KVM caches per-vCPU host task's run_delay in per-architecture struct kvm_vcpu_arch at last_steal. Move the cache to struct kvm_vcpu and convert x86, arm64, riscv, and loongarch to use the common field. Add HAVE_KVM_PV_STEAL_TIME so last_steal is used only for architectures that implement KVM stealtime. Suggested-by: Marc Zyngier Signed-off-by: Dongli Zhang --- Marc suggested reusing CONFIG_HAVE_PV_STEAL_CLOCK_GEN, but I introduced HAVE_KVM_PV_STEAL_TIME instead. As I have access to only x86 and arm64 KVM hosts, I created and validated the selftest on those two architectures only. arch/arm64/include/asm/kvm_host.h | 1 - arch/arm64/kvm/Kconfig | 1 + arch/arm64/kvm/pvtime.c | 8 ++++---- arch/loongarch/include/asm/kvm_host.h | 1 - arch/loongarch/kvm/Kconfig | 1 + arch/loongarch/kvm/exit.c | 2 +- arch/loongarch/kvm/vcpu.c | 6 +++--- arch/riscv/include/asm/kvm_host.h | 1 - arch/riscv/kvm/Kconfig | 1 + arch/riscv/kvm/vcpu_sbi_sta.c | 10 +++++----- arch/x86/include/asm/kvm_host.h | 1 - arch/x86/kvm/Kconfig | 1 + arch/x86/kvm/x86.c | 5 ++--- include/linux/kvm_host.h | 4 ++++ virt/kvm/Kconfig | 3 +++ 15 files changed, 26 insertions(+), 20 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 27fe0cd5b2d7..36cb7dee988c 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -937,7 +937,6 @@ struct kvm_vcpu_arch { /* Guest PV state */ struct { - u64 last_steal; gpa_t base; } steal; diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 449154f9a485..f5855bfc681c 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -34,6 +34,7 @@ menuconfig KVM select HAVE_KVM_IRQ_BYPASS select HAVE_KVM_READONLY_MEM select HAVE_KVM_VCPU_RUN_PID_CHANGE + select HAVE_KVM_PV_STEAL_TIME select SCHED_INFO select GUEST_PERF_EVENTS if PERF_EVENTS select KVM_GUEST_MEMFD diff --git a/arch/arm64/kvm/pvtime.c b/arch/arm64/kvm/pvtime.c index 4ceabaa4c30b..a67d93845d79 100644 --- a/arch/arm64/kvm/pvtime.c +++ b/arch/arm64/kvm/pvtime.c @@ -14,7 +14,7 @@ void kvm_update_stolen_time(struct kvm_vcpu *vcpu) { struct kvm *kvm = vcpu->kvm; u64 base = vcpu->arch.steal.base; - u64 last_steal = vcpu->arch.steal.last_steal; + u64 last_steal = vcpu->last_steal; u64 offset = offsetof(struct pvclock_vcpu_stolen_time, stolen_time); u64 steal = 0; int idx; @@ -25,8 +25,8 @@ void kvm_update_stolen_time(struct kvm_vcpu *vcpu) idx = srcu_read_lock(&kvm->srcu); if (!kvm_get_guest(kvm, base + offset, steal)) { steal = le64_to_cpu(steal); - vcpu->arch.steal.last_steal = READ_ONCE(current->sched_info.run_delay); - steal += vcpu->arch.steal.last_steal - last_steal; + vcpu->last_steal = READ_ONCE(current->sched_info.run_delay); + steal += vcpu->last_steal - last_steal; kvm_put_guest(kvm, base + offset, cpu_to_le64(steal)); } srcu_read_unlock(&kvm->srcu, idx); @@ -61,7 +61,7 @@ gpa_t kvm_init_stolen_time(struct kvm_vcpu *vcpu) * Start counting stolen time from the time the guest requests * the feature enabled. */ - vcpu->arch.steal.last_steal = current->sched_info.run_delay; + vcpu->last_steal = current->sched_info.run_delay; kvm_write_guest_lock(kvm, base, &init_values, sizeof(init_values)); return base; diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h index 23cfbecebbd7..14514a25b261 100644 --- a/arch/loongarch/include/asm/kvm_host.h +++ b/arch/loongarch/include/asm/kvm_host.h @@ -253,7 +253,6 @@ struct kvm_vcpu_arch { /* paravirt steal time */ struct { u64 guest_addr; - u64 last_steal; struct gfn_to_hva_cache cache; u8 preempted; } st; diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig index 15da2d88c0c1..4996ec9c07f9 100644 --- a/arch/loongarch/kvm/Kconfig +++ b/arch/loongarch/kvm/Kconfig @@ -26,6 +26,7 @@ config KVM select HAVE_KVM_MSI select HAVE_KVM_READONLY_MEM select KVM_COMMON + select HAVE_KVM_PV_STEAL_TIME select KVM_GENERIC_DIRTYLOG_READ_PROTECT select KVM_GENERIC_HARDWARE_ENABLING select KVM_MMIO diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c index 4f58e6e2cf86..56ae6b18f8c1 100644 --- a/arch/loongarch/kvm/exit.c +++ b/arch/loongarch/kvm/exit.c @@ -773,7 +773,7 @@ static long kvm_save_notify(struct kvm_vcpu *vcpu) if (!