From 6caa5812e2d126a0aa8a17816c1ba6f0a0c2b309 Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Mon, 2 Aug 2021 19:28:09 +0000 Subject: KVM: arm64: Use generic KVM xfer to guest work function Clean up handling of checks for pending work by switching to the generic infrastructure to do so. We pick up handling for TIF_NOTIFY_RESUME from this switch, meaning that task work will be correctly handled. Signed-off-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20210802192809.1851010-4-oupton@google.com --- arch/arm64/kvm/Kconfig | 1 + arch/arm64/kvm/arm.c | 72 ++++++++++++++++++++++++++++++-------------------- 2 files changed, 45 insertions(+), 28 deletions(-) (limited to 'arch/arm64') diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index a4eba0908bfa..8bc1fac5fa26 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -26,6 +26,7 @@ menuconfig KVM select HAVE_KVM_ARCH_TLB_FLUSH_ALL select KVM_MMIO select KVM_GENERIC_DIRTYLOG_READ_PROTECT + select KVM_XFER_TO_GUEST_WORK select SRCU select KVM_VFIO select HAVE_KVM_EVENTFD diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 60d0a546d7fd..8245efc6e88f 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -6,6 +6,7 @@ #include #include +#include #include #include #include @@ -714,6 +715,45 @@ static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) static_branch_unlikely(&arm64_mismatched_32bit_el0); } +/** + * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest + * @vcpu: The VCPU pointer + * @ret: Pointer to write optional return code + * + * Returns: true if the VCPU needs to return to a preemptible + interruptible + * and skip guest entry. + * + * This function disambiguates between two different types of exits: exits to a + * preemptible + interruptible kernel context and exits to userspace. For an + * exit to userspace, this function will write the return code to ret and return + * true. For an exit to preemptible + interruptible kernel context (i.e. check + * for pending work and re-enter), return true without writing to ret. + */ +static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) +{ + struct kvm_run *run = vcpu->run; + + /* + * If we're using a userspace irqchip, then check if we need + * to tell a userspace irqchip about timer or PMU level + * changes and if so, exit to userspace (the actual level + * state gets updated in kvm_timer_update_run and + * kvm_pmu_update_run below). + */ + if (static_branch_unlikely(&userspace_irqchip_in_use)) { + if (kvm_timer_should_notify_user(vcpu) || + kvm_pmu_should_notify_user(vcpu)) { + *ret = -EINTR; + run->exit_reason = KVM_EXIT_INTR; + return true; + } + } + + return kvm_request_pending(vcpu) || + need_new_vmid_gen(&vcpu->arch.hw_mmu->vmid) || + xfer_to_guest_mode_work_pending(); +} + /** * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code * @vcpu: The VCPU pointer @@ -757,7 +797,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) /* * Check conditions before entering the guest */ - cond_resched(); + ret = xfer_to_guest_mode_handle_work(vcpu); + if (!ret) + ret = 1; update_vmid(&vcpu->arch.hw_mmu->vmid); @@ -776,31 +818,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) kvm_vgic_flush_hwstate(vcpu); - /* - * Exit if we have a signal pending so that we can deliver the - * signal to user space. - */ - if (signal_pending(current)) { - ret = -EINTR; - run->exit_reason = KVM_EXIT_INTR; - ++vcpu->stat.signal_exits; - } - - /* - * If we're using a userspace irqchip, then check if we need - * to tell a userspace irqchip about timer or PMU level - * changes and if so, exit to userspace (the actual level - * state gets updated in kvm_timer_update_run and - * kvm_pmu_update_run below). - */ - if (static_branch_unlikely(&userspace_irqchip_in_use)) { - if (kvm_timer_should_notify_user(vcpu) || - kvm_pmu_should_notify_user(vcpu)) { - ret = -EINTR; - run->exit_reason = KVM_EXIT_INTR; - } - } - /* * Ensure we set mode to IN_GUEST_MODE after we disable * interrupts and before the final VCPU requests check. @@ -809,8 +826,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) */ smp_store_mb(vcpu->mode, IN_GUEST_MODE); - if (ret <= 0 || need_new_vmid_gen(&vcpu->arch.hw_mmu->vmid) || - kvm_request_pending(vcpu)) { + if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { vcpu->mode = OUTSIDE_GUEST_MODE; isb(); /* Ensure work in x_flush_hwstate is committed */ kvm_pmu_sync_hwstate(vcpu); -- cgit v1.2.3