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 static int parisc_max_cpus = 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 = CPU_MASK_NONE;       /* Bitmap of online CPUs */
  75 cpumask_t cpu_possible_map = 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                         switch (which) {
 185                         case IPI_RESCHEDULE:
 186 #if (kDEBUG>=100)
 187                                 printk(KERN_DEBUG "CPU%d IPI_RESCHEDULE\n",this_cpu);
 188 #endif /* kDEBUG */
 189                                 ops &= ~(1 << IPI_RESCHEDULE);
 190                                 /*
 191                                  * Reschedule callback.  Everything to be
 192                                  * done is done by the interrupt return path.
 193                                  */
 194                                 break;
 195
 196                         case IPI_CALL_FUNC:
 197 #if (kDEBUG>=100)
 198                                 printk(KERN_DEBUG "CPU%d IPI_CALL_FUNC\n",this_cpu);
 199 #endif /* kDEBUG */
 200                                 ops &= ~(1 << IPI_CALL_FUNC);
 201                                 {
 202                                         volatile struct smp_call_struct *data;
 203                                         void (*func)(void *info);
 204                                         void *info;
 205                                         int wait;
 206
 207                                         data = smp_call_function_data;
 208                                         func = data->func;
 209                                         info = data->info;
 210                                         wait = data->wait;
 211
 212                                         mb();
 213                                         atomic_dec ((atomic_t *)&data->unstarted_count);
 214
 215                                         /* At this point, *data can't
 216                                          * be relied upon.
 217                                          */
 218
 219                                         (*func)(info);
 220
 221                                         /* Notify the sending CPU that the
 222                                          * task is done.
 223                                          */
 224                                         mb();
 225                                         if (wait)
 226                                                 atomic_dec ((atomic_t *)&data->unfinished_count);
 227                                 }
 228                                 break;
 229
 230                         case IPI_CPU_START:
 231 #if (kDEBUG>=100)
 232                                 printk(KERN_DEBUG "CPU%d IPI_CPU_START\n",this_cpu);
 233 #endif /* kDEBUG */
 234                                 ops &= ~(1 << IPI_CPU_START);
 235 #ifdef ENTRY_SYS_CPUS
 236                                 p->state = STATE_RUNNING;
 237 #endif
 238                                 break;
 239
 240                         case IPI_CPU_STOP:
 241 #if (kDEBUG>=100)
 242                                 printk(KERN_DEBUG "CPU%d IPI_CPU_STOP\n",this_cpu);
 243 #endif /* kDEBUG */
 244                                 ops &= ~(1 << IPI_CPU_STOP);
 245 #ifdef ENTRY_SYS_CPUS
 246 #else
 247                                 halt_processor();
 248 #endif
 249                                 break;
 250
 251                         case IPI_CPU_TEST:
 252 #if (kDEBUG>=100)
 253                                 printk(KERN_DEBUG "CPU%d is alive!\n",this_cpu);
 254 #endif /* kDEBUG */
 255                                 ops &= ~(1 << IPI_CPU_TEST);
 256                                 break;
 257
 258                         default:
 259                                 printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
 260                                         this_cpu, which);
 261                                 ops &= ~(1 << which);
 262                                 return IRQ_NONE;
 263                         } /* Switch */
 264                 } /* while (ops) */
 265         }
 266         return IRQ_HANDLED;
 267 }
 268
 269
 270 static inline void
 271 ipi_send(int cpu, enum ipi_message_type op)
 272 {
 273         struct cpuinfo_parisc *p = &cpu_data[cpu];
 274         unsigned long flags;
 275
 276         spin_lock_irqsave(&(p->lock),flags);
 277         p->pending_ipi |= 1 << op;
 278         gsc_writel(IPI_IRQ - CPU_IRQ_BASE, cpu_data[cpu].hpa);
 279         spin_unlock_irqrestore(&(p->lock),flags);
 280 }
 281
 282
 283 static inline void
 284 send_IPI_single(int dest_cpu, enum ipi_message_type op)
 285 {
 286         if (dest_cpu == NO_PROC_ID) {
 287                 BUG();
 288                 return;
 289         }
 290
 291         ipi_send(dest_cpu, op);
 292 }
 293
 294 static inline void
 295 send_IPI_allbutself(enum ipi_message_type op)
 296 {
 297         int i;
 298
 299         for (i = 0; i < NR_CPUS; i++) {
 300                 if (cpu_online(i) && i != smp_processor_id())
 301                         send_IPI_single(i, op);
 302         }
 303 }
 304
 305
 306 inline void
 307 smp_send_stop(void)     { send_IPI_allbutself(IPI_CPU_STOP); }
 308
 309 static inline void
 310 smp_send_start(void)    { send_IPI_allbutself(IPI_CPU_START); }
 311
 312 void
 313 smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
 314
 315
 316 /**
 317  * Run a function on all other CPUs.
