Messages in this thread | | | Date | Wed, 4 Jul 2012 23:37:46 -0300 | From | Marcelo Tosatti <> | Subject | Re: [PATCH v2 5/7] KVM: Introduce PV kick in flush tlb |
| |
On Tue, Jul 03, 2012 at 01:55:02PM +0530, Nikunj A Dadhania wrote: > On Tue, 3 Jul 2012 05:07:13 -0300, Marcelo Tosatti <mtosatti@redhat.com> wrote: > > On Mon, Jun 04, 2012 at 10:38:17AM +0530, Nikunj A. Dadhania wrote: > > > In place of looping continuously introduce a halt if we do not succeed > > > after some time. > > > > > > For vcpus that were running an IPI is sent. In case, it went to sleep > > > between this, we will be doing flush_on_enter(harmless). But as a > > > flush IPI was already sent, that will be processed in ipi handler, > > > this might result into something undesireable, i.e. It might clear the > > > flush_mask of a new request. > > > > > > So after sending an IPI and waiting for a while, do a halt and wait > > > for a kick from the last vcpu. > > > > > > Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> > > > Signed-off-by: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com> > > > > Again, was it determined that this is necessary from data of > > benchmarking on the in-guest-mode/out-guest-mode patch? > > > No, this is more of a fix wrt algo.
Please have numbers for the improvement relative to the previous patch.
It introduces a dependency, these (pvtlbflush and pvspinlocks) are separate features. It is useful to switch them on/off individually.
| |