hw_nmi.c 1.3 KB

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  1. // SPDX-License-Identifier: GPL-2.0
  2. /*
  3. * HW NMI watchdog support
  4. *
  5. * started by Don Zickus, Copyright (C) 2010 Red Hat, Inc.
  6. *
  7. * Arch specific calls to support NMI watchdog
  8. *
  9. * Bits copied from original nmi.c file
  10. *
  11. */
  12. #include <asm/apic.h>
  13. #include <asm/nmi.h>
  14. #include <linux/cpumask.h>
  15. #include <linux/kdebug.h>
  16. #include <linux/notifier.h>
  17. #include <linux/kprobes.h>
  18. #include <linux/nmi.h>
  19. #include <linux/init.h>
  20. #include <linux/delay.h>
  21. #ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
  22. u64 hw_nmi_get_sample_period(int watchdog_thresh)
  23. {
  24. return (u64)(cpu_khz) * 1000 * watchdog_thresh;
  25. }
  26. #endif
  27. #ifdef arch_trigger_cpumask_backtrace
  28. static void nmi_raise_cpu_backtrace(cpumask_t *mask)
  29. {
  30. apic->send_IPI_mask(mask, NMI_VECTOR);
  31. }
  32. void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
  33. {
  34. nmi_trigger_cpumask_backtrace(mask, exclude_self,
  35. nmi_raise_cpu_backtrace);
  36. }
  37. static int nmi_cpu_backtrace_handler(unsigned int cmd, struct pt_regs *regs)
  38. {
  39. if (nmi_cpu_backtrace(regs))
  40. return NMI_HANDLED;
  41. return NMI_DONE;
  42. }
  43. NOKPROBE_SYMBOL(nmi_cpu_backtrace_handler);
  44. static int __init register_nmi_cpu_backtrace_handler(void)
  45. {
  46. register_nmi_handler(NMI_LOCAL, nmi_cpu_backtrace_handler,
  47. 0, "arch_bt");
  48. return 0;
  49. }
  50. early_initcall(register_nmi_cpu_backtrace_handler);
  51. #endif