tree 2df816ff6559a0e2f9d7537e1accdfe932e027d4
parent 5f819949ee4e5a06c2e0054cbb42f3f0d170d779
author Clemens Ladisch <clemens@ladisch.de> 1130713416 -0800
committer Linus Torvalds <torvalds@g5.osdl.org> 1130722650 -0800

[PATCH] hpet-RTC: cache the comparator register

Reads from an HPET register require a round trip to the south bridge and are
almost as slow as PCI reads.  By caching the last value we've written to the
comparator register, we can eliminate all HPET reads from the fast path in the
emulated RTC interrupt handler.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>