait;
 217
 218                                         mb();
 219                                         atomic_dec ((atomic_t *)&data->unstarted_count);
 220
 221                                         /* At this point, *data can't
 222                                          * be relied upon.
 223                                          */
 224
 225                                         (*func)(info);
 226
 227                                         /* Notify the sending CPU that the
 228                                          * task is done.
 229                                          */
 230                                         mb();
 231                                         if (wait)
 232                                                 atomic_dec ((atomic_t *)&data->unfinished_count);
 233                                 }
 234                                 break;
 235
 236                         case IPI_CPU_START:
 237 #if (kDEBUG>=100)
 238                                 printk(KERN_DEBUG "CPU%d IPI_CPU_START\n",this_cpu);
 239 #endif /* kDEBUG */
 240 #ifdef ENTRY_SYS_CPUS
 241                                 p->state = STATE_RUNNING;
 242 #endif
 243                                 break;
 244
 245                         case IPI_CPU_STOP:
 246 #if (kDEBUG>=100)
 247                                 printk(KERN_DEBUG "CPU%d IPI_CPU_STOP\n",this_cpu);
 248 #endif /* kDEBUG */
 249 #ifdef ENTRY_SYS_CPUS
 250 #else
 251                                 halt_processor();
 252 #endif
 253                                 break;
 254
 255                         case IPI_CPU_TEST:
 256 #if (kDEBUG>=100)
 257                                 printk(KERN_DEBUG "CPU%d is alive!\n",this_cpu);
 258 #endif /* kDEBUG */
 259                                 break;
 260
 261                         default:
 262                                 printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
 263                                         this_cpu, which);
 264                                 return IRQ_NONE;
 265                         } /* Switch */
 266                 } /* while (ops) */
 267         }
 268         return IRQ_HANDLED;
 269 }
 270
 271
 272 static inline void
 273 ipi_send(int cpu, enum ipi_message_type op)
 274 {
 275         struct cpuinfo_parisc *p = &cpu_data[cpu];
 276         unsigned long flags;
 277
 278         spin_lock_irqsave(&(p->lock),flags);
 279         p->pending_ipi |= 1 << op;
 280         gsc_writel(IPI_IRQ - CPU_IRQ_BASE, cpu_data[cpu].hpa);
 281         spin_unlock_irqrestore(&(p->lock),flags);
 282 }
 283
 284
 285 static inline void
 286 send_IPI_single(int dest_cpu, enum ipi_message_type op)
 287 {
 288         if (dest_cpu == NO_PROC_ID) {
 289                 BUG();
 290                 return;
 291         }
 292
 293         ipi_send(dest_cpu, op);
 294 }
 295
 296 static inline void
 297 send_IPI_allbutself(enum ipi_message_type op)
 298 {
 299         int i;
 300
 301         for (i = 0; i < NR_CPUS; i++) {
 302                 if (cpu_online(i) && i != smp_processor_id())
 303                         send_IPI_single(i, op);
 304         }
 305 }
 306
 307
 308 inline void
 309 smp_send_stop(void)     { send_IPI_allbutself(IPI_CPU_STOP); }
 310
 311 static inline void
 312 smp_send_start(void)    { send_IPI_allbutself(IPI_CPU_START); }
 313
 314 void
 315 smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
 316
 317 void
 318 smp_send_all_nop(void)
 319 {
 320         send_IPI_allbutself(IPI_NOP);
 321 }
 322
 323
 324 /**
 325  * Run a function on all other CPUs.
 326  *  <func>      The function to run. This must be fast and non-blocking.
 327  *  <info>      An arbitrary pointer to pass to the function.
 328  *  <retry>     If true, keep retrying until ready.
 329  *  <wait>      If true, wait until function has completed on other CPUs.
 330  *  [RETURNS]   0 on success, else a negative status code.
 331  *
 332  * Does not return until remote CPUs are nearly ready to execute <func>
 333  * or have executed.
