[PATCH v5 2/4] KVM: mmu: add a helper to account memory used by KVM MMU.

[Yosry Ahmed <yosryahmed@google.com>]

Add a helper to account pages used by KVM for page tables in secondary
pagetable stats. This function will be used by subsequent patches in
different archs.

Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
---
 include/linux/kvm_host.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 883e86ec8e8c4..645585f3a4bed 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -2246,6 +2246,15 @@ static inline void kvm_handle_signal_exit(struct kvm_vcpu *vcpu)
 }
 #endif /* CONFIG_KVM_XFER_TO_GUEST_WORK */
 
+/*
+ * If nr > 1, we assume virt is the address of the first page of a block of
+ * pages that were allocated together (i.e accounted together).
+ */
+static inline void kvm_account_pgtable_pages(void *virt, int nr)
+{
+	mod_lruvec_page_state(virt_to_page(virt), NR_SECONDARY_PAGETABLE, nr);
+}
+
 /*
  * This defines how many reserved entries we want to keep before we
  * kick the vcpu to the userspace to avoid dirty ring full.  This
-- 
2.36.1.255.ge46751e96f-goog