From: Thomas Gleixner Date: Wed, 11 Apr 2012 21:49:16 +0000 (+0200) Subject: Revert "clocksource: Load the ACPI PM clocksource asynchronously" X-Git-Tag: v3.4-rc3~29^2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d48fc63f6f3f485ed5aa9cf019d8e8e3a7d10263;p=pandora-kernel.git Revert "clocksource: Load the ACPI PM clocksource asynchronously" This reverts commit b519508298e0292e1771eecf14aaf67755adc39d. The reason for this revert is that making the frequency verification preemptible and interruptible is not working reliably. Michaels machine failed to use PM-timer with the message: PM-Timer running at invalid rate: 113% of normal - aborting. That's not a surprise as the frequency verification does rely on interrupts being disabled. With a async scheduled thread there is no guarantee to achieve the same result. Also some driver might fiddle with the CTC channel 2 during the verification period, which makes the result even more random and unpredictable. This can be solved by using the same mechanism as we use in the deferred TSC validation code, but that only will work if we verified a working HPET _BEFORE_ trying to do the PM-Timer lazy validation. So for now reverting is the safe option. Bisected-by: Michael Witten Cc: Arjan van de Ven Cc: Arjan van de Ven Cc: John Stultz Cc: Len Brown LKML-Reference: Signed-off-by: Thomas Gleixner --- Reading git-diff-tree failed