| Message ID | 20240524073812.731032-2-maobibo@loongson.cn (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | LoongArch: Add steal time support | expand |
Hi, Bibo, On Fri, May 24, 2024 at 3:38 PM Bibo Mao <maobibo@loongson.cn> wrote: > > Steal time feature is added here in kvm side, VM can search supported > features provided by KVM hypervisor, feature KVM_FEATURE_STEAL_TIME > is added here. Like x86, steal time structure is saved in guest memory, > one hypercall function KVM_HCALL_FUNC_NOTIFY is added to notify KVM to > enable the feature. > > One cpu attr ioctl command KVM_LOONGARCH_VCPU_PVTIME_CTRL is added to > save and restore base address of steal time structure when VM is migrated. > > Signed-off-by: Bibo Mao <maobibo@loongson.cn> > --- > arch/loongarch/include/asm/kvm_host.h | 7 ++ > arch/loongarch/include/asm/kvm_para.h | 10 ++ > arch/loongarch/include/asm/kvm_vcpu.h | 4 + > arch/loongarch/include/asm/loongarch.h | 1 + > arch/loongarch/include/uapi/asm/kvm.h | 4 + > arch/loongarch/kvm/Kconfig | 1 + > arch/loongarch/kvm/exit.c | 38 +++++++- > arch/loongarch/kvm/vcpu.c | 124 +++++++++++++++++++++++++ > 8 files changed, 187 insertions(+), 2 deletions(-) > > diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h > index c87b6ea0ec47..2eb2f7572023 100644 > --- a/arch/loongarch/include/asm/kvm_host.h > +++ b/arch/loongarch/include/asm/kvm_host.h > @@ -30,6 +30,7 @@ > #define KVM_PRIVATE_MEM_SLOTS 0 > > #define KVM_HALT_POLL_NS_DEFAULT 500000 > +#define KVM_REQ_STEAL_UPDATE KVM_ARCH_REQ(1) > > #define KVM_GUESTDBG_SW_BP_MASK \ > (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) > @@ -201,6 +202,12 @@ struct kvm_vcpu_arch { > struct kvm_mp_state mp_state; > /* cpucfg */ > u32 cpucfg[KVM_MAX_CPUCFG_REGS]; > + /* paravirt steal time */ > + struct { > + u64 guest_addr; > + u64 last_steal; > + struct gfn_to_hva_cache cache; > + } st; > }; > > static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg) > diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h > index 4ba2312e5f8c..a9ba8185d4af 100644 > --- a/arch/loongarch/include/asm/kvm_para.h > +++ b/arch/loongarch/include/asm/kvm_para.h > @@ -14,6 +14,7 @@ > > #define KVM_HCALL_SERVICE HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SERVICE) > #define KVM_HCALL_FUNC_IPI 1 > +#define KVM_HCALL_FUNC_NOTIFY 2 > > #define KVM_HCALL_SWDBG HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SWDBG) > > @@ -24,6 +25,15 @@ > #define KVM_HCALL_INVALID_CODE -1UL > #define KVM_HCALL_INVALID_PARAMETER -2UL > > +#define KVM_STEAL_PHYS_VALID BIT_ULL(0) > +#define KVM_STEAL_PHYS_MASK GENMASK_ULL(63, 6) > +struct kvm_steal_time { > + __u64 steal; > + __u32 version; > + __u32 flags; I found that x86 has a preempted field here, in our internal repo the LoongArch version also has this field. Moreover, kvm_steal_time_set_preempted() and kvm_steal_time_clear_preempted() seems needed. > + __u32 pad[12]; > +}; > + > /* > * Hypercall interface for KVM hypervisor > * > diff --git a/arch/loongarch/include/asm/kvm_vcpu.h b/arch/loongarch/include/asm/kvm_vcpu.h > index 590a92cb5416..d7e51300a89f 100644 > --- a/arch/loongarch/include/asm/kvm_vcpu.h > +++ b/arch/loongarch/include/asm/kvm_vcpu.h > @@ -120,4 +120,8 @@ static inline void kvm_write_reg(struct kvm_vcpu *vcpu, int num, unsigned long v > vcpu->arch.gprs[num] = val; > } > > +static inline bool kvm_pvtime_supported(void) > +{ > + return !!sched_info_on(); > +} > #endif /* __ASM_LOONGARCH_KVM_VCPU_H__ */ > diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h > index eb09adda54b7..7a4633ef284b 100644 > --- a/arch/loongarch/include/asm/loongarch.h > +++ b/arch/loongarch/include/asm/loongarch.h > @@ -169,6 +169,7 @@ > #define KVM_SIGNATURE "KVM\0" > #define CPUCFG_KVM_FEATURE (CPUCFG_KVM_BASE + 4) > #define KVM_FEATURE_IPI BIT(1) > +#define KVM_FEATURE_STEAL_TIME BIT(2) > > #ifndef __ASSEMBLY__ > > diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h > index f9abef382317..ddc5cab0ffd0 100644 > --- a/arch/loongarch/include/uapi/asm/kvm.h > +++ b/arch/loongarch/include/uapi/asm/kvm.h > @@ -81,7 +81,11 @@ struct kvm_fpu { > #define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT)) > #define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG) > #define KVM_IOC_CPUCFG(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CPUCFG, REG) > + > +/* Device Control API on vcpu fd */ > #define KVM_LOONGARCH_VCPU_CPUCFG 0 > +#define KVM_LOONGARCH_VCPU_PVTIME_CTRL 1 > +#define KVM_LOONGARCH_VCPU_PVTIME_GPA 0 > > struct kvm_debug_exit_arch { > }; > diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig > index c4ef2b4d9797..248744b4d086 100644 > --- a/arch/loongarch/kvm/Kconfig > +++ b/arch/loongarch/kvm/Kconfig > @@ -29,6 +29,7 @@ config KVM > select KVM_MMIO > select HAVE_KVM_READONLY_MEM > select KVM_XFER_TO_GUEST_WORK > + select SCHED_INFO > help > Support hosting virtualized guest machines using > hardware virtualization extensions. You will need > diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c > index c86e099af5ca..e2abd97fb13f 100644 > --- a/arch/loongarch/kvm/exit.c > +++ b/arch/loongarch/kvm/exit.c > @@ -24,7 +24,7 @@ > static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) > { > int rd, rj; > - unsigned int index; > + unsigned int index, ret; > > if (inst.reg2_format.opcode != cpucfg_op) > return EMULATE_FAIL; > @@ -50,7 +50,10 @@ static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) > vcpu->arch.gprs[rd] = *(unsigned int *)KVM_SIGNATURE; > break; > case CPUCFG_KVM_FEATURE: > - vcpu->arch.gprs[rd] = KVM_FEATURE_IPI; > + ret = KVM_FEATURE_IPI; > + if (sched_info_on()) What about replacing it with your helper function kvm_pvtime_supported()? Huacai > + ret |= KVM_FEATURE_STEAL_TIME; > + vcpu->arch.gprs[rd] = ret; > break; > default: > vcpu->arch.gprs[rd] = 0; > @@ -687,6 +690,34 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu) > return RESUME_GUEST; > } > > +static long kvm_save_notify(struct kvm_vcpu *vcpu) > +{ > + unsigned long id, data; > + > + id = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); > + data = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); > + switch (id) { > + case KVM_FEATURE_STEAL_TIME: > + if (!kvm_pvtime_supported()) > + return KVM_HCALL_INVALID_CODE; > + > + if (data & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) > + return KVM_HCALL_INVALID_PARAMETER; > + > + vcpu->arch.st.guest_addr = data; > + if (!(data & KVM_STEAL_PHYS_VALID)) > + break; > + > + vcpu->arch.st.last_steal = current->sched_info.run_delay; > + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > + break; > + default: > + break; > + }; > + > + return 0; > +}; > + > /* > * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root. > * @vcpu: Virtual CPU context. > @@ -758,6 +789,9 @@ static void kvm_handle_service(struct kvm_vcpu *vcpu) > kvm_send_pv_ipi(vcpu); > ret = KVM_HCALL_SUCCESS; > break; > + case KVM_HCALL_FUNC_NOTIFY: > + ret = kvm_save_notify(vcpu); > + break; > default: > ret = KVM_HCALL_INVALID_CODE; > break; > diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c > index 9e8030d45129..382796f1d3e6 100644 > --- a/arch/loongarch/kvm/vcpu.c > +++ b/arch/loongarch/kvm/vcpu.c > @@ -31,6 +31,117 @@ const struct kvm_stats_header kvm_vcpu_stats_header = { > sizeof(kvm_vcpu_stats_desc), > }; > > +static void kvm_update_stolen_time(struct kvm_vcpu *vcpu) > +{ > + struct kvm_steal_time __user *st; > + struct gfn_to_hva_cache *ghc; > + struct kvm_memslots *slots; > + gpa_t gpa; > + u64 steal; > + u32 version; > + > + ghc = &vcpu->arch.st.cache; > + gpa = vcpu->arch.st.guest_addr; > + if (!(gpa & KVM_STEAL_PHYS_VALID)) > + return; > + > + gpa &= KVM_STEAL_PHYS_MASK; > + slots = kvm_memslots(vcpu->kvm); > + if (slots->generation != ghc->generation || gpa != ghc->gpa) { > + if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, > + sizeof(*st))) { > + ghc->gpa = INVALID_GPA; > + return; > + } > + } > + > + st = (struct kvm_steal_time __user *)ghc->hva; > + unsafe_get_user(version, &st->version, out); > + if (version & 1) > + version += 1; > + version += 1; > + unsafe_put_user(version, &st->version, out); > + smp_wmb(); > + > + unsafe_get_user(steal, &st->steal, out); > + steal += current->sched_info.run_delay - > + vcpu->arch.st.last_steal; > + vcpu->arch.st.last_steal = current->sched_info.run_delay; > + unsafe_put_user(steal, &st->steal, out); > + > + smp_wmb(); > + version += 1; > + unsafe_put_user(version, &st->version, out); > +out: > + mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); > +} > + > +static int kvm_loongarch_pvtime_has_attr(struct kvm_vcpu *vcpu, > + struct kvm_device_attr *attr) > +{ > + if (!kvm_pvtime_supported() || > + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > + return -ENXIO; > + > + return 0; > +} > + > +static int kvm_loongarch_pvtime_get_attr(struct kvm_vcpu *vcpu, > + struct kvm_device_attr *attr) > +{ > + u64 __user *user = (u64 __user *)attr->addr; > + u64 gpa; > + > + if (!kvm_pvtime_supported() || > + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > + return -ENXIO; > + > + gpa = vcpu->arch.st.guest_addr; > + if (put_user(gpa, user)) > + return -EFAULT; > + > + return 0; > +} > + > +static int kvm_loongarch_pvtime_set_attr(struct kvm_vcpu *vcpu, > + struct kvm_device_attr *attr) > +{ > + u64 __user *user = (u64 __user *)attr->addr; > + struct kvm *kvm = vcpu->kvm; > + u64 gpa; > + int ret = 0; > + int idx; > + > + if (!kvm_pvtime_supported() || > + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > + return -ENXIO; > + > + if (get_user(gpa, user)) > + return -EFAULT; > + > + if (gpa & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) > + return -EINVAL; > + > + if (!(gpa & KVM_STEAL_PHYS_VALID)) { > + vcpu->arch.st.guest_addr = gpa; > + return 0; > + } > + > + /* Check the address is in a valid memslot */ > + idx = srcu_read_lock(&kvm->srcu); > + if (kvm_is_error_hva(gfn_to_hva(kvm, gpa >> PAGE_SHIFT))) > + ret = -EINVAL; > + srcu_read_unlock(&kvm->srcu, idx); > + > + if (!ret) { > + vcpu->arch.st.guest_addr = gpa; > + vcpu->arch.st.last_steal = current->sched_info.run_delay; > + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > + } > + > + return ret; > +} > + > /* > * kvm_check_requests - check and handle pending vCPU requests > * > @@ -48,6 +159,9 @@ static int kvm_check_requests(struct kvm_vcpu *vcpu) > if (kvm_dirty_ring_check_request(vcpu)) > return RESUME_HOST; > > + if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) > + kvm_update_stolen_time(vcpu); > + > return RESUME_GUEST; > } > > @@ -671,6 +785,9 @@ static int kvm_loongarch_vcpu_has_attr(struct kvm_vcpu *vcpu, > case KVM_LOONGARCH_VCPU_CPUCFG: > ret = kvm_loongarch_cpucfg_has_attr(vcpu, attr); > break; > + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > + ret = kvm_loongarch_pvtime_has_attr(vcpu, attr); > + break; > default: > break; > } > @@ -703,6 +820,9 @@ static int kvm_loongarch_vcpu_get_attr(struct kvm_vcpu *vcpu, > case KVM_LOONGARCH_VCPU_CPUCFG: > ret = kvm_loongarch_get_cpucfg_attr(vcpu, attr); > break; > + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > + ret = kvm_loongarch_pvtime_get_attr(vcpu, attr); > + break; > default: > break; > } > @@ -725,6 +845,9 @@ static int kvm_loongarch_vcpu_set_attr(struct kvm_vcpu *vcpu, > case KVM_LOONGARCH_VCPU_CPUCFG: > ret = kvm_loongarch_cpucfg_set_attr(vcpu, attr); > break; > + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > + ret = kvm_loongarch_pvtime_set_attr(vcpu, attr); > + break; > default: > break; > } > @@ -1084,6 +1207,7 @@ static int _kvm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) > > /* Control guest page CCA attribute */ > change_csr_gcfg(CSR_GCFG_MATC_MASK, CSR_GCFG_MATC_ROOT); > + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > > /* Don't bother restoring registers multiple times unless necessary */ > if (vcpu->arch.aux_inuse & KVM_LARCH_HWCSR_USABLE) > -- > 2.39.3 >
