Reduce special casing of xen_cpuid() by using cpu capabilities instead of faked cpuid nodes. This cleanup enables us remove the hypervisor specific set_cpu_features callback as the same effect can be reached via setup_[clear|force]_cpu_cap(). Removing the rest faked nodes from xen_cpuid() requires some more work as the remaining cases (mwait leafs and extended topology info) have to be handled at the consumer sides of this information. Changes in V3: - rewrite patch 9 (xsave) to use xgetbv instruction to test for osxsave availability (Andrew Cooper) Changes in V2: - added several features to this scheme - removed hypervisor specific set_cpu_features() callbacks Cc: Alok Kataria <akataria at vmware.com> Cc: Thomas Gleixner <tglx at linutronix.de> Cc: Ingo Molnar <mingo at redhat.com> Cc: "H. Peter Anvin" <hpa at zytor.com> Cc: x86 at kernel.org Cc: virtualization at lists.linux-foundation.org Juergen Gross (11): xen: set cpu capabilities from xen_start_kernel() x86/xen: don't indicate DCA support in pv domains x86/xen: use capabilities instead of fake cpuid values for aperf x86/xen: use capabilities instead of fake cpuid values for mtrr x86/xen: use capabilities instead of fake cpuid values for acc x86/xen: use capabilities instead of fake cpuid values for acpi x86/xen: use capabilities instead of fake cpuid values for mwait x86/xen: use capabilities instead of fake cpuid values for x2apic x86/xen: use capabilities instead of fake cpuid values for xsave vmware: set cpu capabilities during platform initialization x86/cpu: remove hypervisor specific set_cpu_features arch/x86/include/asm/hypervisor.h | 5 --- arch/x86/kernel/cpu/common.c | 1 - arch/x86/kernel/cpu/hypervisor.c | 8 ---- arch/x86/kernel/cpu/vmware.c | 39 ++++++++-------- arch/x86/xen/enlighten_pv.c | 95 +++++++++++++++++---------------------- 5 files changed, 61 insertions(+), 87 deletions(-) -- 2.12.0
Juergen Gross
2017-Apr-18 06:31 UTC
[PATCH v3 10/11] vmware: set cpu capabilities during platform initialization
There is no need to set the same capabilities for each cpu individually. This can be done for all cpus in platform initialization. Cc: Alok Kataria <akataria at vmware.com> Cc: Thomas Gleixner <tglx at linutronix.de> Cc: Ingo Molnar <mingo at redhat.com> Cc: "H. Peter Anvin" <hpa at zytor.com> Cc: x86 at kernel.org Cc: virtualization at lists.linux-foundation.org Signed-off-by: Juergen Gross <jgross at suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky at oracle.com> Acked-by: Alok Kataria <akataria at vmware.com> --- arch/x86/kernel/cpu/vmware.c | 39 ++++++++++++++++++++------------------- 1 file changed, 20 insertions(+), 19 deletions(-) diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c index 22403a28caf5..40ed26852ebd 100644 --- a/arch/x86/kernel/cpu/vmware.c +++ b/arch/x86/kernel/cpu/vmware.c @@ -113,6 +113,24 @@ static void __init vmware_paravirt_ops_setup(void) #define vmware_paravirt_ops_setup() do {} while (0) #endif +/* + * VMware hypervisor takes care of exporting a reliable TSC to the guest. + * Still, due to timing difference when running on virtual cpus, the TSC can + * be marked as unstable in some cases. For example, the TSC sync check at + * bootup can fail due to a marginal offset between vcpus' TSCs (though the + * TSCs do not drift from each other). Also, the ACPI PM timer clocksource + * is not suitable as a watchdog when running on a hypervisor because the + * kernel may miss a wrap of the counter if the vcpu is descheduled for a + * long time. To skip these checks at runtime we set these capability bits, + * so that the kernel could just trust the hypervisor with providing a + * reliable virtual TSC that is suitable for timekeeping. + */ +static void __init vmware_set_capabilities(void) +{ + setup_force_cpu_cap(X86_FEATURE_CONSTANT_TSC); + setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE); +} + static void __init vmware_platform_setup(void) { uint32_t eax, ebx, ecx, edx; @@ -152,6 +170,8 @@ static void __init vmware_platform_setup(void) #ifdef CONFIG_X86_IO_APIC no_timer_check = 1; #endif + + vmware_set_capabilities(); } /* @@ -176,24 +196,6 @@ static uint32_t __init vmware_platform(void) return 0; } -/* - * VMware hypervisor takes care of exporting a reliable TSC to the guest. - * Still, due to timing difference when running on virtual cpus, the TSC can - * be marked as unstable in some cases. For example, the TSC sync check at - * bootup can fail due to a marginal offset between vcpus' TSCs (though the - * TSCs do not drift from each other). Also, the ACPI PM timer clocksource - * is not suitable as a watchdog when running on a hypervisor because the - * kernel may miss a wrap of the counter if the vcpu is descheduled for a - * long time. To skip these checks at runtime we set these capability bits, - * so that the kernel could just trust the hypervisor with providing a - * reliable virtual TSC that is suitable for timekeeping. - */ -static void vmware_set_cpu_features(struct cpuinfo_x86 *c) -{ - set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC); - set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE); -} - /* Checks if hypervisor supports x2apic without VT-D interrupt remapping. */ static bool __init vmware_legacy_x2apic_available(void) { @@ -206,7 +208,6 @@ static bool __init vmware_legacy_x2apic_available(void) const __refconst struct hypervisor_x86 x86_hyper_vmware = { .name = "VMware", .detect = vmware_platform, - .set_cpu_features = vmware_set_cpu_features, .init_platform = vmware_platform_setup, .x2apic_available = vmware_legacy_x2apic_available, }; -- 2.12.0
Maybe Matching Threads
- [PATCH v2 00/11] x86: xen cpuid() cleanup
- [PATCH v2 00/11] x86: xen cpuid() cleanup
- [PATCH v3 00/11] x86: xen cpuid() cleanup
- [PATCH v2 10/11] vmware: set cpu capabilities during platform initialization
- [PATCH] x86, Allow x2apic without IR on VMware platform.