Intel Rewrites TurboStat Plus IVB CPU Idle Support

Another one of the pulls going into the Linux 3.6 kernel this week is the ACPI and power management updates courtesy of Intel. The two prominent changes for this next Linux kernel release is a rewrite of the "turbostat" tool and the "intel_idle" CPU idle driver now supports Ivy Bridge processors.

Len Brown of Intel had his ACPI and power management update pulled by Linus on Thursday. There's some generic cpuidle driver work, thermal management changes for non-ACPI systems, and an ACPICA core update, but the two key changes for Linux 3.6 are:

- Intel's "turbostat" tool has been re-written. Turbostat is the Intel utility living within the kernel tree for reporting processor frequency and idle statistics for recent Intel Core and Atom processors, namely those supporting Intel Turbo Boost Technology. The turbostat rewrite is primarily for lowering the overhead in order to measure very large systems when they are completely idle.

- The "intel_idle" driver now supports Ivy Bridge processors. This is the CPU idle driver that is optimized for Intel hardware with more specific hardware idle features compared to the generic acpi_idle driver. This may lead to Intel Ivy Bridge power savings when upgrading to the Linux 3.6 kernel.