[PATCH v4 02/15] KVM: async_pf: Add helper function to check completion queue
From: Gavin Shan <hidden>
Date: 2021-08-15 01:01:51
Also in:
kvmarm, lkml
Subsystem:
kernel virtual machine (kvm), kernel virtual machine for x86 (kvm/x86), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Paolo Bonzini, Sean Christopherson, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
This adds inline helper kvm_check_async_pf_completion_queue() to check if there are pending completion in the queue. The empty stub is also added on !CONFIG_KVM_ASYNC_PF so that the caller needn't consider if CONFIG_KVM_ASYNC_PF is enabled. All checks on the completion queue is done by the newly added inline function since list_empty() and list_empty_careful() are interchangeable. Signed-off-by: Gavin Shan <redacted> --- arch/x86/kvm/x86.c | 2 +- include/linux/kvm_host.h | 10 ++++++++++ virt/kvm/async_pf.c | 10 +++++----- virt/kvm/kvm_main.c | 4 +--- 4 files changed, 17 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e5d5c5ed7dd4..7f35d9324b99 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c@@ -11591,7 +11591,7 @@ static inline bool kvm_guest_apic_has_interrupt(struct kvm_vcpu *vcpu) static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu) { - if (!list_empty_careful(&vcpu->async_pf.done)) + if (kvm_check_async_pf_completion_queue(vcpu)) return true; if (kvm_apic_has_events(vcpu))
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 85b61a456f1c..a5f990f6dc35 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h@@ -339,12 +339,22 @@ struct kvm_async_pf { bool notpresent_injected; }; +static inline bool kvm_check_async_pf_completion_queue(struct kvm_vcpu *vcpu) +{ + return !list_empty_careful(&vcpu->async_pf.done); +} + void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu); void kvm_check_async_pf_completion(struct kvm_vcpu *vcpu); bool kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, unsigned long hva, struct kvm_arch_async_pf *arch); int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu); #else +static inline bool kvm_check_async_pf_completion_queue(struct kvm_vcpu *vcpu) +{ + return false; +} + static inline void kvm_check_async_pf_completion(struct kvm_vcpu *vcpu) { } #endif
diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c
index dd777688d14a..d145a61a046a 100644
--- a/virt/kvm/async_pf.c
+++ b/virt/kvm/async_pf.c@@ -70,7 +70,7 @@ static void async_pf_execute(struct work_struct *work) kvm_arch_async_page_present(vcpu, apf); spin_lock(&vcpu->async_pf.lock); - first = list_empty(&vcpu->async_pf.done); + first = !kvm_check_async_pf_completion_queue(vcpu); list_add_tail(&apf->link, &vcpu->async_pf.done); apf->vcpu = NULL; spin_unlock(&vcpu->async_pf.lock);
@@ -122,7 +122,7 @@ void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu) spin_lock(&vcpu->async_pf.lock); } - while (!list_empty(&vcpu->async_pf.done)) { + while (kvm_check_async_pf_completion_queue(vcpu)) { struct kvm_async_pf *work = list_first_entry(&vcpu->async_pf.done, typeof(*work), link);
@@ -138,7 +138,7 @@ void kvm_check_async_pf_completion(struct kvm_vcpu *vcpu) { struct kvm_async_pf *work; - while (!list_empty_careful(&vcpu->async_pf.done) && + while (kvm_check_async_pf_completion_queue(vcpu) && kvm_arch_can_dequeue_async_page_present(vcpu)) { spin_lock(&vcpu->async_pf.lock); work = list_first_entry(&vcpu->async_pf.done, typeof(*work),
@@ -205,7 +205,7 @@ int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu) struct kvm_async_pf *work; bool first; - if (!list_empty_careful(&vcpu->async_pf.done)) + if (kvm_check_async_pf_completion_queue(vcpu)) return 0; work = kmem_cache_zalloc(async_pf_cache, GFP_ATOMIC);
@@ -216,7 +216,7 @@ int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu) INIT_LIST_HEAD(&work->queue); /* for list_del to work */ spin_lock(&vcpu->async_pf.lock); - first = list_empty(&vcpu->async_pf.done); + first = !kvm_check_async_pf_completion_queue(vcpu); list_add_tail(&work->link, &vcpu->async_pf.done); spin_unlock(&vcpu->async_pf.lock);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index b50dbe269f4b..8795503651b1 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c@@ -3282,10 +3282,8 @@ static bool vcpu_dy_runnable(struct kvm_vcpu *vcpu) if (kvm_arch_dy_runnable(vcpu)) return true; -#ifdef CONFIG_KVM_ASYNC_PF - if (!list_empty_careful(&vcpu->async_pf.done)) + if (kvm_check_async_pf_completion_queue(vcpu)) return true; -#endif return false; }
--
2.23.0