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