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 <eesposit@xxxxxxxxxx>
---
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
