| Message ID | 20200131174930.31045-12-liuwe@microsoft.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | More Hyper-V infrastructures | expand |
> -----Original Message----- > From: Wei Liu <wei.liu.xen@gmail.com> On Behalf Of Wei Liu > Sent: 31 January 2020 17:50 > To: Xen Development List <xen-devel@lists.xenproject.org> > Cc: Durrant, Paul <pdurrant@amazon.co.uk>; Michael Kelley > <mikelley@microsoft.com>; Wei Liu <liuwe@microsoft.com>; Wei Liu > <wl@xen.org>; Jan Beulich <jbeulich@suse.com>; Andrew Cooper > <andrew.cooper3@citrix.com>; Roger Pau Monné <roger.pau@citrix.com> > Subject: [PATCH v6 11/11] x86/hyperv: setup VP assist page > > VP assist page is rather important as we need to toggle some bits in it > for efficient nested virtualisation. > > Signed-off-by: Wei Liu <liuwe@microsoft.com> Reviewed-by: Paul Durrant <pdurrant@amazon.com> > --- > v6: > 1. Use hv_vp_assist_page_msr > 2. Make code shorter > 3. Preserve rsvdP fields > > v5: > 1. Deal with error properly instead of always panicking > 2. Swap percpu variables declarations' location > > v4: > 1. Use private.h > 2. Prevent leak > > v3: > 1. Use xenheap page > 2. Drop set_vp_assist > > v2: > 1. Use HV_HYP_PAGE_SHIFT instead > --- > xen/arch/x86/guest/hyperv/hyperv.c | 37 ++++++++++++++++++++++++++++- > xen/arch/x86/guest/hyperv/private.h | 1 + > 2 files changed, 37 insertions(+), 1 deletion(-) > > diff --git a/xen/arch/x86/guest/hyperv/hyperv.c > b/xen/arch/x86/guest/hyperv/hyperv.c > index 6dac3bfceb..75fb329d4d 100644 > --- a/xen/arch/x86/guest/hyperv/hyperv.c > +++ b/xen/arch/x86/guest/hyperv/hyperv.c > @@ -31,6 +31,7 @@ > > struct ms_hyperv_info __read_mostly ms_hyperv; > DEFINE_PER_CPU_READ_MOSTLY(void *, hv_input_page); > +DEFINE_PER_CPU_READ_MOSTLY(void *, hv_vp_assist); > DEFINE_PER_CPU_READ_MOSTLY(unsigned int, hv_vp_index); > > static uint64_t generate_guest_id(void) > @@ -155,17 +156,51 @@ static int setup_hypercall_pcpu_arg(void) > return 0; > } > > +static int setup_vp_assist(void) > +{ > + union hv_vp_assist_page_msr msr; > + > + if ( !this_cpu(hv_vp_assist) ) > + { > + this_cpu(hv_vp_assist) = alloc_xenheap_page(); > + if ( !this_cpu(hv_vp_assist) ) > + { > + printk("CPU%u: Failed to allocate vp_assist page\n", > + smp_processor_id()); > + return -ENOMEM; > + } > + > + clear_page(this_cpu(hv_vp_assist)); > + } > + > + rdmsrl(HV_X64_MSR_VP_ASSIST_PAGE, msr.raw); > + msr.pfn = virt_to_mfn(this_cpu(hv_vp_assist)); > + msr.enabled = 1; > + wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, msr.raw); > + > + return 0; > +} > + > static void __init setup(void) > { > setup_hypercall_page(); > > if ( setup_hypercall_pcpu_arg() ) > panic("Hyper-V hypercall percpu arg setup failed\n"); > + > + if ( setup_vp_assist() ) > + panic("VP assist page setup failed\n"); > } > > static int ap_setup(void) > { > - return setup_hypercall_pcpu_arg(); > + int rc; > + > + rc = setup_hypercall_pcpu_arg(); > + if ( rc ) > + return rc; > + > + return setup_vp_assist(); > } > > static void __init e820_fixup(struct e820map *e820) > diff --git a/xen/arch/x86/guest/hyperv/private.h > b/xen/arch/x86/guest/hyperv/private.h > index d1765d4f23..956eff831f 100644 > --- a/xen/arch/x86/guest/hyperv/private.h > +++ b/xen/arch/x86/guest/hyperv/private.h > @@ -25,6 +25,7 @@ > #include <xen/percpu.h> > > DECLARE_PER_CPU(void *, hv_input_page); > +DECLARE_PER_CPU(void *, hv_vp_assist); > DECLARE_PER_CPU(unsigned int, hv_vp_index); > > #endif /* __XEN_HYPERV_PRIVIATE_H__ */ > -- > 2.20.1
On Fri, Jan 31, 2020 at 05:49:30PM +0000, Wei Liu wrote: > VP assist page is rather important as we need to toggle some bits in it > for efficient nested virtualisation. > > Signed-off-by: Wei Liu <liuwe@microsoft.com> Reviewed-by: Roger Pau Monné <roger.pau@citrix.com> Thanks, Roger.
