arch/m32r/kernel/smp.c

   1 /*
   2  *  linux/arch/m32r/kernel/smp.c
   3  *
   4  *  M32R SMP support routines.
   5  *
   6  *  Copyright (c) 2001, 2002  Hitoshi Yamamoto
   7  *
   8  *  Taken from i386 version.
   9  *    (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
  10  *    (c) 1998-99, 2000 Ingo Molnar <mingo@redhat.com>
  11  *
  12  *  This code is released under the GNU General Public License version 2 or
  13  *  later.
  14  */
  15
  16 #undef DEBUG_SMP
  17
  18 #include <linux/irq.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/sched.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/mm.h>
  23 #include <linux/smp.h>
  24 #include <linux/profile.h>
  25 #include <linux/cpu.h>
  26
  27 #include <asm/cacheflush.h>
  28 #include <asm/pgalloc.h>
  29 #include <asm/atomic.h>
  30 #include <asm/io.h>
  31 #include <asm/mmu_context.h>
  32 #include <asm/m32r.h>
  33 #include <asm/tlbflush.h>
  34
  35 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
  36 /* Data structures and variables                                             */
  37 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
  38
  39 /*
  40  * For flush_cache_all()
  41  */
  42 static DEFINE_SPINLOCK(flushcache_lock);
  43 static volatile unsigned long flushcache_cpumask = 0;
  44
  45 /*
  46  * For flush_tlb_others()
  47  */
  48 static volatile cpumask_t flush_cpumask;
  49 static struct mm_struct *flush_mm;
  50 static struct vm_area_struct *flush_vma;
  51 static volatile unsigned long flush_va;
  52 static DEFINE_SPINLOCK(tlbstate_lock);
  53 #define FLUSH_ALL 0xffffffff
  54
  55 DECLARE_PER_CPU(int, prof_multiplier);
  56 DECLARE_PER_CPU(int, prof_old_multiplier);
  57 DECLARE_PER_CPU(int, prof_counter);
  58
  59 extern spinlock_t ipi_lock[];
  60
  61 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
  62 /* Function Prototypes                                                       */
  63 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
  64
  65 void smp_reschedule_interrupt(void);
  66 void smp_flush_cache_all_interrupt(void);
  67
  68 static void flush_tlb_all_ipi(void *);
  69 static void flush_tlb_others(cpumask_t, struct mm_struct *,
  70         struct vm_area_struct *, unsigned long);
  71
  72 void smp_invalidate_interrupt(void);
  73
  74 static void stop_this_cpu(void *);
  75
  76 void smp_ipi_timer_interrupt(struct pt_regs *);
  77 void smp_local_timer_interrupt(void);
  78
  79 static void send_IPI_allbutself(int, int);
  80 static void send_IPI_mask(const struct cpumask *, int, int);
  81
  82 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
  83 /* Rescheduling request Routines                                             */
  84 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
  85
  86 /*==========================================================================*
  87  * Name:         smp_send_reschedule
  88  *
  89  * Description:  This routine requests other CPU to execute rescheduling.
  90  *               1.Send 'RESCHEDULE_IPI' to other CPU.
  91  *                 Request other CPU to execute 'smp_reschedule_interrupt()'.
  92  *
  93  * Born on Date: 2002.02.05
  94  *
  95  * Arguments:    cpu_id - Target CPU ID
  96  *
  97  * Returns:      void (cannot fail)
  98  *
  99  * Modification log:
 100  * Date       Who Description
 101  * ---------- --- --------------------------------------------------------
 102  *
 103  *==========================================================================*/
 104 void smp_send_reschedule(int cpu_id)
 105 {
 106         WARN_ON(cpu_is_offline(cpu_id));
 107         send_IPI_mask(cpumask_of(cpu_id), RESCHEDULE_IPI, 1);
 108 }
 109
 110 /*==========================================================================*
 111  * Name:         smp_reschedule_interrupt
 112  *
 113  * Description:  This routine executes on CPU which received
 114  *               'RESCHEDULE_IPI'.
