From f85e2cb5dbaf905e9470d3fe099b31619da431fc Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Thu, 24 Nov 2011 17:41:54 +0800 Subject: KVM: introduce a table to map slot id to index in memslots array The operation of getting dirty log is frequent when framebuffer-based displays are used(for example, Xwindow), so, we introduce a mapping table to speed up id_to_memslot() Signed-off-by: Xiao Guangrong Signed-off-by: Avi Kivity --- include/linux/kvm_host.h | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'include/linux/kvm_host.h') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 9efdf5c703a5..8c5c30361b0d 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -239,6 +239,8 @@ struct kvm_irq_routing_table {}; struct kvm_memslots { u64 generation; struct kvm_memory_slot memslots[KVM_MEM_SLOTS_NUM]; + /* The mapping table from slot id to the index in memslots[]. */ + int id_to_index[KVM_MEM_SLOTS_NUM]; }; struct kvm { @@ -341,14 +343,13 @@ static inline struct kvm_memslots *kvm_memslots(struct kvm *kvm) static inline struct kvm_memory_slot * id_to_memslot(struct kvm_memslots *slots, int id) { - int i; + int index = slots->id_to_index[id]; + struct kvm_memory_slot *slot; - for (i = 0; i < KVM_MEM_SLOTS_NUM; i++) - if (slots->memslots[i].id == id) - return &slots->memslots[i]; + slot = &slots->memslots[index]; - WARN_ON(1); - return NULL; + WARN_ON(slot->id != id); + return slot; } #define HPA_MSB ((sizeof(hpa_t) * 8) - 1) -- cgit v1.2.3