 318  *  <func>      The function to run. This must be fast and non-blocking.
 319  *  <info>      An arbitrary pointer to pass to the function.
 320  *  <retry>     If true, keep retrying until ready.
 321  *  <wait>      If true, wait until function has completed on other CPUs.
 322  *  [RETURNS]   0 on success, else a negative status code.
 323  *
 324  * Does not return until remote CPUs are nearly ready to execute <func>
 325  * or have executed.
 326  */
 327
 328 int
 329 smp_call_function (void (*func) (void *info), void *info, int retry, int wait)
 330 {
 331         struct smp_call_struct data;
 332         unsigned long timeout;
 333         static DEFINE_SPINLOCK(lock);
 334         int retries = 0;
 335
 336         if (num_online_cpus() < 2)
 337                 return 0;
 338
 339         /* Can deadlock when called with interrupts disabled */
 340         WARN_ON(irqs_disabled());
 341
 342         data.func = func;
 343         data.info = info;
 344         data.wait = wait;
 345         atomic_set(&data.unstarted_count, num_online_cpus() - 1);
 346         atomic_set(&data.unfinished_count, num_online_cpus() - 1);
 347
 348         if (retry) {
 349                 spin_lock (&lock);
 350                 while (smp_call_function_data != 0)
 351                         barrier();
 352         }
 353         else {
 354                 spin_lock (&lock);
 355                 if (smp_call_function_data) {
 356                         spin_unlock (&lock);
 357                         return -EBUSY;
 358                 }
 359         }
 360
 361         smp_call_function_data = &data;
 362         spin_unlock (&lock);
 363
 364         /*  Send a message to all other CPUs and wait for them to respond  */
 365         send_IPI_allbutself(IPI_CALL_FUNC);
 366
 367  retry:
 368         /*  Wait for response  */
 369         timeout = jiffies + HZ;
 370         while ( (atomic_read (&data.unstarted_count) > 0) &&
 371                 time_before (jiffies, timeout) )
 372                 barrier ();
 373
 374         if (atomic_read (&data.unstarted_count) > 0) {
 375                 printk(KERN_CRIT "SMP CALL FUNCTION TIMED OUT! (cpu=%d), try %d\n",
 376                       smp_processor_id(), ++retries);
 377                 goto retry;
 378         }
 379         /* We either got one or timed out. Release the lock */
 380
 381         mb();
 382         smp_call_function_data = NULL;
 383
 384         while (wait && atomic_read (&data.unfinished_count) > 0)
 385                         barrier ();
 386
 387         return 0;
 388 }
 389
 390 EXPORT_SYMBOL(smp_call_function);
 391
 392 /*
 393  * Flush all other CPU's tlb and then mine.  Do this with on_each_cpu()
 394  * as we want to ensure all TLB's flushed before proceeding.
 395  */
 396
 397 extern void flush_tlb_all_local(void);
 398
 399 void
 400 smp_flush_tlb_all(void)
 401 {
 402         on_each_cpu((void (*)(void *))flush_tlb_all_local, NULL, 1, 1);
 403 }
 404
 405
 406 void
 407 smp_do_timer(struct pt_regs *regs)
 408 {
 409         int cpu = smp_processor_id();
 410         struct cpuinfo_parisc *data = &cpu_data[cpu];
 411
 412         if (!--data->prof_counter) {
 413                 data->prof_counter = data->prof_multiplier;
 414                 update_process_times(user_mode(regs));
 415         }
 416 }
 417
 418 /*
 419  * Called by secondaries to update state and initialize CPU registers.
 420  */
 421 static void __init
 422 smp_cpu_init(int cpunum)
 423 {
 424         extern int init_per_cpu(int);  /* arch/parisc/kernel/setup.c */
 425         extern void init_IRQ(void);    /* arch/parisc/kernel/irq.c */
 426
 427         /* Set modes and Enable floating point coprocessor */
 428         (void) init_per_cpu(cpunum);
 429
 430         disable_sr_hashing();
 431
 432         mb();
 433
 434         /* Well, support 2.4 linux scheme as well. */
 435         if (cpu_test_and_set(cpunum, cpu_online_map))
 436         {
 437                 extern void machine_halt(void); /* arch/parisc.../process.c */
 438
 439                 printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
 440                 machine_halt();
 441         }
 442
 443         /* Initialise the idle task for this CPU */
 444         atomic_inc(&init_mm.mm_count);
 445         current->active_mm = &init_mm;
 446         if(current->mm)
 447                 BUG();
 448         enter_lazy_tlb(&init_mm, current);
 449
 450         init_IRQ();   /* make sure no IRQ's are enabled or pending */
 451 }
 452
 453
 454 /*
 455  * Slaves start using C here. Indirectly called from smp_slave_stext.
