On Fri, 20 Jun 2008 03:44:11 -0400 Len Brown wrote: > From: Zhao Yakui <yakui.zhao@xxxxxxxxx> > > Add the boot option of "idle=nomwait" to disable Mwait for CPU C-states. > If the boot option of "idle=nomwait" is added , Linux should not > use mwait for cpu idle even when the mwait is supported. In such case the > C2C3_FFH access mode will be disabled. > > http://bugzilla.kernel.org/show_bug.cgi?id=10807 > > Signed-off-by: Zhao Yakui <yakui.zhao@xxxxxxxxx> > Signed-off-by: Li Shaohua <shaohua.li@xxxxxxxxx> > Signed-off-by: Len Brown <len.brown@xxxxxxxxx> > --- > Documentation/kernel-parameters.txt | 4 +++- > arch/ia64/kernel/process.c | 2 ++ > arch/x86/kernel/process.c | 14 ++++++++++++++ > drivers/acpi/processor_core.c | 12 ++++++++++++ > include/asm-ia64/processor.h | 1 + > include/asm-x86/processor.h | 1 + > 6 files changed, 33 insertions(+), 1 deletions(-) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 1623c2f..39baaba 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -785,7 +785,7 @@ and is between 256 and 4096 characters. It is defined in the file > See Documentation/ide/ide.txt. > > idle= [X86] > - Format: idle=poll or idle=mwait, idle = halt > + Format: idle=poll or idle=mwait, idle = halt, idle=nomwait idle=halt [no spaces] > Poll forces a polling idle loop that can slightly improves the performance > of waking up a idle CPU, but will use a lot of power and make the system > run hot. Not recommended. > @@ -795,6 +795,8 @@ and is between 256 and 4096 characters. It is defined in the file > as idle=poll. > idle = halt . Halt is forced to be used for CPU idle. idle=halt . (no spaces allowed in command line parsing AFAIK) > In such case C2/C3 won't be used again. > + idle = nomwait. disable Mwait for CPU C-state. > + In such case C2C3_FFH access mode will be disabled. > > ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem > Claim all unknown PCI IDE storage controllers. --- ~Randy Linux Plumbers Conference, 17-19 September 2008, Portland, Oregon USA http://linuxplumbersconf.org/ -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
