From 16757e775dd6db0fda7cf7da1eaa31d8e5a11ff1 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Mon, 12 Feb 2018 09:50:25 -0800 Subject: [PATCH] IB/srp: Fix completion vector assignment algorithm commit 3a148896b24adf8688dc0c59af54531931677a40 upstream. Ensure that cv_end is equal to ibdev->num_comp_vectors for the NUMA node with the highest index. This patch improves spreading of RDMA channels over completion vectors and thereby improves performance, especially on systems with only a single NUMA node. This patch drops support for the comp_vector login parameter by ignoring the value of that parameter since I have not found a good way to combine support for that parameter and automatic spreading of RDMA channels over completion vectors. Fixes: d92c0da71a35 ("IB/srp: Add multichannel support") Reported-by: Alexander Schmid Signed-off-by: Bart Van Assche Cc: Alexander Schmid Cc: stable@vger.kernel.org Signed-off-by: Jason Gunthorpe Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/ulp/srp/ib_srp.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index 245a59bab27c..463ea592a42a 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -3397,12 +3397,10 @@ static ssize_t srp_create_target(struct device *dev, num_online_nodes()); const int ch_end = ((node_idx + 1) * target->ch_count / num_online_nodes()); - const int cv_start = (node_idx * ibdev->num_comp_vectors / - num_online_nodes() + target->comp_vector) - % ibdev->num_comp_vectors; - const int cv_end = ((node_idx + 1) * ibdev->num_comp_vectors / - num_online_nodes() + target->comp_vector) - % ibdev->num_comp_vectors; + const int cv_start = node_idx * ibdev->num_comp_vectors / + num_online_nodes(); + const int cv_end = (node_idx + 1) * ibdev->num_comp_vectors / + num_online_nodes(); int cpu_idx = 0; for_each_online_cpu(cpu) { -- 2.20.1