Huacai, On 2024/7/6 上午11:00, Huacai Chen wrote: > Hi, Bibo, > > On Fri, May 24, 2024 at 3:38 PM Bibo Mao <maobibo@loongson.cn> wrote: >> >> Steal time feature is added here in kvm side, VM can search supported >> features provided by KVM hypervisor, feature KVM_FEATURE_STEAL_TIME >> is added here. Like x86, steal time structure is saved in guest memory, >> one hypercall function KVM_HCALL_FUNC_NOTIFY is added to notify KVM to >> enable the feature. >> >> One cpu attr ioctl command KVM_LOONGARCH_VCPU_PVTIME_CTRL is added to >> save and restore base address of steal time structure when VM is migrated. >> >> Signed-off-by: Bibo Mao <maobibo@loongson.cn> >> --- >> arch/loongarch/include/asm/kvm_host.h | 7 ++ >> arch/loongarch/include/asm/kvm_para.h | 10 ++ >> arch/loongarch/include/asm/kvm_vcpu.h | 4 + >> arch/loongarch/include/asm/loongarch.h | 1 + >> arch/loongarch/include/uapi/asm/kvm.h | 4 + >> arch/loongarch/kvm/Kconfig | 1 + >> arch/loongarch/kvm/exit.c | 38 +++++++- >> arch/loongarch/kvm/vcpu.c | 124 +++++++++++++++++++++++++ >> 8 files changed, 187 insertions(+), 2 deletions(-) >> >> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h >> index c87b6ea0ec47..2eb2f7572023 100644 >> --- a/arch/loongarch/include/asm/kvm_host.h >> +++ b/arch/loongarch/include/asm/kvm_host.h >> @@ -30,6 +30,7 @@ >> #define KVM_PRIVATE_MEM_SLOTS 0 >> >> #define KVM_HALT_POLL_NS_DEFAULT 500000 >> +#define KVM_REQ_STEAL_UPDATE KVM_ARCH_REQ(1) >> >> #define KVM_GUESTDBG_SW_BP_MASK \ >> (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) >> @@ -201,6 +202,12 @@ struct kvm_vcpu_arch { >> struct kvm_mp_state mp_state; >> /* cpucfg */ >> u32 cpucfg[KVM_MAX_CPUCFG_REGS]; >> + /* paravirt steal time */ >> + struct { >> + u64 guest_addr; >> + u64 last_steal; >> + struct gfn_to_hva_cache cache; >> + } st; >> }; >> >> static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg) >> diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h >> index 4ba2312e5f8c..a9ba8185d4af 100644 >> --- a/arch/loongarch/include/asm/kvm_para.h >> +++ b/arch/loongarch/include/asm/kvm_para.h >> @@ -14,6 +14,7 @@ >> >> #define KVM_HCALL_SERVICE HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SERVICE) >> #define KVM_HCALL_FUNC_IPI 1 >> +#define KVM_HCALL_FUNC_NOTIFY 2 >> >> #define KVM_HCALL_SWDBG HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SWDBG) >> >> @@ -24,6 +25,15 @@ >> #define KVM_HCALL_INVALID_CODE -1UL >> #define KVM_HCALL_INVALID_PARAMETER -2UL >> >> +#define KVM_STEAL_PHYS_VALID BIT_ULL(0) >> +#define KVM_STEAL_PHYS_MASK GENMASK_ULL(63, 6) >> +struct kvm_steal_time { >> + __u64 steal; >> + __u32 version; >> + __u32 flags; > I found that x86 has a preempted field here, in our internal repo the > LoongArch version also has this field. Moreover, > kvm_steal_time_set_preempted() and kvm_steal_time_clear_preempted() > seems needed. By my understanding, macro vcpu_is_preempted() is used together with pv spinlock, and pv spinlock depends on pv stealtime. So I think preempted flag is not part of pv stealtime, it is part of pv spinlock. We are going to add preempted field if pv spinlock is added. > >> + __u32 pad[12]; >> +}; >> + >> /* >> * Hypercall interface for KVM hypervisor >> * >> diff --git a/arch/loongarch/include/asm/kvm_vcpu.h b/arch/loongarch/include/asm/kvm_vcpu.h >> index 590a92cb5416..d7e51300a89f 100644 >> --- a/arch/loongarch/include/asm/kvm_vcpu.h >> +++ b/arch/loongarch/include/asm/kvm_vcpu.h >> @@ -120,4 +120,8 @@ static inline void kvm_write_reg(struct kvm_vcpu *vcpu, int num, unsigned long v >> vcpu->arch.gprs[num] = val; >> } >> >> +static inline bool kvm_pvtime_supported(void) >> +{ >> + return !!sched_info_on(); >> +} >> #endif /* __ASM_LOONGARCH_KVM_VCPU_H__ */ >> diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h >> index eb09adda54b7..7a4633ef284b 100644 >> --- a/arch/loongarch/include/asm/loongarch.h >> +++ b/arch/loongarch/include/asm/loongarch.h >> @@ -169,6 +169,7 @@ >> #define KVM_SIGNATURE "KVM\0" >> #define CPUCFG_KVM_FEATURE (CPUCFG_KVM_BASE + 4) >> #define KVM_FEATURE_IPI BIT(1) >> +#define KVM_FEATURE_STEAL_TIME BIT(2) >> >> #ifndef __ASSEMBLY__ >> >> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h >> index f9abef382317..ddc5cab0ffd0 100644 >> --- a/arch/loongarch/include/uapi/asm/kvm.h >> +++ b/arch/loongarch/include/uapi/asm/kvm.h >> @@ -81,7 +81,11 @@ struct kvm_fpu { >> #define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT)) >> #define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG) >> #define KVM_IOC_CPUCFG(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CPUCFG, REG) >> + >> +/* Device Control API on vcpu fd */ >> #define KVM_LOONGARCH_VCPU_CPUCFG 0 >> +#define KVM_LOONGARCH_VCPU_PVTIME_CTRL 1 >> +#define KVM_LOONGARCH_VCPU_PVTIME_GPA 0 >> >> struct kvm_debug_exit_arch { >> }; >> diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig >> index c4ef2b4d9797..248744b4d086 100644 >> --- a/arch/loongarch/kvm/Kconfig >> +++ b/arch/loongarch/kvm/Kconfig >> @@ -29,6 +29,7 @@ config KVM >> select KVM_MMIO >> select HAVE_KVM_READONLY_MEM >> select KVM_XFER_TO_GUEST_WORK >> + select SCHED_INFO >> help >> Support hosting virtualized guest machines using >> hardware virtualization extensions. You will need >> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c >> index c86e099af5ca..e2abd97fb13f 100644 >> --- a/arch/loongarch/kvm/exit.c >> +++ b/arch/loongarch/kvm/exit.c >> @@ -24,7 +24,7 @@ >> static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) >> { >> int rd, rj; >> - unsigned int index; >> + unsigned int index, ret; >> >> if (inst.reg2_format.opcode != cpucfg_op) >> return EMULATE_FAIL; >> @@ -50,7 +50,10 @@ static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) >> vcpu->arch.gprs[rd] = *(unsigned int *)KVM_SIGNATURE; >> break; >> case CPUCFG_KVM_FEATURE: >> - vcpu->arch.gprs[rd] = KVM_FEATURE_IPI; >> + ret = KVM_FEATURE_IPI; >> + if (sched_info_on()) > What about replacing it with your helper function kvm_pvtime_supported()? Sure, will replace it with helper function kvm_pvtime_supported(). Regards Bibo Mao > > Huacai > >> + ret |= KVM_FEATURE_STEAL_TIME; >> + vcpu->arch.gprs[rd] = ret; >> break; >> default: >> vcpu->arch.gprs[rd] = 0; >> @@ -687,6 +690,34 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu) >> return RESUME_GUEST; >> } >> >> +static long kvm_save_notify(struct kvm_vcpu *vcpu) >> +{ >> + unsigned long id, data; >> + >> + id = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); >> + data = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); >> + switch (id) { >> + case KVM_FEATURE_STEAL_TIME: >> + if (!kvm_pvtime_supported()) >> + return KVM_HCALL_INVALID_CODE; >> + >> + if (data & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) >> + return KVM_HCALL_INVALID_PARAMETER; >> + >> + vcpu->arch.st.guest_addr = data; >> + if (!(data & KVM_STEAL_PHYS_VALID)) >> + break; >> + >> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >> + break; >> + default: >> + break; >> + }; >> + >> + return 0; >> +}; >> + >> /* >> * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root. >> * @vcpu: Virtual CPU context. >> @@ -758,6 +789,9 @@ static void kvm_handle_service(struct kvm_vcpu *vcpu) >> kvm_send_pv_ipi(vcpu); >> ret = KVM_HCALL_SUCCESS; >> break; >> + case KVM_HCALL_FUNC_NOTIFY: >> + ret = kvm_save_notify(vcpu); >> + break; >> default: >> ret = KVM_HCALL_INVALID_CODE; >> break; >> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c >> index 9e8030d45129..382796f1d3e6 100644 >> --- a/arch/loongarch/kvm/vcpu.c >> +++ b/arch/loongarch/kvm/vcpu.c >> @@ -31,6 +31,117 @@ const struct kvm_stats_header kvm_vcpu_stats_header = { >> sizeof(kvm_vcpu_stats_desc), >> }; >> >> +static void kvm_update_stolen_time(struct kvm_vcpu *vcpu) >> +{ >> + struct kvm_steal_time __user *st; >> + struct gfn_to_hva_cache *ghc; >> + struct kvm_memslots *slots; >> + gpa_t gpa; >> + u64 steal; >> + u32 version; >> + >> + ghc = &vcpu->arch.st.cache; >> + gpa = vcpu->arch.st.guest_addr; >> + if (!(gpa & KVM_STEAL_PHYS_VALID)) >> + return; >> + >> + gpa &= KVM_STEAL_PHYS_MASK; >> + slots = kvm_memslots(vcpu->kvm); >> + if (slots->generation != ghc->generation || gpa != ghc->gpa) { >> + if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, >> + sizeof(*st))) { >> + ghc->gpa = INVALID_GPA; >> + return; >> + } >> + } >> + >> + st = (struct kvm_steal_time __user *)ghc->hva; >> + unsafe_get_user(version, &st->version, out); >> + if (version & 1) >> + version += 1; >> + version += 1; >> + unsafe_put_user(version, &st->version, out); >> + smp_wmb(); >> + >> + unsafe_get_user(steal, &st->steal, out); >> + steal += current->sched_info.run_delay - >> + vcpu->arch.st.last_steal; >> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >> + unsafe_put_user(steal, &st->steal, out); >> + >> + smp_wmb(); >> + version += 1; >> + unsafe_put_user(version, &st->version, out); >> +out: >> + mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); >> +} >> + >> +static int kvm_loongarch_pvtime_has_attr(struct kvm_vcpu *vcpu, >> + struct kvm_device_attr *attr) >> +{ >> + if (!kvm_pvtime_supported() || >> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >> + return -ENXIO; >> + >> + return 0; >> +} >> + >> +static int kvm_loongarch_pvtime_get_attr(struct kvm_vcpu *vcpu, >> + struct kvm_device_attr *attr) >> +{ >> + u64 __user *user = (u64 __user *)attr->addr; >> + u64 gpa; >> + >> + if (!kvm_pvtime_supported() || >> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >> + return -ENXIO; >> + >> + gpa = vcpu->arch.st.guest_addr; >> + if (put_user(gpa, user)) >> + return -EFAULT; >> + >> + return 0; >> +} >> + >> +static int kvm_loongarch_pvtime_set_attr(struct kvm_vcpu *vcpu, >> + struct kvm_device_attr *attr) >> +{ >> + u64 __user *user = (u64 __user *)attr->addr; >> + struct kvm *kvm = vcpu->kvm; >> + u64 gpa; >> + int ret = 0; >> + int idx; >> + >> + if (!kvm_pvtime_supported() || >> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >> + return -ENXIO; >> + >> + if (get_user(gpa, user)) >> + return -EFAULT; >> + >> + if (gpa & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) >> + return -EINVAL; >> + >> + if (!(gpa & KVM_STEAL_PHYS_VALID)) { >> + vcpu->arch.st.guest_addr = gpa; >> + return 0; >> + } >> + >> + /* Check the address is in a valid memslot */ >> + idx = srcu_read_lock(&kvm->srcu); >> + if (kvm_is_error_hva(gfn_to_hva(kvm, gpa >> PAGE_SHIFT))) >> + ret = -EINVAL; >> + srcu_read_unlock(&kvm->srcu, idx); >> + >> + if (!ret) { >> + vcpu->arch.st.guest_addr = gpa; >> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >> + } >> + >> + return ret; >> +} >> + >> /* >> * kvm_check_requests - check and handle pending vCPU requests >> * >> @@ -48,6 +159,9 @@ static int kvm_check_requests(struct kvm_vcpu *vcpu) >> if (kvm_dirty_ring_check_request(vcpu)) >> return RESUME_HOST; >> >> + if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) >> + kvm_update_stolen_time(vcpu); >> + >> return RESUME_GUEST; >> } >> >> @@ -671,6 +785,9 @@ static int kvm_loongarch_vcpu_has_attr(struct kvm_vcpu *vcpu, >> case KVM_LOONGARCH_VCPU_CPUCFG: >> ret = kvm_loongarch_cpucfg_has_attr(vcpu, attr); >> break; >> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >> + ret = kvm_loongarch_pvtime_has_attr(vcpu, attr); >> + break; >> default: >> break; >> } >> @@ -703,6 +820,9 @@ static int kvm_loongarch_vcpu_get_attr(struct kvm_vcpu *vcpu, >> case KVM_LOONGARCH_VCPU_CPUCFG: >> ret = kvm_loongarch_get_cpucfg_attr(vcpu, attr); >> break; >> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >> + ret = kvm_loongarch_pvtime_get_attr(vcpu, attr); >> + break; >> default: >> break; >> } >> @@ -725,6 +845,9 @@ static int kvm_loongarch_vcpu_set_attr(struct kvm_vcpu *vcpu, >> case KVM_LOONGARCH_VCPU_CPUCFG: >> ret = kvm_loongarch_cpucfg_set_attr(vcpu, attr); >> break; >> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >> + ret = kvm_loongarch_pvtime_set_attr(vcpu, attr); >> + break; >> default: >> break; >> } >> @@ -1084,6 +1207,7 @@ static int _kvm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) >> >> /* Control guest page CCA attribute */ >> change_csr_gcfg(CSR_GCFG_MATC_MASK, CSR_GCFG_MATC_ROOT); >> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >> >> /* Don't bother restoring registers multiple times unless necessary */ >> if (vcpu->arch.aux_inuse & KVM_LARCH_HWCSR_USABLE) >> -- >> 2.39.3 >>