 115  *
 116  * Born on Date: 2002.02.05
 117  *
 118  * Arguments:    NONE
 119  *
 120  * Returns:      void (cannot fail)
 121  *
 122  * Modification log:
 123  * Date       Who Description
 124  * ---------- --- --------------------------------------------------------
 125  *
 126  *==========================================================================*/
 127 void smp_reschedule_interrupt(void)
 128 {
 129         scheduler_ipi();
 130 }
 131
 132 /*==========================================================================*
 133  * Name:         smp_flush_cache_all
 134  *
 135  * Description:  This routine sends a 'INVALIDATE_CACHE_IPI' to all other
 136  *               CPUs in the system.
 137  *
 138  * Born on Date: 2003-05-28
 139  *
 140  * Arguments:    NONE
 141  *
 142  * Returns:      void (cannot fail)
 143  *
 144  * Modification log:
 145  * Date       Who Description
 146  * ---------- --- --------------------------------------------------------
 147  *
 148  *==========================================================================*/
 149 void smp_flush_cache_all(void)
 150 {
 151         cpumask_t cpumask;
 152         unsigned long *mask;
 153
 154         preempt_disable();
 155         cpumask_copy(&cpumask, cpu_online_mask);
 156         cpumask_clear_cpu(smp_processor_id(), &cpumask);
 157         spin_lock(&flushcache_lock);
 158         mask=cpumask_bits(&cpumask);
 159         atomic_set_mask(*mask, (atomic_t *)&flushcache_cpumask);
 160         send_IPI_mask(&cpumask, INVALIDATE_CACHE_IPI, 0);
 161         _flush_cache_copyback_all();
 162         while (flushcache_cpumask)
 163                 mb();
 164         spin_unlock(&flushcache_lock);
 165         preempt_enable();
 166 }
 167
 168 void smp_flush_cache_all_interrupt(void)
 169 {
 170         _flush_cache_copyback_all();
 171         clear_bit(smp_processor_id(), &flushcache_cpumask);
 172 }
 173
 174 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 175 /* TLB flush request Routines                                                */
 176 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 177
 178 /*==========================================================================*
 179  * Name:         smp_flush_tlb_all
 180  *
 181  * Description:  This routine flushes all processes TLBs.
 182  *               1.Request other CPU to execute 'flush_tlb_all_ipi()'.
 183  *               2.Execute 'do_flush_tlb_all_local()'.
 184  *
 185  * Born on Date: 2002.02.05
 186  *
 187  * Arguments:    NONE
 188  *
 189  * Returns:      void (cannot fail)
 190  *
 191  * Modification log:
 192  * Date       Who Description
 193  * ---------- --- --------------------------------------------------------
 194  *
 195  *==========================================================================*/
 196 void smp_flush_tlb_all(void)
 197 {
 198         unsigned long flags;
 199
 200         preempt_disable();
 201         local_irq_save(flags);
 202         __flush_tlb_all();
 203         local_irq_restore(flags);
 204         smp_call_function(flush_tlb_all_ipi, NULL, 1);
 205         preempt_enable();
 206 }
 207
 208 /*==========================================================================*
 209  * Name:         flush_tlb_all_ipi
 210  *
 211  * Description:  This routine flushes all local TLBs.
 212  *               1.Execute 'do_flush_tlb_all_local()'.
 213  *
 214  * Born on Date: 2002.02.05
 215  *
 216  * Arguments:    *info - not used
 217  *
 218  * Returns:      void (cannot fail)
 219  *
 220  * Modification log:
 221  * Date       Who Description
 222  * ---------- --- --------------------------------------------------------
 223  *
 224  *==========================================================================*/
 225 static void flush_tlb_all_ipi(void *info)
 226 {
 227         __flush_tlb_all();
 228 }
 229
 230 /*==========================================================================*
 231  * Name:         smp_flush_tlb_mm
 232  *
 233  * Description:  This routine flushes the specified mm context TLB's.
