* [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit @ 2018-02-08 9:44 Wanpeng Li 2018-02-08 18:12 ` Eduardo Habkost 2018-02-09 8:41 ` Paolo Bonzini 0 siblings, 2 replies; 11+ messages in thread From: Wanpeng Li @ 2018-02-08 9:44 UTC (permalink / raw) To: qemu-devel, kvm Cc: Paolo Bonzini, Radim Krčmář, Eduardo Habkost From: Wanpeng Li <wanpengli@tencent.com> Add PV_DEDICATED hint cpuid feature bit. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> --- target/i386/cpu.c | 4 ++++ target/i386/cpu.h | 3 +++ 2 files changed, 7 insertions(+) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index d70954b..cf48931 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) x86_cpu_get_supported_feature_word(w, false); uint32_t requested_features = env->features[w]; env->features[w] &= host_feat; + if (cpu->pv_dedicated && (w == FEAT_KVM)) { + env->features[w] |= CPUID_PV_DEDICATED; + } cpu->filtered_features[w] = requested_features & ~env->features[w]; if (cpu->filtered_features[w]) { rv = 1; @@ -4682,6 +4685,7 @@ static Property x86_cpu_properties[] = { false), DEFINE_PROP_BOOL("vmware-cpuid-freq", X86CPU, vmware_cpuid_freq, true), DEFINE_PROP_BOOL("tcg-cpuid", X86CPU, expose_tcg, true), + DEFINE_PROP_BOOL("pv-dedicated", X86CPU, pv_dedicated, false), /* * From "Requirements for Implementing the Microsoft diff --git a/target/i386/cpu.h b/target/i386/cpu.h index f91e37d..8000da5 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -672,6 +672,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; #define CPUID_8000_0008_EBX_IBPB (1U << 12) /* Indirect Branch Prediction Barrier */ +#define CPUID_PV_DEDICATED (1U << 8) + #define CPUID_XSAVE_XSAVEOPT (1U << 0) #define CPUID_XSAVE_XSAVEC (1U << 1) #define CPUID_XSAVE_XGETBV1 (1U << 2) @@ -1276,6 +1278,7 @@ struct X86CPU { bool expose_kvm; bool expose_tcg; bool migratable; + bool pv_dedicated; bool max_features; /* Enable all supported features automatically */ uint32_t apic_id; -- 2.7.4 ^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-08 9:44 [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit Wanpeng Li @ 2018-02-08 18:12 ` Eduardo Habkost 2018-02-09 3:18 ` Wanpeng Li 2018-02-09 8:41 ` Paolo Bonzini 2018-02-09 8:41 ` Paolo Bonzini 1 sibling, 2 replies; 11+ messages in thread From: Eduardo Habkost @ 2018-02-08 18:12 UTC (permalink / raw) To: Wanpeng Li; +Cc: qemu-devel, kvm, Paolo Bonzini, Radim Krčmář On Thu, Feb 08, 2018 at 05:44:20PM +0800, Wanpeng Li wrote: > From: Wanpeng Li <wanpengli@tencent.com> > > Add PV_DEDICATED hint cpuid feature bit. > [...] > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index d70954b..cf48931 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) > x86_cpu_get_supported_feature_word(w, false); > uint32_t requested_features = env->features[w]; > env->features[w] &= host_feat; > + if (cpu->pv_dedicated && (w == FEAT_KVM)) { > + env->features[w] |= CPUID_PV_DEDICATED; > + } Why do this trick here instead of just adding "pv-dedicated" to feature_word_info[FEAT_KVM].feat_names? > [...] -- Eduardo ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-08 18:12 ` Eduardo Habkost @ 2018-02-09 3:18 ` Wanpeng Li 2018-02-09 8:41 ` Paolo Bonzini 1 sibling, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2018-02-09 