Path: csiph.com!eternal-september.org!feeder.eternal-september.org!aioe.org!bofh.it!news.nic.it!robomod From: Stephen Hemminger Newsgroups: linux.kernel Subject: Re: [dpdk-dev] [PATCH 0/2] uio_msi: device driver Date: Fri, 02 Oct 2015 00:10:02 +0200 Message-ID: References: X-Original-To: Alexander Duyck X-Google-Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-type:content-transfer-encoding; bh=eLxLEcvM6NJcVe0WVnbCO4ozGeovSZ3Vy1mFcTrpW7Q=; b=F0TsS2gz0hVn0ML0iBV60vyCYGVGtO/ucjSAFoEm1cZSJHVLVq3QZdFtKLjm7TYZN7 SNU1/OTus7YxBjO0F/qvRKEEymuX7K3mAAOf/aOVj2vlbTwWMlVB4BLjtz7cmFLV8rgh V3R9ucw36bSBWODPizZND5n6bYEy0GUPW5scff5DU0A9Ya38OPef+JpyDnEBefGe5y7H 9SBb6sozfKi8RcJUvlBs2l1p2WPnA7+ulecTd0Y6Wn1jDioePRoaDTOqxnY1OSxbdJhs DWNhRsS7HC9PAGx+BreIWzcgB7GFcSF65ZWb1Yb6gm+1qMXVSWm9YldQuLxmmBV2NTT2 uc1g== X-Gm-Message-State: ALoCoQmek9t1ctrJOHLis5q8wNpiYUHgFjw0H35NMqM5OCvCJ+Z2+pSfp9t37HqMzNcDJEXoH/jZ X-Received: by 10.66.219.8 with SMTP id pk8mr4839806pac.138.1443736827043; Thu, 01 Oct 2015 15:00:27 -0700 (PDT) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 36 Organization: linux.* mail to news gateway X-Original-Cc: Avi Kivity , dev@dpdk.org, hjk@hansjkoch.de, gregkh@linux-foundation.org, linux-kernel@vger.kernel.org X-Original-Date: Thu, 1 Oct 2015 15:00:36 -0700 X-Original-Message-ID: <20151001150036.7a20b228@urahara> X-Original-References: <1443652138-31782-1-git-send-email-stephen@networkplumber.org> <560D11F6.2080609@scylladb.com> <20151001075731.2f079237@urahara> <560D8E14.5030500@gmail.com> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1237774 On Thu, 1 Oct 2015 12:48:36 -0700 Alexander Duyck wrote: > On 10/01/2015 07:57 AM, Stephen Hemminger wrote: > > On Thu, 1 Oct 2015 13:59:02 +0300 > > Avi Kivity wrote: > > > >> On 10/01/2015 01:28 AM, Stephen Hemminger wrote: > >>> This is a new UIO device driver to allow supporting MSI-X and MSI devices > >>> in userspace. It has been used in environments like VMware and older versions > >>> of QEMU/KVM where no IOMMU support is available. > >> Why not add msi/msix support to uio_pci_generic? > > That is possible but that would meet ABI and other resistance from the author. > > Also, uio_pci_generic makes it harder to find resources since it doesn't fully > > utilize UIO infrastructure. > > I'd say you are better off actually taking this in the other direction. > From what I have seen it seems like this driver is meant to deal with > mapping VFs contained inside of guests. If you are going to fork off > and create a UIO driver for mapping VFs why not just make it specialize > in that. You could probably simplify the code by dropping support for > legacy interrupts and IO regions since all that is already covered by > uio_pci_generic anyway if I am not mistaken. > > You could then look at naming it something like uio_vf since the uio_msi > is a bit of a misnomer since it is MSI-X it supports, not MSI interrupts. The support needs to cover: - VF in guest - VNIC in guest (vmxnet3) it isn't just about VF's -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/