 234  *
 235  * Born on Date: 2002.02.05
 236  *
 237  * Arguments:    *mm - a pointer to the mm struct for flush TLB
 238  *
 239  * Returns:      void (cannot fail)
 240  *
 241  * Modification log:
 242  * Date       Who Description
 243  * ---------- --- --------------------------------------------------------
 244  *
 245  *==========================================================================*/
 246 void smp_flush_tlb_mm(struct mm_struct *mm)
 247 {
 248         int cpu_id;
 249         cpumask_t cpu_mask;
 250         unsigned long *mmc;
 251         unsigned long flags;
 252
 253         preempt_disable();
 254         cpu_id = smp_processor_id();
 255         mmc = &mm->context[cpu_id];
 256         cpumask_copy(&cpu_mask, mm_cpumask(mm));
 257         cpumask_clear_cpu(cpu_id, &cpu_mask);
 258
 259         if (*mmc != NO_CONTEXT) {
 260                 local_irq_save(flags);
 261                 *mmc = NO_CONTEXT;
 262                 if (mm == current->mm)
 263                         activate_context(mm);
 264                 else
 265                         cpumask_clear_cpu(cpu_id, mm_cpumask(mm));
 266                 local_irq_restore(flags);
 267         }
 268         if (!cpumask_empty(&cpu_mask))
 269                 flush_tlb_others(cpu_mask, mm, NULL, FLUSH_ALL);
 270
 271         preempt_enable();
 272 }
 273
 274 /*==========================================================================*
 275  * Name:         smp_flush_tlb_range
 276  *
 277  * Description:  This routine flushes a range of pages.
 278  *
 279  * Born on Date: 2002.02.05
 280  *
 281  * Arguments:    *mm - a pointer to the mm struct for flush TLB
 282  *               start - not used
 283  *               end - not used
 284  *
 285  * Returns:      void (cannot fail)
 286  *
 287  * Modification log:
 288  * Date       Who Description
 289  * ---------- --- --------------------------------------------------------
 290  *
 291  *==========================================================================*/
 292 void smp_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 293         unsigned long end)
 294 {
 295         smp_flush_tlb_mm(vma->vm_mm);
 296 }
 297
 298 /*==========================================================================*
 299  * Name:         smp_flush_tlb_page
 300  *
 301  * Description:  This routine flushes one page.
 302  *
 303  * Born on Date: 2002.02.05
 304  *
 305  * Arguments:    *vma - a pointer to the vma struct include va
 306  *               va - virtual address for flush TLB
 307  *
 308  * Returns:      void (cannot fail)
 309  *
 310  * Modification log:
 311  * Date       Who Description
 312  * ---------- --- --------------------------------------------------------
 313  *
 314  *==========================================================================*/
 315 void smp_flush_tlb_page(struct vm_area_struct *vma, unsigned long va)
 316 {
 317         struct mm_struct *mm = vma->vm_mm;
 318         int cpu_id;
 319         cpumask_t cpu_mask;
 320         unsigned long *mmc;
 321         unsigned long flags;
 322
 323         preempt_disable();
 324         cpu_id = smp_processor_id();
 325         mmc = &mm->context[cpu_id];
 326         cpumask_copy(&cpu_mask, mm_cpumask(mm));
 327         cpumask_clear_cpu(cpu_id, &cpu_mask);
 328
 329 #ifdef DEBUG_SMP
 330         if (!mm)
 331                 BUG();
 332 #endif
 333
 334         if (*mmc != NO_CONTEXT) {
 335                 local_irq_save(flags);
 336                 va &= PAGE_MASK;
 337                 va |= (*mmc & MMU_CONTEXT_ASID_MASK);
 338                 __flush_tlb_page(va);
 339                 local_irq_restore(flags);
 340         }
 341         if (!cpumask_empty(&cpu_mask))
 342                 flush_tlb_others(cpu_mask, mm, vma, va);
 343
 344         preempt_enable();
 345 }
 346
 347 /*==========================================================================*
 348  * Name:         flush_tlb_others
 349  *
 350  * Description:  This routine requests other CPU to execute flush TLB.
 351  *               1.Setup parameters.
 352  *               2.Send 'INVALIDATE_TLB_IPI' to other CPU.
 353  *                 Request other CPU to execute 'smp_invalidate_interrupt()'.
 354  *               3.Wait for other CPUs operation finished.