3:18 UTC (permalink / raw) To: Eduardo Habkost Cc: qemu-devel@nongnu.org Developers, kvm, Paolo Bonzini, Radim Krčmář 2018-02-09 2:12 GMT+08:00 Eduardo Habkost <ehabkost@redhat.com>: > On Thu, Feb 08, 2018 at 05:44:20PM +0800, Wanpeng Li wrote: >> From: Wanpeng Li <wanpengli@tencent.com> >> >> Add PV_DEDICATED hint cpuid feature bit. >> > [...] >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> index d70954b..cf48931 100644 >> --- a/target/i386/cpu.c >> +++ b/target/i386/cpu.c >> @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) >> x86_cpu_get_supported_feature_word(w, false); >> uint32_t requested_features = env->features[w]; >> env->features[w] &= host_feat; >> + if (cpu->pv_dedicated && (w == FEAT_KVM)) { >> + env->features[w] |= CPUID_PV_DEDICATED; >> + } > > Why do this trick here instead of just adding "pv-dedicated" to > feature_word_info[FEAT_KVM].feat_names? Actually this hint doesn't depend on KVM, just qemu command-line gives a hint and then guest kernel can recognize it. Is there a nicer proposal in qemu? Paolo? Regards, Wanpeng Li ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-08 18:12 ` Eduardo Habkost 2018-02-09 3:18 ` Wanpeng Li @ 2018-02-09 8:41 ` Paolo Bonzini 2018-02-09 11:46 ` Eduardo Habkost 1 sibling, 1 reply; 11+ messages in thread From: Paolo Bonzini @ 2018-02-09 8:41 UTC (permalink / raw) To: Eduardo Habkost, Wanpeng Li; +Cc: qemu-devel, kvm, Radim Krčmář On 08/02/2018 19:12, Eduardo Habkost wrote: > On Thu, Feb 08, 2018 at 05:44:20PM +0800, Wanpeng Li wrote: >> From: Wanpeng Li <wanpengli@tencent.com> >> >> Add PV_DEDICATED hint cpuid feature bit. >> > [...] >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> index d70954b..cf48931 100644 >> --- a/target/i386/cpu.c >> +++ b/target/i386/cpu.c >> @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) >> x86_cpu_get_supported_feature_word(w, false); >> uint32_t requested_features = env->features[w]; >> env->features[w] &= host_feat; >> + if (cpu->pv_dedicated && (w == FEAT_KVM)) { >> + env->features[w] |= CPUID_PV_DEDICATED; >> + } > > Why do this trick here instead of just adding "pv-dedicated" to > feature_word_info[FEAT_KVM].feat_names? I think because it can be added independent of KVM_GET_SUPPORTED_CPUID. Paolo ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-09 8:41 ` Paolo Bonzini @ 2018-02-09 11:46 ` Eduardo Habkost 2018-02-09 12:24 ` Wanpeng Li 0 siblings, 1 reply; 11+ messages in thread From: Eduardo Habkost @ 2018-02-09 11:46 UTC (permalink / raw) To: Paolo Bonzini; +Cc: Wanpeng Li, qemu-devel, kvm, Radim Krčmář On Fri, Feb 09, 2018 at 09:41:41AM +0100, Paolo Bonzini wrote: > On 08/02/2018 19:12, Eduardo Habkost wrote: > > On Thu, Feb 08, 2018 at 05:44:20PM +0800, Wanpeng Li wrote: > >> From: Wanpeng Li <wanpengli@tencent.com> > >> > >> Add PV_DEDICATED hint cpuid feature bit. > >> > > [...] > >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c > >> index d70954b..cf48931 100644 > >> --- a/target/i386/cpu.c > >> +++ b/target/i386/cpu.c > >> @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) > >> x86_cpu_get_supported_feature_word(w, false); > >> uint32_t requested_features = env->features[w]; > >> env->features[w] &= host_feat; > >> + if (cpu->pv_dedicated && (w == FEAT_KVM)) { > >> + env->features[w] |= CPUID_PV_DEDICATED; > >> + } > > > > Why do this trick here instead of just adding "pv-dedicated" to > > feature_word_info[FEAT_KVM].feat_names? > > I think because it can be added independent of KVM_GET_SUPPORTED_CPUID. If QEMU knows it can be enabled if outside GET_SUPPORTED_CPUID, kvm_arch_get_supported_cpuid() can return it as supported. -- Eduardo ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-09 11:46 ` Eduardo Habkost @ 2018-02-09 12:24 ` Wanpeng Li 2018-02-09 12:46 ` Paolo Bonzini 2018-02-09 12:46 ` Eduardo Habkost 0 siblings, 2 replies; 11+ messages in thread From: Wanpeng Li @ 2018-02-09 12:24 UTC (permalink / raw) To: Eduardo Habkost Cc: Paolo Bonzini, qemu-devel@nongnu.org Developers, kvm, Radim Krčmář 2018-02-09 19:46 GMT+08:00 Eduardo Habkost <ehabkost@redhat.com>: > On Fri, Feb 09, 2018 at 09:41:41AM +0100, Paolo Bonzini wrote: >> On 08/02/2018 19:12, Eduardo Habkost wrote: >> > On Thu, Feb 08, 2018 at 05:44:20PM +0800, Wanpeng Li wrote: >> >> From: Wanpeng Li <wanpengli@tencent.com> >> >> >> >> Add PV_DEDICATED hint cpuid feature bit. >> >> >> > [...] >> >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> >> index d70954b..cf48931 100644 >> >> --- a/target/i386/cpu.c >> >> +++ b/target/i386/cpu.c >> >> @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) >> >> x86_cpu_get_supported_feature_word(w, false); >> >> uint32_t requested_features = env->features[w]; >> >> env->features[w] &= host_feat; >> >> + if (cpu->pv_dedicated && (w == FEAT_KVM)) { >> >> + env->features[w] |= CPUID_PV_DEDICATED; >> >> + } >> > >> > Why do this trick here instead of just adding "pv-dedicated" to >> > feature_word_info[FEAT_KVM].feat_names? >> >> I think because it can be added independent of KVM_GET_SUPPORTED_CPUID. > > If QEMU knows it can be enabled if outside GET_SUPPORTED_CPUID, > kvm_arch_get_supported_cpuid() can return it as supported. The guest fails to detect the new cpuid this time. diff --git a/target/i386/cpu.c b/target/i386/cpu.c index d70954b..e2974ad 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -358,6 +358,20 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EAX, .tcg_features = TCG_KVM_FEATURES, }, + [FEAT_KVM_HINTS] = { + .feat_names = { + "hint-dedicated", NULL, NULL, NULL, + NULL, NULL, NULL, NULL, + NULL, NULL, NULL, NULL, + NULL, NULL, NULL, NULL, + NULL, NULL, NULL, NULL, + NULL, NULL, NULL, NULL, + NULL, NULL, NULL, NULL, + NULL, NULL, NULL, NULL, + }, + .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EDX, + .tcg_features = TCG_KVM_FEATURES, + }, [FEAT_HYPERV_EAX] = { .feat_names = { NULL /* hv_msr_vp_runtime_access */, NULL /* hv_msr_time_refcount_access */, diff --git a/target/i386/cpu.h b/target/i386/cpu.h index f91e37d..9f73692 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -475,6 +475,7 @@ typedef enum FeatureWord { FEAT_8000_0008_EBX, /* CPUID[8000_0008].EBX */ FEAT_C000_0001_EDX, /* CPUID[C000_0001].EDX */ FEAT_KVM, /* CPUID[4000_0001].EAX (KVM_CPUID_FEATURES) */ + FEAT_KVM_HINTS, /* CPUID[4000_0001].EDX */ FEAT_HYPERV_EAX, /* CPUID[4000_0003].EAX */ FEAT_HYPERV_EBX, /* CPUID[4000_0003].EBX */ FEAT_HYPERV_EDX, /* CPUID[4000_0003].EDX */ @@ -670,6 +671,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; #define CPUID_7_0_EDX_AVX512_4FMAPS (1U << 3) /* AVX512 Multiply Accumulation Single Precision */ #define CPUID_7_0_EDX_SPEC_CTRL (1U << 26) /* Speculation Control */ +#define KVM_HINTS_DEDICATED (1U << 0) + #define CPUID_8000_0008_EBX_IBPB (1U << 12) /* Indirect Branch Prediction Barrier */ #define CPUID_XSAVE_XSAVEOPT (1U << 0) diff --git a/target/i386/kvm.c b/target/i386/kvm.c index ad4b159..a0aad80 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -383,6 +383,9 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function, if (!kvm_irqchip_in_kernel()) { ret &= ~(1U << KVM_FEATURE_PV_UNHALT); } + } else if (function == KVM_CPUID_FEATURES && reg == R_EDX) { + ret |= KVM_HINTS_DEDICATED; + found = 1; } /* fallback for older kernels */ Regards, Wanpeng Li ^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-09 12:24 ` Wanpeng Li @ 2018-02-09 12:46 ` Paolo Bonzini 2018-02-09 12:46 ` Eduardo Habkost 1 sibling, 0 replies; 11+ messages in thread From: Paolo Bonzini @ 2018-02-09 12:46 UTC (permalink / raw) To: Wanpeng Li, Eduardo Habkost Cc: qemu-devel@nongnu.org Developers, kvm, Radim Krčmář On 09/02/2018 13:24, Wanpeng Li wrote: > The guest fails to detect the new cpuid this time. You have to debug the KVM_SET_CPUID2 ioctls and see why it is not set. Paolo > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index d70954b..e2974ad 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -358,6 +358,20 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { > .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EAX, > .tcg_features = TCG_KVM_FEATURES, > }, > + [FEAT_KVM_HINTS] = { > + .feat_names = { > + "hint-dedicated", NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + }, > + .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EDX, > + .tcg_features = TCG_KVM_FEATURES, > + }, ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-09 12:24 ` Wanpeng Li 2018-02-09 12:46 ` Paolo Bonzini @ 2018-02-09 12:46 ` Eduardo Habkost 2018-02-09 14:26 ` Wanpeng Li 1 sibling, 1 reply; 11+ messages in thread From: Eduardo Habkost @ 2018-02-09 12:46 UTC (permalink / raw) To: Wanpeng Li Cc: Paolo Bonzini, qemu-devel@nongnu.org Developers, kvm, Radim Krčmář On Fri, Feb 09, 2018 at 08:24:26PM +0800, Wanpeng Li wrote: > 2018-02-09 19:46 GMT+08:00 Eduardo Habkost <ehabkost@redhat.com>: > > On Fri, Feb 09, 2018 at 09:41:41AM +0100, Paolo Bonzini wrote: > >> On 08/02/2018 19:12, Eduardo Habkost wrote: > >> > On Thu, Feb 08, 2018 at 05:44:20PM +0800, Wanpeng Li wrote: > >> >> From: Wanpeng Li <wanpengli@tencent.com> > >> >> > >> >> Add PV_DEDICATED hint cpuid feature bit. > >> >> > >> > [...] > >> >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c > >> >> index d70954b..cf48931 100644 > >> >> --- a/target/i386/cpu.c > >> >> +++ b/target/i386/cpu.c > >> >> @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) > >> >> x86_cpu_get_supported_feature_word(w, false); > >> >> uint32_t requested_features = env->features[w]; > >> >> env->features[w] &= host_feat; > >> >> + if (cpu->pv_dedicated && (w == FEAT_KVM)) { > >> >> + env->features[w] |= CPUID_PV_DEDICATED; > >> >> + } > >> > > >> > Why do this trick here instead of just adding "pv-dedicated" to > >> > feature_word_info[FEAT_KVM].feat_names? > >> > >> I think because it can be added independent of KVM_GET_SUPPORTED_CPUID. > > > > If QEMU knows it can be enabled if outside GET_SUPPORTED_CPUID, > > kvm_arch_get_supported_cpuid() can return it as supported. > > The guest fails to detect the new cpuid this time. This should fix it: diff --git a/target/i386/kvm.c b/target/i386/kvm.c index a0aad808bd..44ee524188 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -804,6 +804,7 @@ int kvm_arch_init_vcpu(CPUState *cs) c = &cpuid_data.entries[cpuid_i++]; c->function = KVM_CPUID_FEATURES | kvm_base; c->eax = env->features[FEAT_KVM]; + c->edx = env->features[FEAT_KVM_HINTS]; } cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused); > > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index d70954b..e2974ad 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -358,6 +358,20 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { > .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EAX, > .tcg_features = TCG_KVM_FEATURES, > }, > + [FEAT_KVM_HINTS] = { > + .feat_names = { > + "hint-dedicated", NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + NULL, NULL, NULL, NULL, > + }, > + .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EDX, > + .tcg_features = TCG_KVM_FEATURES, > + }, > [FEAT_HYPERV_EAX] = { > .feat_names = { > NULL /* hv_msr_vp_runtime_access */, NULL /* > hv_msr_time_refcount_access */, > diff --git a/target/i386/cpu.h b/target/i386/cpu.h > index f91e37d..9f73692 100644 > --- a/target/i386/cpu.h > +++ b/target/i386/cpu.h > @@ -475,6 +475,7 @@ typedef enum FeatureWord { > FEAT_8000_0008_EBX, /* CPUID[8000_0008].EBX */ > FEAT_C000_0001_EDX, /* CPUID[C000_0001].EDX */ > FEAT_KVM, /* CPUID[4000_0001].EAX (KVM_CPUID_FEATURES) */ > + FEAT_KVM_HINTS, /* CPUID[4000_0001].EDX */ > FEAT_HYPERV_EAX, /* CPUID[4000_0003].EAX */ > FEAT_HYPERV_EBX, /* CPUID[4000_0003].EBX */ > FEAT_HYPERV_EDX, /* CPUID[4000_0003].EDX */ > @@ -670,6 +671,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; > #define CPUID_7_0_EDX_AVX512_4FMAPS (1U << 3) /* AVX512 Multiply > Accumulation Single Precision */ > #define CPUID_7_0_EDX_SPEC_CTRL (1U << 26) /* Speculation Control */ > > +#define KVM_HINTS_DEDICATED (1U << 0) > + > #define CPUID_8000_0008_EBX_IBPB (1U << 12) /* Indirect Branch > Prediction Barrier */ > > #define CPUID_XSAVE_XSAVEOPT (1U << 0) > diff --git a/target/i386/kvm.c b/target/i386/kvm.c > index ad4b159..a0aad80 100644 > --- a/target/i386/kvm.c > +++ b/target/i386/kvm.c > @@ -383,6 +383,9 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, > uint32_t function, > if (!kvm_irqchip_in_kernel()) { > ret &= ~(1U << KVM_FEATURE_PV_UNHALT); > } > + } else if (function == KVM_CPUID_FEATURES && reg == R_EDX) { > + ret |= KVM_HINTS_DEDICATED; > + found = 1; > } > > /* fallback for older kernels */ > > > Regards, > Wanpeng Li -- Eduardo ^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-09 12:46 ` Eduardo Habkost @ 2018-02-09 14:26 ` Wanpeng Li 0 siblings, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2018-02-09 14:26 UTC (permalink / raw) To: Eduardo Habkost Cc: Paolo Bonzini, qemu-devel@nongnu.org Developers, kvm, Radim Krčmář 2018-02-09 20:46 GMT+08:00 Eduardo Habkost <ehabkost@redhat.com>: > On Fri, Feb 09, 2018 at 08:24:26PM +0800, Wanpeng Li wrote: >> 2018-02-09 19:46 GMT+08:00 Eduardo Habkost <ehabkost@redhat.com>: >> > On Fri, Feb 09, 2018 at 09:41:41AM +0100, Paolo Bonzini wrote: >> >> On 08/02/2018 19:12, Eduardo Habkost wrote: >> >> > On Thu, Feb 08, 2018 at 05:44:20PM +0800, Wanpeng Li wrote: >> >> >> From: Wanpeng Li <wanpengli@tencent.com> >> >> >> >> >> >> Add PV_DEDICATED hint cpuid feature bit. >> >> >> >> >> > [...] >> >> >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> >> >> index d70954b..cf48931 100644 >> >> >> --- a/target/i386/cpu.c >> >> >> +++ b/target/i386/cpu.c >> >> >> @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) >> >> >> x86_cpu_get_supported_feature_word(w, false); >> >> >> uint32_t requested_features = env->features[w]; >> >> >> env->features[w] &= host_feat; >> >> >> + if (cpu->pv_dedicated && (w == FEAT_KVM)) { >> >> >> + env->features[w] |= CPUID_PV_DEDICATED; >> >> >> + } >> >> > >> >> > Why do this trick here instead of just adding "pv-dedicated" to >> >> > feature_word_info[FEAT_KVM].feat_names? >> >> >> >> I think because it can be added independent of KVM_GET_SUPPORTED_CPUID. >> > >> > If QEMU knows it can be enabled if outside GET_SUPPORTED_CPUID, >> > kvm_arch_get_supported_cpuid() can return it as supported. >> >> The guest fails to detect the new cpuid this time. > > This should fix it: > > diff --git a/target/i386/kvm.c b/target/i386/kvm.c > index a0aad808bd..44ee524188 100644 > --- a/target/i386/kvm.c > +++ b/target/i386/kvm.c > @@ -804,6 +804,7 @@ int kvm_arch_init_vcpu(CPUState *cs) > c = &cpuid_data.entries[cpuid_i++]; > c->function = KVM_CPUID_FEATURES | kvm_base; > c->eax = env->features[FEAT_KVM]; > + c->edx = env->features[FEAT_KVM_HINTS]; > } > > cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused); > Yeah, thanks, fold this in v2. Regards, Wanpeng Li >> >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> index d70954b..e2974ad 100644 >> --- a/target/i386/cpu.c >> +++ b/target/i386/cpu.c >> @@ -358,6 +358,20 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = { >> .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EAX, >> .tcg_features = TCG_KVM_FEATURES, >> }, >> + [FEAT_KVM_HINTS] = { >> + .feat_names = { >> + "hint-dedicated", NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + NULL, NULL, NULL, NULL, >> + }, >> + .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EDX, >> + .tcg_features = TCG_KVM_FEATURES, >> + }, >> [FEAT_HYPERV_EAX] = { >> .feat_names = { >> NULL /* hv_msr_vp_runtime_access */, NULL /* >> hv_msr_time_refcount_access */, >> diff --git a/target/i386/cpu.h b/target/i386/cpu.h >> index f91e37d..9f73692 100644 >> --- a/target/i386/cpu.h >> +++ b/target/i386/cpu.h >> @@ -475,6 +475,7 @@ typedef enum FeatureWord { >> FEAT_8000_0008_EBX, /* CPUID[8000_0008].EBX */ >> FEAT_C000_0001_EDX, /* CPUID[C000_0001].EDX */ >> FEAT_KVM, /* CPUID[4000_0001].EAX (KVM_CPUID_FEATURES) */ >> + FEAT_KVM_HINTS, /* CPUID[4000_0001].EDX */ >> FEAT_HYPERV_EAX, /* CPUID[4000_0003].EAX */ >> FEAT_HYPERV_EBX, /* CPUID[4000_0003].EBX */ >> FEAT_HYPERV_EDX, /* CPUID[4000_0003].EDX */ >> @@ -670,6 +671,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; >> #define