* Michael S. Tsirkin <mst@xxxxxxxxxx> wrote: > On Mon, May 07, 2012 at 12:35:12PM +0200, Ingo Molnar wrote: > > > Michael S. Tsirkin (5): > > > apic: fix typo EIO_ACK -> EOI_ACK and document > > > apic: use symbolic APIC_EOI_ACK > > > x86: add apic->eoi_write callback > > > x86: eoi micro-optimization > > > kvm_para: guest side for eoi avoidance > > > > > > arch/x86/include/asm/apic.h | 22 ++++++++++++-- > > > arch/x86/include/asm/apicdef.h | 2 +- > > > arch/x86/include/asm/bitops.h | 6 ++- > > > arch/x86/include/asm/kvm_para.h | 2 + > > > arch/x86/kernel/apic/apic_flat_64.c | 2 + > > > arch/x86/kernel/apic/apic_noop.c | 1 + > > > arch/x86/kernel/apic/apic_numachip.c | 1 + > > > arch/x86/kernel/apic/bigsmp_32.c | 1 + > > > arch/x86/kernel/apic/es7000_32.c | 2 + > > > arch/x86/kernel/apic/numaq_32.c | 1 + > > > arch/x86/kernel/apic/probe_32.c | 1 + > > > arch/x86/kernel/apic/summit_32.c | 1 + > > > arch/x86/kernel/apic/x2apic_cluster.c | 1 + > > > arch/x86/kernel/apic/x2apic_phys.c | 1 + > > > arch/x86/kernel/apic/x2apic_uv_x.c | 1 + > > > arch/x86/kernel/kvm.c | 51 ++++++++++++++++++++++++++++++-- > > > arch/x86/platform/visws/visws_quirks.c | 2 +- > > > 17 files changed, 88 insertions(+), 10 deletions(-) > > > > No objections from the x86 side. > > Is kvm.git a good tree to merge this through? Fine to me, but I haven't checked how widely it conflicts with existing bits: by the looks of it most of the linecount is on the core x86 side, while the kvm change is well concentrated. > > In terms of advantages, could you please create perf stat > > runs that counts the number of MMIOs or so? That should show > > a pretty obvious improvement - and that is enough as proof, > > no need to try to reproduce the performance win in a noisy > > benchmark. > > You mean with kvm PV, right? On real hardware the > micro-optimization removes branches and maybe cache-misses but > I don't see why would it reduce MMIOs. Yeah, on KVM. On real hw I doubt it's measurable. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