 334  */
 335
 336 int
 337 smp_call_function (void (*func) (void *info), void *info, int retry, int wait)
 338 {
 339         struct smp_call_struct data;
 340         unsigned long timeout;
 341         static DEFINE_SPINLOCK(lock);
 342         int retries = 0;
 343
 344         if (num_online_cpus() < 2)
 345                 return 0;
 346
 347         /* Can deadlock when called with interrupts disabled */
 348         WARN_ON(irqs_disabled());
 349
 350         /* can also deadlock if IPIs are disabled */
 351         WARN_ON((get_eiem() & (1UL<<(CPU_IRQ_MAX - IPI_IRQ))) == 0);
 352
 353
 354         data.func = func;
 355         data.info = info;
 356         data.wait = wait;
 357         atomic_set(&data.unstarted_count, num_online_cpus() - 1);
 358         atomic_set(&data.unfinished_count, num_online_cpus() - 1);
 359
 360         if (retry) {
 361                 spin_lock (&lock);
 362                 while (smp_call_function_data != 0)
 363                         barrier();
 364         }
 365         else {
 366                 spin_lock (&lock);
 367                 if (smp_call_function_data) {
 368                         spin_unlock (&lock);
 369                         return -EBUSY;
 370                 }
 371         }
 372
 373         smp_call_function_data = &data;
 374         spin_unlock (&lock);
 375
 376         /*  Send a message to all other CPUs and wait for them to respond  */
 377         send_IPI_allbutself(IPI_CALL_FUNC);
 378
 379  retry:
 380         /*  Wait for response  */
 381         timeout = jiffies + HZ;
 382         while ( (atomic_read (&data.unstarted_count) > 0) &&
 383                 time_before (jiffies, timeout) )
 384                 barrier ();
 385
 386         if (atomic_read (&data.unstarted_count) > 0) {
 387                 printk(KERN_CRIT "SMP CALL FUNCTION TIMED OUT! (cpu=%d), try %d\n",
 388                       smp_processor_id(), ++retries);
 389                 goto retry;
 390         }
 391         /* We either got one or timed out. Release the lock */
 392
 393         mb();
 394         smp_call_function_data = NULL;
 395
 396         while (wait && atomic_read (&data.unfinished_count) > 0)
 397                         barrier ();
 398
 399         return 0;
 400 }
 401
 402 EXPORT_SYMBOL(smp_call_function);
 403
 404 /*
 405  * Flush all other CPU's tlb and then mine.  Do this with on_each_cpu()
 406  * as we want to ensure all TLB's flushed before proceeding.
 407  */
 408
 409 extern void flush_tlb_all_local(void);
 410
 411 void
 412 smp_flush_tlb_all(void)
 413 {
 414         on_each_cpu((void (*)(void *))flush_tlb_all_local, NULL, 1, 1);
 415 }
 416
 417
 418 void
 419 smp_do_timer(struct pt_regs *regs)
 420 {
 421         int cpu = smp_processor_id();
 422         struct cpuinfo_parisc *data = &cpu_data[cpu];
 423
 424         if (!--data->prof_counter) {
 425                 data->prof_counter = data->prof_multiplier;
 426                 update_process_times(user_mode(regs));
 427         }
 428 }
 429
 430 /*
 431  * Called by secondaries to update state and initialize CPU registers.
 432  */
 433 static void __init
 434 smp_cpu_init(int cpunum)
 435 {
 436         extern int init_per_cpu(int);  /* arch/parisc/kernel/setup.c */
 437         extern void init_IRQ(void);    /* arch/parisc/kernel/irq.c */
 438
 439         /* Set modes and Enable floating point coprocessor */
 440         (void) init_per_cpu(cpunum);
 441
 442         disable_sr_hashing();
 443
 444         mb();
 445
 446         /* Well, support 2.4 linux scheme as well. */
 447         if (cpu_test_and_set(cpunum, cpu_online_map))
 448         {
 449                 extern void machine_halt(void); /* arch/parisc.../process.c */
 450
 451                 printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
 452                 machine_halt();
 453         }
 454
 455         /* Initialise the idle task for this CPU */
 456         atomic_inc(&init_mm.mm_count);
 457         current->active_mm = &init_mm;
 458         if(current->mm)
 459                 BUG();
 460         enter_lazy_tlb(&init_mm, current);
 461
 462         init_IRQ();   /* make sure no IRQ's are enabled or pending */
 463 }
 464
 465
 466 /*
 467  * Slaves start using C here. Indirectly called from smp_slave_stext.
 468  * Do what start_kernel() and main() do for boot strap processor (aka monarch)
 469  */
 470 void __init smp_callin(void)
 471 {
 472         int slave_id = cpu_now_booting;
 473 #if 0
 474         void *istack;
 475 #endif
 476
 477         smp_cpu_init(slave_id);
 478         preempt_disable();
 479
 480 #if 0   /* NOT WORKING YET - see entry.S */
 481         istack = (void *)__get_free_pages(GFP_KERNEL,ISTACK_ORDER);
 482         if (istack == NULL) {
 483             printk(KERN_CRIT "Failed to allocate interrupt stack for cpu %d\n",slave_id);
 484             BUG();
 485         }
 486         mtctl(istack,31);
 487 #endif
 488
 489         flush_cache_all_local(); /* start with known state */
 490         flush_tlb_all_local();
 491
 492         local_irq_enable();  /* Interrupts have been off until now */
 493
 494         cpu_idle();      /* Wait for timer to schedule some work */
 495
 496         /* NOTREACHED */
 497         panic("smp_callin() AAAAaaaaahhhh....\n");
 498 }
 499
 500 /*
 501  * Bring one cpu online.
