x86, perf_counter, bts: Add BTS support to perfcounters
Implement a performance counter with:
attr.type = PERF_TYPE_HARDWARE
attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS
attr.sample_period = 1
Using branch trace store (BTS) on x86 hardware, if available.
The from and to address for each branch can be sampled using:
PERF_SAMPLE_IP for the from address
PERF_SAMPLE_ADDR for the to address
[ v2: address review feedback, fix bugs ]
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
4 files changed