Eric Lee / smarc-fsl-linux-kernel

06 Nov, 2015

1 commit

  • ac1f59124   kernel/watchdog.c: add sysctl knob hardlockup_panic ... Browse Code »

    The only way to enable a hardlockup to panic the machine is to set
    'nmi_watchdog=panic' on the kernel command line.

    This makes it awkward for end users and folks who want to run automate
    tests (like myself).

    Mimic the softlockup_panic knob and create a /proc/sys/kernel/hardlockup_panic
    knob.

    Signed-off-by: Don Zickus
    Cc: Ulrich Obergfell
    Acked-by: Jiri Kosina
    Reviewed-by: Aaron Tomlin
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Don Zickus
     

25 Jun, 2015

1 commit

  • fe4ba3c34   watchdog: add watchdog_cpumask sysctl to assist nohz ... Browse Code »

    Change the default behavior of watchdog so it only runs on the
    housekeeping cores when nohz_full is enabled at build and boot time.
    Allow modifying the set of cores the watchdog is currently running on
    with a new kernel.watchdog_cpumask sysctl.

    In the current system, the watchdog subsystem runs a periodic timer that
    schedules the watchdog kthread to run. However, nohz_full cores are
    designed to allow userspace application code running on those cores to
    have 100% access to the CPU. So the watchdog system prevents the
    nohz_full application code from being able to run the way it wants to,
    thus the motivation to suppress the watchdog on nohz_full cores, which
    this patchset provides by default.

    However, if we disable the watchdog globally, then the housekeeping
    cores can't benefit from the watchdog functionality. So we allow
    disabling it only on some cores. See Documentation/lockup-watchdogs.txt
    for more information.

    [jhubbard@nvidia.com: fix a watchdog crash in some configurations]
    Signed-off-by: Chris Metcalf
    Acked-by: Don Zickus
    Cc: Ingo Molnar
    Cc: Ulrich Obergfell
    Cc: Thomas Gleixner
    Cc: Peter Zijlstra
    Cc: Frederic Weisbecker
    Signed-off-by: John Hubbard
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Chris Metcalf
     

26 Aug, 2014

1 commit

11 Feb, 2012

1 commit

  • 9919cba7f   watchdog: Update documentation ... Browse Code »

    The soft and hard lockup detectors are now built on top of the
    hrtimer and perf subsystems. Update the documentation
    accordingly.

    Signed-off-by: Fernando Luis Vazquez Cao
    Acked-by: Randy Dunlap
    Signed-off-by: Don Zickus
    Link: http://lkml.kernel.org/r/1328827342-6253-1-git-send-email-dzickus@redhat.com
    Signed-off-by: Ingo Molnar

    Fernando Luis Vázquez Cao