(data & KVM_STEAL_PHYS_VALID)) return 0; - vcpu->arch.st.last_steal = current->sched_info.run_delay; + vcpu->last_steal = current->sched_info.run_delay; kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); return 0; default: diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c index ed9e092c97ba..728d29eba8e0 100644 --- a/arch/loongarch/kvm/vcpu.c +++ b/arch/loongarch/kvm/vcpu.c @@ -187,8 +187,8 @@ static void kvm_update_stolen_time(struct kvm_vcpu *vcpu) 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; + steal += current->sched_info.run_delay - vcpu->last_steal; + vcpu->last_steal = current->sched_info.run_delay; unsafe_put_user(steal, &st->steal, out); smp_wmb(); @@ -1205,7 +1205,7 @@ static int kvm_loongarch_pvtime_set_attr(struct kvm_vcpu *vcpu, if (!ret) { vcpu->arch.st.guest_addr = gpa; - vcpu->arch.st.last_steal = current->sched_info.run_delay; + vcpu->last_steal = current->sched_info.run_delay; kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); } diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h index a30600579231..305875301c04 100644 --- a/arch/riscv/include/asm/kvm_host.h +++ b/arch/riscv/include/asm/kvm_host.h @@ -273,7 +273,6 @@ struct kvm_vcpu_arch { /* SBI steal-time accounting */ struct { gpa_t shmem; - u64 last_steal; } sta; }; diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig index ec2cee0a39e0..1ff07a904a02 100644 --- a/arch/riscv/kvm/Kconfig +++ b/arch/riscv/kvm/Kconfig @@ -26,6 +26,7 @@ config KVM select HAVE_KVM_READONLY_MEM select HAVE_KVM_DIRTY_RING_ACQ_REL select KVM_COMMON + select HAVE_KVM_PV_STEAL_TIME select KVM_GENERIC_DIRTYLOG_READ_PROTECT select KVM_GENERIC_HARDWARE_ENABLING select KVM_MMIO diff --git a/arch/riscv/kvm/vcpu_sbi_sta.c b/arch/riscv/kvm/vcpu_sbi_sta.c index 60e50296a008..9a77d3bde7c7 100644 --- a/arch/riscv/kvm/vcpu_sbi_sta.c +++ b/arch/riscv/kvm/vcpu_sbi_sta.c @@ -19,13 +19,13 @@ static void kvm_riscv_vcpu_sbi_sta_reset(struct kvm_vcpu *vcpu) { vcpu->arch.sta.shmem = INVALID_GPA; - vcpu->arch.sta.last_steal = 0; + vcpu->last_steal = 0; } void kvm_riscv_vcpu_record_steal_time(struct kvm_vcpu *vcpu) { gpa_t shmem = vcpu->arch.sta.shmem; - u64 last_steal = vcpu->arch.sta.last_steal; + u64 last_steal = vcpu->last_steal; __le32 __user *sequence_ptr; __le64 __user *steal_ptr; __le32 sequence_le; @@ -67,8 +67,8 @@ void kvm_riscv_vcpu_record_steal_time(struct kvm_vcpu *vcpu) if (!WARN_ON(get_user(steal_le, steal_ptr))) { steal = le64_to_cpu(steal_le); - vcpu->arch.sta.last_steal = READ_ONCE(current->sched_info.run_delay); - steal += vcpu->arch.sta.last_steal - last_steal; + vcpu->last_steal = READ_ONCE(current->sched_info.run_delay); + steal += vcpu->last_steal - last_steal; WARN_ON(put_user(cpu_to_le64(steal), steal_ptr)); } @@ -115,7 +115,7 @@ static int kvm_sbi_sta_steal_time_set_shmem(struct kvm_vcpu *vcpu) return SBI_ERR_INVALID_ADDRESS; vcpu->arch.sta.shmem = shmem; - vcpu->arch.sta.last_steal = current->sched_info.run_delay; + vcpu->last_steal = current->sched_info.run_delay; return 0; } diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 683bb8bf43a9..ebdd8526ae12 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -872,7 +872,6 @@ struct kvm_vcpu_arch { struct { u8 preempted; u64 msr_val; - u64 last_steal; struct gfn_to_hva_cache cache; } st; diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 538ed1e80332..b2aea8058841 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -40,6 +40,7 @@ config KVM_X86 select HAVE_KVM_MSI select HAVE_KVM_CPU_RELAX_INTERCEPT select HAVE_KVM_NO_POLL + select HAVE_KVM_PV_STEAL_TIME select VIRT_XFER_TO_GUEST_WORK select KVM_GENERIC_DIRTYLOG_READ_PROTECT select KVM_VFIO diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 79468ddfe473..927c8b1ed83d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2129,9 +2129,8 @@ static void record_steal_time(struct kvm_vcpu *vcpu) 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; + steal += current->sched_info.run_delay - vcpu->last_steal; + vcpu->last_steal = current->sched_info.run_delay; unsafe_put_user(steal, &st->steal, out); version += 1; diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 03bfc92864b6..ff9d423b6a7c 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -398,6 +398,10 @@ struct kvm_vcpu { */ struct kvm_memory_slot *last_used_slot; u64 last_used_slot_gen; + +#ifdef CONFIG_HAVE_KVM_PV_STEAL_TIME + u64 last_steal; +#endif }; /* diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig index c3c0ee253fc7..f42a3a0fc5ba 100644 --- a/virt/kvm/Kconfig +++ b/virt/kvm/Kconfig @@ -82,6 +82,9 @@ config HAVE_KVM_IRQ_BYPASS config HAVE_KVM_VCPU_RUN_PID_CHANGE bool +config HAVE_KVM_PV_STEAL_TIME + bool + config HAVE_KVM_NO_POLL bool -- 2.43.7