On Tue, 09 Feb 2021 13:24:23 +0100 Dario Faggioli <dfaggioli@xxxxxxxx> wrote: > > BTW, if I can pester you a little bit more, now that it works I'm > trying to use this, and here's what I'm doing. > > == VM: > # echo tsc > /sys/devices/system/clocksource/clocksource0/current_clocksource > # echo x86-tsc > /sys/kernel/tracing/trace_clock > # trace-cmd agent > > == Host: > # echo x86-tsc > /sys/kernel/tracing/trace_clock > # trace-cmd record -p nop -e sched:* -e kvm:* -e timer:hrtimer* -A tumbleweed-jeos:823 -e sched:* -e syscalls:*_clock_nanosleep -e timer:hrtimer* sleep 1 > Note you can use -C x86-tsc on the command line which would handle the clocks for you. I believe it may update the agent as well, but if not, you can add it to the agent as well. Also "-p nop" shouldn't be needed, as that would happen automatically if "-p" is left off. trace-cmd record -e sched -e kvm -e 'hrtimer*' -C x86-tsc \ -A tumbleweed-jeos:823 -e sched -e '*_clock_nanosleep' -e 'hrtimer*' \ sleep 1 should be equivalent. You may need to add '-C x86-tsc' after the -A, but I think we made it match the host if a clock was supplied. > And I do end up with the two files: trace.dat for the host and trace- > (null).dat (oh, well :-D) for the guest. I believe my latest push should fix that ;-) -- Steve
|