search for: calibrate_tsc

Re-factor the vmware platform setup code to query the hypervisor for tsc frequency only once during boot. Since the VMware hypervisor guarantees constant TSC, calibrate_tsc now uses the saved value. Signed-off-by: Alexey Makhalov <amakhalov at vmware.com> Acked-by: Alok N Kataria <akataria at vmware.com> --- arch/x86/kernel/cpu/vmware.c | 37 ++++++++++++++++++------------------- 1 file changed, 18 insertions(+), 19 deletions(-) diff --git a/arch/x86/ke...

Re-factor the vmware platform setup code to query the hypervisor for tsc frequency only once during boot. Since the VMware hypervisor guarantees constant TSC, calibrate_tsc now uses the saved value. Signed-off-by: Alexey Makhalov <amakhalov at vmware.com> Acked-by: Alok N Kataria <akataria at vmware.com> --- arch/x86/kernel/cpu/vmware.c | 37 ++++++++++++++++++------------------- 1 file changed, 18 insertions(+), 19 deletions(-) diff --git a/arch/x86/ke...

...platform.calibrate_cpu to native_calibrate_cpu() which looks in cpuid leaf 0x16 or msrs for the cpu frequency. Since we keep the tsc_khz constant (even after vmotion), the cpu_khz and tsc_khz may start diverging. tsc_init() now does cpu_khz = x86_platform.calibrate_cpu(); tsc_khz = x86_platform.calibrate_tsc(); if (tsc_khz == 0) tsc_khz = cpu_khz; else if (abs(cpu_khz - tsc_khz) * 10 > tsc_khz) cpu_khz = tsc_khz; We want the cpu_khz and tsc_khz to be sync even if they diverge less then 10%. This patch resolves this issue by setting x86_platform.calibrate_cpu to vmware_get_tsc_khz(). Signed-o...

...platform.calibrate_cpu to native_calibrate_cpu() which looks in cpuid leaf 0x16 or msrs for the cpu frequency. Since we keep the tsc_khz constant (even after vmotion), the cpu_khz and tsc_khz may start diverging. tsc_init() now does cpu_khz = x86_platform.calibrate_cpu(); tsc_khz = x86_platform.calibrate_tsc(); if (tsc_khz == 0) tsc_khz = cpu_khz; else if (abs(cpu_khz - tsc_khz) * 10 > tsc_khz) cpu_khz = tsc_khz; We want the cpu_khz and tsc_khz to be sync even if they diverge less then 10%. This patch resolves this issue by setting x86_platform.calibrate_cpu to vmware_get_tsc_khz(). Signed-o...

...he msrs to do with your patch? > Since we keep the tsc_khz constant (even after vmotion), the cpu_khz and > tsc_khz may start diverging. Now you talk about vmware related stuff, right? > tsc_init() now does > > cpu_khz = x86_platform.calibrate_cpu(); > tsc_khz = x86_platform.calibrate_tsc(); > if (tsc_khz == 0) > tsc_khz = cpu_khz; > else if (abs(cpu_khz - tsc_khz) * 10 > tsc_khz) > cpu_khz = tsc_khz; And here you copy from the referenced commit. How is that helpful? > > We want the cpu_khz and tsc_khz to be sync even if they diverge less then > 10%....

I believe our trademark guidelines say we aren't supposed to use VMware as a noun to mean a product, only to mean the company. So we can say "running on VMware ESXi" or "running in a VMware virtual machine", but "running on VMware" is wrong. There is supposedly some good legal reason for this related to keeping our trademark. On Tue, 25 Oct 2016 22:26:00 -0700,

I believe our trademark guidelines say we aren't supposed to use VMware as a noun to mean a product, only to mean the company. So we can say "running on VMware ESXi" or "running in a VMware virtual machine", but "running on VMware" is wrong. There is supposedly some good legal reason for this related to keeping our trademark. On Tue, 25 Oct 2016 22:26:00 -0700,

This patchset includes several VMware guest improvements: Alexey Makhalov (3): x86/vmware: Use tsc_khz value for calibrate_cpu() x86/vmware: Add basic paravirt ops support x86/vmware: Add paravirt sched clock Documentation/kernel-parameters.txt | 4 +++ arch/x86/kernel/cpu/vmware.c | 51 +++++++++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+) -- 2.10.1

This patchset includes several VMware guest improvements: Alexey Makhalov (3): x86/vmware: Use tsc_khz value for calibrate_cpu() x86/vmware: Add basic paravirt ops support x86/vmware: Add paravirt sched clock Documentation/kernel-parameters.txt | 4 +++ arch/x86/kernel/cpu/vmware.c | 51 +++++++++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+) -- 2.10.1

...> +#include <asm/apic.h> #define CPUID_VMWARE_INFO_LEAF 0x40000000 #define VMWARE_HYPERVISOR_MAGIC 0x564D5868 @@ -82,10 +83,17 @@ static void __init vmware_platform_setup(void) VMWARE_PORT(GETHZ, eax, ebx, ecx, edx); - if (ebx != UINT_MAX) + if (ebx != UINT_MAX) { x86_platform.calibrate_tsc = vmware_get_tsc_khz; - else +#ifdef CONFIG_X86_LOCAL_APIC + /* Skip lapic calibration since we know the bus frequency. */ + lapic_timer_frequency = ecx / HZ; + pr_info("Host bus clock speed read from hypervisor : %u Hz\n", + ecx); +#endif + } else { pr_warn("Failed to get TS...

