From f1600e549b948a32ad7672e069b2915314637ae3 Mon Sep 17 00:00:00 2001 From: Sowmini Varadhan Date: Thu, 12 Mar 2015 20:02:36 -0400 Subject: [PATCH] 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 --- Reading git-format-patch failed