From: Joerg Roedel <[email protected]> To benefit from IOTLB flushes on other CPUs we have to free the already flushed IOVAs from the ring-buffer before we do the queue_ring_full() check.
Signed-off-by: Joerg Roedel <[email protected]> --- drivers/iommu/amd_iommu.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 623ab53..34a6cac 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -1883,14 +1883,20 @@ static void queue_add(struct dma_ops_domain *dom, spin_lock_irqsave(&queue->lock, flags); /* + * First remove the enries from the ring-buffer that are already + * flushed to make the below queue_ring_full() check less likely + */ + queue_ring_free_flushed(dom, queue); + + /* * When ring-queue is full, flush the entries from the IOTLB so * that we can free all entries with queue_ring_free_flushed() * below. */ - if (queue_ring_full(queue)) + if (queue_ring_full(queue)) { dma_ops_domain_flush_tlb(dom); - - queue_ring_free_flushed(dom, queue); + queue_ring_free_flushed(dom, queue); + } idx = queue_ring_add(queue); -- 2.7.4