On Sat, Jul 6, 2024 at 2:59 PM maobibo <maobibo@loongson.cn> wrote: > > Huacai, > > On 2024/7/6 上午11:00, Huacai Chen wrote: > > Hi, Bibo, > > > > On Fri, May 24, 2024 at 3:38 PM Bibo Mao <maobibo@loongson.cn> wrote: > >> > >> Steal time feature is added here in kvm side, VM can search supported > >> features provided by KVM hypervisor, feature KVM_FEATURE_STEAL_TIME > >> is added here. Like x86, steal time structure is saved in guest memory, > >> one hypercall function KVM_HCALL_FUNC_NOTIFY is added to notify KVM to > >> enable the feature. > >> > >> One cpu attr ioctl command KVM_LOONGARCH_VCPU_PVTIME_CTRL is added to > >> save and restore base address of steal time structure when VM is migrated. > >> > >> Signed-off-by: Bibo Mao <maobibo@loongson.cn> > >> --- > >> arch/loongarch/include/asm/kvm_host.h | 7 ++ > >> arch/loongarch/include/asm/kvm_para.h | 10 ++ > >> arch/loongarch/include/asm/kvm_vcpu.h | 4 + > >> arch/loongarch/include/asm/loongarch.h | 1 + > >> arch/loongarch/include/uapi/asm/kvm.h | 4 + > >> arch/loongarch/kvm/Kconfig | 1 + > >> arch/loongarch/kvm/exit.c | 38 +++++++- > >> arch/loongarch/kvm/vcpu.c | 124 +++++++++++++++++++++++++ > >> 8 files changed, 187 insertions(+), 2 deletions(-) > >> > >> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h > >> index c87b6ea0ec47..2eb2f7572023 100644 > >> --- a/arch/loongarch/include/asm/kvm_host.h > >> +++ b/arch/loongarch/include/asm/kvm_host.h > >> @@ -30,6 +30,7 @@ > >> #define KVM_PRIVATE_MEM_SLOTS 0 > >> > >> #define KVM_HALT_POLL_NS_DEFAULT 500000 > >> +#define KVM_REQ_STEAL_UPDATE KVM_ARCH_REQ(1) > >> > >> #define KVM_GUESTDBG_SW_BP_MASK \ > >> (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) > >> @@ -201,6 +202,12 @@ struct kvm_vcpu_arch { > >> struct kvm_mp_state mp_state; > >> /* cpucfg */ > >> u32 cpucfg[KVM_MAX_CPUCFG_REGS]; > >> + /* paravirt steal time */ > >> + struct { > >> + u64 guest_addr; > >> + u64 last_steal; > >> + struct gfn_to_hva_cache cache; > >> + } st; > >> }; > >> > >> static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg) > >> diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h > >> index 4ba2312e5f8c..a9ba8185d4af 100644 > >> --- a/arch/loongarch/include/asm/kvm_para.h > >> +++ b/arch/loongarch/include/asm/kvm_para.h > >> @@ -14,6 +14,7 @@ > >> > >> #define KVM_HCALL_SERVICE HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SERVICE) > >> #define KVM_HCALL_FUNC_IPI 1 > >> +#define KVM_HCALL_FUNC_NOTIFY 2 > >> > >> #define KVM_HCALL_SWDBG HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SWDBG) > >> > >> @@ -24,6 +25,15 @@ > >> #define KVM_HCALL_INVALID_CODE -1UL > >> #define KVM_HCALL_INVALID_PARAMETER -2UL > >> > >> +#define KVM_STEAL_PHYS_VALID BIT_ULL(0) > >> +#define KVM_STEAL_PHYS_MASK GENMASK_ULL(63, 6) > >> +struct kvm_steal_time { > >> + __u64 steal; > >> + __u32 version; > >> + __u32 flags; > > I found that x86 has a preempted field here, in our internal repo the > > LoongArch version also has this field. Moreover, > > kvm_steal_time_set_preempted() and kvm_steal_time_clear_preempted() > > seems needed. > By my understanding, macro vcpu_is_preempted() is used together with pv > spinlock, and pv spinlock depends on pv stealtime. So I think preempted > flag is not part of pv stealtime, it is part of pv spinlock. > > We are going to add preempted field if pv spinlock is added. > > > >> + __u32 pad[12]; > >> +}; > >> + > >> /* > >> * Hypercall interface for KVM hypervisor > >> * > >> diff --git a/arch/loongarch/include/asm/kvm_vcpu.h b/arch/loongarch/include/asm/kvm_vcpu.h > >> index 590a92cb5416..d7e51300a89f 100644 > >> --- a/arch/loongarch/include/asm/kvm_vcpu.h > >> +++ b/arch/loongarch/include/asm/kvm_vcpu.h > >> @@ -120,4 +120,8 @@ static inline void kvm_write_reg(struct kvm_vcpu *vcpu, int num, unsigned long v > >> vcpu->arch.gprs[num] = val; > >> } > >> > >> +static inline bool kvm_pvtime_supported(void) > >> +{ > >> + return !!sched_info_on(); > >> +} > >> #endif /* __ASM_LOONGARCH_KVM_VCPU_H__ */ > >> diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h > >> index eb09adda54b7..7a4633ef284b 100644 > >> --- a/arch/loongarch/include/asm/loongarch.h > >> +++ b/arch/loongarch/include/asm/loongarch.h > >> @@ -169,6 +169,7 @@ > >> #define KVM_SIGNATURE "KVM\0" > >> #define CPUCFG_KVM_FEATURE (CPUCFG_KVM_BASE + 4) > >> #define KVM_FEATURE_IPI BIT(1) > >> +#define KVM_FEATURE_STEAL_TIME BIT(2) > >> > >> #ifndef __ASSEMBLY__ > >> > >> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h > >> index f9abef382317..ddc5cab0ffd0 100644 > >> --- a/arch/loongarch/include/uapi/asm/kvm.h > >> +++ b/arch/loongarch/include/uapi/asm/kvm.h > >> @@ -81,7 +81,11 @@ struct kvm_fpu { > >> #define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT)) > >> #define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG) > >> #define KVM_IOC_CPUCFG(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CPUCFG, REG) > >> + > >> +/* Device Control API on vcpu fd */ > >> #define KVM_LOONGARCH_VCPU_CPUCFG 0 > >> +#define KVM_LOONGARCH_VCPU_PVTIME_CTRL 1 > >> +#define KVM_LOONGARCH_VCPU_PVTIME_GPA 0 > >> > >> struct kvm_debug_exit_arch { > >> }; > >> diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig > >> index c4ef2b4d9797..248744b4d086 100644 > >> --- a/arch/loongarch/kvm/Kconfig > >> +++ b/arch/loongarch/kvm/Kconfig > >> @@ -29,6 +29,7 @@ config KVM > >> select KVM_MMIO > >> select HAVE_KVM_READONLY_MEM > >> select KVM_XFER_TO_GUEST_WORK > >> + select SCHED_INFO > >> help > >> Support hosting virtualized guest machines using > >> hardware virtualization extensions. You will need > >> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c > >> index c86e099af5ca..e2abd97fb13f 100644 > >> --- a/arch/loongarch/kvm/exit.c > >> +++ b/arch/loongarch/kvm/exit.c > >> @@ -24,7 +24,7 @@ > >> static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) > >> { > >> int rd, rj; > >> - unsigned int index; > >> + unsigned int index, ret; > >> > >> if (inst.reg2_format.opcode != cpucfg_op) > >> return EMULATE_FAIL; > >> @@ -50,7 +50,10 @@ static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) > >> vcpu->arch.gprs[rd] = *(unsigned int *)KVM_SIGNATURE; > >> break; > >> case CPUCFG_KVM_FEATURE: > >> - vcpu->arch.gprs[rd] = KVM_FEATURE_IPI; > >> + ret = KVM_FEATURE_IPI; > >> + if (sched_info_on()) > > What about replacing it with your helper function kvm_pvtime_supported()? > Sure, will replace it with helper function kvm_pvtime_supported(). If you are sure this is the only issue, then needn't submit a new version. Huacai > > Regards > Bibo Mao > > > > Huacai > > > >> + ret |= KVM_FEATURE_STEAL_TIME; > >> + vcpu->arch.gprs[rd] = ret; > >> break; > >> default: > >> vcpu->arch.gprs[rd] = 0; > >> @@ -687,6 +690,34 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu) > >> return RESUME_GUEST; > >> } > >> > >> +static long kvm_save_notify(struct kvm_vcpu *vcpu) > >> +{ > >> + unsigned long id, data; > >> + > >> + id = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); > >> + data = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); > >> + switch (id) { > >> + case KVM_FEATURE_STEAL_TIME: > >> + if (!kvm_pvtime_supported()) > >> + return KVM_HCALL_INVALID_CODE; > >> + > >> + if (data & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) > >> + return KVM_HCALL_INVALID_PARAMETER; > >> + > >> + vcpu->arch.st.guest_addr = data; > >> + if (!(data & KVM_STEAL_PHYS_VALID)) > >> + break; > >> + > >> + vcpu->arch.st.last_steal = current->sched_info.run_delay; > >> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > >> + break; > >> + default: > >> + break; > >> + }; > >> + > >> + return 0; > >> +}; > >> + > >> /* > >> * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root. > >> * @vcpu: Virtual CPU context. > >> @@ -758,6 +789,9 @@ static void kvm_handle_service(struct kvm_vcpu *vcpu) > >> kvm_send_pv_ipi(vcpu); > >> ret = KVM_HCALL_SUCCESS; > >> break; > >> + case KVM_HCALL_FUNC_NOTIFY: > >> + ret = kvm_save_notify(vcpu); > >> + break; > >> default: > >> ret = KVM_HCALL_INVALID_CODE; > >> break; > >> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c > >> index 9e8030d45129..382796f1d3e6 100644 > >> --- a/arch/loongarch/kvm/vcpu.c > >> +++ b/arch/loongarch/kvm/vcpu.c > >> @@ -31,6 +31,117 @@ const struct kvm_stats_header kvm_vcpu_stats_header = { > >> sizeof(kvm_vcpu_stats_desc), > >> }; > >> > >> +static void kvm_update_stolen_time(struct kvm_vcpu *vcpu) > >> +{ > >> + struct kvm_steal_time __user *st; > >> + struct gfn_to_hva_cache *ghc; > >> + struct kvm_memslots *slots; > >> + gpa_t gpa; > >> + u64 steal; > >> + u32 version; > >> + > >> + ghc = &vcpu->arch.st.cache; > >> + gpa = vcpu->arch.st.guest_addr; > >> + if (!(gpa & KVM_STEAL_PHYS_VALID)) > >> + return; > >> + > >> + gpa &= KVM_STEAL_PHYS_MASK; > >> + slots = kvm_memslots(vcpu->kvm); > >> + if (slots->generation != ghc->generation || gpa != ghc->gpa) { > >> + if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, > >> + sizeof(*st))) { > >> + ghc->gpa = INVALID_GPA; > >> + return; > >> + } > >> + } > >> + > >> + st = (struct kvm_steal_time __user *)ghc->hva; > >> + unsafe_get_user(version, &st->version, out); > >> + if (version & 1) > >> + version += 1; > >> + version += 1; > >> + unsafe_put_user(version, &st->version, out); > >> + smp_wmb(); > >> + > >> + unsafe_get_user(steal, &st->steal, out); > >> + steal += current->sched_info.run_delay - > >> + vcpu->arch.st.last_steal; > >> + vcpu->arch.st.last_steal = current->sched_info.run_delay; > >> + unsafe_put_user(steal, &st->steal, out); > >> + > >> + smp_wmb(); > >> + version += 1; > >> + unsafe_put_user(version, &st->version, out); > >> +out: > >> + mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); > >> +} > >> + > >> +static int kvm_loongarch_pvtime_has_attr(struct kvm_vcpu *vcpu, > >> + struct kvm_device_attr *attr) > >> +{ > >> + if (!kvm_pvtime_supported() || > >> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > >> + return -ENXIO; > >> + > >> + return 0; > >> +} > >> + > >> +static int kvm_loongarch_pvtime_get_attr(struct kvm_vcpu *vcpu, > >> + struct kvm_device_attr *attr) > >> +{ > >> + u64 __user *user = (u64 __user *)attr->addr; > >> + u64 gpa; > >> + > >> + if (!kvm_pvtime_supported() || > >> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > >> + return -ENXIO; > >> + > >> + gpa = vcpu->arch.st.guest_addr; > >> + if (put_user(gpa, user)) > >> + return -EFAULT; > >> + > >> + return 0; > >> +} > >> + > >> +static int kvm_loongarch_pvtime_set_attr(struct kvm_vcpu *vcpu, > >> + struct kvm_device_attr *attr) > >> +{ > >> + u64 __user *user = (u64 __user *)attr->addr; > >> + struct kvm *kvm = vcpu->kvm; > >> + u64 gpa; > >> + int ret = 0; > >> + int idx; > >> + > >> + if (!kvm_pvtime_supported() || > >> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > >> + return -ENXIO; > >> + > >> + if (get_user(gpa, user)) > >> + return -EFAULT; > >> + > >> + if (gpa & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) > >> + return -EINVAL; > >> + > >> + if (!