[PATCH 3.12 099/111] iommu/amd: Optimize alloc_new_range for new fetch_pte interface

From: Jiri Slaby
Date: Wed Jun 10 2015 - 11:47:00 EST


From: Joerg Roedel <jroedel@xxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 5d7c94c3f4f20964b217d64ee44a9a08320c315a upstream.

Now that fetch_pte returns the page-size of the pte, the
call in this function can also be optimized a little bit.

Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@xxxxxxx>
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/iommu/amd_iommu.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 8f6344df7c49..9e91d8c38a1e 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1642,7 +1642,7 @@ static int alloc_new_range(struct dma_ops_domain *dma_dom,
{
int index = dma_dom->aperture_size >> APERTURE_RANGE_SHIFT;
struct amd_iommu *iommu;
- unsigned long i, old_size;
+ unsigned long i, old_size, pte_pgsize;

#ifdef CONFIG_IOMMU_STRESS
populate = false;
@@ -1715,13 +1715,13 @@ static int alloc_new_range(struct dma_ops_domain *dma_dom,
*/
for (i = dma_dom->aperture[index]->offset;
i < dma_dom->aperture_size;
- i += PAGE_SIZE) {
- unsigned long pte_pgsize;
+ i += pte_pgsize) {
u64 *pte = fetch_pte(&dma_dom->domain, i, &pte_pgsize);
if (!pte || !IOMMU_PTE_PRESENT(*pte))
continue;

- dma_ops_reserve_addresses(dma_dom, i >> PAGE_SHIFT, 1);
+ dma_ops_reserve_addresses(dma_dom, i >> PAGE_SHIFT,
+ pte_pgsize >> 12);
}

update_domain(&dma_dom->domain);
--
2.4.2

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