On Tue, Mar 25, 2025 at 1:13 PM Suleiman Souhlal <suleiman@xxxxxxxxxx> wrote: > > This series makes it so that the time that the host is suspended is > included in guests' steal time. Friendly ping. -- Suleiman > > When the host resumes from a suspend, the guest thinks any task > that was running during the suspend ran for a long time, even though > the effective run time was much shorter, which can end up having > negative effects with scheduling. > > To mitigate this issue, we include the time that the host was > suspended in steal time, which lets the guest can subtract the > duration from the tasks' runtime. > > In addition, we make the guest TSC behavior consistent whether the > host TSC went backwards or not. > > v5: > - Fix grammar mistakes in commit message. > > v4: https://lore.kernel.org/kvm/20250221053927.486476-1-suleiman@xxxxxxxxxx/T/ > - Advance guest TSC on suspends where host TSC goes backwards. > - Block vCPUs from running until resume notifier. > - Move suspend duration accounting out of machine-independent kvm to > x86. > - Merge code and documentation patches. > - Reworded documentation. > > v3: https://lore.kernel.org/kvm/Z5AB-6bLRNLle27G@xxxxxxxxxx/T/ > - Use PM notifier instead of syscore ops (kvm_suspend()/kvm_resume()), > because the latter doesn't get called on shallow suspend. > - Don't call function under UACCESS. > - Whitespace. > > v2: https://lore.kernel.org/lkml/20241118043745.1857272-1-suleiman@xxxxxxxxxx/ > - Accumulate suspend time at machine-independent kvm layer and track per-VCPU > instead of per-VM. > - Document changes. > > v1: https://lore.kernel.org/kvm/20240710074410.770409-1-suleiman@xxxxxxxxxx/ > > Suleiman Souhlal (2): > KVM: x86: Advance guest TSC after deep suspend. > KVM: x86: Include host suspended time in steal time > > Documentation/virt/kvm/x86/msr.rst | 10 +++- > arch/x86/include/asm/kvm_host.h | 7 +++ > arch/x86/kvm/x86.c | 84 +++++++++++++++++++++++++++++- > 3 files changed, 98 insertions(+), 3 deletions(-) > > -- > 2.49.0.395.g12beb8f557-goog >
