[PATCH] KVM: stats: Add VM stat for remote tlb flush requests
From: Jing Zhang <hidden>
Date: 2021-08-17 00:27:01
Also in:
kvmarm
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine (kvm), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Paolo Bonzini, Marc Zyngier, Oliver Upton, Linus Torvalds
Add a new stat that counts the number of times a remote TLB flush is requested, regardless of whether it kicks vCPUs out of guest mode. This allows us to look at how often flushes are initiated. Original-by: David Matlack [off-list ref] Signed-off-by: Jing Zhang <redacted> --- arch/arm64/kvm/mmu.c | 1 + include/linux/kvm_host.h | 3 ++- include/linux/kvm_types.h | 1 + virt/kvm/kvm_main.c | 1 + 4 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 0625bf2353c2..f5bb235bbb59 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c@@ -80,6 +80,7 @@ static bool memslot_is_logging(struct kvm_memory_slot *memslot) */ void kvm_flush_remote_tlbs(struct kvm *kvm) { + ++kvm->stat.generic.remote_tlb_flush_requests; kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu); }
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index d447b21cdd73..27cb69e564cb 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h@@ -1444,7 +1444,8 @@ struct _kvm_stats_desc { KVM_STATS_BASE_POW10, -9, sz) #define KVM_GENERIC_VM_STATS() \ - STATS_DESC_COUNTER(VM_GENERIC, remote_tlb_flush) + STATS_DESC_COUNTER(VM_GENERIC, remote_tlb_flush), \ + STATS_DESC_COUNTER(VM_GENERIC, remote_tlb_flush_requests) #define KVM_GENERIC_VCPU_STATS() \ STATS_DESC_COUNTER(VCPU_GENERIC, halt_successful_poll), \
diff --git a/include/linux/kvm_types.h b/include/linux/kvm_types.h
index de7fb5f364d8..2237abb93ccd 100644
--- a/include/linux/kvm_types.h
+++ b/include/linux/kvm_types.h@@ -80,6 +80,7 @@ struct kvm_mmu_memory_cache { struct kvm_vm_stat_generic { u64 remote_tlb_flush; + u64 remote_tlb_flush_requests; }; struct kvm_vcpu_stat_generic {
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 3e67c93ca403..26b77ab98a04 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c@@ -318,6 +318,7 @@ void kvm_flush_remote_tlbs(struct kvm *kvm) */ long dirty_count = smp_load_acquire(&kvm->tlbs_dirty); + ++kvm->stat.generic.remote_tlb_flush_requests; /* * We want to publish modifications to the page tables before reading * mode. Pairs with a memory barrier in arch-specific code.
base-commit: a3e0b8bd99ab098514bde2434301fa6fde040da2 -- 2.33.0.rc1.237.g0d66db33f3-goog