 355  *
 356  * Born on Date: 2002.02.05
 357  *
 358  * Arguments:    cpumask - bitmap of target CPUs
 359  *               *mm -  a pointer to the mm struct for flush TLB
 360  *               *vma -  a pointer to the vma struct include va
 361  *               va - virtual address for flush TLB
 362  *
 363  * Returns:      void (cannot fail)
 364  *
 365  * Modification log:
 366  * Date       Who Description
 367  * ---------- --- --------------------------------------------------------
 368  *
 369  *==========================================================================*/
 370 static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm,
 371         struct vm_area_struct *vma, unsigned long va)
 372 {
 373         unsigned long *mask;
 374 #ifdef DEBUG_SMP
 375         unsigned long flags;
 376         __save_flags(flags);
 377         if (!(flags & 0x0040))  /* Interrupt Disable NONONO */
 378                 BUG();
 379 #endif /* DEBUG_SMP */
 380
 381         /*
 382          * A couple of (to be removed) sanity checks:
 383          *
 384          * - we do not send IPIs to not-yet booted CPUs.
 385          * - current CPU must not be in mask
 386          * - mask must exist :)
 387          */
 388         BUG_ON(cpumask_empty(&cpumask));
 389
 390         BUG_ON(cpumask_test_cpu(smp_processor_id(), &cpumask));
 391         BUG_ON(!mm);
 392
 393         /* If a CPU which we ran on has gone down, OK. */
 394         cpumask_and(&cpumask, &cpumask, cpu_online_mask);
 395         if (cpumask_empty(&cpumask))
 396                 return;
 397
 398         /*
 399          * i'm not happy about this global shared spinlock in the
 400          * MM hot path, but we'll see how contended it is.
 401          * Temporarily this turns IRQs off, so that lockups are
 402          * detected by the NMI watchdog.
 403          */
 404         spin_lock(&tlbstate_lock);
 405
 406         flush_mm = mm;
 407         flush_vma = vma;
 408         flush_va = va;
 409         mask=cpumask_bits(&cpumask);
 410         atomic_set_mask(*mask, (atomic_t *)&flush_cpumask);
 411
 412         /*
 413          * We have to send the IPI only to
 414          * CPUs affected.
 415          */
 416         send_IPI_mask(&cpumask, INVALIDATE_TLB_IPI, 0);
 417
 418         while (!cpumask_empty((cpumask_t*)&flush_cpumask)) {
 419                 /* nothing. lockup detection does not belong here */
 420                 mb();
 421         }
 422
 423         flush_mm = NULL;
 424         flush_vma = NULL;
 425         flush_va = 0;
 426         spin_unlock(&tlbstate_lock);
 427 }
 428
 429 /*==========================================================================*
 430  * Name:         smp_invalidate_interrupt
 431  *
 432  * Description:  This routine executes on CPU which received
 433  *               'INVALIDATE_TLB_IPI'.
 434  *               1.Flush local TLB.
 435  *               2.Report flush TLB process was finished.
 436  *
 437  * Born on Date: 2002.02.05
 438  *
 439  * Arguments:    NONE
 440  *
 441  * Returns:      void (cannot fail)
 442  *
 443  * Modification log:
 444  * Date       Who Description
 445  * ---------- --- --------------------------------------------------------
 446  *
 447  *==========================================================================*/
 448 void smp_invalidate_interrupt(void)
 449 {
 450         int cpu_id = smp_processor_id();
 451         unsigned long *mmc = &flush_mm->context[cpu_id];
 452
 453         if (!cpumask_test_cpu(cpu_id, &flush_cpumask))
 454                 return;
 455
 456         if (flush_va == FLUSH_ALL) {
 457                 *mmc = NO_CONTEXT;
 458                 if (flush_mm == current->active_mm)
 459                         activate_context(flush_mm);
 460                 else
 461                         cpumask_clear_cpu(cpu_id, mm_cpumask(flush_mm));
 462         } else {
 463                 unsigned long va = flush_va;
 464
 465                 if (*mmc != NO_CONTEXT) {
 466                         va &= PAGE_MASK;
 467                         va |= (*mmc & MMU_CONTEXT_ASID_MASK);
 468                         __flush_tlb_page(va);
 469                 }
 470         }
 471         cpumask_clear_cpu(cpu_id, (cpumask_t*)&flush_cpumask);
 472 }
 473
 474 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 475 /* Stop CPU request Routines                                                 */
 476 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 477
 478 /*==========================================================================*
 479  * Name:         smp_send_stop
 480  *
 481  * Description:  This routine requests stop all CPUs.