 456  * Do what start_kernel() and main() do for boot strap processor (aka monarch)
 457  */
 458 void __init smp_callin(void)
 459 {
 460         int slave_id = cpu_now_booting;
 461 #if 0
 462         void *istack;
 463 #endif
 464
 465         smp_cpu_init(slave_id);
 466
 467 #if 0   /* NOT WORKING YET - see entry.S */
 468         istack = (void *)__get_free_pages(GFP_KERNEL,ISTACK_ORDER);
 469         if (istack == NULL) {
 470             printk(KERN_CRIT "Failed to allocate interrupt stack for cpu %d\n",slave_id);
 471             BUG();
 472         }
 473         mtctl(istack,31);
 474 #endif
 475
 476         flush_cache_all_local(); /* start with known state */
 477         flush_tlb_all_local();
 478
 479         local_irq_enable();  /* Interrupts have been off until now */
 480
 481         cpu_idle();      /* Wait for timer to schedule some work */
 482
 483         /* NOTREACHED */
 484         panic("smp_callin() AAAAaaaaahhhh....\n");
 485 }
 486
 487 /*
 488  * Bring one cpu online.
 489  */
 490 int __init smp_boot_one_cpu(int cpuid)
 491 {
 492         struct task_struct *idle;
 493         long timeout;
 494
 495         /*
 496          * Create an idle task for this CPU.  Note the address wed* give
 497          * to kernel_thread is irrelevant -- it's going to start
 498          * where OS_BOOT_RENDEVZ vector in SAL says to start.  But
 499          * this gets all the other task-y sort of data structures set
 500          * up like we wish.   We need to pull the just created idle task
 501          * off the run queue and stuff it into the init_tasks[] array.
 502          * Sheesh . . .
 503          */
 504
 505         idle = fork_idle(cpuid);
 506         if (IS_ERR(idle))
 507                 panic("SMP: fork failed for CPU:%d", cpuid);
 508
 509         idle->thread_info->cpu = cpuid;
 510
 511         /* Let _start know what logical CPU we're booting
 512         ** (offset into init_tasks[],cpu_data[])
 513         */
 514         cpu_now_booting = cpuid;
 515
 516         /*
 517         ** boot strap code needs to know the task address since
 518         ** it also contains the process stack.
 519         */
 520         smp_init_current_idle_task = idle ;
 521         mb();
 522
 523         printk("Releasing cpu %d now, hpa=%lx\n", cpuid, cpu_data[cpuid].hpa);
 524
 525         /*
 526         ** This gets PDC to release the CPU from a very tight loop.
 527         **
 528         ** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
 529         ** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which
 530         ** is executed after receiving the rendezvous signal (an interrupt to
 531         ** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the
 532         ** contents of memory are valid."
 533         */
 534         gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, cpu_data[cpuid].hpa);
 535         mb();
 536
 537         /*
 538          * OK, wait a bit for that CPU to finish staggering about.
 539          * Slave will set a bit when it reaches smp_cpu_init().
 540          * Once the "monarch CPU" sees the bit change, it can move on.
 541          */
 542         for (timeout = 0; timeout < 10000; timeout++) {
 543                 if(cpu_online(cpuid)) {
 544                         /* Which implies Slave has started up */
 545                         cpu_now_booting = 0;
 546                         smp_init_current_idle_task = NULL;
 547                         goto alive ;
 548                 }
 549                 udelay(100);
 550                 barrier();
 551         }
 552
 553         put_task_struct(idle);
 554         idle = NULL;
 555
 556         printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
 557         return -1;
 558
 559 alive:
 560         /* Remember the Slave data */
 561 #if (kDEBUG>=100)
 562         printk(KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
 563                 cpuid, timeout * 100);
 564 #endif /* kDEBUG */
 565 #ifdef ENTRY_SYS_CPUS
 566         cpu_data[cpuid].state = STATE_RUNNING;
 567 #endif
 568         return 0;
 569 }
 570
 571 void __devinit smp_prepare_boot_cpu(void)
 572 {
 573         int bootstrap_processor=cpu_data[0].cpuid;      /* CPU ID of BSP */
 574
 575 #ifdef ENTRY_SYS_CPUS
 576         cpu_data[0].state = STATE_RUNNING;
 577 #endif
 578
 579         /* Setup BSP mappings */
 580         printk("SMP: bootstrap CPU ID is %d\n",bootstrap_processor);
 581
 582         cpu_set(bootstrap_processor, cpu_online_map);
 583         cpu_set(bootstrap_processor, cpu_present_map);
 584 }
 585
 586
 587
 588 /*
 589 ** inventory.c:do_inventory() hasn't yet been run and thus we
 590 ** don't 'discover' the additional CPU's until later.
