[PATCH 35/37] perf intel-pt: Do not use TSC packets for calculating CPU cycles to TSC

2017-05-19 Thread Adrian Hunter
CBR (core-to-bus ratio) packets provide an indication of CPU frequency. A more accurate measure can be made by counting the cycles (given by CYC packets) in between other timing packets (either MTC or TSC). Using TSC packets has at least 2 issues: 1) timing might have stopped (e.g. mwait) or 2)

[PATCH 35/37] perf intel-pt: Do not use TSC packets for calculating CPU cycles to TSC

2017-05-19 Thread Adrian Hunter
CBR (core-to-bus ratio) packets provide an indication of CPU frequency. A more accurate measure can be made by counting the cycles (given by CYC packets) in between other timing packets (either MTC or TSC). Using TSC packets has at least 2 issues: 1) timing might have stopped (e.g. mwait) or 2)