From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id AFB4E5AA8 for ; Mon, 27 Jun 2016 07:09:01 +0200 (CEST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP; 26 Jun 2016 22:08:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,535,1459839600"; d="scan'208";a="725470581" Received: from unknown (HELO yliu-dev) ([10.239.67.162]) by FMSMGA003.fm.intel.com with ESMTP; 26 Jun 2016 22:08:52 -0700 Date: Mon, 27 Jun 2016 13:08:52 +0800 From: Yuanhan Liu To: "Mcnamara, John" Cc: "dev@dpdk.org" , "Xie, Huawei" , Thomas Monjalon Message-ID: <20160627050852.GU23111@yliu-dev.sh.intel.com> References: <1466754768-4809-1-git-send-email-yuanhan.liu@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Subject: Re: [dpdk-dev] [PATCH] doc: update vhost guide X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 27 Jun 2016 05:09:02 -0000 On Sun, Jun 26, 2016 at 08:28:12PM +0000, Mcnamara, John wrote: > > -----Original Message----- > > From: Yuanhan Liu [mailto:yuanhan.liu@linux.intel.com] > > Sent: Friday, June 24, 2016 8:53 AM > > To: dev@dpdk.org > > Cc: Xie, Huawei ; Mcnamara, John > > ; Thomas Monjalon ; > > Yuanhan Liu > > Subject: [PATCH] doc: update vhost guide > > > > Mainly on updating vhost-user part: we now support client mode. > > Also refine some words, and add a bit more explanation. > > > > And made an emphatic statement that you are suggested to use vhost-user > > instead of vhost-cuse, because we have enhanced vhost-user a lot since > > v2.2 (Actually, I doubt there are any people still using vhost-cuse) > > Hi Yuahan, > > Nice doc and updates. Some minor comments below. > > > > + > > +* access the guest memory > > + > > + For QEMU, this is done by using **-object > > + memory-backend-file,share=on,...** > > + option. Which means QEMU will create a file to serve as the guest RAM. > > + The **share=on** option allows another process to map that file, > > + which means it can access the guest RAM. > > Fixed width quotes `` `` would be better here than bold ** **. > > > > +Currently, there are two ways to pass those messages. That results to > > +we have two implementations: vhost-cuse (character devices in user > > +space) and vhost-user. Vhost-cuse creates a user space char dev and > > +hook a function ioctl, so that all ioctl commands (that represent those > > +messages) sent from the frontend (QEMU) will be captured and handled. > > +While vhost-user creates a Unix domain socket file, through which those > > messages are passed. > > Probably better to separate the vhost-cuse and vhost-user into 2 paragraphs > to make the text clearer. > > Also, it is probably better to standardize on using a hyphen in vhost-cuse > and vhost-user throughout the doc; there are cases with and without. Yes, we should. > > > +Note that since DPDK v2.2, we have spent a lot of efforts on enhancing > > +vhost-user, such as multiple queue, live migration, reconnect, etc. > > +Thus, **you are encouraged to use vhost-user instead of vhost-cuse**. > > In general I prefer to use a simple "Note" in the text, like this, rather > that the RST Note:: directive which creates a more distinctive but usually > unnecessary callout box. However in this case it is probably worth having > this recommendation displayed prominently. Something like the following: > > .. Note:: > > Since DPDK v2.2, the majority of the development effort has gone into > enhancing vhost-user, such as multiple queue, live migration, and > reconnect. Thus, it is strongly advised to use vhost-user instead of > vhost-cuse. Much better! I also like the reword a lot. > > > * VHOST_SET_LOG_FD > > * VHOST_SET_VRING_ERR > > Probably best to prefix this list with a sentence that explains what they > are. Yes, indeed. But I was thinking to defer this task to some point that I could have plenty time to think about how to rewrite the vhost and vhost example doc properly. So far, it's just a short update. > Something like: > > The supported vhost messages are: > > * ``VHOST_SET_MEM_TABLE`` > * ``VHOST_SET_VRING_KICK`` > * ``VHOST_SET_VRING_CALL`` > * ``VHOST_SET_LOG_FD`` > * ``VHOST_SET_VRING_ERR`` > > Also, use fixed width quotes here and elsewhere for function or variable > names coming from code. > > I will send you on some other suggestions. Thanks a lot for the suggestions. --yliu