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 <oup...@google.com>
---
arch/arm64/kvm/Kconfig | 1 +
arch/arm64/kvm/arm.c | 72 ++++++++++++++++++++++++++----------------
2 files changed, 45 insertions(+), 28 deletions(-)
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 <linux/bug.h>
#include <linux/cpu_pm.h>
+#include <linux/entry-kvm.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
@@ -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);
--
2.32.0.554.ge1b32706d8-goog
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