 502  */
 503 int __init smp_boot_one_cpu(int cpuid)
 504 {
 505         struct task_struct *idle;
 506         long timeout;
 507
 508         /*
 509          * Create an idle task for this CPU.  Note the address wed* give
 510          * to kernel_thread is irrelevant -- it's going to start
 511          * where OS_BOOT_RENDEVZ vector in SAL says to start.  But
 512          * this gets all the other task-y sort of data structures set
 513          * up like we wish.   We need to pull the just created idle task
 514          * off the run queue and stuff it into the init_tasks[] array.
 515          * Sheesh . . .
 516          */
 517
 518         idle = fork_idle(cpuid);
 519         if (IS_ERR(idle))
 520                 panic("SMP: fork failed for CPU:%d", cpuid);
 521
 522         idle->thread_info->cpu = cpuid;
 523
 524         /* Let _start know what logical CPU we're booting
 525         ** (offset into init_tasks[],cpu_data[])
 526         */
 527         cpu_now_booting = cpuid;
 528
 529         /*
 530         ** boot strap code needs to know the task address since
 531         ** it also contains the process stack.
 532         */
 533         smp_init_current_idle_task = idle ;
 534         mb();
 535
 536         printk("Releasing cpu %d now, hpa=%lx\n", cpuid, cpu_data[cpuid].hpa);
 537
 538         /*
 539         ** This gets PDC to release the CPU from a very tight loop.
 540         **
 541         ** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
 542         ** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which
 543         ** is executed after receiving the rendezvous signal (an interrupt to
 544         ** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the
 545         ** contents of memory are valid."
 546         */
 547         gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, cpu_data[cpuid].hpa);
 548         mb();
 549
 550         /*
 551          * OK, wait a bit for that CPU to finish staggering about.
 552          * Slave will set a bit when it reaches smp_cpu_init().
 553          * Once the "monarch CPU" sees the bit change, it can move on.
 554          */
 555         for (timeout = 0; timeout < 10000; timeout++) {
 556                 if(cpu_online(cpuid)) {
 557                         /* Which implies Slave has started up */
 558                         cpu_now_booting = 0;
 559                         smp_init_current_idle_task = NULL;
 560                         goto alive ;
 561                 }
 562                 udelay(100);
 563                 barrier();
 564         }
 565
 566         put_task_struct(idle);
 567         idle = NULL;
 568
 569         printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
 570         return -1;
 571
 572 alive:
 573         /* Remember the Slave data */
 574 #if (kDEBUG>=100)
 575         printk(KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
 576                 cpuid, timeout * 100);
 577 #endif /* kDEBUG */
 578 #ifdef ENTRY_SYS_CPUS
 579         cpu_data[cpuid].state = STATE_RUNNING;
 580 #endif
 581         return 0;
 582 }
 583
 584 void __devinit smp_prepare_boot_cpu(void)
 585 {
 586         int bootstrap_processor=cpu_data[0].cpuid;      /* CPU ID of BSP */
 587
 588 #ifdef ENTRY_SYS_CPUS
 589         cpu_data[0].state = STATE_RUNNING;
 590 #endif
 591
 592         /* Setup BSP mappings */
 593         printk("SMP: bootstrap CPU ID is %d\n",bootstrap_processor);
 594
 595         cpu_set(bootstrap_processor, cpu_online_map);
 596         cpu_set(bootstrap_processor, cpu_present_map);
 597 }
 598
 599
 600
 601 /*
 602 ** inventory.c:do_inventory() hasn't yet been run and thus we
 603 ** don't 'discover' the additional CPU's until later.
