diff options
Diffstat (limited to 'include/linux/kvm_host.h')
| -rw-r--r-- | include/linux/kvm_host.h | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 2f80ce84fbcf..79db70a8323e 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -29,6 +29,7 @@ #include <linux/refcount.h> #include <linux/nospec.h> #include <linux/notifier.h> +#include <linux/hashtable.h> #include <linux/xarray.h> #include <asm/signal.h> @@ -426,6 +427,7 @@ static inline int kvm_vcpu_exiting_guest_mode(struct kvm_vcpu *vcpu) #define KVM_MEM_MAX_NR_PAGES ((1UL << 31) - 1) struct kvm_memory_slot { + struct hlist_node id_node; gfn_t base_gfn; unsigned long npages; unsigned long *dirty_bitmap; @@ -527,8 +529,15 @@ static inline int kvm_arch_vcpu_memslots_id(struct kvm_vcpu *vcpu) */ struct kvm_memslots { u64 generation; - /* The mapping table from slot id to the index in memslots[]. */ - short id_to_index[KVM_MEM_SLOTS_NUM]; + /* + * The mapping table from slot id to the index in memslots[]. + * + * 7-bit bucket count matches the size of the old id to index array for + * 512 slots, while giving good performance with this slot count. + * Higher bucket counts bring only small performance improvements but + * always result in higher memory usage (even for lower memslot counts). + */ + DECLARE_HASHTABLE(id_hash, 7); atomic_t last_used_slot; int used_slots; struct kvm_memory_slot memslots[]; @@ -796,16 +805,14 @@ static inline struct kvm_memslots *kvm_vcpu_memslots(struct kvm_vcpu *vcpu) static inline struct kvm_memory_slot *id_to_memslot(struct kvm_memslots *slots, int id) { - int index = slots->id_to_index[id]; struct kvm_memory_slot *slot; - if (index < 0) - return NULL; - - slot = &slots->memslots[index]; + hash_for_each_possible(slots->id_hash, slot, id_node, id) { + if (slot->id == id) + return slot; + } - WARN_ON(slot->id != id); - return slot; + return NULL; } /* |