diff --git a/xen/arch/x86/guest/hyperv/hyperv.c b/xen/arch/x86/guest/hyperv/hyperv.c index 6dac3bfceb..75fb329d4d 100644 --- a/xen/arch/x86/guest/hyperv/hyperv.c +++ b/xen/arch/x86/guest/hyperv/hyperv.c @@ -31,6 +31,7 @@ struct ms_hyperv_info __read_mostly ms_hyperv; DEFINE_PER_CPU_READ_MOSTLY(void *, hv_input_page); +DEFINE_PER_CPU_READ_MOSTLY(void *, hv_vp_assist); DEFINE_PER_CPU_READ_MOSTLY(unsigned int, hv_vp_index); static uint64_t generate_guest_id(void) @@ -155,17 +156,51 @@ static int setup_hypercall_pcpu_arg(void) return 0; } +static int setup_vp_assist(void) +{ + union hv_vp_assist_page_msr msr; + + if ( !this_cpu(hv_vp_assist) ) + { + this_cpu(hv_vp_assist) = alloc_xenheap_page(); + if ( !this_cpu(hv_vp_assist) ) + { + printk("CPU%u: Failed to allocate vp_assist page\n", + smp_processor_id()); + return -ENOMEM; + } + + clear_page(this_cpu(hv_vp_assist)); + } + + rdmsrl(HV_X64_MSR_VP_ASSIST_PAGE, msr.raw); + msr.pfn = virt_to_mfn(this_cpu(hv_vp_assist)); + msr.enabled = 1; + wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, msr.raw); + + return 0; +} + static void __init setup(void) { setup_hypercall_page(); if ( setup_hypercall_pcpu_arg() ) panic("Hyper-V hypercall percpu arg setup failed\n"); + + if ( setup_vp_assist() ) + panic("VP assist page setup failed\n"); } static int ap_setup(void) { - return setup_hypercall_pcpu_arg(); + int rc; + + rc = setup_hypercall_pcpu_arg(); + if ( rc ) + return rc; + + return setup_vp_assist(); } static void __init e820_fixup(struct e820map *e820) diff --git a/xen/arch/x86/guest/hyperv/private.h b/xen/arch/x86/guest/hyperv/private.h index d1765d4f23..956eff831f 100644 --- a/xen/arch/x86/guest/hyperv/private.h +++ b/xen/arch/x86/guest/hyperv/private.h @@ -25,6 +25,7 @@ #include <xen/percpu.h> DECLARE_PER_CPU(void *, hv_input_page); +DECLARE_PER_CPU(void *, hv_vp_assist); DECLARE_PER_CPU(unsigned int, hv_vp_index); #endif /* __XEN_HYPERV_PRIVIATE_H__ */
VP assist page is rather important as we need to toggle some bits in it for efficient nested virtualisation. Signed-off-by: Wei Liu <liuwe@microsoft.com> --- v6: 1. Use hv_vp_assist_page_msr 2. Make code shorter 3. Preserve rsvdP fields v5: 1. Deal with error properly instead of always panicking 2. Swap percpu variables declarations' location v4: 1. Use private.h 2. Prevent leak v3: 1. Use xenheap page 2. Drop set_vp_assist v2: 1. Use HV_HYP_PAGE_SHIFT instead --- xen/arch/x86/guest/hyperv/hyperv.c | 37 ++++++++++++++++++++++++++++- xen/arch/x86/guest/hyperv/private.h | 1 + 2 files changed, 37 insertions(+), 1 deletion(-)