...> +#include <asm/apic.h> #define CPUID_VMWARE_INFO_LEAF 0x40000000 #define VMWARE_HYPERVISOR_MAGIC 0x564D5868 @@ -82,10 +83,17 @@ static void __init vmware_platform_setup(void) VMWARE_PORT(GETHZ, eax, ebx, ecx, edx); - if (ebx != UINT_MAX) + if (ebx != UINT_MAX) { x86_platform.calibrate_tsc = vmware_get_tsc_khz; - else +#ifdef CONFIG_X86_LOCAL_APIC + /* Skip lapic calibration since we know the bus frequency. */ + lapic_timer_frequency = ecx / HZ; + pr_info("Host bus clock speed read from hypervisor : %u Hz\n", + ecx); +#endif + } else { pr_warn("Failed to get TS...

Thanks Thomas for the valuable comments. Changelog for the updated patchset: v1->v2 - Update pvinfo.name. v2->v3 - Address comments from Thomas G, * Created separate function: vmware_sched_clock_setup() (patch 3/3) * Updated commit descriptions for 1/3 and 3/3 Alexey Makhalov (3): x86/vmware: Use tsc_khz value for calibrate_cpu() x86/vmware: Add basic paravirt ops support

Thanks Thomas for the valuable comments. Changelog for the updated patchset: v1->v2 - Update pvinfo.name. v2->v3 - Address comments from Thomas G, * Created separate function: vmware_sched_clock_setup() (patch 3/3) * Updated commit descriptions for 1/3 and 3/3 Alexey Makhalov (3): x86/vmware: Use tsc_khz value for calibrate_cpu() x86/vmware: Add basic paravirt ops support

...- x86 hypervisor specific runtime callbacks + * + * @pin_vcpu: pin current vcpu to specified physical cpu (run rarely) + */ +struct x86_hyper_runtime { + void (*pin_vcpu)(int cpu); +}; + +/** * struct x86_platform_ops - platform specific runtime functions * @calibrate_cpu: calibrate CPU * @calibrate_tsc: calibrate TSC, if different from CPU @@ -218,6 +240,7 @@ struct x86_legacy_features { * possible in x86_early_init_platform_quirks() by * only using the current x86_hardware_subarch * semantics. + * @hyper: x86 hypervisor specific runtime callbacks */ struct x86_platform_op...

...get_function(VMI_CALL_CancelAlarm); - x86_init.timers.timer_init = vmi_time_init; -#ifdef CONFIG_X86_LOCAL_APIC - x86_init.timers.setup_percpu_clockev = vmi_time_bsp_init; - x86_cpuinit.setup_percpu_clockev = vmi_time_ap_init; -#endif - pv_time_ops.sched_clock = vmi_sched_clock; - x86_platform.calibrate_tsc = vmi_tsc_khz; - x86_platform.get_wallclock = vmi_get_wallclock; - x86_platform.set_wallclock = vmi_set_wallclock; - - /* We have true wallclock functions; disable CMOS clock sync */ - no_sync_cmos_clock = 1; - } else { - disable_noidle = 1; - disable_vmi_timer = 1; - } - - para_fill(pv_irq_o...

...get_function(VMI_CALL_CancelAlarm); - x86_init.timers.timer_init = vmi_time_init; -#ifdef CONFIG_X86_LOCAL_APIC - x86_init.timers.setup_percpu_clockev = vmi_time_bsp_init; - x86_cpuinit.setup_percpu_clockev = vmi_time_ap_init; -#endif - pv_time_ops.sched_clock = vmi_sched_clock; - x86_platform.calibrate_tsc = vmi_tsc_khz; - x86_platform.get_wallclock = vmi_get_wallclock; - x86_platform.set_wallclock = vmi_set_wallclock; - - /* We have true wallclock functions; disable CMOS clock sync */ - no_sync_cmos_clock = 1; - } else { - disable_noidle = 1; - disable_vmi_timer = 1; - } - - para_fill(pv_irq_o...

Booting a Xen PVH guest requires a special boot entry as it is mandatory to setup some Xen-specific interfaces rather early. When grub or OVMF are used as boot loaders, however, those will fill the boot parameters in zeropage and there is no longer a need to do something PVH specific in the early boot path. This patch series adds support for that scenario by identifying PVH environment and doing

Booting a Xen PVH guest requires a special boot entry as it is mandatory to setup some Xen-specific interfaces rather early. When grub or OVMF are used as boot loaders, however, those will fill the boot parameters in zeropage and there is no longer a need to do something PVH specific in the early boot path. This patch series adds support for that scenario by identifying PVH environment and doing