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 alex@modula-shop-systems.de Signed-off-by: Bart Van Assche bart.vanassche@wdc.com Cc: Alexander Schmid alex@modula-shop-systems.de Cc: stable@vger.kernel.org --- 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 b48843833d69..241c0e72dce3 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -3871,12 +3871,10 @@ 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) {
On Mon, Feb 12, 2018 at 09:50:25AM -0800, Bart Van Assche wrote:
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 alex@modula-shop-systems.de Signed-off-by: Bart Van Assche bart.vanassche@wdc.com Cc: Alexander Schmid alex@modula-shop-systems.de Cc: stable@vger.kernel.org drivers/infiniband/ulp/srp/ib_srp.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
Applied to for-next
Thanks, Jason
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