DPDK patches and discussions
 help / color / mirror / Atom feed
From: "Burakov, Anatoly" <anatoly.burakov@intel.com>
To: Xiao Wang <xiao.w.wang@intel.com>, dev@dpdk.org
Cc: zhihong.wang@intel.com, maxime.coquelin@redhat.com,
	yliu@fridaylinux.org,  cunming.liang@intel.com,
	rosen.xu@intel.com, junjie.j.chen@intel.com, dan.daly@intel.com
Subject: Re: [dpdk-dev] [PATCH 1/3] eal/vfio: add support for multiple container
Date: Wed, 14 Mar 2018 12:08:25 +0000	[thread overview]
Message-ID: <009ea590-d174-c153-7190-83b240b2053a@intel.com> (raw)
In-Reply-To: <20180309230809.63361-2-xiao.w.wang@intel.com>

On 09-Mar-18 11:08 PM, Xiao Wang wrote:
> From: Junjie Chen <junjie.j.chen@intel.com>
> 
> Currently eal vfio framework binds vfio group fd to the default
> container fd, while in some cases, e.g. vDPA (vhost data path
> acceleration), we want to set vfio group to a new container and
> program DMA mapping via this new container, so this patch adds
> APIs to support multiple container.
> 
> Signed-off-by: Junjie Chen <junjie.j.chen@intel.com>
> Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
> ---

I'm not going to get into virtual vs. real device debate, but i do have 
some issues with VFIO side of things.

I'm not completely convinced this change is needed in the first place. 
If the device driver manages its own groups anyway, it knows which VFIO 
groups belong to it, so it can add/remove them without putting them into 
separate containers. What is the purpose of keeping them in a separate 
container as opposed to just keeping track of group id's?

<...>


> +	vfio_cfg->vfio_container_fd = vfio_get_container_fd();
> +
> +	if (vfio_cfg->vfio_container_fd < 0)
> +		return -1;
> +
> +	return vfio_cfg->vfio_container_fd;
> +}

Please correct me if i'm wrong, but this patch appears to be mistitled. 
You're not really creating multiple containers, you're just partitioning 
existing one. Do we really need to open/store/close container fd's 
separately, if all we have is a single container anyway?

The semantics of this are also weird in multiprocess. When secondary 
process requests a container, we always create a new one, send it over 
IPC and close it afterwards. It seems to be oblivious that you may have 
several container fd's, and does not know which one you are asking for. 
We know it's all the same container, but that's clearly not what the 
code appears to be doing.

-- 
Thanks,
Anatoly

  reply	other threads:[~2018-03-14 12:08 UTC|newest]

