From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50FC1C10F14 for ; Thu, 3 Oct 2019 17:25:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 31F1720865 for ; Thu, 3 Oct 2019 17:25:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731461AbfJCRZv (ORCPT ); Thu, 3 Oct 2019 13:25:51 -0400 Received: from mga04.intel.com ([192.55.52.120]:34645 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730428AbfJCRZs (ORCPT ); Thu, 3 Oct 2019 13:25:48 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Oct 2019 10:22:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,253,1566889200"; d="scan'208";a="191329490" Received: from linux.intel.com ([10.54.29.200]) by fmsmga008.fm.intel.com with ESMTP; 03 Oct 2019 10:22:44 -0700 Received: from [10.54.74.33] (skuppusw-desk.jf.intel.com [10.54.74.33]) by linux.intel.com (Postfix) with ESMTP id CC766580378; Thu, 3 Oct 2019 10:22:44 -0700 (PDT) Reply-To: sathyanarayanan.kuppuswamy@linux.intel.com Subject: Re: [PATCH v7 1/7] PCI/ATS: Fix pci_prg_resp_pasid_required() dependency issues To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, ashok.raj@intel.com, keith.busch@intel.com References: <20190905191854.GE103977@google.com> From: Kuppuswamy Sathyanarayanan Organization: Intel Message-ID: Date: Thu, 3 Oct 2019 10:20:24 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190905191854.GE103977@google.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Bjorn, Thanks for looking into this patch set. On 9/5/19 12:18 PM, Bjorn Helgaas wrote: > On Wed, Aug 28, 2019 at 03:14:01PM -0700, sathyanarayanan.kuppuswamy@linux.intel.com wrote: >> From: Kuppuswamy Sathyanarayanan >> >> Since pci_prg_resp_pasid_required() function has dependency on both >> PASID and PRI, define it only if both CONFIG_PCI_PRI and >> CONFIG_PCI_PASID config options are enabled. >> >> Fixes: e5567f5f6762 ("PCI/ATS: Add pci_prg_resp_pasid_required() >> interface.") > [Don't split tags, including "Fixes:" across lines] > > This definitely doesn't fix e5567f5f6762. That commit added > pci_prg_resp_pasid_required(), but with no dependency on > CONFIG_PCI_PRI or CONFIG_PCI_PASID. > > This patch is only required when a subsequent patch is applied. It > should be squashed into the commit that requires it so it's obvious > why it's needed. > > I've been poking at this series, and I'll post a v8 soon with this and > other fixes. In your v8 submission you did not merge this patch. You did not use pri_cap or pasid_cap cached values. Instead you have re-read the value from register. Is this intentional? Since this function will be called for every VF device we might loose some performance benefit. > >> Signed-off-by: Kuppuswamy Sathyanarayanan >> --- >> drivers/pci/ats.c | 10 ++++++---- >> include/linux/pci-ats.h | 12 +++++++++--- >> 2 files changed, 15 insertions(+), 7 deletions(-) >> >> diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c >> index e18499243f84..cdd936d10f68 100644 >> --- a/drivers/pci/ats.c >> +++ b/drivers/pci/ats.c >> @@ -395,6 +395,8 @@ int pci_pasid_features(struct pci_dev *pdev) >> } >> EXPORT_SYMBOL_GPL(pci_pasid_features); >> >> +#ifdef CONFIG_PCI_PRI >> + >> /** >> * pci_prg_resp_pasid_required - Return PRG Response PASID Required bit >> * status. >> @@ -402,10 +404,8 @@ EXPORT_SYMBOL_GPL(pci_pasid_features); >> * >> * Returns 1 if PASID is required in PRG Response Message, 0 otherwise. >> * >> - * Even though the PRG response PASID status is read from PRI Status >> - * Register, since this API will mainly be used by PASID users, this >> - * function is defined within #ifdef CONFIG_PCI_PASID instead of >> - * CONFIG_PCI_PRI. >> + * Since this API has dependency on both PRI and PASID, protect it >> + * with both CONFIG_PCI_PRI and CONFIG_PCI_PASID. >> */ >> int pci_prg_resp_pasid_required(struct pci_dev *pdev) >> { >> @@ -425,6 +425,8 @@ int pci_prg_resp_pasid_required(struct pci_dev *pdev) >> } >> EXPORT_SYMBOL_GPL(pci_prg_resp_pasid_required); >> >> +#endif >> + >> #define PASID_NUMBER_SHIFT 8 >> #define PASID_NUMBER_MASK (0x1f << PASID_NUMBER_SHIFT) >> /** >> diff --git a/include/linux/pci-ats.h b/include/linux/pci-ats.h >> index 1ebb88e7c184..1a0bdaee2f32 100644 >> --- a/include/linux/pci-ats.h >> +++ b/include/linux/pci-ats.h >> @@ -40,7 +40,6 @@ void pci_disable_pasid(struct pci_dev *pdev); >> void pci_restore_pasid_state(struct pci_dev *pdev); >> int pci_pasid_features(struct pci_dev *pdev); >> int pci_max_pasids(struct pci_dev *pdev); >> -int pci_prg_resp_pasid_required(struct pci_dev *pdev); >> >> #else /* CONFIG_PCI_PASID */ >> >> @@ -67,11 +66,18 @@ static inline int pci_max_pasids(struct pci_dev *pdev) >> return -EINVAL; >> } >> >> +#endif /* CONFIG_PCI_PASID */ >> + >> +#if defined(CONFIG_PCI_PRI) && defined(CONFIG_PCI_PASID) >> + >> +int pci_prg_resp_pasid_required(struct pci_dev *pdev); >> + >> +#else /* CONFIG_PCI_PASID && CONFIG_PCI_PRI */ >> + >> static inline int pci_prg_resp_pasid_required(struct pci_dev *pdev) >> { >> return 0; >> } >> -#endif /* CONFIG_PCI_PASID */ >> - >> +#endif >> >> #endif /* LINUX_PCI_ATS_H*/ >> -- >> 2.21.0 >> -- Sathyanarayanan Kuppuswamy Linux kernel developer