 591 */
 592 void __init smp_prepare_cpus(unsigned int max_cpus)
 593 {
 594         cpus_clear(cpu_present_map);
 595         cpu_set(0, cpu_present_map);
 596
 597         parisc_max_cpus = max_cpus;
 598         if (!max_cpus)
 599                 printk(KERN_INFO "SMP mode deactivated.\n");
 600 }
 601
 602
 603 void smp_cpus_done(unsigned int cpu_max)
 604 {
 605         return;
 606 }
 607
 608
 609 int __devinit __cpu_up(unsigned int cpu)
 610 {
 611         if (cpu != 0 && cpu < parisc_max_cpus)
 612                 smp_boot_one_cpu(cpu);
 613
 614         return cpu_online(cpu) ? 0 : -ENOSYS;
 615 }
 616
 617
 618
 619 #ifdef ENTRY_SYS_CPUS
 620 /* Code goes along with:
 621 **    entry.s:        ENTRY_NAME(sys_cpus)   / * 215, for cpu stat * /
 622 */
 623 int sys_cpus(int argc, char **argv)
 624 {
 625         int i,j=0;
 626         extern int current_pid(int cpu);
 627
 628         if( argc > 2 ) {
 629                 printk("sys_cpus:Only one argument supported\n");
 630                 return (-1);
 631         }
 632         if ( argc == 1 ){
 633
 634 #ifdef DUMP_MORE_STATE
 635                 for(i=0; i<NR_CPUS; i++) {
 636                         int cpus_per_line = 4;
 637                         if(cpu_online(i)) {
 638                                 if (j++ % cpus_per_line)
 639                                         printk(" %3d",i);
 640                                 else
 641                                         printk("\n %3d",i);
 642                         }
 643                 }
 644                 printk("\n");
 645 #else
 646                 printk("\n 0\n");
 647 #endif
 648         } else if((argc==2) && !(strcmp(argv[1],"-l"))) {
 649                 printk("\nCPUSTATE  TASK CPUNUM CPUID HARDCPU(HPA)\n");
 650 #ifdef DUMP_MORE_STATE
 651                 for(i=0;i<NR_CPUS;i++) {
 652                         if (!cpu_online(i))
 653                                 continue;
 654                         if (cpu_data[i].cpuid != NO_PROC_ID) {
 655                                 switch(cpu_data[i].state) {
 656                                         case STATE_RENDEZVOUS:
 657                                                 printk("RENDEZVS ");
 658                                                 break;
 659                                         case STATE_RUNNING:
 660                                                 printk((current_pid(i)!=0) ? "RUNNING  " : "IDLING   ");
 661                                                 break;
 662                                         case STATE_STOPPED:
 663                                                 printk("STOPPED  ");
 664                                                 break;
 665                                         case STATE_HALTED:
 666                                                 printk("HALTED   ");
 667                                                 break;
 668                                         default:
 669                                                 printk("%08x?", cpu_data[i].state);
 670                                                 break;
 671                                 }
 672                                 if(cpu_online(i)) {
 673                                         printk(" %4d",current_pid(i));
 674                                 }
 675                                 printk(" %6d",cpu_number_map(i));
 676                                 printk(" %5d",i);
 677                                 printk(" 0x%lx\n",cpu_data[i].hpa);
 678                         }
 679                 }
 680 #else
 681                 printk("\n%s  %4d      0     0 --------",
 682                         (current->pid)?"RUNNING ": "IDLING  ",current->pid);
 683 #endif
 684         } else if ((argc==2) && !(strcmp(argv[1],"-s"))) {
 685 #ifdef DUMP_MORE_STATE
 686                 printk("\nCPUSTATE   CPUID\n");
 687                 for (i=0;i<NR_CPUS;i++) {
 688                         if (!cpu_online(i))
 689                                 continue;
 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