(gpa & KVM_STEAL_PHYS_VALID)) { > >> + vcpu->arch.st.guest_addr = gpa; > >> + return 0; > >> + } > >> + > >> + /* Check the address is in a valid memslot */ > >> + idx = srcu_read_lock(&kvm->srcu); > >> + if (kvm_is_error_hva(gfn_to_hva(kvm, gpa >> PAGE_SHIFT))) > >> + ret = -EINVAL; > >> + srcu_read_unlock(&kvm->srcu, idx); > >> + > >> + if (!ret) { > >> + vcpu->arch.st.guest_addr = gpa; > >> + vcpu->arch.st.last_steal = current->sched_info.run_delay; > >> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > >> + } > >> + > >> + return ret; > >> +} > >> + > >> /* > >> * kvm_check_requests - check and handle pending vCPU requests > >> * > >> @@ -48,6 +159,9 @@ static int kvm_check_requests(struct kvm_vcpu *vcpu) > >> if (kvm_dirty_ring_check_request(vcpu)) > >> return RESUME_HOST; > >> > >> + if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) > >> + kvm_update_stolen_time(vcpu); > >> + > >> return RESUME_GUEST; > >> } > >> > >> @@ -671,6 +785,9 @@ static int kvm_loongarch_vcpu_has_attr(struct kvm_vcpu *vcpu, > >> case KVM_LOONGARCH_VCPU_CPUCFG: > >> ret = kvm_loongarch_cpucfg_has_attr(vcpu, attr); > >> break; > >> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > >> + ret = kvm_loongarch_pvtime_has_attr(vcpu, attr); > >> + break; > >> default: > >> break; > >> } > >> @@ -703,6 +820,9 @@ static int kvm_loongarch_vcpu_get_attr(struct kvm_vcpu *vcpu, > >> case KVM_LOONGARCH_VCPU_CPUCFG: > >> ret = kvm_loongarch_get_cpucfg_attr(vcpu, attr); > >> break; > >> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > >> + ret = kvm_loongarch_pvtime_get_attr(vcpu, attr); > >> + break; > >> default: > >> break; > >> } > >> @@ -725,6 +845,9 @@ static int kvm_loongarch_vcpu_set_attr(struct kvm_vcpu *vcpu, > >> case KVM_LOONGARCH_VCPU_CPUCFG: > >> ret = kvm_loongarch_cpucfg_set_attr(vcpu, attr); > >> break; > >> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > >> + ret = kvm_loongarch_pvtime_set_attr(vcpu, attr); > >> + break; > >> default: > >> break; > >> } > >> @@ -1084,6 +1207,7 @@ static int _kvm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) > >> > >> /* Control guest page CCA attribute */ > >> change_csr_gcfg(CSR_GCFG_MATC_MASK, CSR_GCFG_MATC_ROOT); > >> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > >> > >> /* Don't bother restoring registers multiple times unless necessary */ > >> if (vcpu->arch.aux_inuse & KVM_LARCH_HWCSR_USABLE) > >> -- > >> 2.39.3 > >> >
On 2024/7/6 下午5:41, Huacai Chen wrote: > On Sat, Jul 6, 2024 at 2:59 PM maobibo <maobibo@loongson.cn> wrote: >> >> Huacai, >> >> On 2024/7/6 上午11:00, Huacai Chen wrote: >>> Hi, Bibo, >>> >>> On Fri, May 24, 2024 at 3:38 PM Bibo Mao <maobibo@loongson.cn> wrote: >>>> >>>> Steal time feature is added here in kvm side, VM can search supported >>>> features provided by KVM hypervisor, feature KVM_FEATURE_STEAL_TIME >>>> is added here. Like x86, steal time structure is saved in guest memory, >>>> one hypercall function KVM_HCALL_FUNC_NOTIFY is added to notify KVM to >>>> enable the feature. >>>> >>>> One cpu attr ioctl command KVM_LOONGARCH_VCPU_PVTIME_CTRL is added to >>>> save and restore base address of steal time structure when VM is migrated. >>>> >>>> Signed-off-by: Bibo Mao <maobibo@loongson.cn> >>>> --- >>>> arch/loongarch/include/asm/kvm_host.h | 7 ++ >>>> arch/loongarch/include/asm/kvm_para.h | 10 ++ >>>> arch/loongarch/include/asm/kvm_vcpu.h | 4 + >>>> arch/loongarch/include/asm/loongarch.h | 1 + >>>> arch/loongarch/include/uapi/asm/kvm.h | 4 + >>>> arch/loongarch/kvm/Kconfig | 1 + >>>> arch/loongarch/kvm/exit.c | 38 +++++++- >>>> arch/loongarch/kvm/vcpu.c | 124 +++++++++++++++++++++++++ >>>> 8 files changed, 187 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h >>>> index c87b6ea0ec47..2eb2f7572023 100644 >>>> --- a/arch/loongarch/include/asm/kvm_host.h >>>> +++ b/arch/loongarch/include/asm/kvm_host.h >>>> @@ -30,6 +30,7 @@ >>>> #define KVM_PRIVATE_MEM_SLOTS 0 >>>> >>>> #define KVM_HALT_POLL_NS_DEFAULT 500000 >>>> +#define KVM_REQ_STEAL_UPDATE KVM_ARCH_REQ(1) >>>> >>>> #define KVM_GUESTDBG_SW_BP_MASK \ >>>> (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) >>>> @@ -201,6 +202,12 @@ struct kvm_vcpu_arch { >>>> struct kvm_mp_state mp_state; >>>> /* cpucfg */ >>>> u32 cpucfg[KVM_MAX_CPUCFG_REGS]; >>>> + /* paravirt steal time */ >>>> + struct { >>>> + u64 guest_addr; >>>> + u64 last_steal; >>>> + struct gfn_to_hva_cache cache; >>>> + } st; >>>> }; >>>> >>>> static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg) >>>> diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h >>>> index 4ba2312e5f8c..a9ba8185d4af 100644 >>>> --- a/arch/loongarch/include/asm/kvm_para.h >>>> +++ b/arch/loongarch/include/asm/kvm_para.h >>>> @@ -14,6 +14,7 @@ >>>> >>>> #define KVM_HCALL_SERVICE HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SERVICE) >>>> #define KVM_HCALL_FUNC_IPI 1 >>>> +#define KVM_HCALL_FUNC_NOTIFY 2 >>>> >>>> #define KVM_HCALL_SWDBG HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SWDBG) >>>> >>>> @@ -24,6 +25,15 @@ >>>> #define KVM_HCALL_INVALID_CODE -1UL >>>> #define KVM_HCALL_INVALID_PARAMETER -2UL >>>> >>>> +#define KVM_STEAL_PHYS_VALID BIT_ULL(0) >>>> +#define KVM_STEAL_PHYS_MASK GENMASK_ULL(63, 6) >>>> +struct kvm_steal_time { >>>> + __u64 steal; >>>> + __u32 version; >>>> + __u32 flags; >>> I found that x86 has a preempted field here, in our internal repo the >>> LoongArch version also has this field. Moreover, >>> kvm_steal_time_set_preempted() and kvm_steal_time_clear_preempted() >>> seems needed. >> By my understanding, macro vcpu_is_preempted() is used together with pv >> spinlock, and pv spinlock depends on pv stealtime. So I think preempted >> flag is not part of pv stealtime, it is part of pv spinlock. >> >> We are going to add preempted field if pv spinlock is added. >>> >>>> + __u32 pad[12]; >>>> +}; >>>> + >>>> /* >>>> * Hypercall interface for KVM hypervisor >>>> * >>>> diff --git a/arch/loongarch/include/asm/kvm_vcpu.h b/arch/loongarch/include/asm/kvm_vcpu.h >>>> index 590a92cb5416..d7e51300a89f 100644 >>>> --- a/arch/loongarch/include/asm/kvm_vcpu.h >>>> +++ b/arch/loongarch/include/asm/kvm_vcpu.h >>>> @@ -120,4 +120,8 @@ static inline void kvm_write_reg(struct kvm_vcpu *vcpu, int num, unsigned long v >>>> vcpu->arch.gprs[num] = val; >>>> } >>>> >>>> +static inline bool kvm_pvtime_supported(void) >>>> +{ >>>> + return !!sched_info_on(); >>>> +} >>>> #endif /* __ASM_LOONGARCH_KVM_VCPU_H__ */ >>>> diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h >>>> index eb09adda54b7..7a4633ef284b 100644 >>>> --- a/arch/loongarch/include/asm/loongarch.h >>>> +++ b/arch/loongarch/include/asm/loongarch.h >>>> @@ -169,6 +169,7 @@ >>>> #define KVM_SIGNATURE "KVM\0" >>>> #define CPUCFG_KVM_FEATURE (CPUCFG_KVM_BASE + 4) >>>> #define KVM_FEATURE_IPI BIT(1) >>>> +#define KVM_FEATURE_STEAL_TIME BIT(2) >>>> >>>> #ifndef __ASSEMBLY__ >>>> >>>> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h >>>> index f9abef382317..ddc5cab0ffd0 100644 >>>> --- a/arch/loongarch/include/uapi/asm/kvm.h >>>> +++ b/arch/loongarch/include/uapi/asm/kvm.h >>>> @@ -81,7 +81,11 @@ struct kvm_fpu { >>>> #define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT)) >>>> #define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG) >>>> #define KVM_IOC_CPUCFG(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CPUCFG, REG) >>>> + >>>> +/* Device Control API on vcpu fd */ >>>> #define KVM_LOONGARCH_VCPU_CPUCFG 0 >>>> +#define KVM_LOONGARCH_VCPU_PVTIME_CTRL 1 >>>> +#define KVM_LOONGARCH_VCPU_PVTIME_GPA 0 >>>> >>>> struct kvm_debug_exit_arch { >>>> }; >>>> diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig >>>> index c4ef2b4d9797..248744b4d086 100644 >>>> --- a/arch/loongarch/kvm/Kconfig >>>> +++ b/arch/loongarch/kvm/Kconfig >>>> @@ -29,6 +29,7 @@ config KVM >>>> select KVM_MMIO >>>> select HAVE_KVM_READONLY_MEM >>>> select KVM_XFER_TO_GUEST_WORK >>>> + select SCHED_INFO >>>> help >>>> Support hosting virtualized guest machines using >>>> hardware virtualization extensions. You will need >>>> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c >>>> index c86e099af5ca..e2abd97fb13f 100644 >>>> --- a/arch/loongarch/kvm/exit.c >>>> +++ b/arch/loongarch/kvm/exit.c >>>> @@ -24,7 +24,7 @@ >>>> static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) >>>> { >>>> int rd, rj; >>>> - unsigned int index; >>>> + unsigned int index, ret; >>>> >>>> if (inst.reg2_format.opcode != cpucfg_op) >>>> return EMULATE_FAIL; >>>> @@ -50,7 +50,10 @@ static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) >>>> vcpu->arch.gprs[rd] = *(unsigned int *)KVM_SIGNATURE; >>>> break; >>>> case CPUCFG_KVM_FEATURE: >>>> - vcpu->arch.gprs[rd] = KVM_FEATURE_IPI; >>>> + ret = KVM_FEATURE_IPI; >>>> + if (sched_info_on()) >>> What about replacing it with your helper function kvm_pvtime_supported()? >> Sure, will replace it with helper function kvm_pvtime_supported(). > If you are sure this is the only issue, then needn't submit a new version. OK, thanks. By searching orginal submit of vcpu_is_preempt(), it can be located at https://lore.kernel.org/lkml/1477642287-24104-1-git-send-email-xinhui.pan@linux.vnet.ibm.com/ It is separated one, only that is depends on pv-spinlock and pv-stealtime. And there is no capability indicator for guest kernel, it is enabled by default. Regards Bibo Mao > > Huacai > >> >> Regards >> Bibo Mao >>> >>> Huacai >>> >>>> + ret |= KVM_FEATURE_STEAL_TIME; >>>> + vcpu->arch.gprs[rd] = ret; >>>> break; >>>> default: >>>> vcpu->arch.gprs[rd] = 0; >>>> @@ -687,6 +690,34 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu) >>>> return RESUME_GUEST; >>>> } >>>> >>>> +static long kvm_save_notify(struct kvm_vcpu *vcpu) >>>> +{ >>>> + unsigned long id, data; >>>> + >>>> + id = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); >>>> + data = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); >>>> + switch (id) { >>>> + case KVM_FEATURE_STEAL_TIME: >>>> + if (!kvm_pvtime_supported()) >>>> + return KVM_HCALL_INVALID_CODE; >>>> + >>>> + if (data & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) >>>> + return KVM_HCALL_INVALID_PARAMETER; >>>> + >>>> + vcpu->arch.st.guest_addr = data; >>>> + if (!