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    SubjectRe: [PATCH 2/6] [watchdog] convert touch_softlockup_watchdog to touch_watchdog
    On Tue, Apr 20, 2010 at 11:23:59AM -0400, Don Zickus wrote:
    > Just a scripted conversion to remove touch_softlockup_watchdog.
    >
    > Also converts the once case of touch_all_softlockup_watchdogs to
    > touch_all_watchdogs.
    >
    > This is done as part of the removal of the old softlockup code and
    > transition to the new softlockup code.
    >
    > Signed-off-by: Don Zickus <dzickus@redhat.com>


    In fact I worry a bit about this unification of watchdog touching.
    When we touch the softlockup watchdog, do we also want to touch
    the nmi watchdog?

    Most of the time, I think we don't want to. We usually touch the
    softlockup detector because we know we are abnormally delaying
    the softlockup kthread from being scheduled, and if we are in such
    situation, it means we are doing something in a sensitive context:
    typically the kind of context favorable to create hardlockups...

    But the opposite is right: if we touch the nmi watchdog: it means we
    are abnormally delaying irqs, which means we also are abnormally
    delaying the softlockup kthread from being scheduled, so if we
    touch the nmi watchdog, we also want to touch the softlockup
    detector.

    Hence I guess we want to keep the current state:

    - touch_nmi_watchdog() = touch softlockup and nmi watchdogs
    - touch_softlockup_watchdog() = only touch softlockup watchdog



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