iommu/amd: Implement timeout to flush unmap queues
In case the queue doesn't fill up, we flush the TLB at least
10ms after the unmap happened to make sure that the TLB is
cleaned up.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index a8e4c5a..c0b2f4f 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -105,6 +105,9 @@
DEFINE_PER_CPU(struct flush_queue, flush_queue);
+static atomic_t queue_timer_on;
+static struct timer_list queue_timer;
+
/*
* Domain for untranslated devices - only allocated
* if iommu=pt passed on kernel cmd line.
@@ -2151,6 +2154,24 @@
queue->next = 0;
}
+void queue_flush_timeout(unsigned long unsused)
+{
+ int cpu;
+
+ atomic_set(&queue_timer_on, 0);
+
+ for_each_possible_cpu(cpu) {
+ struct flush_queue *queue;
+ unsigned long flags;
+
+ queue = per_cpu_ptr(&flush_queue, cpu);
+ spin_lock_irqsave(&queue->lock, flags);
+ if (queue->next > 0)
+ __queue_flush(queue);
+ spin_unlock_irqrestore(&queue->lock, flags);
+ }
+}
+
static void queue_add(struct dma_ops_domain *dma_dom,
unsigned long address, unsigned long pages)
{
@@ -2176,6 +2197,10 @@
entry->dma_dom = dma_dom;
spin_unlock_irqrestore(&queue->lock, flags);
+
+ if (atomic_cmpxchg(&queue_timer_on, 0, 1) == 0)
+ mod_timer(&queue_timer, jiffies + msecs_to_jiffies(10));
+
put_cpu_ptr(&flush_queue);
}
@@ -2634,6 +2659,9 @@
int __init amd_iommu_init_dma_ops(void)
{
+ setup_timer(&queue_timer, queue_flush_timeout, 0);
+ atomic_set(&queue_timer_on, 0);
+
swiotlb = iommu_pass_through ? 1 : 0;
iommu_detected = 1;