Thread overview: 98+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-09 23:08 [dpdk-dev] [PATCH 0/3] add ifcvf driver Xiao Wang
2018-03-09 23:08 ` [dpdk-dev] [PATCH 1/3] eal/vfio: add support for multiple container Xiao Wang
2018-03-14 12:08   ` Burakov, Anatoly [this message]
2018-03-15 16:49     ` Wang, Xiao W
2018-03-09 23:08 ` [dpdk-dev] [PATCH 2/3] bus/pci: expose sysfs parsing API Xiao Wang
2018-03-14 11:19   ` Burakov, Anatoly
2018-03-14 13:30     ` Gaëtan Rivet
2018-03-15 16:49       ` Wang, Xiao W
2018-03-15 17:19         ` Gaëtan Rivet
2018-03-19  1:31           ` Wang, Xiao W
2018-03-21 13:21   ` [dpdk-dev] [PATCH v2 0/3] add ifcvf driver Xiao Wang
2018-03-21 13:21     ` [dpdk-dev] [PATCH v2 1/3] eal/vfio: add support for multiple container Xiao Wang
2018-03-21 20:32       ` Thomas Monjalon
2018-03-21 21:37         ` Gaëtan Rivet
2018-03-22  3:00           ` Wang, Xiao W
2018-03-21 13:21     ` [dpdk-dev] [PATCH v2 2/3] bus/pci: expose sysfs parsing API Xiao Wang
2018-03-21 20:44       ` Thomas Monjalon
2018-03-22  2:46         ` Wang, Xiao W
2018-03-21 13:21     ` [dpdk-dev] [PATCH v2 3/3] net/ifcvf: add ifcvf driver Xiao Wang
2018-03-21 20:52       ` Thomas Monjalon
2018-03-23 10:39         ` Wang, Xiao W
2018-03-21 20:57       ` Maxime Coquelin
2018-03-23 10:37         ` Wang, Xiao W
2018-03-22  8:51       ` Ferruh Yigit
2018-03-22 17:23         ` Wang, Xiao W
2018-03-31  2:29       ` [dpdk-dev] [PATCH v3 0/3] add ifcvf vdpa driver Xiao Wang
2018-03-31  2:29         ` [dpdk-dev] [PATCH v3 1/4] eal/vfio: add support for multiple container Xiao Wang
2018-03-31 11:06           ` Maxime Coquelin
2018-03-31  2:29         ` [dpdk-dev] [PATCH v3 2/4] net/virtio: skip device probe in vdpa mode Xiao Wang
2018-03-31 11:13           ` Maxime Coquelin
2018-03-31 13:16             ` Thomas Monjalon
2018-04-02  4:08               ` Wang, Xiao W
2018-03-31  2:29         ` [dpdk-dev] [PATCH v3 3/4] net/ifcvf: add ifcvf vdpa driver Xiao Wang
2018-03-31 11:26           ` Maxime Coquelin
2018-04-03  9:38             ` Wang, Xiao W
2018-04-04 14:40           ` [dpdk-dev] [PATCH v4 0/4] " Xiao Wang
2018-04-04 14:40             ` [dpdk-dev] [PATCH v4 1/4] eal/vfio: add multiple container support Xiao Wang
2018-04-05 18:06               ` [dpdk-dev] [PATCH v5 0/4] add ifcvf vdpa driver Xiao Wang
2018-04-05 18:06                 ` [dpdk-dev] [PATCH v5 1/4] eal/vfio: add multiple container support Xiao Wang
2018-04-05 18:06                 ` [dpdk-dev] [PATCH v5 2/4] net/virtio: skip device probe in vdpa mode Xiao Wang
2018-04-11 18:58                   ` Ferruh Yigit
2018-04-05 18:07                 ` [dpdk-dev] [PATCH v5 3/4] net/ifcvf: add ifcvf vdpa driver Xiao Wang
2018-04-11 18:58                   ` Ferruh Yigit
2018-04-12  7:19                   ` [dpdk-dev] [PATCH v6 0/4] " Xiao Wang
2018-04-12  7:19                     ` [dpdk-dev] [PATCH v6 1/4] eal/vfio: add multiple container support Xiao Wang
2018-04-12 14:03                       ` Burakov, Anatoly
2018-04-12 16:07                         ` Wang, Xiao W
2018-04-12 16:24                           ` Burakov, Anatoly
2018-04-13  9:18                             ` Wang, Xiao W
2018-04-15 15:33                       ` [dpdk-dev] [PATCH v7 0/5] add ifcvf vdpa driver Xiao Wang
2018-04-15 15:33                         ` [dpdk-dev] [PATCH v7 1/5] vfio: extend data structure for multi container Xiao Wang
2018-04-16 10:02                           ` Burakov, Anatoly
2018-04-16 12:22                             ` Wang, Xiao W
2018-04-16 15:34                           ` [dpdk-dev] [PATCH v8 0/5] add ifcvf vdpa driver Xiao Wang
2018-04-16 15:34                             ` [dpdk-dev] [PATCH v8 1/5] vfio: extend data structure for multi container Xiao Wang
2018-04-16 15:56                               ` Burakov, Anatoly
2018-04-16 15:34                             ` [dpdk-dev] [PATCH v8 2/5] vfio: add multi container support Xiao Wang
2018-04-16 15:58                               ` Burakov, Anatoly
