On 06/07/16 08:52, Peter Zijlstra wrote:> On Tue, Jun 28, 2016 at 10:43:07AM -0400, Pan Xinhui wrote: >> change fomr v1: >> a simplier definition of default vcpu_is_preempted >> skip mahcine type check on ppc, and add config. remove dedicated macro. >> add one patch to drop overload of rwsem_spin_on_owner and mutex_spin_on_owner. >> add more comments >> thanks boqun and Peter's suggestion. >> >> This patch set aims to fix lock holder preemption issues. >> >> test-case: >> perf record -a perf bench sched messaging -g 400 -p && perf report >> >> 18.09% sched-messaging [kernel.vmlinux] [k] osq_lock >> 12.28% sched-messaging [kernel.vmlinux] [k] rwsem_spin_on_owner >> 5.27% sched-messaging [kernel.vmlinux] [k] mutex_unlock >> 3.89% sched-messaging [kernel.vmlinux] [k] wait_consider_task >> 3.64% sched-messaging [kernel.vmlinux] [k] _raw_write_lock_irq >> 3.41% sched-messaging [kernel.vmlinux] [k] mutex_spin_on_owner.is >> 2.49% sched-messaging [kernel.vmlinux] [k] system_call >> >> We introduce interface bool vcpu_is_preempted(int cpu) and use it in some spin >> loops of osq_lock, rwsem_spin_on_owner and mutex_spin_on_owner. >> These spin_on_onwer variant also cause rcu stall before we apply this patch set >> > > Paolo, could you help out with an (x86) KVM interface for this?Xen support of this interface should be rather easy. Could you please Cc: xen-devel-request at lists.xenproject.org in the next version? Juergen
On Wed, Jul 06, 2016 at 09:47:18AM +0200, Juergen Gross wrote:> On 06/07/16 08:52, Peter Zijlstra wrote:> > Paolo, could you help out with an (x86) KVM interface for this? > > Xen support of this interface should be rather easy. Could you please > Cc: xen-devel-request at lists.xenproject.org in the next version?So meta question; aren't all you virt people looking at the regular virtualization list? Or should we really dig out all the various hypervisor lists and Cc them?
On 06/07/16 10:19, Peter Zijlstra wrote:> On Wed, Jul 06, 2016 at 09:47:18AM +0200, Juergen Gross wrote: >> On 06/07/16 08:52, Peter Zijlstra wrote: > >>> Paolo, could you help out with an (x86) KVM interface for this? >> >> Xen support of this interface should be rather easy. Could you please >> Cc: xen-devel-request at lists.xenproject.org in the next version? > > So meta question; aren't all you virt people looking at the regular > virtualization list? Or should we really dig out all the various > hypervisor lists and Cc them?Hmm, good question. Up to now I didn't look at the virtualization list, just changed that. :-) Can't speak for the other virt people. Juergen
On 06/07/2016 10:19, Peter Zijlstra wrote:>>> Paolo, could you help out with an (x86) KVM interface for this? >> > >> > Xen support of this interface should be rather easy. Could you please >> > Cc: xen-devel-request at lists.xenproject.org in the next version? > So meta question; aren't all you virt people looking at the regular > virtualization list? Or should we really dig out all the various > hypervisor lists and Cc them?I at least skim the subjects. Paolo
On 07/06/2016 10:19 AM, Peter Zijlstra wrote:> On Wed, Jul 06, 2016 at 09:47:18AM +0200, Juergen Gross wrote: >> On 06/07/16 08:52, Peter Zijlstra wrote: > >>> Paolo, could you help out with an (x86) KVM interface for this? >> >> Xen support of this interface should be rather easy. Could you please >> Cc: xen-devel-request at lists.xenproject.org in the next version? > > So meta question; aren't all you virt people looking at the regular > virtualization list? Or should we really dig out all the various > hypervisor lists and Cc them? >Some of the kvm on s390 team reads this, but I would assume that the base s390 team does not (Martin can you confirm?) as the main focus was z/VM and LPAR. So maybe adding linux-s390 at vger for generic things does make sense.