CPUID_7_0_EDX_AVX512_4FMAPS (1U << 3) /* AVX512 Multiply >> Accumulation Single Precision */ >> #define CPUID_7_0_EDX_SPEC_CTRL (1U << 26) /* Speculation Control */ >> >> +#define KVM_HINTS_DEDICATED (1U << 0) >> + >> #define CPUID_8000_0008_EBX_IBPB (1U << 12) /* Indirect Branch >> Prediction Barrier */ >> >> #define CPUID_XSAVE_XSAVEOPT (1U << 0) >> diff --git a/target/i386/kvm.c b/target/i386/kvm.c >> index ad4b159..a0aad80 100644 >> --- a/target/i386/kvm.c >> +++ b/target/i386/kvm.c >> @@ -383,6 +383,9 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, >> uint32_t function, >> if (!kvm_irqchip_in_kernel()) { >> ret &= ~(1U << KVM_FEATURE_PV_UNHALT); >> } >> + } else if (function == KVM_CPUID_FEATURES && reg == R_EDX) { >> + ret |= KVM_HINTS_DEDICATED; >> + found = 1; >> } >> >> /* fallback for older kernels */ >> >> >> Regards, >> Wanpeng Li > > -- > Eduardo ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-08 9:44 [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit Wanpeng Li 2018-02-08 18:12 ` Eduardo Habkost @ 2018-02-09 8:41 ` Paolo Bonzini 2018-02-09 14:27 ` Wanpeng Li 1 sibling, 1 reply; 11+ messages in thread From: Paolo Bonzini @ 2018-02-09 8:41 UTC (permalink / raw) To: Wanpeng Li, qemu-devel, kvm; +Cc: Radim Krčmář, Eduardo Habkost On 08/02/2018 10:44, Wanpeng Li wrote: > From: Wanpeng Li <wanpengli@tencent.com> > > Add PV_DEDICATED hint cpuid feature bit. Please add a new feature word, since this is not a PV feature but more like a performance hint. Thanks, Paolo > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: Radim Krčmář <rkrcmar@redhat.com> > Cc: Eduardo Habkost <ehabkost@redhat.com> > Signed-off-by: Wanpeng Li <wanpengli@tencent.com> > --- > target/i386/cpu.c | 4 ++++ > target/i386/cpu.h | 3 +++ > 2 files changed, 7 insertions(+) > > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index d70954b..cf48931 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) > x86_cpu_get_supported_feature_word(w, false); > uint32_t requested_features = env->features[w]; > env->features[w] &= host_feat; > + if (cpu->pv_dedicated && (w == FEAT_KVM)) { > + env->features[w] |= CPUID_PV_DEDICATED; > + } > cpu->filtered_features[w] = requested_features & ~env->features[w]; > if (cpu->filtered_features[w]) { > rv = 1; > @@ -4682,6 +4685,7 @@ static Property x86_cpu_properties[] = { > false), > DEFINE_PROP_BOOL("vmware-cpuid-freq", X86CPU, vmware_cpuid_freq, true), > DEFINE_PROP_BOOL("tcg-cpuid", X86CPU, expose_tcg, true), > + DEFINE_PROP_BOOL("pv-dedicated", X86CPU, pv_dedicated, false), > > /* > * From "Requirements for Implementing the Microsoft > diff --git a/target/i386/cpu.h b/target/i386/cpu.h > index f91e37d..8000da5 100644 > --- a/target/i386/cpu.h > +++ b/target/i386/cpu.h > @@ -672,6 +672,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; > > #define CPUID_8000_0008_EBX_IBPB (1U << 12) /* Indirect Branch Prediction Barrier */ > > +#define CPUID_PV_DEDICATED (1U << 8) > + > #define CPUID_XSAVE_XSAVEOPT (1U << 0) > #define CPUID_XSAVE_XSAVEC (1U << 1) > #define CPUID_XSAVE_XGETBV1 (1U << 2) > @@ -1276,6 +1278,7 @@ struct X86CPU { > bool expose_kvm; > bool expose_tcg; > bool migratable; > + bool pv_dedicated; > bool max_features; /* Enable all