vdpa: commit all host notifier MRs in a single MR transaction

This allows the vhost-vdpa device to batch the setup of all its MRs of
host notifiers.

This significantly reduces the device starting time, e.g. the time spend
on setup the host notifier MRs reduce from 423ms to 32ms for a VM with
64 vCPUs and 3 vhost-vDPA generic devices (vdpa_sim_blk, 64vq per device).

Signed-off-by: Longpeng <longpeng2@huawei.com>
Message-Id: <20221227072015.3134-4-longpeng2@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
This commit is contained in:
Longpeng 2022-12-27 15:20:15 +08:00 committed by Michael S. Tsirkin
parent 0fdc6b8509
commit e66f2311d6

View File

@ -519,9 +519,18 @@ static void vhost_vdpa_host_notifiers_uninit(struct vhost_dev *dev, int n)
{
int i;
/*
* Pack all the changes to the memory regions in a single
* transaction to avoid a few updating of the address space
* topology.
*/
memory_region_transaction_begin();
for (i = dev->vq_index; i < dev->vq_index + n; i++) {
vhost_vdpa_host_notifier_uninit(dev, i);
}
memory_region_transaction_commit();
}
static void vhost_vdpa_host_notifiers_init(struct vhost_dev *dev)
@ -534,17 +543,21 @@ static void vhost_vdpa_host_notifiers_init(struct vhost_dev *dev)
return;
}
/*
* Pack all the changes to the memory regions in a single
* transaction to avoid a few updating of the address space
* topology.
*/
memory_region_transaction_begin();
for (i = dev->vq_index; i < dev->vq_index + dev->nvqs; i++) {
if (vhost_vdpa_host_notifier_init(dev, i)) {
goto err;
vhost_vdpa_host_notifiers_uninit(dev, i - dev->vq_index);
break;
}
}
return;
err:
vhost_vdpa_host_notifiers_uninit(dev, i - dev->vq_index);
return;
memory_region_transaction_commit();
}
static void vhost_vdpa_svq_cleanup(struct vhost_dev *dev)