From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:49983 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755143Ab2JBVGm (ORCPT ); Tue, 2 Oct 2012 17:06:42 -0400 Message-ID: <506B575A.4060304@redhat.com> Date: Tue, 02 Oct 2012 17:06:34 -0400 From: Don Dutile MIME-Version: 1.0 To: Greg Kroah-Hartman CC: Yinghai Lu , linux-pci@vger.kernel.org, bhelgaas@google.com, yuvalmin@broadcom.com, bhutchings@solarflare.com, gregory.v.rose@intel.com, davem@davemloft.net Subject: Re: [RFC] PCI: enable and disable sriov support via sysfs at per device level References: <1349134020-62152-1-git-send-email-ddutile@redhat.com> <506B4D4C.3080101@redhat.com> <20121002203951.GA28663@kroah.com> In-Reply-To: <20121002203951.GA28663@kroah.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: On 10/02/2012 04:39 PM, Greg Kroah-Hartman wrote: > On Tue, Oct 02, 2012 at 04:23:40PM -0400, Don Dutile wrote: >> Greg: Why not use the above functions? > > What "above functions"? You make a lot of calls in the code :) > > You are creating an attribute group, and then manually walking through > it to create/destroy the file? That's not good, use the in-kernel > functions to do that automatically for you. > > Also, you need to do this _before_ the device shows up to userspace, > otherwise you have a race that you just lost with udev and the like. > > thanks, > > greg k-h So, why is it ok to create the 'reset' file after the device shows up? Like reset, SRIOV is optional. The sysfs files are designed to only be used by userspace utils to enable/disable VFs after the system is up. Or should the design allow a udev rule to be created that if one of these new sriov files exists, then perform a set of read-max-vf & enable n-vf ops ?