 482  *               1.Request other CPU to execute 'stop_this_cpu()'.
 483  *
 484  * Born on Date: 2002.02.05
 485  *
 486  * Arguments:    NONE
 487  *
 488  * Returns:      void (cannot fail)
 489  *
 490  * Modification log:
 491  * Date       Who Description
 492  * ---------- --- --------------------------------------------------------
 493  *
 494  *==========================================================================*/
 495 void smp_send_stop(void)
 496 {
 497         smp_call_function(stop_this_cpu, NULL, 0);
 498 }
 499
 500 /*==========================================================================*
 501  * Name:         stop_this_cpu
 502  *
 503  * Description:  This routine halt CPU.
 504  *
 505  * Born on Date: 2002.02.05
 506  *
 507  * Arguments:    NONE
 508  *
 509  * Returns:      void (cannot fail)
 510  *
 511  * Modification log:
 512  * Date       Who Description
 513  * ---------- --- --------------------------------------------------------
 514  *
 515  *==========================================================================*/
 516 static void stop_this_cpu(void *dummy)
 517 {
 518         int cpu_id = smp_processor_id();
 519
 520         /*
 521          * Remove this CPU:
 522          */
 523         set_cpu_online(cpu_id, false);
 524
 525         /*
 526          * PSW IE = 1;
 527          * IMASK = 0;
 528          * goto SLEEP
 529          */
 530         local_irq_disable();
 531         outl(0, M32R_ICU_IMASK_PORTL);
 532         inl(M32R_ICU_IMASK_PORTL);      /* dummy read */
 533         local_irq_enable();
 534
 535         for ( ; ; );
 536 }
 537
 538 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 539 {
 540         send_IPI_mask(mask, CALL_FUNCTION_IPI, 0);
 541 }
 542
 543 void arch_send_call_function_single_ipi(int cpu)
 544 {
 545         send_IPI_mask(cpumask_of(cpu), CALL_FUNC_SINGLE_IPI, 0);
 546 }
 547
 548 /*==========================================================================*
 549  * Name:         smp_call_function_interrupt
 550  *
 551  * Description:  This routine executes on CPU which received
 552  *               'CALL_FUNCTION_IPI'.
 553  *
 554  * Born on Date: 2002.02.05
 555  *
 556  * Arguments:    NONE
 557  *
 558  * Returns:      void (cannot fail)
 559  *
 560  * Modification log:
 561  * Date       Who Description
 562  * ---------- --- --------------------------------------------------------
 563  *
 564  *==========================================================================*/
 565 void smp_call_function_interrupt(void)
 566 {
 567         irq_enter();
 568         generic_smp_call_function_interrupt();
 569         irq_exit();
 570 }
 571
 572 void smp_call_function_single_interrupt(void)
 573 {
 574         irq_enter();
 575         generic_smp_call_function_single_interrupt();
 576         irq_exit();
 577 }
 578
 579 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 580 /* Timer Routines                                                            */
 581 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 582
 583 /*==========================================================================*
 584  * Name:         smp_send_timer
 585  *
 586  * Description:  This routine sends a 'LOCAL_TIMER_IPI' to all other CPUs
 587  *               in the system.
 588  *
 589  * Born on Date: 2002.02.05
 590  *
 591  * Arguments:    NONE
 592  *
 593  * Returns:      void (cannot fail)
 594  *
 595  * Modification log:
 596  * Date       Who Description
 597  * ---------- --- --------------------------------------------------------
 598  *
 599  *==========================================================================*/
 600 void smp_send_timer(void)
 601 {
 602         send_IPI_allbutself(LOCAL_TIMER_IPI, 1);
 603 }
 604
 605 /*==========================================================================*
 606  * Name:         smp_send_timer
 607  *
 608  * Description:  This routine executes on CPU which received
 609  *               'LOCAL_TIMER_IPI'.
