On Sun, Jan 08, 2017 at 03:32:32PM -0200, Eduardo Habkost wrote: > This series makes QEMU accept migration if tsc-frequency is > explicitly set on configuration. As management software is > required to keep device configuration the same on migration > source or destination, explicit tsc-frequency will ensure that > either: > > * The destination host has a matching TSC frequency; or > * The destination host has TSC scaling available. > > Changelog > ========= > > v2 -> v3: > * Fix build failure ((missing closing braces) > > v1 -> v2: > * v1 series subject was: > * [PATCH 0/4] Allow migration with invtsc if there's no > frequency mismatch > * Removed patches 3/4 and 4/4, that allowed migration > if no explicit tsc-frequency was set. Implementing the check on > post_load or post_init is not enough to make migration abort, > so we will need a more complex solution to implement that > feature. > > Plans for future work > ===================== > > 1) Querying host TSC frequency/scaling capability > ------------------------------------------------- > > I plan to include TSC frequency/scaling information on > query-cpu-model-expansion model="host" in a future series. Then > management software will be able to automatically configure TSC > frequency when invtsc is enabled, instead of requiring the user > to configure it explicitly. While we don't implement that, invtsc > migration will be possible only if the user configures TSC > frequency manually. > > 2) invtsc migration with no explicit TSC frequency > -------------------------------------------------- > > A future series can implement migration when TSC frequency is not > specified explicitly. It will be a bit more complex because it > requires either letting the destination abort the migration, or > sending TSC frequency/scaling information from destination to > source. > > --- > Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx> > Cc: "Daniel P. Berrange" <berrange@xxxxxxxxxx> > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> > Cc: kvm@xxxxxxxxxxxxxxx > Cc: Haozhong Zhang <haozhong.zhang@xxxxxxxxx> > Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx> > Cc: Igor Mammedov <imammedo@xxxxxxxxxx> > Cc: libvir-list@xxxxxxxxxx > Cc: Jiri Denemark <jdenemar@xxxxxxxxxx> > > Eduardo Habkost (2): > kvm: Simplify invtsc check > kvm: Allow invtsc migration if tsc-khz is set explicitly > > target/i386/kvm.c | 20 +++++++++++--------- > 1 file changed, 11 insertions(+), 9 deletions(-) > > -- > 2.11.0.259.g40922b1 Looks good to me. -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