supported features automatically */ > uint32_t apic_id; > > ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit 2018-02-09 8:41 ` Paolo Bonzini @ 2018-02-09 14:27 ` Wanpeng Li 0 siblings, 0 replies; 11+ messages in thread From: Wanpeng Li @ 2018-02-09 14:27 UTC (permalink / raw) To: Paolo Bonzini Cc: qemu-devel@nongnu.org Developers, kvm, Radim Krčmář, Eduardo Habkost 2018-02-09 16:41 GMT+08:00 Paolo Bonzini <bonzini@gnu.org>: > On 08/02/2018 10:44, Wanpeng Li wrote: >> From: Wanpeng Li <wanpengli@tencent.com> >> >> Add PV_DEDICATED hint cpuid feature bit. > > Please add a new feature word, since this is not a PV feature but more > like a performance hint. Do it in v2. Regards, Wanpeng Li > > Thanks, > > Paolo > >> Cc: Paolo Bonzini <pbonzini@redhat.com> >> Cc: Radim Krčmář <rkrcmar@redhat.com> >> Cc: Eduardo Habkost <ehabkost@redhat.com> >> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> >> --- >> target/i386/cpu.c | 4 ++++ >> target/i386/cpu.h | 3 +++ >> 2 files changed, 7 insertions(+) >> >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> index d70954b..cf48931 100644 >> --- a/target/i386/cpu.c >> +++ b/target/i386/cpu.c >> @@ -4076,6 +4076,9 @@ static int x86_cpu_filter_features(X86CPU *cpu) >> x86_cpu_get_supported_feature_word(w, false); >> uint32_t requested_features = env->features[w]; >> env->features[w] &= host_feat; >> + if (cpu->pv_dedicated && (w == FEAT_KVM)) { >> + env->features[w] |= CPUID_PV_DEDICATED; >> + } >> cpu->filtered_features[w] = requested_features & ~env->features[w]; >> if (cpu->filtered_features[w]) { >> rv = 1; >> @@ -4682,6 +4685,7 @@ static Property x86_cpu_properties[] = { >> false), >> DEFINE_PROP_BOOL("vmware-cpuid-freq", X86CPU, vmware_cpuid_freq, true), >> DEFINE_PROP_BOOL("tcg-cpuid", X86CPU, expose_tcg, true), >> + DEFINE_PROP_BOOL("pv-dedicated", X86CPU, pv_dedicated, false), >> >> /* >> * From "Requirements for Implementing the Microsoft >> diff --git a/target/i386/cpu.h b/target/i386/cpu.h >> index f91e37d..8000da5 100644 >> --- a/target/i386/cpu.h >> +++ b/target/i386/cpu.h >> @@ -672,6 +672,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS]; >> >> #define CPUID_8000_0008_EBX_IBPB (1U << 12) /* Indirect Branch Prediction Barrier */ >> >> +#define CPUID_PV_DEDICATED (1U << 8) >> + >> #define CPUID_XSAVE_XSAVEOPT (1U << 0) >> #define CPUID_XSAVE_XSAVEC (1U << 1) >> #define CPUID_XSAVE_XGETBV1 (1U << 2) >> @@ -1276,6 +1278,7 @@ struct X86CPU { >> bool expose_kvm; >> bool expose_tcg; >> bool migratable; >> + bool pv_dedicated; >> bool max_features; /* Enable all supported features automatically */ >> uint32_t apic_id; >> >> > ^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2018-02-09 14:27 UTC | newest] Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2018-02-08 9:44 [Qemu-devel] [PATCH] target-i386: adds PV_DEDICATED hint CPUID feature bit Wanpeng Li 2018-02-08 18:12 ` Eduardo Habkost 2018-02-09 3:18 ` Wanpeng Li 2018-02-09 8:41 ` Paolo Bonzini 2018-02-09 11:46 ` Eduardo Habkost 2018-02-09 12:24 ` Wanpeng Li 2018-02-09 12:46 ` Paolo Bonzini 2018-02-09 12:46 ` Eduardo Habkost 2018-02-09 14:26 ` Wanpeng Li 2018-02-09 8:41 ` Paolo Bonzini 2018-02-09 14:27 ` Wanpeng Li
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