diff options
-rw-r--r-- | arch/i386/kernel/smp.c | 68 | ||||
-rw-r--r-- | arch/x86_64/kernel/smp.c | 28 | ||||
-rw-r--r-- | include/asm-x86_64/smp.h | 1 |
3 files changed, 48 insertions, 49 deletions
diff --git a/arch/i386/kernel/smp.c b/arch/i386/kernel/smp.c index 0e8977871b1f..0cd459baad68 100644 --- a/arch/i386/kernel/smp.c +++ b/arch/i386/kernel/smp.c | |||
@@ -515,35 +515,14 @@ void unlock_ipi_call_lock(void) | |||
515 | 515 | ||
516 | static struct call_data_struct *call_data; | 516 | static struct call_data_struct *call_data; |
517 | 517 | ||
518 | /** | 518 | static void __smp_call_function(void (*func) (void *info), void *info, |
519 | * smp_call_function(): Run a function on all other CPUs. | 519 | int nonatomic, int wait) |
520 | * @func: The function to run. This must be fast and non-blocking. | ||
521 | * @info: An arbitrary pointer to pass to the function. | ||
522 | * @nonatomic: currently unused. | ||
523 | * @wait: If true, wait (atomically) until function has completed on other CPUs. | ||
524 | * | ||
525 | * Returns 0 on success, else a negative status code. Does not return until | ||
526 | * remote CPUs are nearly ready to execute <<func>> or are or have executed. | ||
527 | * | ||
528 | * You must not call this function with disabled interrupts or from a | ||
529 | * hardware interrupt handler or from a bottom half handler. | ||
530 | */ | ||
531 | int smp_call_function (void (*func) (void *info), void *info, int nonatomic, | ||
532 | int wait) | ||
533 | { | 520 | { |
534 | struct call_data_struct data; | 521 | struct call_data_struct data; |
535 | int cpus; | 522 | int cpus = num_online_cpus() - 1; |
536 | |||
537 | /* Holding any lock stops cpus from going down. */ | ||
538 | spin_lock(&call_lock); | ||
539 | cpus = num_online_cpus() - 1; | ||
540 | if (!cpus) { | ||
541 | spin_unlock(&call_lock); | ||
542 | return 0; | ||
543 | } | ||
544 | 523 | ||
545 | /* Can deadlock when called with interrupts disabled */ | 524 | if (!cpus) |
546 | WARN_ON(irqs_disabled()); | 525 | return; |
547 | 526 | ||
548 | data.func = func; | 527 | data.func = func; |
549 | data.info = info; | 528 | data.info = info; |
@@ -565,6 +544,30 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic, | |||
565 | if (wait) | 544 | if (wait) |
566 | while (atomic_read(&data.finished) != cpus) | 545 | while (atomic_read(&data.finished) != cpus) |
567 | cpu_relax(); | 546 | cpu_relax(); |
547 | } | ||
548 | |||
549 | /** | ||
550 | * smp_call_function(): Run a function on all other CPUs. | ||
551 | * @func: The function to run. This must be fast and non-blocking. | ||
552 | * @info: An arbitrary pointer to pass to the function. | ||
553 | * @nonatomic: currently unused. | ||
554 | * @wait: If true, wait (atomically) until function has completed on other CPUs. | ||
555 | * | ||
556 | * Returns 0 on success, else a negative status code. Does not return until | ||
557 | * remote CPUs are nearly ready to execute <<func>> or are or have executed. | ||
558 | * | ||
559 | * You must not call this function with disabled interrupts or from a | ||
560 | * hardware interrupt handler or from a bottom half handler. | ||
561 | */ | ||
562 | int smp_call_function (void (*func) (void *info), void *info, int nonatomic, | ||
563 | int wait) | ||
564 | { | ||
565 | /* Can deadlock when called with interrupts disabled */ | ||
566 | WARN_ON(irqs_disabled()); | ||
567 | |||
568 | /* Holding any lock stops cpus from going down. */ | ||
569 | spin_lock(&call_lock); | ||
570 | __smp_call_function(func, info, nonatomic, wait); | ||
568 | spin_unlock(&call_lock); | 571 | spin_unlock(&call_lock); |
569 | 572 | ||
570 | return 0; | 573 | return 0; |
@@ -573,11 +576,11 @@ EXPORT_SYMBOL(smp_call_function); | |||
573 | 576 | ||
574 | static void stop_this_cpu (void * dummy) | 577 | static void stop_this_cpu (void * dummy) |
575 | { | 578 | { |
579 | local_irq_disable(); | ||
576 | /* | 580 | /* |
577 | * Remove this CPU: | 581 | * Remove this CPU: |
578 | */ | 582 | */ |
