tree fbae0f68f62f02803e17309a3d1180619d4fdd31
parent 60cfff3516580f5c782cef4dc28f2974c4df8ed1
author Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> 1124999940 -0400
committer Len Brown <len.brown@intel.com> 1125109353 -0400

[ACPI] Reduce acpi-cpufreq switching latency by 50%

The acpi-cpufreq driver does a P-state get after a P-state set
to verify whether set went through successfully. This test
is kind of redundant as set goes throught most of the times,
and the test is also expensive as a get of P-states can
take a lot of time (same as a set operation) as it goes
through SMM mode. Effectively, we are doubling the P-state
latency due to this get opertion.

momdule parameter "acpi_pstate_strict" restores orginal paranoia.

http://bugzilla.kernel.org/show_bug.cgi?id=5129

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>