(data & KVM_STEAL_PHYS_VALID)) >>>> + break; >>>> + >>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >>>> + break; >>>> + default: >>>> + break; >>>> + }; >>>> + >>>> + return 0; >>>> +}; >>>> + >>>> /* >>>> * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root. >>>> * @vcpu: Virtual CPU context. >>>> @@ -758,6 +789,9 @@ static void kvm_handle_service(struct kvm_vcpu *vcpu) >>>> kvm_send_pv_ipi(vcpu); >>>> ret = KVM_HCALL_SUCCESS; >>>> break; >>>> + case KVM_HCALL_FUNC_NOTIFY: >>>> + ret = kvm_save_notify(vcpu); >>>> + break; >>>> default: >>>> ret = KVM_HCALL_INVALID_CODE; >>>> break; >>>> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c >>>> index 9e8030d45129..382796f1d3e6 100644 >>>> --- a/arch/loongarch/kvm/vcpu.c >>>> +++ b/arch/loongarch/kvm/vcpu.c >>>> @@ -31,6 +31,117 @@ const struct kvm_stats_header kvm_vcpu_stats_header = { >>>> sizeof(kvm_vcpu_stats_desc), >>>> }; >>>> >>>> +static void kvm_update_stolen_time(struct kvm_vcpu *vcpu) >>>> +{ >>>> + struct kvm_steal_time __user *st; >>>> + struct gfn_to_hva_cache *ghc; >>>> + struct kvm_memslots *slots; >>>> + gpa_t gpa; >>>> + u64 steal; >>>> + u32 version; >>>> + >>>> + ghc = &vcpu->arch.st.cache; >>>> + gpa = vcpu->arch.st.guest_addr; >>>> + if (!(gpa & KVM_STEAL_PHYS_VALID)) >>>> + return; >>>> + >>>> + gpa &= KVM_STEAL_PHYS_MASK; >>>> + slots = kvm_memslots(vcpu->kvm); >>>> + if (slots->generation != ghc->generation || gpa != ghc->gpa) { >>>> + if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, >>>> + sizeof(*st))) { >>>> + ghc->gpa = INVALID_GPA; >>>> + return; >>>> + } >>>> + } >>>> + >>>> + st = (struct kvm_steal_time __user *)ghc->hva; >>>> + unsafe_get_user(version, &st->version, out); >>>> + if (version & 1) >>>> + version += 1; >>>> + version += 1; >>>> + unsafe_put_user(version, &st->version, out); >>>> + smp_wmb(); >>>> + >>>> + unsafe_get_user(steal, &st->steal, out); >>>> + steal += current->sched_info.run_delay - >>>> + vcpu->arch.st.last_steal; >>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >>>> + unsafe_put_user(steal, &st->steal, out); >>>> + >>>> + smp_wmb(); >>>> + version += 1; >>>> + unsafe_put_user(version, &st->version, out); >>>> +out: >>>> + mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); >>>> +} >>>> + >>>> +static int kvm_loongarch_pvtime_has_attr(struct kvm_vcpu *vcpu, >>>> + struct kvm_device_attr *attr) >>>> +{ >>>> + if (!kvm_pvtime_supported() || >>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >>>> + return -ENXIO; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static int kvm_loongarch_pvtime_get_attr(struct kvm_vcpu *vcpu, >>>> + struct kvm_device_attr *attr) >>>> +{ >>>> + u64 __user *user = (u64 __user *)attr->addr; >>>> + u64 gpa; >>>> + >>>> + if (!kvm_pvtime_supported() || >>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >>>> + return -ENXIO; >>>> + >>>> + gpa = vcpu->arch.st.guest_addr; >>>> + if (put_user(gpa, user)) >>>> + return -EFAULT; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static int kvm_loongarch_pvtime_set_attr(struct kvm_vcpu *vcpu, >>>> + struct kvm_device_attr *attr) >>>> +{ >>>> + u64 __user *user = (u64 __user *)attr->addr; >>>> + struct kvm *kvm = vcpu->kvm; >>>> + u64 gpa; >>>> + int ret = 0; >>>> + int idx; >>>> + >>>> + if (!kvm_pvtime_supported() || >>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >>>> + return -ENXIO; >>>> + >>>> + if (get_user(gpa, user)) >>>> + return -EFAULT; >>>> + >>>> + if (gpa & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) >>>> + return -EINVAL; >>>> + >>>> + if (!(gpa & KVM_STEAL_PHYS_VALID)) { >>>> + vcpu->arch.st.guest_addr = gpa; >>>> + return 0; >>>> + } >>>> + >>>> + /* Check the address is in a valid memslot */ >>>> + idx = srcu_read_lock(&kvm->srcu); >>>> + if (kvm_is_error_hva(gfn_to_hva(kvm, gpa >> PAGE_SHIFT))) >>>> + ret = -EINVAL; >>>> + srcu_read_unlock(&kvm->srcu, idx); >>>> + >>>> + if (!ret) { >>>> + vcpu->arch.st.guest_addr = gpa; >>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >>>> + } >>>> + >>>> + return ret; >>>> +} >>>> + >>>> /* >>>> * kvm_check_requests - check and handle pending vCPU requests >>>> * >>>> @@ -48,6 +159,9 @@ static int kvm_check_requests(struct kvm_vcpu *vcpu) >>>> if (kvm_dirty_ring_check_request(vcpu)) >>>> return RESUME_HOST; >>>> >>>> + if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) >>>> + kvm_update_stolen_time(vcpu); >>>> + >>>> return RESUME_GUEST; >>>> } >>>> >>>> @@ -671,6 +785,9 @@ static int kvm_loongarch_vcpu_has_attr(struct kvm_vcpu *vcpu, >>>> case KVM_LOONGARCH_VCPU_CPUCFG: >>>> ret = kvm_loongarch_cpucfg_has_attr(vcpu, attr); >>>> break; >>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >>>> + ret = kvm_loongarch_pvtime_has_attr(vcpu, attr); >>>> + break; >>>> default: >>>> break; >>>> } >>>> @@ -703,6 +820,9 @@ static int kvm_loongarch_vcpu_get_attr(struct kvm_vcpu *vcpu, >>>> case KVM_LOONGARCH_VCPU_CPUCFG: >>>> ret = kvm_loongarch_get_cpucfg_attr(vcpu, attr); >>>> break; >>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >>>> + ret = kvm_loongarch_pvtime_get_attr(vcpu, attr); >>>> + break; >>>> default: >>>> break; >>>> } >>>> @@ -725,6 +845,9 @@ static int kvm_loongarch_vcpu_set_attr(struct kvm_vcpu *vcpu, >>>> case KVM_LOONGARCH_VCPU_CPUCFG: >>>> ret = kvm_loongarch_cpucfg_set_attr(vcpu, attr); >>>> break; >>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >>>> + ret = kvm_loongarch_pvtime_set_attr(vcpu, attr); >>>> + break; >>>> default: >>>> break; >>>> } >>>> @@ -1084,6 +1207,7 @@ static int _kvm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) >>>> >>>> /* Control guest page CCA attribute */ >>>> change_csr_gcfg(CSR_GCFG_MATC_MASK, CSR_GCFG_MATC_ROOT); >>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >>>> >>>> /* Don't bother restoring registers multiple times unless necessary */ >>>> if (vcpu->arch.aux_inuse & KVM_LARCH_HWCSR_USABLE) >>>> -- >>>> 2.39.3 >>>> >>
On Mon, Jul 8, 2024 at 9:16 AM maobibo <maobibo@loongson.cn> wrote: > > > > On 2024/7/6 下午5:41, Huacai Chen wrote: > > On Sat, Jul 6, 2024 at 2:59 PM maobibo <maobibo@loongson.cn> wrote: > >> > >> Huacai, > >> > >> On 2024/7/6 上午11:00, Huacai Chen wrote: > >>> Hi, Bibo, > >>> > >>> On Fri, May 24, 2024 at 3:38 PM Bibo Mao <maobibo@loongson.cn> wrote: > >>>> > >>>> Steal time feature is added here in kvm side, VM can search supported > >>>> features provided by KVM hypervisor, feature KVM_FEATURE_STEAL_TIME > >>>> is added here. Like x86, steal time structure is saved in guest memory, > >>>> one hypercall function KVM_HCALL_FUNC_NOTIFY is added to notify KVM to > >>>> enable the feature. > >>>> > >>>> One cpu attr ioctl command KVM_LOONGARCH_VCPU_PVTIME_CTRL is added to > >>>> save and restore base address of steal time structure when VM is migrated. > >>>> > >>>> Signed-off-by: Bibo Mao <maobibo@loongson.cn> > >>>> --- > >>>> arch/loongarch/include/asm/kvm_host.h | 7 ++ > >>>> arch/loongarch/include/asm/kvm_para.h | 10 ++ > >>>> arch/loongarch/include/asm/kvm_vcpu.h | 4 + > >>>> arch/loongarch/include/asm/loongarch.h | 1 + > >>>> arch/loongarch/include/uapi/asm/kvm.h | 4 + > >>>> arch/loongarch/kvm/Kconfig | 1 + > >>>> arch/loongarch/kvm/exit.c | 38 +++++++- > >>>> arch/loongarch/kvm/vcpu.c | 124 +++++++++++++++++++++++++ > >>>> 8 files changed, 187 insertions(+), 2 deletions(-) > >>>> > >>>> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h > >>>> index c87b6ea0ec47..2eb2f7572023 100644 > >>>> --- a/arch/loongarch/include/asm/kvm_host.h > >>>> +++ b/arch/loongarch/include/asm/kvm_host.h > >>>> @@ -30,6 +30,7 @@ > >>>> #define KVM_PRIVATE_MEM_SLOTS 0 > >>>> > >>>> #define KVM_HALT_POLL_NS_DEFAULT 500000 > >>>> +#define KVM_REQ_STEAL_UPDATE KVM_ARCH_REQ(1) > >>>> > >>>> #define KVM_GUESTDBG_SW_BP_MASK \ > >>>> (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) > >>>> @@ -201,6 +202,12 @@ struct kvm_vcpu_arch { > >>>> struct kvm_mp_state mp_state; > >>>> /* cpucfg */ > >>>> u32 cpucfg[KVM_MAX_CPUCFG_REGS]; > >>>> + /* paravirt steal time */ > >>>> + struct { > >>>> + u64 guest_addr; > >>>> + u64 last_steal; > >>>> + struct gfn_to_hva_cache cache; > >>>> + } st; > >>>> }; > >>>> > >>>> static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg) > >>>> diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h > >>>> index 4ba2312e5f8c..a9ba8185d4af 100644 > >>>> --- a/arch/loongarch/include/asm/kvm_para.h > >>>> +++ b/arch/loongarch/include/asm/kvm_para.h > >>>> @@ -14,6 +14,7 @@ > >>>> > >>>> #define KVM_HCALL_SERVICE HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SERVICE) > >>>> #define KVM_HCALL_FUNC_IPI 1 > >>>> +#define KVM_HCALL_FUNC_NOTIFY 2 > >>>> > >>>> #define KVM_HCALL_SWDBG HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SWDBG) > >>>> > >>>> @@ -24,6 +25,15 @@ > >>>> #define KVM_HCALL_INVALID_CODE -1UL > >>>> #define KVM_HCALL_INVALID_PARAMETER -2UL > >>>> > >>>> +#define KVM_STEAL_PHYS_VALID BIT_ULL(0) > >>>> +#define KVM_STEAL_PHYS_MASK GENMASK_ULL(63, 6) > >>>> +struct kvm_steal_time { > >>>> + __u64 steal; > >>>> + __u32 version; > >>>> + __u32 flags; > >>> I found that x86 has a preempted field here, in our internal repo the > >>> LoongArch version also has this field. Moreover, > >>> kvm_steal_time_set_preempted() and kvm_steal_time_clear_preempted() > >>> seems needed. > >> By my understanding, macro vcpu_is_preempted() is used together with pv > >> spinlock, and pv spinlock depends on pv stealtime. So I think preempted > >> flag is not part of pv stealtime, it is part of pv spinlock. > >> > >> We are going to add preempted field if pv spinlock is added. > >>> > >>>> + __u32 pad[12]; > >>>> +}; > >>>> + > >>>> /* > >>>> * Hypercall interface for KVM hypervisor > >>>> * > >>>> diff --git a/arch/loongarch/include/asm/kvm_vcpu.h b/arch/loongarch/include/asm/kvm_vcpu.h > >>>> index 590a92cb5416..d7e51300a89f 100644 > >>>> --- a/arch/loongarch/include/asm/kvm_vcpu.h > >>>> +++ b/arch/loongarch/include/asm/kvm_vcpu.h > >>>> @@ -120,4 +120,8 @@ static inline void kvm_write_reg(struct kvm_vcpu *vcpu, int num, unsigned long v > >>>> vcpu->arch.gprs[num] = val; > >>>> } > >>>> > >>>> +static inline bool kvm_pvtime_supported(void) > >>>> +{ > >>>> + return !!sched_info_on(); > >>>> +} > >>>> #endif /* __ASM_LOONGARCH_KVM_VCPU_H__ */ > >>>> diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h > >>>> index eb09adda54b7..7a4633ef284b 100644 > >>>> --- a/arch/loongarch/include/asm/loongarch.h > >>>> +++ b/arch/loongarch/include/asm/loongarch.h > >>>> @@ -169,6 +169,7 @@ > >>>> #define KVM_SIGNATURE "KVM\0" > >>>> #define CPUCFG_KVM_FEATURE (CPUCFG_KVM_BASE + 4) > >>>> #define KVM_FEATURE_IPI BIT(1) > >>>> +#define KVM_FEATURE_STEAL_TIME BIT(2) > >>>> > >>>> #ifndef __ASSEMBLY__ > >>>> > >>>> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h > >>>> index f9abef382317..ddc5cab0ffd0 100644 > >>>> --- a/arch/loongarch/include/uapi/asm/kvm.h > >>>> +++ b/arch/loongarch/include/uapi/asm/kvm.h > >>>> @@ -81,7 +81,11 @@ struct kvm_fpu { > >>>> #define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT)) > >>>> #define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG) > >>>> #define KVM_IOC_CPUCFG(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CPUCFG, REG) > >>>> + > >>>> +/* Device Control API on vcpu fd */ > >>>> #define KVM_LOONGARCH_VCPU_CPUCFG 0 > >>>> +#define KVM_LOONGARCH_VCPU_PVTIME_CTRL 1 > >>>> +#define KVM_LOONGARCH_VCPU_PVTIME_GPA 0 > >>>> > >>>> struct kvm_debug_exit_arch { > >>>> }; > >>>> diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig > >>>> index c4ef2b4d9797..248744b4d086 100644 > >>>> --- a/arch/loongarch/kvm/Kconfig > >>>> +++ b/arch/loongarch/kvm/Kconfig > >>>> @@ -29,6 +29,7 @@ config KVM > >>>> select KVM_MMIO > >>>> select HAVE_KVM_READONLY_MEM > >>>> select KVM_XFER_TO_GUEST_WORK > >>>> + select SCHED_INFO > >>>> help > >>>> Support hosting virtualized guest machines using > >>>> hardware virtualization extensions. You will need > >>>> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c > >>>> index