Instead of sending a single ioctl every time ->region_* or ->log_* callbacks are called, "queue" all memory regions in a kvm_userspace_memory_region_list that will be sent only when committing.
This allow the KVM kernel API to be extended and support multiple memslots updates in a single call. Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com> --- accel/kvm/kvm-all.c | 131 ++++++++++++++++++++++++++------------- include/sysemu/kvm_int.h | 8 +++ 2 files changed, 96 insertions(+), 43 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index e9947ec18b..9780f3d2da 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -357,56 +357,50 @@ int kvm_physical_memory_addr_from_host(KVMState *s, void *ram, return ret; } +static struct kvm_userspace_memory_region_entry *kvm_memory_region_entry_get( + KVMMemoryListener *kml) +{ + struct MemoryRegionNodeArray *arr = &kml->mem_array; + struct kvm_userspace_memory_region_list *list = arr->list; + + if (list->nent == arr->max_entries) { + arr->max_entries += DEFAULT_KVM_MEMORY_REGION_ARRAY_GROW; + list = g_realloc(list, + sizeof(struct kvm_userspace_memory_region_list) + + arr->max_entries * + sizeof(struct kvm_userspace_memory_region_entry)); + } + + return &list->entries[list->nent++]; +} + static int kvm_set_user_memory_region(KVMMemoryListener *kml, KVMSlot *slot, bool new) { - KVMState *s = kvm_state; - struct kvm_userspace_memory_region_entry mem; - int ret; + struct kvm_userspace_memory_region_entry *mem; + + mem = kvm_memory_region_entry_get(kml); + + mem->slot = slot->slot | (kml->as_id << 16); + mem->guest_phys_addr = slot->start_addr; + mem->userspace_addr = (unsigned long)slot->ram; + mem->flags = slot->flags; - mem.slot = slot->slot | (kml->as_id << 16); - mem.guest_phys_addr = slot->start_addr; - mem.userspace_addr = (unsigned long)slot->ram; - mem.flags = slot->flags; + if (slot->memory_size && !new && (mem->flags ^ slot->old_flags) & + KVM_MEM_READONLY) { + struct kvm_userspace_memory_region_entry *mem2 = mem; - if (slot->memory_size && !new && (mem.flags ^ slot->old_flags) & KVM_MEM_READONLY) { + mem = kvm_memory_region_entry_get(kml); + memcpy(mem, mem2, sizeof(struct kvm_userspace_memory_region_entry)); /* Set the slot size to 0 before setting the slot to the desired * value. This is needed based on KVM commit 75d61fbc. */ - mem.memory_size = 0; - mem.invalidate_slot = 1; - /* - * Note that mem is struct kvm_userspace_memory_region_entry, while the - * kernel expects a kvm_userspace_memory_region, so it will currently - * ignore mem->invalidate_slot and mem->padding. - */ - ret = kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem); - if (ret < 0) { - goto err; - } + mem2->memory_size = 0; + mem2->invalidate_slot = 1; } - mem.memory_size = slot->memory_size; - /* - * Invalidate if it's a kvm memslot MOVE or DELETE operation, but - * currently QEMU does not perform any memslot MOVE operation. - */ - mem.invalidate_slot = slot->memory_size == 0; + mem->memory_size = slot->memory_size; + mem->invalidate_slot = slot->memory_size == 0; - /* - * Note that mem is struct kvm_userspace_memory_region_entry, while the - * kernel expects a kvm_userspace_memory_region, so it will currently - * ignore mem->invalidate_slot and mem->padding. - */ - ret = kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem); - slot->old_flags = mem.flags; -err: - trace_kvm_set_user_memory(mem.slot, mem.flags, mem.guest_phys_addr, - mem.memory_size, mem.userspace_addr, ret); - if (ret < 0) { - error_report("%s: KVM_SET_USER_MEMORY_REGION failed, slot=%d," - " start=0x%" PRIx64 ", size=0x%" PRIx64 ": %s", - __func__, mem.slot, slot->start_addr, - (uint64_t)mem.memory_size, strerror(errno)); - } - return ret; + slot->old_flags = mem->flags; + return 0; } static int do_kvm_destroy_vcpu(CPUState *cpu) @@ -1534,12 +1528,54 @@ static void kvm_region_add(MemoryListener *listener, static void kvm_region_del(MemoryListener *listener, MemoryRegionSection *section) { - KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener); + KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, + listener); kvm_set_phys_mem(kml, section, false); memory_region_unref(section->mr); } +static void kvm_begin(MemoryListener *listener) +{ + KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, + listener); + assert(kml->mem_array.list->nent == 0); +} + +static void kvm_commit(MemoryListener *listener) +{ + KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, + listener); + KVMState *s = kvm_state; + int i; + + for (i = 0; i < kml->mem_array.list->nent; i++) { + struct kvm_userspace_memory_region_entry *mem; + int ret; + + mem = &kml->mem_array.list->entries[i]; + + /* + * Note that mem is struct kvm_userspace_memory_region_entry, while the + * kernel expects a kvm_userspace_memory_region, so it will currently + * ignore mem->invalidate_slot and mem->padding. + */ + ret = kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, mem); + + trace_kvm_set_user_memory(mem->slot, mem->flags, mem->guest_phys_addr, + mem->memory_size, mem->userspace_addr, 0); + + if (ret < 0) { + error_report("%s: KVM_SET_USER_MEMORY_REGION failed, slot=%d," + " start=0x%" PRIx64 ": %s", + __func__, mem->slot, + (uint64_t)mem->memory_size, strerror(errno)); + } + } + + kml->mem_array.list->nent = 0; +} + static void kvm_log_sync(MemoryListener *listener, MemoryRegionSection *section) { @@ -1681,8 +1717,16 @@ void kvm_memory_listener_register(KVMState *s, KVMMemoryListener *kml, kml->slots[i].slot = i; } + kml->mem_array.max_entries = DEFAULT_KVM_MEMORY_REGION_ARRAY_GROW; + kml->mem_array.list = g_malloc0( + sizeof(struct kvm_userspace_memory_region_list) + + sizeof(struct kvm_userspace_memory_region_entry) * + kml->mem_array.max_entries); + kml->listener.region_add = kvm_region_add; kml->listener.region_del = kvm_region_del; + kml->listener.begin = kvm_begin; + kml->listener.commit = kvm_commit; kml->listener.log_start = kvm_log_start; kml->listener.log_stop = kvm_log_stop; kml->listener.priority = 10; @@ -2691,6 +2735,7 @@ err: close(s->fd); } g_free(s->memory_listener.slots); + g_free(s->memory_listener.mem_array.list); return ret; } diff --git a/include/sysemu/kvm_int.h b/include/sysemu/kvm_int.h index 1f5487d9b7..1adc1c8722 100644 --- a/include/sysemu/kvm_int.h +++ b/include/sysemu/kvm_int.h @@ -30,9 +30,17 @@ typedef struct KVMSlot ram_addr_t ram_start_offset; } KVMSlot; +#define DEFAULT_KVM_MEMORY_REGION_ARRAY_GROW 10 + +struct MemoryRegionNodeArray { + struct kvm_userspace_memory_region_list *list; + int max_entries; +}; + typedef struct KVMMemoryListener { MemoryListener listener; KVMSlot *slots; + struct MemoryRegionNodeArray mem_array; int as_id; } KVMMemoryListener; -- 2.31.1