KVMMemoryListener *ml;
AddressSpace *as;
} *as;
+ uint64_t kvm_dirty_ring_bytes; /* Size of the per-vcpu dirty ring */
+ uint32_t kvm_dirty_ring_size; /* Number of dirty GFNs per ring */
};
KVMState *kvm_state;
return kvm_state->kernel_irqchip_split == ON_OFF_AUTO_ON;
}
+static void kvm_get_dirty_ring_size(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ KVMState *s = KVM_STATE(obj);
+ uint32_t value = s->kvm_dirty_ring_size;
+
+ visit_type_uint32(v, name, &value, errp);
+}
+
+static void kvm_set_dirty_ring_size(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ KVMState *s = KVM_STATE(obj);
+ Error *error = NULL;
+ uint32_t value;
+
+ if (s->fd != -1) {
+ error_setg(errp, "Cannot set properties after the accelerator has been initialized");
+ return;
+ }
+
+ visit_type_uint32(v, name, &value, &error);
+ if (error) {
+ error_propagate(errp, error);
+ return;
+ }
+ if (value & (value - 1)) {
+ error_setg(errp, "dirty-ring-size must be a power of two.");
+ return;
+ }
+
+ s->kvm_dirty_ring_size = value;
+}
+
static void kvm_accel_instance_init(Object *obj)
{
KVMState *s = KVM_STATE(obj);
s->kvm_shadow_mem = -1;
s->kernel_irqchip_allowed = true;
s->kernel_irqchip_split = ON_OFF_AUTO_AUTO;
+ /* KVM dirty ring is by default off */
+ s->kvm_dirty_ring_size = 0;
}
static void kvm_accel_class_init(ObjectClass *oc, void *data)
NULL, NULL);
object_class_property_set_description(oc, "kvm-shadow-mem",
"KVM shadow MMU size");
+
+ object_class_property_add(oc, "dirty-ring-size", "uint32",
+ kvm_get_dirty_ring_size, kvm_set_dirty_ring_size,
+ NULL, NULL);
+ object_class_property_set_description(oc, "dirty-ring-size",
+ "Size of KVM dirty page ring buffer (default: 0, i.e. use bitmap)");
}
static const TypeInfo kvm_accel_type = {
" kvm-shadow-mem=size of KVM shadow MMU in bytes\n"
" split-wx=on|off (enable TCG split w^x mapping)\n"
" tb-size=n (TCG translation block cache size)\n"
+ " dirty-ring-size=n (KVM dirty ring GFN count, default 0)\n"
" thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL)
SRST
``-accel name[,prop=value[,...]]``
where both the back-end and front-ends support it and no
incompatible TCG features have been enabled (e.g.
icount/replay).
+
+ ``dirty-ring-size=n``
+ When the KVM accelerator is used, it controls the size of the per-vCPU
+ dirty page ring buffer (number of entries for each vCPU). It should
+ be a value that is power of two, and it should be 1024 or bigger (but
+ still less than the maximum value that the kernel supports). 4096
+ could be a good initial value if you have no idea which is the best.
+ Set this value to 0 to disable the feature. By default, this feature
+ is disabled (dirty-ring-size=0). When enabled, KVM will instead
+ record dirty pages in a bitmap.
+
ERST
DEF("smp", HAS_ARG, QEMU_OPTION_smp,