The formula for calculating guest TSC clock, used in the kernel is: guest_tsc = tsc-offset + (host_tsc * tsc-scaling-ratio) >> tsc-scaling-ratio-frac-bits Current trace-cmd implementation does not take into account fraction bits, when calculating guest clock offset in case of a clock scaling. Additional logic is added, to use the same formula in trace-cmd. The changes are backward compatible with trace-cmd 2.9. The changes are not tested with a kernel that has guest clock scaling enabled. The goal of the patch set is to extend the time sync option, saved in the guest trace.dat file, with all needed data used in the kernel for guest TSC calculations. Tzvetomir Stoyanov (VMware) (3): trace-cmd: Extend host-guest time sync with fraction bits trace-cmd: Read and use fraction bits from TRACECMD_OPTION_TIME_SHIFT trace-cmd: Dump fraction bits from TRACECMD_OPTION_TIME_SHIFT .../include/private/trace-cmd-private.h | 4 +- lib/trace-cmd/include/trace-tsync-local.h | 7 +- lib/trace-cmd/trace-input.c | 79 +++++++------- lib/trace-cmd/trace-timesync-kvm.c | 59 +++++++--- lib/trace-cmd/trace-timesync-ptp.c | 4 +- lib/trace-cmd/trace-timesync.c | 49 +++++++-- tracecmd/trace-dump.c | 102 +++++++++++++----- 7 files changed, 205 insertions(+), 99 deletions(-) -- 2.31.1
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