From patchwork Mon Aug 13 18:19:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Myron Stowe X-Patchwork-Id: 957137 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 41q3sh4FSxz9s4V for ; Tue, 14 Aug 2018 04:19:36 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729025AbeHMVCy (ORCPT ); Mon, 13 Aug 2018 17:02:54 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:45634 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728821AbeHMVCy (ORCPT ); Mon, 13 Aug 2018 17:02:54 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 976637D84D; Mon, 13 Aug 2018 18:19:34 +0000 (UTC) Received: from tak.stowe (ovpn-120-77.rdu2.redhat.com [10.10.120.77]) by smtp.corp.redhat.com (Postfix) with ESMTP id 33AC51C70A; Mon, 13 Aug 2018 18:19:32 +0000 (UTC) Subject: [PATCH 0/2] Augment device matching its upstream Root Port's MPS logic From: Myron Stowe To: bhelgaas@google.com, linux-pci@vger.kernel.org Cc: keith.busch@intel.com, jdmason@kudzu.us, okaya@kernel.org Date: Mon, 13 Aug 2018 12:19:31 -0600 Message-ID: <20180813181931.105655.22182.stgit@tak.stowe> User-Agent: StGit/0.18 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Mon, 13 Aug 2018 18:19:34 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Mon, 13 Aug 2018 18:19:34 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'myron.stowe@redhat.com' RCPT:'' Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org In commit 27d868b5e6cf ("PCI: Set MPS to match upstream bridge") Keith made sure every device's MPS setting matched its upstream bridge, making it more likely that a hot-added devices would work in a system with an optimized MPS configuration. This series augments Keith's approach to include tuning down a Root Port's MPS setting in the case where a hot-added device is not capable of matching it (see: [1]). Testing by Dongdong exposed a bug with the logic including Virtual Functions (VFs). VFs should not be included so a pre-cursor patch, 1/2, was added to cover such. [1] https://bugzilla.kernel.org/show_bug.cgi?id=200527 Myron Stowe (2): PCI: Skip MPS logic for Virtual Functions (VFs) PCI: Match Root Port's MPS to endpoint's MPSS as necessary drivers/pci/probe.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-)