From f1600e549b948a32ad7672e069b2915314637ae3 Mon Sep 17 00:00:00 2001 From: Sowmini Varadhan Date: Thu, 12 Mar 2015 20:02:36 -0400 Subject: sparc: Make sparc64 use scalable lib/iommu-common.c functions In iperf experiments running linux as the Tx side (TCP client) with 10 threads results in a severe performance drop when TSO is disabled, indicating a weakness in the software that can be avoided by using the scalable IOMMU arena DMA allocation. Baseline numbers before this patch: with default settings (TSO enabled) : 9-9.5 Gbps Disable TSO using ethtool- drops badly: 2-3 Gbps. After this patch, iperf client with 10 threads, can give a throughput of at least 8.5 Gbps, even when TSO is disabled. Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller --- arch/sparc/kernel/iommu_common.h | 8 -------- 1 file changed, 8 deletions(-) (limited to 'arch/sparc/kernel/iommu_common.h') diff --git a/arch/sparc/kernel/iommu_common.h b/arch/sparc/kernel/iommu_common.h index 1ec0de4156e7..f4be0d724fc6 100644 --- a/arch/sparc/kernel/iommu_common.h +++ b/arch/sparc/kernel/iommu_common.h @@ -48,12 +48,4 @@ static inline int is_span_boundary(unsigned long entry, return iommu_is_span_boundary(entry, nr, shift, boundary_size); } -unsigned long iommu_range_alloc(struct device *dev, - struct iommu *iommu, - unsigned long npages, - unsigned long *handle); -void iommu_range_free(struct iommu *iommu, - dma_addr_t dma_addr, - unsigned long npages); - #endif /* _IOMMU_COMMON_H */ -- cgit v1.2.3-59-g8ed1b