 610  *
 611  * Born on Date: 2002.02.05
 612  *
 613  * Arguments:    *regs - a pointer to the saved regster info
 614  *
 615  * Returns:      void (cannot fail)
 616  *
 617  * Modification log:
 618  * Date       Who Description
 619  * ---------- --- --------------------------------------------------------
 620  *
 621  *==========================================================================*/
 622 void smp_ipi_timer_interrupt(struct pt_regs *regs)
 623 {
 624         struct pt_regs *old_regs;
 625         old_regs = set_irq_regs(regs);
 626         irq_enter();
 627         smp_local_timer_interrupt();
 628         irq_exit();
 629         set_irq_regs(old_regs);
 630 }
 631
 632 /*==========================================================================*
 633  * Name:         smp_local_timer_interrupt
 634  *
 635  * Description:  Local timer interrupt handler. It does both profiling and
 636  *               process statistics/rescheduling.
 637  *               We do profiling in every local tick, statistics/rescheduling
 638  *               happen only every 'profiling multiplier' ticks. The default
 639  *               multiplier is 1 and it can be changed by writing the new
 640  *               multiplier value into /proc/profile.
 641  *
 642  * Born on Date: 2002.02.05
 643  *
 644  * Arguments:    *regs - a pointer to the saved regster info
 645  *
 646  * Returns:      void (cannot fail)
 647  *
 648  * Original:     arch/i386/kernel/apic.c
 649  *
 650  * Modification log:
 651  * Date       Who Description
 652  * ---------- --- --------------------------------------------------------
 653  * 2003-06-24 hy  use per_cpu structure.
 654  *==========================================================================*/
 655 void smp_local_timer_interrupt(void)
 656 {
 657         int user = user_mode(get_irq_regs());
 658         int cpu_id = smp_processor_id();
 659
 660         /*
 661          * The profiling function is SMP safe. (nothing can mess
 662          * around with "current", and the profiling counters are
 663          * updated with atomic operations). This is especially
 664          * useful with a profiling multiplier != 1
 665          */
 666
 667         profile_tick(CPU_PROFILING);
 668
 669         if (--per_cpu(prof_counter, cpu_id) <= 0) {
 670                 /*
 671                  * The multiplier may have changed since the last time we got
 672                  * to this point as a result of the user writing to
 673                  * /proc/profile. In this case we need to adjust the APIC
 674                  * timer accordingly.
 675                  *
 676                  * Interrupts are already masked off at this point.
 677                  */
 678                 per_cpu(prof_counter, cpu_id)
 679                         = per_cpu(prof_multiplier, cpu_id);
 680                 if (per_cpu(prof_counter, cpu_id)
 681                         != per_cpu(prof_old_multiplier, cpu_id))
 682                 {
 683                         per_cpu(prof_old_multiplier, cpu_id)
 684                                 = per_cpu(prof_counter, cpu_id);
 685                 }
 686
 687                 update_process_times(user);
 688         }
 689 }
 690
 691 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 692 /* Send IPI Routines                                                         */
 693 /*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*/
 694
 695 /*==========================================================================*
 696  * Name:         send_IPI_allbutself
 697  *
 698  * Description:  This routine sends a IPI to all other CPUs in the system.
 699  *
 700  * Born on Date: 2002.02.05
 701  *
 702  * Arguments:    ipi_num - Number of IPI
 703  *               try -  0 : Send IPI certainly.
 704  *                     !0 : The following IPI is not sent when Target CPU
 705  *                          has not received the before IPI.
 706  *
 707  * Returns:      void (cannot fail)
 708  *
 709  * Modification log:
 710  * Date       Who Description
 711  * ---------- --- --------------------------------------------------------
 712  *
 713  *==========================================================================*/
 714 static void send_IPI_allbutself(int ipi_num, int try)
 715 {
 716         cpumask_t cpumask;
 717
 718         cpumask_copy(&cpumask, cpu_online_mask);
 719         cpumask_clear_cpu(smp_processor_id(), &cpumask);
 720
 721         send_IPI_mask(&cpumask, ipi_num, try);
 722 }
 723
 724 /*==========================================================================*
 725  * Name:         send_IPI_mask
 726  *
 727  * Description:  This routine sends a IPI to CPUs in the system.
 728  *
 729  * Born on Date: 2002.02.05
 730  *
 731  * Arguments:    cpu_mask - Bitmap of target CPUs logical ID
 732  *               ipi_num - Number of IPI
 733  *               try -  0 : Send IPI certainly.