c86e099af5ca..e2abd97fb13f 100644 > >>>> --- a/arch/loongarch/kvm/exit.c > >>>> +++ b/arch/loongarch/kvm/exit.c > >>>> @@ -24,7 +24,7 @@ > >>>> static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) > >>>> { > >>>> int rd, rj; > >>>> - unsigned int index; > >>>> + unsigned int index, ret; > >>>> > >>>> if (inst.reg2_format.opcode != cpucfg_op) > >>>> return EMULATE_FAIL; > >>>> @@ -50,7 +50,10 @@ static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) > >>>> vcpu->arch.gprs[rd] = *(unsigned int *)KVM_SIGNATURE; > >>>> break; > >>>> case CPUCFG_KVM_FEATURE: > >>>> - vcpu->arch.gprs[rd] = KVM_FEATURE_IPI; > >>>> + ret = KVM_FEATURE_IPI; > >>>> + if (sched_info_on()) > >>> What about replacing it with your helper function kvm_pvtime_supported()? > >> Sure, will replace it with helper function kvm_pvtime_supported(). > > If you are sure this is the only issue, then needn't submit a new version. > OK, thanks. > > By searching orginal submit of vcpu_is_preempt(), it can be located at > https://lore.kernel.org/lkml/1477642287-24104-1-git-send-email-xinhui.pan@linux.vnet.ibm.com/ > > It is separated one, only that is depends on pv-spinlock and > pv-stealtime. And there is no capability indicator for guest kernel, it > is enabled by default. Series applied with some modifications here, you can double-check the correctness. https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git/log/?h=loongarch-kvm Huacai > > Regards > Bibo Mao > > > > > Huacai > > > >> > >> Regards > >> Bibo Mao > >>> > >>> Huacai > >>> > >>>> + ret |= KVM_FEATURE_STEAL_TIME; > >>>> + vcpu->arch.gprs[rd] = ret; > >>>> break; > >>>> default: > >>>> vcpu->arch.gprs[rd] = 0; > >>>> @@ -687,6 +690,34 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu) > >>>> return RESUME_GUEST; > >>>> } > >>>> > >>>> +static long kvm_save_notify(struct kvm_vcpu *vcpu) > >>>> +{ > >>>> + unsigned long id, data; > >>>> + > >>>> + id = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); > >>>> + data = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); > >>>> + switch (id) { > >>>> + case KVM_FEATURE_STEAL_TIME: > >>>> + if (!kvm_pvtime_supported()) > >>>> + return KVM_HCALL_INVALID_CODE; > >>>> + > >>>> + if (data & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) > >>>> + return KVM_HCALL_INVALID_PARAMETER; > >>>> + > >>>> + vcpu->arch.st.guest_addr = data; > >>>> + if (!(data & KVM_STEAL_PHYS_VALID)) > >>>> + break; > >>>> + > >>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; > >>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > >>>> + break; > >>>> + default: > >>>> + break; > >>>> + }; > >>>> + > >>>> + return 0; > >>>> +}; > >>>> + > >>>> /* > >>>> * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root. > >>>> * @vcpu: Virtual CPU context. > >>>> @@ -758,6 +789,9 @@ static void kvm_handle_service(struct kvm_vcpu *vcpu) > >>>> kvm_send_pv_ipi(vcpu); > >>>> ret = KVM_HCALL_SUCCESS; > >>>> break; > >>>> + case KVM_HCALL_FUNC_NOTIFY: > >>>> + ret = kvm_save_notify(vcpu); > >>>> + break; > >>>> default: > >>>> ret = KVM_HCALL_INVALID_CODE; > >>>> break; > >>>> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c > >>>> index 9e8030d45129..382796f1d3e6 100644 > >>>> --- a/arch/loongarch/kvm/vcpu.c > >>>> +++ b/arch/loongarch/kvm/vcpu.c > >>>> @@ -31,6 +31,117 @@ const struct kvm_stats_header kvm_vcpu_stats_header = { > >>>> sizeof(kvm_vcpu_stats_desc), > >>>> }; > >>>> > >>>> +static void kvm_update_stolen_time(struct kvm_vcpu *vcpu) > >>>> +{ > >>>> + struct kvm_steal_time __user *st; > >>>> + struct gfn_to_hva_cache *ghc; > >>>> + struct kvm_memslots *slots; > >>>> + gpa_t gpa; > >>>> + u64 steal; > >>>> + u32 version; > >>>> + > >>>> + ghc = &vcpu->arch.st.cache; > >>>> + gpa = vcpu->arch.st.guest_addr; > >>>> + if (!(gpa & KVM_STEAL_PHYS_VALID)) > >>>> + return; > >>>> + > >>>> + gpa &= KVM_STEAL_PHYS_MASK; > >>>> + slots = kvm_memslots(vcpu->kvm); > >>>> + if (slots->generation != ghc->generation || gpa != ghc->gpa) { > >>>> + if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, > >>>> + sizeof(*st))) { > >>>> + ghc->gpa = INVALID_GPA; > >>>> + return; > >>>> + } > >>>> + } > >>>> + > >>>> + st = (struct kvm_steal_time __user *)ghc->hva; > >>>> + unsafe_get_user(version, &st->version, out); > >>>> + if (version & 1) > >>>> + version += 1; > >>>> + version += 1; > >>>> + unsafe_put_user(version, &st->version, out); > >>>> + smp_wmb(); > >>>> + > >>>> + unsafe_get_user(steal, &st->steal, out); > >>>> + steal += current->sched_info.run_delay - > >>>> + vcpu->arch.st.last_steal; > >>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; > >>>> + unsafe_put_user(steal, &st->steal, out); > >>>> + > >>>> + smp_wmb(); > >>>> + version += 1; > >>>> + unsafe_put_user(version, &st->version, out); > >>>> +out: > >>>> + mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); > >>>> +} > >>>> + > >>>> +static int kvm_loongarch_pvtime_has_attr(struct kvm_vcpu *vcpu, > >>>> + struct kvm_device_attr *attr) > >>>> +{ > >>>> + if (!kvm_pvtime_supported() || > >>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > >>>> + return -ENXIO; > >>>> + > >>>> + return 0; > >>>> +} > >>>> + > >>>> +static int kvm_loongarch_pvtime_get_attr(struct kvm_vcpu *vcpu, > >>>> + struct kvm_device_attr *attr) > >>>> +{ > >>>> + u64 __user *user = (u64 __user *)attr->addr; > >>>> + u64 gpa; > >>>> + > >>>> + if (!kvm_pvtime_supported() || > >>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > >>>> + return -ENXIO; > >>>> + > >>>> + gpa = vcpu->arch.st.guest_addr; > >>>> + if (put_user(gpa, user)) > >>>> + return -EFAULT; > >>>> + > >>>> + return 0; > >>>> +} > >>>> + > >>>> +static int kvm_loongarch_pvtime_set_attr(struct kvm_vcpu *vcpu, > >>>> + struct kvm_device_attr *attr) > >>>> +{ > >>>> + u64 __user *user = (u64 __user *)attr->addr; > >>>> + struct kvm *kvm = vcpu->kvm; > >>>> + u64 gpa; > >>>> + int ret = 0; > >>>> + int idx; > >>>> + > >>>> + if (!kvm_pvtime_supported() || > >>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) > >>>> + return -ENXIO; > >>>> + > >>>> + if (get_user(gpa, user)) > >>>> + return -EFAULT; > >>>> + > >>>> + if (gpa & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) > >>>> + return -EINVAL; > >>>> + > >>>> + if (!(gpa & KVM_STEAL_PHYS_VALID)) { > >>>> + vcpu->arch.st.guest_addr = gpa; > >>>> + return 0; > >>>> + } > >>>> + > >>>> + /* Check the address is in a valid memslot */ > >>>> + idx = srcu_read_lock(&kvm->srcu); > >>>> + if (kvm_is_error_hva(gfn_to_hva(kvm, gpa >> PAGE_SHIFT))) > >>>> + ret = -EINVAL; > >>>> + srcu_read_unlock(&kvm->srcu, idx); > >>>> + > >>>> + if (!ret) { > >>>> + vcpu->arch.st.guest_addr = gpa; > >>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; > >>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > >>>> + } > >>>> + > >>>> + return ret; > >>>> +} > >>>> + > >>>> /* > >>>> * kvm_check_requests - check and handle pending vCPU requests > >>>> * > >>>> @@ -48,6 +159,9 @@ static int kvm_check_requests(struct kvm_vcpu *vcpu) > >>>> if (kvm_dirty_ring_check_request(vcpu)) > >>>> return RESUME_HOST; > >>>> > >>>> + if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) > >>>> + kvm_update_stolen_time(vcpu); > >>>> + > >>>> return RESUME_GUEST; > >>>> } > >>>> > >>>> @@ -671,6 +785,9 @@ static int kvm_loongarch_vcpu_has_attr(struct kvm_vcpu *vcpu, > >>>> case KVM_LOONGARCH_VCPU_CPUCFG: > >>>> ret = kvm_loongarch_cpucfg_has_attr(vcpu, attr); > >>>> break; > >>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > >>>> + ret = kvm_loongarch_pvtime_has_attr(vcpu, attr); > >>>> + break; > >>>> default: > >>>> break; > >>>> } > >>>> @@ -703,6 +820,9 @@ static int kvm_loongarch_vcpu_get_attr(struct kvm_vcpu *vcpu, > >>>> case KVM_LOONGARCH_VCPU_CPUCFG: > >>>> ret = kvm_loongarch_get_cpucfg_attr(vcpu, attr); > >>>> break; > >>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > >>>> + ret = kvm_loongarch_pvtime_get_attr(vcpu, attr); > >>>> + break; > >>>> default: > >>>> break; > >>>> } > >>>> @@ -725,6 +845,9 @@ static int kvm_loongarch_vcpu_set_attr(struct kvm_vcpu *vcpu, > >>>> case KVM_LOONGARCH_VCPU_CPUCFG: > >>>> ret = kvm_loongarch_cpucfg_set_attr(vcpu, attr); > >>>> break; > >>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: > >>>> + ret = kvm_loongarch_pvtime_set_attr(vcpu, attr); > >>>> + break; > >>>> default: > >>>> break; > >>>> } > >>>> @@ -1084,6 +1207,7 @@ static int _kvm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) > >>>> > >>>> /* Control guest page CCA attribute */ > >>>> change_csr_gcfg(CSR_GCFG_MATC_MASK, CSR_GCFG_MATC_ROOT); > >>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); > >>>> > >>>> /* Don't bother restoring registers multiple times unless necessary */ > >>>> if (vcpu->arch.aux_inuse & KVM_LARCH_HWCSR_USABLE) > >>>> -- > >>>> 2.39.3 > >>>> > >> > >
On 2024/7/8 下午5:47, Huacai Chen wrote: > On Mon, Jul 8, 2024 at 9:16 AM maobibo <maobibo@loongson.cn> wrote: >> >> >> >> On 2024/7/6 下午5:41, Huacai Chen wrote: >>> On Sat, Jul 6, 2024 at 2:59 PM maobibo <maobibo@loongson.cn> wrote: >>>> >>>> Huacai, >>>> >>>> On 2024/7/6 上午11:00, Huacai Chen wrote: >>>>> Hi, Bibo, >>>>> >>>>> On Fri, May 24, 2024 at 3:38 PM Bibo Mao <maobibo@loongson.cn> wrote: >>>>>> >>>>>> Steal time feature is added here in kvm side, VM can search supported >>>>>> features provided by KVM hypervisor, feature KVM_FEATURE_STEAL_TIME >>>>>> is added here. Like x86, steal time structure is saved in guest memory, >>>>>> one hypercall function KVM_HCALL_FUNC_NOTIFY is added to notify KVM to >>>>>> enable the feature. >>>>>> >>>>>> One cpu attr ioctl command KVM_LOONGARCH_VCPU_PVTIME_CTRL is added to >>>>>> save and restore base address of steal time structure when VM is migrated. >>>>>> >>>>>> Signed-off-by: Bibo Mao <maobibo@loongson.cn> >>>>>> --- >>>>>> arch/loongarch/include/asm/kvm_host.h | 7 ++ >>>>>> arch/loongarch/include/asm/kvm_para.h | 10 ++ >>>>>> arch/loongarch/include/asm/kvm_vcpu.h | 4 + >>>>>> arch/loongarch/include/asm/loongarch.h | 1 + >>>>>> arch/loongarch/include/uapi/asm/kvm.h | 4 + >>>>>> arch/loongarch/kvm/Kconfig | 1 + >>>>>> arch/loongarch/kvm/exit.c | 38 +++++++- >>>>>> arch/loongarch/kvm/vcpu.c | 124 +++++++++++++++++++++++++ >>>>>> 8 files changed, 187 insertions(+), 2 deletions(-) >>>>>> >>>>>> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h >>>>>> index c87b6ea0ec47..2eb2f7572023 100644 >>>>>> --- a/arch/loongarch/include/asm/kvm_host.h >>>>>> +++ b/arch/loongarch/include/asm/kvm_host.h >>>>>> @@ -30,6 +30,7 @@ >>>>>> #define KVM_PRIVATE_MEM_SLOTS 0 >>>>>> >>>>>> #define KVM_HALT_POLL_NS_DEFAULT 500000 >>>>>> +#define KVM_REQ_STEAL_UPDATE KVM_ARCH_REQ(1) >>>>>> >>>>>> #define KVM_GUESTDBG_SW_BP_MASK \ >>>>>> (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) >>>>>> @@ -201,6 +202,12 @@ struct kvm_vcpu_arch { >>>>>> struct kvm_mp_state mp_state; >>>>>> /* cpucfg */ >>>>>> u32 cpucfg[KVM_MAX_CPUCFG_REGS]; >>>>>> + /* paravirt steal time */ >>>>>> + struct { >>>>>> + u64 guest_addr; >>>>>> + u64 last_steal; >>>>>> + struct gfn_to_hva_cache cache; >>>>>> + } st; >>>>>> }; >>>>>> >>>>>> static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg) >>>>>> diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h >>>>>> index 4ba2312e5f8c..a9ba8185d4af 100644 >>>>>> --- a/arch/loongarch/include/asm/kvm_para.h >>>>>> +++ b/arch/loongarch/include/asm/kvm_para.h >>>>>> @@ -14,6 +14,7 @@ >>>>>> >>>>>> #define KVM_HCALL_SERVICE HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SERVICE) >>>>>> #define