 604 */
 605 void __init smp_prepare_cpus(unsigned int max_cpus)
 606 {
 607         cpus_clear(cpu_present_map);
 608         cpu_set(0, cpu_present_map);
 609
 610         parisc_max_cpus = max_cpus;
 611         if (!max_cpus)
 612                 printk(KERN_INFO "SMP mode deactivated.\n");
 613 }
 614
 615
 616 void smp_cpus_done(unsigned int cpu_max)
 617 {
 618         return;
 619 }
 620
 621
 622 int __devinit __cpu_up(unsigned int cpu)
 623 {
 624         if (cpu != 0 && cpu < parisc_max_cpus)
 625                 smp_boot_one_cpu(cpu);
 626
 627         return cpu_online(cpu) ? 0 : -ENOSYS;
 628 }
 629
 630
 631
 632 #ifdef ENTRY_SYS_CPUS
 633 /* Code goes along with:
 634 **    entry.s:        ENTRY_NAME(sys_cpus)   / * 215, for cpu stat * /
 635 */
 636 int sys_cpus(int argc, char **argv)
 637 {
 638         int i,j=0;
 639         extern int current_pid(int cpu);
 640
 641         if( argc > 2 ) {
 642                 printk("sys_cpus:Only one argument supported\n");
 643                 return (-1);
 644         }
 645         if ( argc == 1 ){
 646
 647 #ifdef DUMP_MORE_STATE
 648                 for(i=0; i<NR_CPUS; i++) {
 649                         int cpus_per_line = 4;
 650                         if(cpu_online(i)) {
 651                                 if (j++ % cpus_per_line)
 652                                         printk(" %3d",i);
 653                                 else
 654                                         printk("\n %3d",i);
 655                         }
 656                 }
 657                 printk("\n");
 658 #else
 659                 printk("\n 0\n");
 660 #endif
 661         } else if((argc==2) && !(strcmp(argv[1],"-l"))) {
 662                 printk("\nCPUSTATE  TASK CPUNUM CPUID HARDCPU(HPA)\n");
 663 #ifdef DUMP_MORE_STATE
 664                 for(i=0;i<NR_CPUS;i++) {
 665                         if (!cpu_online(i))
 666                                 continue;
 667                         if (cpu_data[i].cpuid != NO_PROC_ID) {
 668                                 switch(cpu_data[i].state) {
 669                                         case STATE_RENDEZVOUS:
 670                                                 printk("RENDEZVS ");
 671                                                 break;
 672                                         case STATE_RUNNING:
 673                                                 printk((current_pid(i)!=0) ? "RUNNING  " : "IDLING   ");
 674                                                 break;
 675                                         case STATE_STOPPED:
 676                                                 printk("STOPPED  ");
 677                                                 break;
 678                                         case STATE_HALTED:
 679                                                 printk("HALTED   ");
 680                                                 break;
 681                                         default:
 682                                                 printk("%08x?", cpu_data[i].state);
 683                                                 break;
 684                                 }
 685                                 if(cpu_online(i)) {
 686                                         printk(" %4d",current_pid(i));
 687                                 }
 688                                 printk(" %6d",cpu_number_map(i));
 689                                 printk(" %5d",i);
 690                                 printk(" 0x%lx\n",cpu_data[i].hpa);
 691                         }
 692                 }
 693 #else
 694                 printk("\n%s  %4d      0     0 --------",
 695                         (current->pid)?"RUNNING ": "IDLING  ",current->pid);
 696 #endif
 697         } else if ((argc==2) && !(strcmp(argv[1],"-s"))) {
 698 #ifdef DUMP_MORE_STATE
 699                 printk("\nCPUSTATE   CPUID\n");
 700                 for (i=0;i<NR_CPUS;i++) {
 701                         if (!cpu_online(i))
 702                                 continue;
 703                         if (cpu_data[i].cpuid != NO_PROC_ID) {
 704                                 switch(cpu_data[i].state) {
 705                                         case STATE_RENDEZVOUS:
 706                                                 printk("RENDEZVS");break;
 707                                         case STATE_RUNNING:
 708                                                 printk((current_pid(i)!=0) ? "RUNNING " : "IDLING");
 709                                                 break;
 710                                         case STATE_STOPPED:
 711                                                 printk("STOPPED ");break;
 712                                         case STATE_HALTED:
 713                                                 printk("HALTED  ");break;
 714                                         default:
 715                                 }
 716                                 printk("  %5d\n",i);
 717                         }
 718                 }
 719 #else
 720                 printk("\n%s    CPU0",(current->pid==0)?"RUNNING ":"IDLING  ");
 721 #endif
 722         } else {
 723                 printk("sys_cpus:Unknown request\n");
 724                 return (-1);
 725         }
 726         return 0;
 727 }
 728 #endif /* ENTRY_SYS_CPUS */
 729
 730 #ifdef CONFIG_PROC_FS
 731 int __init
 732 setup_profiling_timer(unsigned int multiplier)
 733 {
 734         return -EINVAL;
 735 }
 736 #endif