kernel.git/arch/powerpc/kvm, branch linux-2.6.28.y

KVM: ppc: stop leaking host memory on VM exit

2008-11-25T10:02:48Z

When the VM exits, we must call put_page() for every page referenced in the shadow TLB. Without this patch, we usually leak 30-50 host pages (120 - 200 KiB with 4 KiB pages). The maximum number of pages leaked is the size of our shadow TLB, 64 pages. Signed-off-by: Hollis Blanchard Signed-off-by: Avi Kivity

KVM: switch to get_user_pages_fast

2008-10-15T12:25:06Z

Convert gfn_to_pfn to use get_user_pages_fast, which can do lockless pagetable lookups on x86. Kernel compilation on 4-way guest is 3.7% faster on VMX. Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity

KVM: ppc: kvmppc_44x_shadow_release() does not require mmap_sem to be locked

2008-10-15T08:15:26Z

And it gets in the way of get_user_pages_fast(). Signed-off-by: Hollis Blanchard Signed-off-by: Avi Kivity

KVM: powerpc: Map guest userspace with TID=0 mappings

2008-10-15T08:15:16Z

When we use TID=N userspace mappings, we must ensure that kernel mappings have been destroyed when entering userspace. Using TID=1/TID=0 for kernel/user mappings and running userspace with PID=0 means that userspace can't access the kernel mappings, but the kernel can directly access userspace. The net is that we don't need to flush the TLB on privilege switches, but we do on guest context switches (which are far more infrequent). Guest boot time performance improvement: about 30%. Signed-off-by: Hollis Blanchard Signed-off-by: Avi Kivity

KVM: ppc: Write only modified shadow entries into the TLB on exit

2008-10-15T08:15:16Z

Track which TLB entries need to be written, instead of overwriting everything below the high water mark. Typically only a single guest TLB entry will be modified in a single exit. Guest boot time performance improvement: about 15%. Signed-off-by: Hollis Blanchard Signed-off-by: Avi Kivity

KVM: ppc: Stop saving host TLB state

2008-10-15T08:15:16Z

We're saving the host TLB state to memory on every exit, but never using it. Originally I had thought that we'd want to restore host TLB for heavyweight exits, but that could actually hurt when context switching to an unrelated host process (i.e. not qemu). Since this decreases the performance penalty of all exits, this patch improves guest boot time by about 15%. Signed-off-by: Hollis Blanchard Signed-off-by: Avi Kivity

KVM: ppc: guest breakpoint support

2008-10-15T08:15:16Z

Allow host userspace to program hardware debug registers to set breakpoints inside guests. Signed-off-by: Jerone Young Signed-off-by: Hollis Blanchard Signed-off-by: Avi Kivity

KVM: ppc: trace powerpc instruction emulation

2008-10-15T08:15:15Z

This patch adds a trace point for the instruction emulation on embedded powerpc utilizing the KVM_TRACE interface. Signed-off-by: Christian Ehrhardt Signed-off-by: Avi Kivity

KVM: ppc: adds trace points for ppc tlb activity

2008-10-15T08:15:15Z

This patch adds trace points to track powerpc TLB activities using the KVM_TRACE infrastructure. Signed-off-by: Jerone Young Signed-off-by: Christian Ehrhardt Signed-off-by: Avi Kivity

KVM: ppc: enable KVM_TRACE building for powerpc

2008-10-15T08:15:15Z

This patch enables KVM_TRACE to build for PowerPC arch. This means just adding sections to Kconfig and Makefile. Signed-off-by: Jerone Young Signed-off-by: Christian Ehrhardt Signed-off-by: Avi Kivity