From: Joerg Roedel <joerg.roedel@amd.com>
Date: Fri, 22 May 2009 10:27:53 +0000 (+0200)
Subject: amd-iommu: disable round-robin allocator for CONFIG_IOMMU_STRESS
X-Git-Tag: archive/raspbian/4.9.13-1+rpi1~10^2~22064^2~13^4~2
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/www.github.com/%22bookmarks:///%22http:/www.example.com/cgi/%22https:/www.github.com/%22bookmarks:/?a=commitdiff_plain;h=fe16f088a88fb73161bba8784375c829f7e87b54;p=linux-4.9.git

amd-iommu: disable round-robin allocator for CONFIG_IOMMU_STRESS

Disabling the round-robin allocator results in reusing the same
dma-addresses again very fast. This is a good test if the iotlb flushing
is working correctly.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 31d56c36010a..543822b39a84 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -783,6 +783,11 @@ static unsigned long dma_ops_alloc_addresses(struct device *dev,
 {
 	unsigned long address;
 
+#ifdef CONFIG_IOMMU_STRESS
+	dom->next_address = 0;
+	dom->need_flush = true;
+#endif
+
 	address = dma_ops_area_alloc(dev, dom, pages, align_mask,
 				     dma_mask, dom->next_address);