From patchwork Tue Dec 19 17:58:13 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Wang X-Patchwork-Id: 32402 X-Patchwork-Delegate: thomas@monjalon.net Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id BC61D1B00B; Tue, 19 Dec 2017 10:21:32 +0100 (CET) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by dpdk.org (Postfix) with ESMTP id 86EB1324B for ; Tue, 19 Dec 2017 10:21:31 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Dec 2017 01:21:30 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.45,425,1508828400"; d="scan'208";a="4035088" Received: from dpdk-xiao-1.sh.intel.com ([10.67.110.153]) by orsmga006.jf.intel.com with ESMTP; 19 Dec 2017 01:21:28 -0800 From: Xiao Wang To: ferruh.yigit@intel.com Cc: dev@dpdk.org, stephen@networkplumber.org, tiwei.bie@intel.com, Xiao Wang Date: Tue, 19 Dec 2017 09:58:13 -0800 Message-Id: <1513706293-133528-1-git-send-email-xiao.w.wang@intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1513698140-92837-1-git-send-email-xiao.w.wang@intel.com> References: <1513698140-92837-1-git-send-email-xiao.w.wang@intel.com> Subject: [dpdk-dev] [PATCH v3] igb_uio: allow multi-process access X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" In some case, one device are accessed by different processes via different BARs, so one uio device may be opened by more than one process, for this case we just need to enable interrupt once, and pci_clear_master only when the last process closed. Fixes: 5f6ff30dc507 ("igb_uio: fix interrupt enablement after FLR in VM") Signed-off-by: Xiao Wang --- v3: - Use atomic_inc_return instead of atomic_inc and atomic_read. - Ditto for atomic_dec. v2: - Make uio reference counter operation atomic. --- lib/librte_eal/linuxapp/igb_uio/igb_uio.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c index a3a98c1..8f40c01 100644 --- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c +++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c @@ -45,6 +45,7 @@ struct rte_uio_pci_dev { struct uio_info info; struct pci_dev *pdev; enum rte_intr_mode mode; + atomic_t refcnt; }; static char *intr_mode; @@ -336,6 +337,9 @@ struct rte_uio_pci_dev { struct pci_dev *dev = udev->pdev; int err; + if (atomic_inc_return(&udev->refcnt) > 1) + return 0; + /* set bus master, which was cleared by the reset function */ pci_set_master(dev); @@ -354,6 +358,9 @@ struct rte_uio_pci_dev { struct rte_uio_pci_dev *udev = info->priv; struct pci_dev *dev = udev->pdev; + if (atomic_dec_return(&udev->refcnt) > 0) + return 0; + /* disable interrupts */ igbuio_pci_disable_interrupts(udev);