Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967061AbcKXPgt (ORCPT ); Thu, 24 Nov 2016 10:36:49 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:58402 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966963AbcKXPcl (ORCPT ); Thu, 24 Nov 2016 10:32:41 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Jurgens , Maor Gottlieb , Leon Romanovsky , Doug Ledford Subject: [PATCH 4.8 57/67] IB/mlx5: Use cache line size to select CQE stride Date: Thu, 24 Nov 2016 16:27:51 +0100 Message-Id: <20161124145500.255650911@linuxfoundation.org> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20161124145457.061710350@linuxfoundation.org> References: <20161124145457.061710350@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1359 Lines: 41 4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Jurgens commit 16b0e0695a73b68d8ca40288c8f9614ef208917b upstream. When creating kernel CQs use 128B CQE stride if the cache line size is 128B, 64B otherwise. This prevents multiple CQEs from residing in a 128B cache line, which can cause retries when there are concurrent read and writes in one cache line. Tested with IPoIB on PPC64, saw ~5% throughput improvement. Fixes: e126ba97dba9 ('mlx5: Add driver for Mellanox Connect-IB adapters') Signed-off-by: Daniel Jurgens Signed-off-by: Maor Gottlieb Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/mlx5/cq.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/infiniband/hw/mlx5/cq.c +++ b/drivers/infiniband/hw/mlx5/cq.c @@ -917,8 +917,7 @@ struct ib_cq *mlx5_ib_create_cq(struct i if (err) goto err_create; } else { - /* for now choose 64 bytes till we have a proper interface */ - cqe_size = 64; + cqe_size = cache_line_size() == 128 ? 128 : 64; err = create_cq_kernel(dev, cq, entries, cqe_size, &cqb, &index, &inlen); if (err)