perf/x86: Implement 64-bit counter support for IBS

perf/x86: Implement 64-bit counter support for IBS

This patch implements 64 bit counter support for IBS. The
sampling period is no longer limited to the hw counter width.

The functions perf_event_set_period() and
perf_event_try_update() can be used as generic functions. They
can replace similar code that is duplicate across architectures.

Signed-off-by: Robert Richter <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>