Re: [PATCH 4/4] KVM: vmx: Allow the guest to run with dirty debug registers

2014-02-27 Thread Paolo Bonzini
Il 27/02/2014 12:25, Jan Kiszka ha scritto: On 2014-02-26 16:49, Paolo Bonzini wrote: When not running in guest-debug mode (i.e. the guest controls the debug registers, having to take an exit for each DR access is a waste of time. If the guest gets into a state where each context switch causes D

Re: [PATCH 4/4] KVM: vmx: Allow the guest to run with dirty debug registers

2014-02-27 Thread Jan Kiszka
On 2014-02-26 16:49, Paolo Bonzini wrote: > When not running in guest-debug mode (i.e. the guest controls the debug > registers, having to take an exit for each DR access is a waste of time. > If the guest gets into a state where each context switch causes DR to be > saved and restored, this can ta

[PATCH 4/4] KVM: vmx: Allow the guest to run with dirty debug registers

2014-02-26 Thread Paolo Bonzini
When not running in guest-debug mode (i.e. the guest controls the debug registers, having to take an exit for each DR access is a waste of time. If the guest gets into a state where each context switch causes DR to be saved and restored, this can take away as much as 40% of the execution time from