On Fri, 16 Sep 2016 16:56:34 +0200 Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: > On 16/09/2016 16:27, Luiz Capitulino wrote: > > [Introduction will follow] > > > > Changelog > > --------- > > > > v2 > > > > - add tsc_offset field to struct kvm_vcpu_arch > > - drop read_tsc_offset() > > - add per-vcpu dir entries in debugfs > > - export TSC scaling info (besides TSC offset) > > - export the TSC offset as a signed number > > - drop patch that wrongly tried to improve error > > handling in kvm_create_vm_debugfs() > > I've tested this patch on an AMD machine with TSC scaling, so I'm > pushing it shortly to kvm/queue. Thanks for the testing! Btw, I don't mind letting it sit on the list for a few days for review (well, no submitter should mind this). > > Paolo > > > Intro > > ----- > > > > This series exports a VM's TSC offset and TSC scaling > > information to user-space via a new per-vcpu directory > > in debugfs. For example: > > > > /sys/kernel/debug/kvm/66828-10/vcpu0/tsc-offset > > /sys/kernel/debug/kvm/66828-10/vcpu0/tsc-scaling-ratio > > /sys/kernel/debug/kvm/66828-10/vcpu0/tsc-scaling-ratio-frac-bits > > > > The TSC offset in particular is needed in user-space > > in order for tracing tools, such as trace-cmd, to be > > able to merge the host and guest traces using the > > host TSC. This is explained in detail in this thread: > > > > [Qemu-devel] [RFC] host and guest kernel trace merging > > https://lists.nongnu.org/archive/html/qemu-devel/2016-03/msg00887.html > > > > Luiz Capitulino (6): > > kvm: x86: add tsc_offset field to struct kvm_vcpu_arch > > kvm: x86: drop read_tsc_offset() > > kvm: kvm_destroy_vm_debugfs(): check debugfs_stat_data pointer > > kvm: add stubs for arch specific debugfs support > > kvm: create per-vcpu dirs in debugfs > > kvm: x86: export TSC information to user-space > > > > arch/arm/kvm/arm.c | 10 ++++++ > > arch/mips/kvm/mips.c | 10 ++++++ > > arch/powerpc/kvm/powerpc.c | 10 ++++++ > > arch/s390/kvm/kvm-s390.c | 10 ++++++ > > arch/x86/include/asm/kvm_host.h | 2 +- > > arch/x86/kvm/Makefile | 2 +- > > arch/x86/kvm/debugfs.c | 69 +++++++++++++++++++++++++++++++++++++++++ > > arch/x86/kvm/svm.c | 8 ----- > > arch/x86/kvm/vmx.c | 6 ---- > > arch/x86/kvm/x86.c | 12 +++++-- > > include/linux/kvm_host.h | 4 +++ > > virt/kvm/kvm_main.c | 40 ++++++++++++++++++++++-- > > 12 files changed, 161 insertions(+), 22 deletions(-) > > create mode 100644 arch/x86/kvm/debugfs.c > > > -- 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
