e85a7b20ffcefd5360e2542460737ecc15c author Anton Blanchard 1338752582 +0000 committer Benjamin Herrenschmidt 1341288887 +1000 powerpc/iommu: Reduce spinlock coverage in iommu_alloc and iommu_free We currently hold the IOMMU spinlock around tce_build and tce_flush. This causes our spinlock hold times to be much higher than required and can impact multiqueue adapters. This patch moves tce_build and tce_flush outside of the lock in iommu_alloc, and tce_flush outside of the lock in iommu_free. Some performance numbers were obtained with a Chelsio T3 adapter on two POWER7 boxes, running a 100 session TCP round robin test. Performance improved 32% with this patch applied. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt ) 6§ç †xœ