 734  *                     !0 : The following IPI is not sent when Target CPU
 735  *                          has not received the before IPI.
 736  *
 737  * Returns:      void (cannot fail)
 738  *
 739  * Modification log:
 740  * Date       Who Description
 741  * ---------- --- --------------------------------------------------------
 742  *
 743  *==========================================================================*/
 744 static void send_IPI_mask(const struct cpumask *cpumask, int ipi_num, int try)
 745 {
 746         cpumask_t physid_mask, tmp;
 747         int cpu_id, phys_id;
 748         int num_cpus = num_online_cpus();
 749
 750         if (num_cpus <= 1)      /* NO MP */
 751                 return;
 752
 753         cpumask_and(&tmp, cpumask, cpu_online_mask);
 754         BUG_ON(!cpumask_equal(cpumask, &tmp));
 755
 756         cpumask_clear(&physid_mask);
 757         for_each_cpu(cpu_id, cpumask) {
 758                 if ((phys_id = cpu_to_physid(cpu_id)) != -1)
 759                         cpumask_set_cpu(phys_id, &physid_mask);
 760         }
 761
 762         send_IPI_mask_phys(&physid_mask, ipi_num, try);
 763 }
 764
 765 /*==========================================================================*
 766  * Name:         send_IPI_mask_phys
 767  *
 768  * Description:  This routine sends a IPI to other CPUs in the system.
 769  *
 770  * Born on Date: 2002.02.05
 771  *
 772  * Arguments:    cpu_mask - Bitmap of target CPUs physical ID
 773  *               ipi_num - Number of IPI
 774  *               try -  0 : Send IPI certainly.
 775  *                     !0 : The following IPI is not sent when Target CPU
 776  *                          has not received the before IPI.
 777  *
 778  * Returns:      IPICRi regster value.
 779  *
 780  * Modification log:
 781  * Date       Who Description
 782  * ---------- --- --------------------------------------------------------
 783  *
 784  *==========================================================================*/
 785 unsigned long send_IPI_mask_phys(const cpumask_t *physid_mask, int ipi_num,
 786         int try)
 787 {
 788         spinlock_t *ipilock;
 789         volatile unsigned long *ipicr_addr;
 790         unsigned long ipicr_val;
 791         unsigned long my_physid_mask;
 792         unsigned long mask = cpumask_bits(physid_mask)[0];
 793
 794
 795         if (mask & ~physids_coerce(phys_cpu_present_map))
 796                 BUG();
 797         if (ipi_num >= NR_IPIS || ipi_num < 0)
 798                 BUG();
 799
 800         mask <<= IPI_SHIFT;
 801         ipilock = &ipi_lock[ipi_num];
 802         ipicr_addr = (volatile unsigned long *)(M32R_ICU_IPICR_ADDR
 803                 + (ipi_num << 2));
 804         my_physid_mask = ~(1 << smp_processor_id());
 805
 806         /*
 807          * lock ipi_lock[i]
 808          * check IPICRi == 0
 809          * write IPICRi (send IPIi)
 810          * unlock ipi_lock[i]
 811          */
 812         spin_lock(ipilock);
 813         __asm__ __volatile__ (
 814                 ";; CHECK IPICRi == 0           \n\t"
 815                 ".fillinsn                      \n"
 816                 "1:                             \n\t"
 817                 "ld     %0, @%1                 \n\t"
 818                 "and    %0, %4                  \n\t"
 819                 "beqz   %0, 2f                  \n\t"
 820                 "bnez   %3, 3f                  \n\t"
 821                 "bra    1b                      \n\t"
 822                 ";; WRITE IPICRi (send IPIi)    \n\t"
 823                 ".fillinsn                      \n"
 824                 "2:                             \n\t"
 825                 "st     %2, @%1                 \n\t"
 826                 ".fillinsn                      \n"
 827                 "3:                             \n\t"
 828                 : "=&r"(ipicr_val)
 829                 : "r"(ipicr_addr), "r"(mask), "r"(try), "r"(my_physid_mask)
 830                 : "memory"
 831         );
 832         spin_unlock(ipilock);
 833
 834         return ipicr_val;
 835 }