This improves performance in case of netperf with vhost-net:
* TCP_STREAM: From 1374.81Mbit/s to 1845Mbit/s (37%)
* TCP_RR: From 6559.36 trans/s to 7916.29/s (21%)
* UDP_RR: From 6705.39 trans/s to 8199.39/s (22%)
* UDP_STREAM: No change observed (not significant 0.1% improvement)
Signed-off-by: Eugenio Pérez <epere...@redhat.com>
---
hw/i386/intel_iommu.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 2ad6b9d796..d539a9f281 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -1959,6 +1959,12 @@ static void vtd_iotlb_domain_invalidate(IntelIOMMUState
*s, uint16_t domain_id)
vtd_iommu_unlock(s);
QLIST_FOREACH(vtd_as, &s->vtd_as_with_notifiers, next) {
+ if (vtd_as->iommu.iommu_notify_flags & IOMMU_NOTIFIER_DEVIOTLB) {
+ /* If IOMMU memory region is DEVICE IOTLB type, it does not make
+ * sense to send regular IOMMU notifications. */
+ continue;
+ }
+
if (!vtd_dev_to_context_entry(s, pci_bus_num(vtd_as->bus),
vtd_as->devfn, &ce) &&
domain_id == vtd_get_domain_id(s, &ce)) {
--
2.18.1
