From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by dpdk.org (Postfix) with ESMTP id 685D537B0 for ; Thu, 4 Oct 2018 07:05:36 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Oct 2018 22:05:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,338,1534834800"; d="scan'208";a="76068406" Received: from jguo15x-mobl.ccr.corp.intel.com (HELO [10.249.174.2]) ([10.249.174.2]) by fmsmga008.fm.intel.com with ESMTP; 03 Oct 2018 22:05:30 -0700 To: "Burakov, Anatoly" , stephen@networkplumber.org, bruce.richardson@intel.com, ferruh.yigit@intel.com, konstantin.ananyev@intel.com, gaetan.rivet@6wind.com, jingjing.wu@intel.com, thomas@monjalon.net, motih@mellanox.com, matan@mellanox.com, harry.van.haaren@intel.com, qi.z.zhang@intel.com, shaopeng.he@intel.com, bernard.iremonger@intel.com, arybchenko@solarflare.com Cc: jblunck@infradead.org, shreyansh.jain@nxp.com, dev@dpdk.org, helin.zhang@intel.com, jerin.jacob@caviumnetworks.com References: <1534503091-31910-1-git-send-email-jia.guo@intel.com> <1538485138-98076-1-git-send-email-jia.guo@intel.com> <1538485138-98076-5-git-send-email-jia.guo@intel.com> <628bc5ca-de09-0b54-8e1a-c0742ddb6890@intel.com> From: Jeff Guo Message-ID: <0cee54a9-99ec-c316-8d60-6169caf2c904@intel.com> Date: Thu, 4 Oct 2018 13:05:30 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.0 MIME-Version: 1.0 In-Reply-To: <628bc5ca-de09-0b54-8e1a-c0742ddb6890@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Subject: Re: [dpdk-dev] [PATCH v3 4/4] vfio: enable vfio hotplug by req notifier handler 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: , X-List-Received-Date: Thu, 04 Oct 2018 05:05:38 -0000 On 10/2/2018 10:15 PM, Burakov, Anatoly wrote: > On 02-Oct-18 1:58 PM, Jeff Guo wrote: >> When device is be hot-unplugged, the vfio kernel module will sent req >> notifier to request user space to release the allocated resources at >> first. After that, vfio kernel module will detect the device disappear, >> and then delete the device in kernel. >> >> This patch aim to add req notifier processing to enable hotplug for >> vfio. >> By enable the req notifier monitoring and register the notifier >> callback, >> when device be hot-unplugged, the hot-unplug handler will be called to >> process hotplug for vfio. >> >> Signed-off-by: Jeff Guo >> --- >> v3->v2: >> change some code style and typo. >> --- > > > >> +/* enable notifier (only enable req now) */ >> +static int >> +pci_vfio_enable_notifier(struct rte_pci_device *dev, int vfio_dev_fd) >> +{ >> +    int ret; >> +    int fd = -1; >> + >> +    /* set up an eventfd for req notifier */ >> +    fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC); >> +    if (fd < 0) { >> +        RTE_LOG(ERR, EAL, "Cannot set up eventfd, error %i (%s)\n", >> +            errno, strerror(errno)); >> +        return -1; >> +    } >> + >> +    dev->req_notifier_handler.fd = fd; >> +    dev->req_notifier_handler.type = RTE_INTR_HANDLE_VFIO_REQ; >> +    dev->req_notifier_handler.vfio_dev_fd = vfio_dev_fd; >> +    ret = rte_intr_callback_register(&dev->req_notifier_handler, >> +                     pci_vfio_req_handler, >> +                     (void *)&dev->device); >> +    if (ret) { >> +        RTE_LOG(ERR, EAL, "Fail to register req notifier handler.\n"); >> +        goto error; > > At this point (and further down as well), if we go to error, we've > already modified the req_notifier_handler data. Do we need to > overwrite it? Maybe just do these operations on a local struct, and > then do a memcpy into dev->req_notifier_handler on success? > I think just overwrite it in error process should be clear and simple.