579 | cpu_clear(smp_processor_id(), cpu_online_map); | 583 | cpu_clear(smp_processor_id(), cpu_online_map); |
580 | local_irq_disable(); | ||
581 | disable_local_APIC(); | 584 | disable_local_APIC(); |
582 | if (cpu_data[smp_processor_id()].hlt_works_ok) | 585 | if (cpu_data[smp_processor_id()].hlt_works_ok) |
583 | for(;;) halt(); | 586 | for(;;) halt(); |
@@ -590,11 +593,16 @@ static void stop_this_cpu (void * dummy) | |||
590 | 593 | ||
591 | void smp_send_stop(void) | 594 | void smp_send_stop(void) |
592 | { | 595 | { |
593 | smp_call_function(stop_this_cpu, NULL, 1, 0); | 596 | /* Don't deadlock on the call lock in panic */ |
597 | int nolock = !spin_trylock(&call_lock); | ||
598 | unsigned long flags; | ||
594 | 599 | ||
595 | local_irq_disable(); | 600 | local_irq_save(flags); |
601 | __smp_call_function(stop_this_cpu, NULL, 0, 0); | ||
602 | if (!nolock) | ||
603 | spin_unlock(&call_lock); | ||
596 | disable_local_APIC(); | 604 | disable_local_APIC(); |
597 | local_irq_enable(); | 605 | local_irq_restore(flags); |
598 | } | 606 | } |
599 | 607 | ||
600 | /* | 608 | /* |
diff --git a/arch/x86_64/kernel/smp.c b/arch/x86_64/kernel/smp.c index af1ec4d23cf8..bd1d123947ce 100644 --- a/arch/x86_64/kernel/smp.c +++ b/arch/x86_64/kernel/smp.c | |||
@@ -452,42 +452,34 @@ int smp_call_function (void (*func) (void *info), void *info, int nonatomic, | |||
452 | } | 452 | } |
453 | EXPORT_SYMBOL(smp_call_function); | 453 | EXPORT_SYMBOL(smp_call_function); |
454 | 454 | ||
455 | void smp_stop_cpu(void) | 455 | static void stop_this_cpu(void *dummy) |
456 | { | 456 | { |
457 | unsigned long flags; | 457 | local_irq_disable(); |
458 | /* | 458 | /* |
459 | * Remove this CPU: | 459 | * Remove this CPU: |
460 | */ | 460 | */ |
461 | cpu_clear(smp_processor_id(), cpu_online_map); | 461 | cpu_clear(smp_processor_id(), cpu_online_map); |
462 | local_irq_save(flags); | ||
463 | disable_local_APIC(); | 462 | disable_local_APIC(); |
464 | local_irq_restore(flags); | ||
465 | } | ||
466 | |||
467 | static void smp_really_stop_cpu(void *dummy) | ||
468 | { | ||
469 | smp_stop_cpu(); | ||
470 | for (;;) | 463 | for (;;) |
471 | halt(); | 464 | halt(); |
472 | } | 465 | } |
473 | 466 | ||
474 | void smp_send_stop(void) | 467 | void smp_send_stop(void) |
475 | { | 468 | { |
476 | int nolock = 0; | 469 | int nolock; |
470 | unsigned long flags; | ||
471 | |||
477 | if (reboot_force) | 472 | if (reboot_force) |
478 | return; | 473 | return; |
474 | |||
479 | /* Don't deadlock on the call lock in panic */ | 475 | /* Don't deadlock on the call lock in panic */ |
480 | if (!spin_trylock(&call_lock)) { | 476 | nolock = !spin_trylock(&call_lock); |
481 | /* ignore locking because we have panicked anyways */ | 477 | local_irq_save(flags); |
482 | nolock = 1; | 478 | __smp_call_function(stop_this_cpu, NULL, 0, 0); |
483 | } | ||
484 | __smp_call_function(smp_really_stop_cpu, NULL, 0, 0); | ||
485 | if (!nolock) | 479 | if (!nolock) |
486 | spin_unlock(&call_lock); | 480 | spin_unlock(&call_lock); |
487 | |||
488 | local_irq_disable(); | ||
489 | disable_local_APIC(); | 481 | disable_local_APIC(); |
490 | local_irq_enable(); | 482 | local_irq_restore(flags); |
491 | } | 483 | } |
492 | 484 | ||
493 | /* | 485 | /* |
diff --git a/include/asm-x86_64/smp.h b/include/asm-x86_64/smp.h index f4236d7789aa..d5704421456b 100644 --- a/include/asm-x86_64/smp.h +++ b/include/asm-x86_64/smp.h | |||
@@ -37,7 +37,6 @@ extern void lock_ipi_call_lock(void); | |||
37 | extern void unlock_ipi_call_lock(void); | 37 | extern void unlock_ipi_call_lock(void); |
38 | extern int smp_num_siblings; | 38 | extern int smp_num_siblings; |
39 | extern void smp_send_reschedule(int cpu); | 39 | extern void smp_send_reschedule(int cpu); |
40 | void smp_stop_cpu(void); | ||
41 | 40 | ||
42 | extern cpumask_t cpu_sibling_map[NR_CPUS]; | 41 | extern cpumask_t cpu_sibling_map[NR_CPUS]; |
43 | extern cpumask_t cpu_core_map[NR_CPUS]; | 42 | extern cpumask_t cpu_core_map[NR_CPUS]; |