[PATCH 18/22] AMD IOMMU: add stats counter for cross-page request

[Joerg Roedel]

Impact: see number of requests for more than one page in debugfs

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
 arch/x86/kernel/amd_iommu.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index a00d20c..02e8c18 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -70,6 +70,7 @@ DECLARE_STATS_COUNTER(cnt_map_sg);
 DECLARE_STATS_COUNTER(cnt_unmap_sg);
 DECLARE_STATS_COUNTER(cnt_alloc_coherent);
 DECLARE_STATS_COUNTER(cnt_free_coherent);
+DECLARE_STATS_COUNTER(cross_page);
 
 static struct dentry *stats_dir;
 static struct dentry *de_isolate;
@@ -103,6 +104,7 @@ static void amd_iommu_stats_init(void)
 	amd_iommu_stats_add(&cnt_unmap_sg);
 	amd_iommu_stats_add(&cnt_alloc_coherent);
 	amd_iommu_stats_add(&cnt_free_coherent);
+	amd_iommu_stats_add(&cross_page);
 }
 
 #endif
@@ -1216,6 +1218,9 @@ static dma_addr_t __map_single(struct device *dev,
 	pages = iommu_num_pages(paddr, size, PAGE_SIZE);
 	paddr &= PAGE_MASK;
 
+	if (pages > 1)
+		INC_STATS_COUNTER(cross_page);
+
 	if (align)
 		align_mask = (1UL << get_order(size)) - 1;
 
-- 
1.5.6.4


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