This patchset adds support for VMX TSC scaling feature which is available on Intel Skylake Server CPU. The specification of VMX TSC scaling can be found at http://www.intel.com/content/www/us/en/processors/timestamp-counter-scaling-virtualization-white-paper.html
VMX TSC scaling allows guest TSC which is read by guest rdtsc(p) instructions increases in a rate that is customized by the hypervisor and can be different than the host TSC frequency. Basically, VMX TSC scaling adds a 64-bit field called TSC multiplier in VMCS so that, if VMX TSC scaling is enabled, TSC read by guest rdtsc(p) instructions will be calculated by the following formula: guest EDX:EAX = (Host TSC * TSC multiplier) >> 48 + VMX TSC Offset where, Host TSC = Host MSR_IA32_TSC + Host MSR_IA32_TSC_ADJUST. If the destination host supports VMX TSC scaling, this patchset allows guest programs in a HVM container in the default TSC mode or PVRDTSCP (native_paravirt) TSC mode to observe the same TSC frequency across the migration. Changes in v4: * v3 patch 1&2 have been committed so they are not included in v4. * v3 patch 11 "x86/hvm: Detect TSC scaling through hvm_funcs" is merged early into v4 patch 4 "x86/hvm: Collect information of TSC scaling ratio". * v4 patch 1 - 8 correspond to v3 patch 3 - 10. v4 patch 9 - 10 correspond to v3 patch 12 - 13. * Other changes are logged in each patch respectively. Changes in v3: * v2 patch 1&2 have been merged so they do not appear in v3. * Patch 1 - 6 correspond to v2 patch 3 - 8. Patch 7 is new. Patch 8 - 13 correspond to v2 patch 9 - 14. * Other changes are logged in each patch respectively. Changes in v2: * Remove unnecessary v1 patch 1&13. * Add and move all bug-fix patches to the beginning of this series. (Patch 1 - 6) * Update changes in tsc_set_info() and tsc_get_info() to make both functions consistent with each other. (Patch 2 - 4) * Move a part of scaling logic out of [vmx|svm]_set_tsc_offset(). (Patch 7) * Remove redundant hvm_funcs.tsc_scaling_ratio_rsvd. (Patch 8) * Reimplement functions that calculate TSC ratio and scale TSC. (Patch 9&10) * Merge setting VMX TSC multiplier into patch 13. * Move initialing tsc_scaling_ratio in VMX ahead to vmx_vcpu_initialise() so as to make construct_vmcs() naturally use this field instead of a constant. (Patch 13) * Update documents related to tsc_mode. * Other code cleanup and style fixes. Haozhong Zhang (10): x86/hvm: Scale host TSC when setting/getting guest TSC x86/time.c: Scale host TSC in pvclock properly svm: Remove redundant TSC scaling in svm_set_tsc_offset() x86/hvm: Collect information of TSC scaling ratio x86: Add functions for 64-bit integer arithmetic x86/hvm: Setup TSC scaling ratio x86/hvm: Replace architecture TSC scaling by a common function x86/hvm: Move saving/loading vcpu's TSC to common code vmx: Add VMX RDTSC(P) scaling support docs: Add descriptions of TSC scaling in xl.cfg and tscmode.txt docs/man/xl.cfg.pod.5 | 14 +++++++- docs/misc/tscmode.txt | 21 ++++++++++++ xen/arch/x86/hvm/hvm.c | 69 ++++++++++++++++++++++++++++++++------ xen/arch/x86/hvm/svm/svm.c | 36 +++++++++----------- xen/arch/x86/hvm/vmx/vmcs.c | 12 +++++-- xen/arch/x86/hvm/vmx/vmx.c | 25 +++++++++++--- xen/arch/x86/time.c | 38 ++++++++++++++++----- xen/include/asm-x86/hvm/hvm.h | 20 +++++++++++ xen/include/asm-x86/hvm/svm/svm.h | 3 -- xen/include/asm-x86/hvm/vcpu.h | 2 ++ xen/include/asm-x86/hvm/vmx/vmcs.h | 7 ++++ xen/include/asm-x86/math64.h | 47 ++++++++++++++++++++++++++ 12 files changed, 242 insertions(+), 52 deletions(-) create mode 100644 xen/include/asm-x86/math64.h -- 2.7.0 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
