On Fri, Nov 19, 2021 at 11:21:17AM +0100, Nicolas Saenz Julienne wrote: > Add a new arm64-specific trace clock using the cntvct register, similar > to x64-tsc. This gives us: > - A clock that is relatively fast (1GHz on armv8.6, 1-50MHz otherwise), > monotonic, and resilient to low power modes. > - It can be used to correlate events across cpus as well as across > hypervisor and guests. > > By using arch_timer_read_counter() we make sure that armv8.6 cpus use > the less expensive CNTVCTSS_EL0, which cannot be accessed speculatively. Can this register be read by userspace ? (otherwise it won't be possible to correlate userspace events). _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
