Avoid TLB flush IPIs for the cores in deeper c-states by voluntary leave_mm()
before entering into that state. CPUs tend to flush TLB in those c-states
anyways.
acpi_idle does this with C3-type states, but it was not caried over
when intel_idle was introduced. intel_idle can apply it
to C-states in addition to those that ACPI might export as C3...
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
intel_idle_cpuidle_devices is a percpu pointer
but was missing __percpu markup.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
intel_idle: recognize Lincroft Atom Processor
intel_idle: no longer EXPERIMENTAL
intel_idle: disable module support
intel_idle: add support for Westmere-EX
intel_idle: delete power_policy modparam, and choose substate functions
intel_idle: delete substates DEBUG modparam
The idea behind power policy was that it would start off as a modparam,
and then hook into the new "global" in-kernel power vs energy tunable.
But that tunable isn't happening, so delete the hook here.
With the policy hook gone, the sub-state choice functions
do not do anything useful, so delete them from the critical path.
To handle sub-states in the future, we will advertise them
with dedicated cpuidle_state entries. That is necessary
because some of the sub-states will have substantially different
properties than their peer sub-states.
Signed-off-by: Len Brown <len.brown@intel.com>
This EXPERIMENTAL driver supersedes acpi_idle on
Intel Atom Processors, Intel Core i3/i5/i7 Processors
and associated Intel Xeon processors.
It does not support the Intel Core2 processor or earlier.
For kernels configured with ACPI, CONFIG_INTEL_IDLE=y
allows intel_idle to probe before the ACPI processor driver.
Booting with "intel_idle.max_cstate=0" disables intel_idle
and the system will fall back on ACPI's "acpi_idle".
Typical Linux distributions load ACPI processor module early,
making CONFIG_INTEL_IDLE=m not easily useful on ACPI platforms.
intel_idle probes all processors at module_init time.
Processors that are hot-added later will be limited
to using C1 in idle.
Signed-off-by: Len Brown <len.brown@intel.com>