2018-04-17  7:06                               ` [dpdk-dev] [PATCH v9 0/5] add ifcvf vdpa driver Xiao Wang
2018-04-17  7:06                                 ` [dpdk-dev] [PATCH v9 1/5] vfio: extend data structure for multi container Xiao Wang
2018-04-17  7:06                                 ` [dpdk-dev] [PATCH v9 2/5] vfio: add multi container support Xiao Wang
2018-04-17  7:06                                 ` [dpdk-dev] [PATCH v9 3/5] net/virtio: skip device probe in vdpa mode Xiao Wang
2018-04-17  7:06                                 ` [dpdk-dev] [PATCH v9 4/5] net/ifcvf: add ifcvf vdpa driver Xiao Wang
2018-04-17  7:06                                 ` [dpdk-dev] [PATCH v9 5/5] doc: add ifcvf driver document and release note Xiao Wang
2018-04-17 11:13                                 ` [dpdk-dev] [PATCH v9 0/5] add ifcvf vdpa driver Ferruh Yigit
2018-04-16 15:34                             ` [dpdk-dev] [PATCH v8 3/5] net/virtio: skip device probe in vdpa mode Xiao Wang
2018-04-16 15:34                             ` [dpdk-dev] [PATCH v8 4/5] net/ifcvf: add ifcvf vdpa driver Xiao Wang
2018-04-16 15:34                             ` [dpdk-dev] [PATCH v8 5/5] doc: add ifcvf driver document and release note Xiao Wang
2018-04-16 16:36                             ` [dpdk-dev] [PATCH v8 0/5] add ifcvf vdpa driver Ferruh Yigit
2018-04-16 18:07                               ` Thomas Monjalon
2018-04-17  5:36                                 ` Wang, Xiao W
2018-04-15 15:33                         ` [dpdk-dev] [PATCH v7 2/5] vfio: add multi container support Xiao Wang
2018-04-16 10:03                           ` Burakov, Anatoly
2018-04-16 12:44                             ` Wang, Xiao W
2018-04-15 15:33                         ` [dpdk-dev] [PATCH v7 3/5] net/virtio: skip device probe in vdpa mode Xiao Wang
2018-04-15 15:33                         ` [dpdk-dev] [PATCH v7 4/5] net/ifcvf: add ifcvf vdpa driver Xiao Wang
2018-04-15 15:33                         ` [dpdk-dev] [PATCH v7 5/5] doc: add ifcvf driver document and release note Xiao Wang
2018-04-12  7:19                     ` [dpdk-dev] [PATCH v6 2/4] net/virtio: skip device probe in vdpa mode Xiao Wang
2018-04-12  7:19                     ` [dpdk-dev] [PATCH v6 3/4] net/ifcvf: add ifcvf vdpa driver Xiao Wang
2018-04-12  7:19                     ` [dpdk-dev] [PATCH v6 4/4] doc: add ifcvf driver document and release note Xiao Wang
2018-04-05 18:07                 ` [dpdk-dev] [PATCH v5 " Xiao Wang
2018-04-11 18:59                 ` [dpdk-dev] [PATCH v5 0/4] add ifcvf vdpa driver Ferruh Yigit
2018-04-12  5:47                   ` Wang, Xiao W
2018-04-04 14:40             ` [dpdk-dev] [PATCH v4 2/4] net/virtio: skip device probe in vdpa mode Xiao Wang
2018-04-04 14:40             ` [dpdk-dev] [PATCH v4 3/4] net/ifcvf: add ifcvf vdpa driver Xiao Wang
2018-04-04 14:40             ` [dpdk-dev] [PATCH v4 4/4] doc: add ifcvf driver document and release note Xiao Wang
2018-03-31  2:29         ` [dpdk-dev] [PATCH v3 4/4] net/ifcvf: add " Xiao Wang
2018-03-31 11:28           ` Maxime Coquelin
2018-03-09 23:08 ` [dpdk-dev] [PATCH 3/3] net/ifcvf: add ifcvf driver Xiao Wang
2018-03-10 18:23 ` [dpdk-dev] [PATCH 0/3] " Maxime Coquelin
2018-03-15 16:49   ` Wang, Xiao W
2018-03-21 20:47     ` Maxime Coquelin
2018-03-23 10:27       ` Wang, Xiao W
2018-03-25  9:51         ` Maxime Coquelin
2018-03-26  9:05           ` Wang, Xiao W
2018-03-26 13:29             ` Maxime Coquelin
2018-03-27  4:40               ` Wang, Xiao W
2018-03-27  5:09                 ` Maxime Coquelin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=009ea590-d174-c153-7190-83b240b2053a@intel.com \
    --to=anatoly.burakov@intel.com \
    --cc=cunming.liang@intel.com \
    --cc=dan.daly@intel.com \
    --cc=dev@dpdk.org \
    --cc=junjie.j.chen@intel.com \
    --cc=maxime.coquelin@redhat.com \
    --cc=rosen.xu@intel.com \
    --cc=xiao.w.wang@intel.com \
    --cc=yliu@fridaylinux.org \
    --cc=zhihong.wang@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).