Red Hat Bugzilla – Bug 175988
hang-check timer needs to be build on S390/S390x
Last modified: 2007-11-30 17:07:22 EST
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Description of problem:
hangcheck-timer kernel modules are currently not build on s390 and s390x
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1.install RHEL4 U3 kernel on s390 machine
3.search for hangcheck-timer.ko
This is just a matter of including the Kconfig where HANGCHECK_TIMER
is configured. But this is drivers/char/Kconfig which we currently do not
include from s390 Kconfig since there is too much stuff there that don't makes
sense on s390.
I wonder why the hangcheck timer is not in the watchdog directory?
(The watchdog/Kconfig is included from s390 Kconfig).
The hangcheck timer also needs a monotonic_clock function.
This is currently not implemented on s390 but it could be easily
done by using get_clock().
Um, just figured out that Jason already added the monotonic_clock function,
so this patch is not upstream.
The comment from the archs that have the monotonic_clock() says:
/* monotonic_clock(): returns # of nanoseconds passed since time_init()
Your code just returns get_clock() which is nanoseconds since 1900.
But time_init should refer to the time the machine booted.
Therfore it should be get_clock() - jiffies_timer_cc, or?
well, i agree it doesn't meet the spec, but the way its implemented should be
fine since we subtract out the previous value that monotonic_clock() returned.
thus, the starting point is irrelevant as long as its conssitent.
Correct, it should work if it only takes the difference.
But I think this could be easier done by adding the monotonic_clock
interface to s390 arch code. See my attached patch.
BTW, your definition of the s390 second had a typo ;-
Created attachment 123076 [details]
look good to me...probably worth sending upstream as well.
I've talked with Martin Schwidefsky, he has no objections
to the monotonic_clock in our arch code, so we will send this
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
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