[perfmon2] Intel Nehalem support

[stephane e. <er...@go...>]

Hello,

I have now uploaded the libpfm code to support the Intel Nehalem processors.

The libpfm code supports:
    - core PMU, generic and fixed counters
    - core PMU offcore_response_0 support
    - uncore PMU, generic and fixed counters
    - PEBS, including load latency filtering
    - LBR, including LBR filtering
    - libpfm_nehalem man page (read first)

Hopefully, later this week, I will release the kernel and pfmon support.

Note that you can test the libpfm Nehalem support without dedicated kernel
support. The kernel will default to architectural perfmon support and it will
provide you with the 4 generic + 3 fixed counters of the core PMU.

Note that due to important kernel changes related to DS_AREA in 2.6.28,
the PEBS support for Nehalem, Core, and Atom must be revisited, thus it will
take some time. Note that the changes may not be backward compatible on
Core and Atom. Nehalem introduces a new PEBS format, so we will fine there.

Thanks to Intel for providing the event table information.

Enjoy,