[PATCH v3 4/4] iommu/vt-d: Remove redundant IOTLB flush

Lu Baolu
2020-04-22T08:09:40Z

IOTLB flush already included in the PASID tear down and the page request
drain process. There is no need to flush again.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/iommu/intel-svm.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index 2534641ef707..543109fe2003 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -212,7 +212,6 @@ static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm)
list_for_each_entry_rcu(sdev, &svm->devs, list) {
intel_pasid_tear_down_entry(svm->iommu, sdev->dev, svm->pasid);
intel_svm_drain_prq(sdev->dev, svm->pasid);
- intel_flush_svm_range_dev(svm, sdev, 0, -1, 0);
}
rcu_read_unlock();

@@ -406,7 +405,6 @@ int intel_svm_unbind_gpasid(struct device *dev, int pasid)
list_del_rcu(&sdev->list);
intel_pasid_tear_down_entry(iommu, dev, svm->pasid);
intel_svm_drain_prq(dev, svm->pasid);
- intel_flush_svm_range_dev(svm, sdev, 0, -1, 0);
kfree_rcu(sdev, rcu);

if (list_empty(&svm->devs)) {
@@ -645,7 +643,6 @@ int intel_svm_unbind_mm(struct device *dev, int pasid)
* hard to be as defensive as we might like. */
intel_pasid_tear_down_entry(iommu, dev, svm->pasid);
intel_svm_drain_prq(dev, svm->pasid);
- intel_flush_svm_range_dev(svm, sdev, 0, -1, 0);
kfree_rcu(sdev, rcu);

if (list_empty(&svm->devs)) {
--
2.17.1