KVM_HCALL_FUNC_IPI 1 >>>>>> +#define KVM_HCALL_FUNC_NOTIFY 2 >>>>>> >>>>>> #define KVM_HCALL_SWDBG HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SWDBG) >>>>>> >>>>>> @@ -24,6 +25,15 @@ >>>>>> #define KVM_HCALL_INVALID_CODE -1UL >>>>>> #define KVM_HCALL_INVALID_PARAMETER -2UL >>>>>> >>>>>> +#define KVM_STEAL_PHYS_VALID BIT_ULL(0) >>>>>> +#define KVM_STEAL_PHYS_MASK GENMASK_ULL(63, 6) >>>>>> +struct kvm_steal_time { >>>>>> + __u64 steal; >>>>>> + __u32 version; >>>>>> + __u32 flags; >>>>> I found that x86 has a preempted field here, in our internal repo the >>>>> LoongArch version also has this field. Moreover, >>>>> kvm_steal_time_set_preempted() and kvm_steal_time_clear_preempted() >>>>> seems needed. >>>> By my understanding, macro vcpu_is_preempted() is used together with pv >>>> spinlock, and pv spinlock depends on pv stealtime. So I think preempted >>>> flag is not part of pv stealtime, it is part of pv spinlock. >>>> >>>> We are going to add preempted field if pv spinlock is added. >>>>> >>>>>> + __u32 pad[12]; >>>>>> +}; >>>>>> + >>>>>> /* >>>>>> * Hypercall interface for KVM hypervisor >>>>>> * >>>>>> diff --git a/arch/loongarch/include/asm/kvm_vcpu.h b/arch/loongarch/include/asm/kvm_vcpu.h >>>>>> index 590a92cb5416..d7e51300a89f 100644 >>>>>> --- a/arch/loongarch/include/asm/kvm_vcpu.h >>>>>> +++ b/arch/loongarch/include/asm/kvm_vcpu.h >>>>>> @@ -120,4 +120,8 @@ static inline void kvm_write_reg(struct kvm_vcpu *vcpu, int num, unsigned long v >>>>>> vcpu->arch.gprs[num] = val; >>>>>> } >>>>>> >>>>>> +static inline bool kvm_pvtime_supported(void) >>>>>> +{ >>>>>> + return !!sched_info_on(); >>>>>> +} >>>>>> #endif /* __ASM_LOONGARCH_KVM_VCPU_H__ */ >>>>>> diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h >>>>>> index eb09adda54b7..7a4633ef284b 100644 >>>>>> --- a/arch/loongarch/include/asm/loongarch.h >>>>>> +++ b/arch/loongarch/include/asm/loongarch.h >>>>>> @@ -169,6 +169,7 @@ >>>>>> #define KVM_SIGNATURE "KVM\0" >>>>>> #define CPUCFG_KVM_FEATURE (CPUCFG_KVM_BASE + 4) >>>>>> #define KVM_FEATURE_IPI BIT(1) >>>>>> +#define KVM_FEATURE_STEAL_TIME BIT(2) >>>>>> >>>>>> #ifndef __ASSEMBLY__ >>>>>> >>>>>> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h >>>>>> index f9abef382317..ddc5cab0ffd0 100644 >>>>>> --- a/arch/loongarch/include/uapi/asm/kvm.h >>>>>> +++ b/arch/loongarch/include/uapi/asm/kvm.h >>>>>> @@ -81,7 +81,11 @@ struct kvm_fpu { >>>>>> #define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT)) >>>>>> #define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG) >>>>>> #define KVM_IOC_CPUCFG(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CPUCFG, REG) >>>>>> + >>>>>> +/* Device Control API on vcpu fd */ >>>>>> #define KVM_LOONGARCH_VCPU_CPUCFG 0 >>>>>> +#define KVM_LOONGARCH_VCPU_PVTIME_CTRL 1 >>>>>> +#define KVM_LOONGARCH_VCPU_PVTIME_GPA 0 >>>>>> >>>>>> struct kvm_debug_exit_arch { >>>>>> }; >>>>>> diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig >>>>>> index c4ef2b4d9797..248744b4d086 100644 >>>>>> --- a/arch/loongarch/kvm/Kconfig >>>>>> +++ b/arch/loongarch/kvm/Kconfig >>>>>> @@ -29,6 +29,7 @@ config KVM >>>>>> select KVM_MMIO >>>>>> select HAVE_KVM_READONLY_MEM >>>>>> select KVM_XFER_TO_GUEST_WORK >>>>>> + select SCHED_INFO >>>>>> help >>>>>> Support hosting virtualized guest machines using >>>>>> hardware virtualization extensions. You will need >>>>>> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c >>>>>> index c86e099af5ca..e2abd97fb13f 100644 >>>>>> --- a/arch/loongarch/kvm/exit.c >>>>>> +++ b/arch/loongarch/kvm/exit.c >>>>>> @@ -24,7 +24,7 @@ >>>>>> static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) >>>>>> { >>>>>> int rd, rj; >>>>>> - unsigned int index; >>>>>> + unsigned int index, ret; >>>>>> >>>>>> if (inst.reg2_format.opcode != cpucfg_op) >>>>>> return EMULATE_FAIL; >>>>>> @@ -50,7 +50,10 @@ static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) >>>>>> vcpu->arch.gprs[rd] = *(unsigned int *)KVM_SIGNATURE; >>>>>> break; >>>>>> case CPUCFG_KVM_FEATURE: >>>>>> - vcpu->arch.gprs[rd] = KVM_FEATURE_IPI; >>>>>> + ret = KVM_FEATURE_IPI; >>>>>> + if (sched_info_on()) >>>>> What about replacing it with your helper function kvm_pvtime_supported()? >>>> Sure, will replace it with helper function kvm_pvtime_supported(). >>> If you are sure this is the only issue, then needn't submit a new version. >> OK, thanks. >> >> By searching orginal submit of vcpu_is_preempt(), it can be located at >> https://lore.kernel.org/lkml/1477642287-24104-1-git-send-email-xinhui.pan@linux.vnet.ibm.com/ >> >> It is separated one, only that is depends on pv-spinlock and >> pv-stealtime. And there is no capability indicator for guest kernel, it >> is enabled by default. > Series applied with some modifications here, you can double-check the > correctness. > https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git/log/?h=loongarch-kvm Huacai, I download and test. The stealtime works for me. Regards Bibo Mao > > Huacai >> >> Regards >> Bibo Mao >> >>> >>> Huacai >>> >>>> >>>> Regards >>>> Bibo Mao >>>>> >>>>> Huacai >>>>> >>>>>> + ret |= KVM_FEATURE_STEAL_TIME; >>>>>> + vcpu->arch.gprs[rd] = ret; >>>>>> break; >>>>>> default: >>>>>> vcpu->arch.gprs[rd] = 0; >>>>>> @@ -687,6 +690,34 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu) >>>>>> return RESUME_GUEST; >>>>>> } >>>>>> >>>>>> +static long kvm_save_notify(struct kvm_vcpu *vcpu) >>>>>> +{ >>>>>> + unsigned long id, data; >>>>>> + >>>>>> + id = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); >>>>>> + data = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); >>>>>> + switch (id) { >>>>>> + case KVM_FEATURE_STEAL_TIME: >>>>>> + if (!kvm_pvtime_supported()) >>>>>> + return KVM_HCALL_INVALID_CODE; >>>>>> + >>>>>> + if (data & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) >>>>>> + return KVM_HCALL_INVALID_PARAMETER; >>>>>> + >>>>>> + vcpu->arch.st.guest_addr = data; >>>>>> + if (!(data & KVM_STEAL_PHYS_VALID)) >>>>>> + break; >>>>>> + >>>>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >>>>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >>>>>> + break; >>>>>> + default: >>>>>> + break; >>>>>> + }; >>>>>> + >>>>>> + return 0; >>>>>> +}; >>>>>> + >>>>>> /* >>>>>> * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root. >>>>>> * @vcpu: Virtual CPU context. >>>>>> @@ -758,6 +789,9 @@ static void kvm_handle_service(struct kvm_vcpu *vcpu) >>>>>> kvm_send_pv_ipi(vcpu); >>>>>> ret = KVM_HCALL_SUCCESS; >>>>>> break; >>>>>> + case KVM_HCALL_FUNC_NOTIFY: >>>>>> + ret = kvm_save_notify(vcpu); >>>>>> + break; >>>>>> default: >>>>>> ret = KVM_HCALL_INVALID_CODE; >>>>>> break; >>>>>> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c >>>>>> index 9e8030d45129..382796f1d3e6 100644 >>>>>> --- a/arch/loongarch/kvm/vcpu.c >>>>>> +++ b/arch/loongarch/kvm/vcpu.c >>>>>> @@ -31,6 +31,117 @@ const struct kvm_stats_header kvm_vcpu_stats_header = { >>>>>> sizeof(kvm_vcpu_stats_desc), >>>>>> }; >>>>>> >>>>>> +static void kvm_update_stolen_time(struct kvm_vcpu *vcpu) >>>>>> +{ >>>>>> + struct kvm_steal_time __user *st; >>>>>> + struct gfn_to_hva_cache *ghc; >>>>>> + struct kvm_memslots *slots; >>>>>> + gpa_t gpa; >>>>>> + u64 steal; >>>>>> + u32 version; >>>>>> + >>>>>> + ghc = &vcpu->arch.st.cache; >>>>>> + gpa = vcpu->arch.st.guest_addr; >>>>>> + if (!(gpa & KVM_STEAL_PHYS_VALID)) >>>>>> + return; >>>>>> + >>>>>> + gpa &= KVM_STEAL_PHYS_MASK; >>>>>> + slots = kvm_memslots(vcpu->kvm); >>>>>> + if (slots->generation != ghc->generation || gpa != ghc->gpa) { >>>>>> + if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, >>>>>> + sizeof(*st))) { >>>>>> + ghc->gpa = INVALID_GPA; >>>>>> + return; >>>>>> + } >>>>>> + } >>>>>> + >>>>>> + st = (struct kvm_steal_time __user *)ghc->hva; >>>>>> + unsafe_get_user(version, &st->version, out); >>>>>> + if (version & 1) >>>>>> + version += 1; >>>>>> + version += 1; >>>>>> + unsafe_put_user(version, &st->version, out); >>>>>> + smp_wmb(); >>>>>> + >>>>>> + unsafe_get_user(steal, &st->steal, out); >>>>>> + steal += current->sched_info.run_delay - >>>>>> + vcpu->arch.st.last_steal; >>>>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >>>>>> + unsafe_put_user(steal, &st->steal, out); >>>>>> + >>>>>> + smp_wmb(); >>>>>> + version += 1; >>>>>> + unsafe_put_user(version, &st->version, out); >>>>>> +out: >>>>>> + mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); >>>>>> +} >>>>>> + >>>>>> +static int kvm_loongarch_pvtime_has_attr(struct kvm_vcpu *vcpu, >>>>>> + struct kvm_device_attr *attr) >>>>>> +{ >>>>>> + if (!kvm_pvtime_supported() || >>>>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >>>>>> + return -ENXIO; >>>>>> + >>>>>> + return 0; >>>>>> +} >>>>>> + >>>>>> +static int kvm_loongarch_pvtime_get_attr(struct kvm_vcpu *vcpu, >>>>>> + struct kvm_device_attr *attr) >>>>>> +{ >>>>>> + u64 __user *user = (u64 __user *)attr->addr; >>>>>> + u64 gpa; >>>>>> + >>>>>> + if (!kvm_pvtime_supported() || >>>>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >>>>>> + return -ENXIO; >>>>>> + >>>>>> + gpa = vcpu->arch.st.guest_addr; >>>>>> + if (put_user(gpa, user)) >>>>>> + return -EFAULT; >>>>>> + >>>>>> + return 0; >>>>>> +} >>>>>> + >>>>>> +static int kvm_loongarch_pvtime_set_attr(struct kvm_vcpu *vcpu, >>>>>> + struct kvm_device_attr *attr) >>>>>> +{ >>>>>> + u64 __user *user = (u64 __user *)attr->addr; >>>>>> + struct kvm *kvm = vcpu->kvm; >>>>>> + u64 gpa; >>>>>> + int ret = 0; >>>>>> + int idx; >>>>>> + >>>>>> + if (!kvm_pvtime_supported() || >>>>>> + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) >>>>>> + return -ENXIO; >>>>>> + >>>>>> + if (get_user(gpa, user)) >>>>>> + return -EFAULT; >>>>>> + >>>>>> + if (gpa & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) >>>>>> + return -EINVAL; >>>>>> + >>>>>> + if (!(gpa & KVM_STEAL_PHYS_VALID)) { >>>>>> + vcpu->arch.st.guest_addr = gpa; >>>>>> + return 0; >>>>>> + } >>>>>> + >>>>>> + /* Check the address is in a valid memslot */ >>>>>> + idx = srcu_read_lock(&kvm->srcu); >>>>>> + if (kvm_is_error_hva(gfn_to_hva(kvm, gpa >> PAGE_SHIFT))) >>>>>> + ret = -EINVAL; >>>>>> + srcu_read_unlock(&kvm->srcu, idx); >>>>>> + >>>>>> + if (!ret) { >>>>>> + vcpu->arch.st.guest_addr = gpa; >>>>>> + vcpu->arch.st.last_steal = current->sched_info.run_delay; >>>>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >>>>>> + } >>>>>> + >>>>>> + return ret; >>>>>> +} >>>>>> + >>>>>> /* >>>>>> * kvm_check_requests - check and handle pending vCPU requests >>>>>> * >>>>>> @@ -48,6 +159,9 @@ static int kvm_check_requests(struct kvm_vcpu *vcpu) >>>>>> if (kvm_dirty_ring_check_request(vcpu)) >>>>>> return RESUME_HOST; >>>>>> >>>>>> + if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) >>>>>> + kvm_update_stolen_time(vcpu); >>>>>> + >>>>>> return RESUME_GUEST; >>>>>> } >>>>>> >>>>>> @@ -671,6 +785,9 @@ static int kvm_loongarch_vcpu_has_attr(struct kvm_vcpu *vcpu, >>>>>> case KVM_LOONGARCH_VCPU_CPUCFG: >>>>>> ret = kvm_loongarch_cpucfg_has_attr(vcpu, attr); >>>>>> break; >>>>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >>>>>> + ret = kvm_loongarch_pvtime_has_attr(vcpu, attr); >>>>>> + break; >>>>>> default: >>>>>> break; >>>>>> } >>>>>> @@ -703,6 +820,9 @@ static int kvm_loongarch_vcpu_get_attr(struct kvm_vcpu *vcpu, >>>>>> case KVM_LOONGARCH_VCPU_CPUCFG: >>>>>> ret = kvm_loongarch_get_cpucfg_attr(vcpu, attr); >>>>>> break; >>>>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >>>>>> + ret = kvm_loongarch_pvtime_get_attr(vcpu, attr); >>>>>> + break; >>>>>> default: >>>>>> break; >>>>>> } >>>>>> @@ -725,6 +845,9 @@ static int kvm_loongarch_vcpu_set_attr(struct kvm_vcpu *vcpu, >>>>>> case KVM_LOONGARCH_VCPU_CPUCFG: >>>>>> ret = kvm_loongarch_cpucfg_set_attr(vcpu, attr); >>>>>> break; >>>>>> + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: >>>>>> + ret = kvm_loongarch_pvtime_set_attr(vcpu, attr); >>>>>> + break; >>>>>> default: >>>>>> break; >>>>>> } >>>>>> @@ -1084,6 +1207,7 @@ static int _kvm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) >>>>>> >>>>>> /* Control guest page CCA attribute */ >>>>>> change_csr_gcfg(CSR_GCFG_MATC_MASK, CSR_GCFG_MATC_ROOT); >>>>>> + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); >>>>>> >>>>>> /* Don't bother restoring registers multiple times unless necessary */ >>>>>> if (vcpu->arch.aux_inuse & KVM_LARCH_HWCSR_USABLE) >>>>>> -- >>>>>> 2.39.3 >>>>>> >>>> >> >>
diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h index c87b6ea0ec47..2eb2f7572023 100644 --- a/arch/loongarch/include/asm/kvm_host.h +++ b/arch/loongarch/include/asm/kvm_host.h @@ -30,6 +30,7 @@ #define KVM_PRIVATE_MEM_SLOTS 0 #define KVM_HALT_POLL_NS_DEFAULT 500000 +#define KVM_REQ_STEAL_UPDATE KVM_ARCH_REQ(1) #define KVM_GUESTDBG_SW_BP_MASK \ (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) @@ -201,6 +202,12 @@ struct kvm_vcpu_arch { struct kvm_mp_state mp_state; /* cpucfg */ u32 cpucfg[KVM_MAX_CPUCFG_REGS]; + /* paravirt steal time */ + struct { + u64 guest_addr; + u64 last_steal; + struct gfn_to_hva_cache cache; + } st; }; static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg) diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h index 4ba2312e5f8c..a9ba8185d4af 100644 --- a/arch/loongarch/include/asm/kvm_para.h +++ b/arch/loongarch/include/asm/kvm_para.h @@ -14,6 +14,7 @@ #define KVM_HCALL_SERVICE HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SERVICE) #define KVM_HCALL_FUNC_IPI 1 +#define KVM_HCALL_FUNC_NOTIFY 2 #define KVM_HCALL_SWDBG HYPERCALL_ENCODE(HYPERVISOR_KVM, KVM_HCALL_CODE_SWDBG) @@ -24,6 +25,15 @@ #define KVM_HCALL_INVALID_CODE -1UL #define KVM_HCALL_INVALID_PARAMETER -2UL +#define KVM_STEAL_PHYS_VALID BIT_ULL(0) +#define KVM_STEAL_PHYS_MASK GENMASK_ULL(63, 6) +struct kvm_steal_time { + __u64 steal; + __u32 version; + __u32 flags; + __u32 pad[12]; +}; + /* * Hypercall interface for KVM hypervisor * diff --git a/arch/loongarch/include/asm/kvm_vcpu.h b/arch/loongarch/include/asm/kvm_vcpu.h index 590a92cb5416..d7e51300a89f 100644 --- a/arch/loongarch/include/asm/kvm_vcpu.h +++ b/arch/loongarch/include/asm/kvm_vcpu.h @@ -120,4 +120,8 @@ static inline void kvm_write_reg(struct kvm_vcpu *vcpu, int num, unsigned long v vcpu->arch.gprs[num] = val; } +static inline bool kvm_pvtime_supported(void) +{ + return !!sched_info_on(); +} #endif /* __ASM_LOONGARCH_KVM_VCPU_H__ */ diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h index eb09adda54b7..7a4633ef284b 100644 --- a/arch/loongarch/include/asm/loongarch.h +++ b/arch/loongarch/include/asm/loongarch.h @@ -169,6 +169,7 @@ #define KVM_SIGNATURE "KVM\0" #define CPUCFG_KVM_FEATURE (CPUCFG_KVM_BASE + 4) #define KVM_FEATURE_IPI BIT(1) +#define KVM_FEATURE_STEAL_TIME BIT(2) #ifndef __ASSEMBLY__ diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h index f9abef382317..ddc5cab0ffd0 100644 --- a/arch/loongarch/include/uapi/asm/kvm.h +++ b/arch/loongarch/include/uapi/asm/kvm.h @@ -81,7 +81,11 @@ struct kvm_fpu { #define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT)) #define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG) #define KVM_IOC_CPUCFG(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CPUCFG, REG) + +/* Device Control API on vcpu fd */ #define KVM_LOONGARCH_VCPU_CPUCFG 0 +#define KVM_LOONGARCH_VCPU_PVTIME_CTRL 1 +#define KVM_LOONGARCH_VCPU_PVTIME_GPA 0 struct kvm_debug_exit_arch { }; diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig index c4ef2b4d9797..248744b4d086 100644 --- a/arch/loongarch/kvm/Kconfig +++ b/arch/loongarch/kvm/Kconfig @@ -29,6 +29,7 @@ config KVM select KVM_MMIO select HAVE_KVM_READONLY_MEM select KVM_XFER_TO_GUEST_WORK + select SCHED_INFO help Support hosting virtualized guest machines using hardware virtualization extensions. You will need diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c index c86e099af5ca..e2abd97fb13f 100644 --- a/arch/loongarch/kvm/exit.c +++ b/arch/loongarch/kvm/exit.c @@ -24,7 +24,7 @@ static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) { int rd, rj; - unsigned int index; + unsigned int index, ret; if (inst.reg2_format.opcode != cpucfg_op) return EMULATE_FAIL; @@ -50,7 +50,10 @@ static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) vcpu->arch.gprs[rd] = *(unsigned int *)KVM_SIGNATURE; break; case CPUCFG_KVM_FEATURE: - vcpu->arch.gprs[rd] = KVM_FEATURE_IPI; + ret = KVM_FEATURE_IPI; + if (sched_info_on()) + ret |= KVM_FEATURE_STEAL_TIME; + vcpu->arch.gprs[rd] = ret; break; default: vcpu->arch.gprs[rd] = 0; @@ -687,6 +690,34 @@ static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu) return RESUME_GUEST; } +static long kvm_save_notify(struct kvm_vcpu *vcpu) +{ + unsigned long id, data; + + id = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); + data = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); + switch (id) { + case KVM_FEATURE_STEAL_TIME: + if (!kvm_pvtime_supported()) + return KVM_HCALL_INVALID_CODE; + + if (data & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) + return KVM_HCALL_INVALID_PARAMETER; + + vcpu->arch.st.guest_addr = data; + if (!(data & KVM_STEAL_PHYS_VALID)) + break; + + vcpu->arch.st.last_steal = current->sched_info.run_delay; + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); + break; + default: + break; + }; + + return 0; +}; + /* * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root. * @vcpu: Virtual CPU context. @@ -758,6 +789,9 @@ static void kvm_handle_service(struct kvm_vcpu *vcpu) kvm_send_pv_ipi(vcpu); ret = KVM_HCALL_SUCCESS; break; + case KVM_HCALL_FUNC_NOTIFY: + ret = kvm_save_notify(vcpu); + break; default: ret = KVM_HCALL_INVALID_CODE; break; diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c index 9e8030d45129..382796f1d3e6 100644 --- a/arch/loongarch/kvm/vcpu.c +++ b/arch/loongarch/kvm/vcpu.c @@ -31,6 +31,117 @@ const struct kvm_stats_header kvm_vcpu_stats_header = { sizeof(kvm_vcpu_stats_desc), }; +static void kvm_update_stolen_time(struct kvm_vcpu *vcpu) +{ + struct kvm_steal_time __user *st; + struct gfn_to_hva_cache *ghc; + struct kvm_memslots *slots; + gpa_t gpa; + u64 steal; + u32 version; + + ghc = &vcpu->arch.st.cache; + gpa = vcpu->arch.st.guest_addr; + if (!(gpa & KVM_STEAL_PHYS_VALID)) + return; + + gpa &= KVM_STEAL_PHYS_MASK; + slots = kvm_memslots(vcpu->kvm); + if (slots->generation != ghc->generation || gpa != ghc->gpa) { + if (kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, gpa, + sizeof(*st))) { + ghc->gpa = INVALID_GPA; + return; + } + } + + st = (struct kvm_steal_time __user *)ghc->hva; + unsafe_get_user(version, &st->version, out); + if (version & 1) + version += 1; + version += 1; + unsafe_put_user(version, &st->version, out); + smp_wmb(); + + unsafe_get_user(steal, &st->steal, out); + steal += current->sched_info.run_delay - + vcpu->arch.st.last_steal; + vcpu->arch.st.last_steal = current->sched_info.run_delay; + unsafe_put_user(steal, &st->steal, out); + + smp_wmb(); + version += 1; + unsafe_put_user(version, &st->version, out); +out: + mark_page_dirty_in_slot(vcpu->kvm, ghc->memslot, gpa_to_gfn(ghc->gpa)); +} + +static int kvm_loongarch_pvtime_has_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + if (!kvm_pvtime_supported() || + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) + return -ENXIO; + + return 0; +} + +static int kvm_loongarch_pvtime_get_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + u64 __user *user = (u64 __user *)attr->addr; + u64 gpa; + + if (!kvm_pvtime_supported() || + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) + return -ENXIO; + + gpa = vcpu->arch.st.guest_addr; + if (put_user(gpa, user)) + return -EFAULT; + + return 0; +} + +static int kvm_loongarch_pvtime_set_attr(struct kvm_vcpu *vcpu, + struct kvm_device_attr *attr) +{ + u64 __user *user = (u64 __user *)attr->addr; + struct kvm *kvm = vcpu->kvm; + u64 gpa; + int ret = 0; + int idx; + + if (!kvm_pvtime_supported() || + attr->attr != KVM_LOONGARCH_VCPU_PVTIME_GPA) + return -ENXIO; + + if (get_user(gpa, user)) + return -EFAULT; + + if (gpa & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) + return -EINVAL; + + if (!(gpa & KVM_STEAL_PHYS_VALID)) { + vcpu->arch.st.guest_addr = gpa; + return 0; + } + + /* Check the address is in a valid memslot */ + idx = srcu_read_lock(&kvm->srcu); + if (kvm_is_error_hva(gfn_to_hva(kvm, gpa >> PAGE_SHIFT))) + ret = -EINVAL; + srcu_read_unlock(&kvm->srcu, idx); + + if (!ret) { + vcpu->arch.st.guest_addr = gpa; + vcpu->arch.st.last_steal = current->sched_info.run_delay; + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); + } + + return ret; +} + /* * kvm_check_requests - check and handle pending vCPU requests * @@ -48,6 +159,9 @@ static int kvm_check_requests(struct kvm_vcpu *vcpu) if (kvm_dirty_ring_check_request(vcpu)) return RESUME_HOST; + if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) + kvm_update_stolen_time(vcpu); + return RESUME_GUEST; } @@ -671,6 +785,9 @@ static int kvm_loongarch_vcpu_has_attr(struct kvm_vcpu *vcpu, case KVM_LOONGARCH_VCPU_CPUCFG: ret = kvm_loongarch_cpucfg_has_attr(vcpu, attr); break; + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: + ret = kvm_loongarch_pvtime_has_attr(vcpu, attr); + break; default: break; } @@ -703,6 +820,9 @@ static int kvm_loongarch_vcpu_get_attr(struct kvm_vcpu *vcpu, case KVM_LOONGARCH_VCPU_CPUCFG: ret = kvm_loongarch_get_cpucfg_attr(vcpu, attr); break; + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: + ret = kvm_loongarch_pvtime_get_attr(vcpu, attr); + break; default: break; } @@ -725,6 +845,9 @@ static int kvm_loongarch_vcpu_set_attr(struct kvm_vcpu *vcpu, case KVM_LOONGARCH_VCPU_CPUCFG: ret = kvm_loongarch_cpucfg_set_attr(vcpu, attr); break; + case KVM_LOONGARCH_VCPU_PVTIME_CTRL: + ret = kvm_loongarch_pvtime_set_attr(vcpu, attr); + break; default: break; } @@ -1084,6 +1207,7 @@ static int _kvm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) /* Control guest page CCA attribute */ change_csr_gcfg(CSR_GCFG_MATC_MASK, CSR_GCFG_MATC_ROOT); + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); /* Don't bother restoring registers multiple times unless necessary */ if (vcpu->arch.aux_inuse & KVM_LARCH_HWCSR_USABLE)
Steal time feature is added here in kvm side, VM can search supported features provided by KVM hypervisor, feature KVM_FEATURE_STEAL_TIME is added here. Like x86, steal time structure is saved in guest memory, one hypercall function KVM_HCALL_FUNC_NOTIFY is added to notify KVM to enable the feature. One cpu attr ioctl command KVM_LOONGARCH_VCPU_PVTIME_CTRL is added to save and restore base address of steal time structure when VM is migrated. Signed-off-by: Bibo Mao <maobibo@loongson.cn> --- arch/loongarch/include/asm/kvm_host.h | 7 ++ arch/loongarch/include/asm/kvm_para.h | 10 ++ arch/loongarch/include/asm/kvm_vcpu.h | 4 + arch/loongarch/include/asm/loongarch.h | 1 + arch/loongarch/include/uapi/asm/kvm.h | 4 + arch/loongarch/kvm/Kconfig | 1 + arch/loongarch/kvm/exit.c | 38 +++++++- arch/loongarch/kvm/vcpu.c | 124 +++++++++++++++++++++++++ 8 files changed, 187 insertions(+), 2 deletions(-)