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