From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?iso-8859-1?Q?Ga=EBtan?= Rivet Subject: Re: [PATCH v10 05/11] net/failsafe: add flexible device definition Date: Mon, 17 Jul 2017 17:52:26 +0200 Message-ID: <20170717155226.GQ11154@bidouze.vm.6wind.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Cc: dev@dpdk.org To: Ferruh Yigit Return-path: Received: from mail-wm0-f52.google.com (mail-wm0-f52.google.com [74.125.82.52]) by dpdk.org (Postfix) with ESMTP id 87C69376C for ; Mon, 17 Jul 2017 17:52:36 +0200 (CEST) Received: by mail-wm0-f52.google.com with SMTP id b134so52639680wma.0 for ; Mon, 17 Jul 2017 08:52:36 -0700 (PDT) Content-Disposition: inline In-Reply-To: List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Hi Ferruh, (Thanks for the review by the way, I will answer the other more lengthy emails in due time) On Mon, Jul 17, 2017 at 04:45:59PM +0100, Ferruh Yigit wrote: > On 7/15/2017 6:57 PM, Gaetan Rivet wrote: > > Add the "exec" device type. > > The parameters given to this type of device will be executed in a shell. > > The output of this command is then used as a definition for a device. > > > > That command can be re-interpreted if the related device is not > > plugged-in. It allows for a device definition to react to system > > changes (e.g. changing PCI bus for a given device). > > > > Signed-off-by: Gaetan Rivet > > Acked-by: Olga Shern > > --- > > doc/guides/nics/fail_safe.rst | 20 +++++++ > > drivers/net/failsafe/failsafe_args.c | 95 +++++++++++++++++++++++++++++++++ > > drivers/net/failsafe/failsafe_ether.c | 7 +++ > > drivers/net/failsafe/failsafe_private.h | 4 ++ > > 4 files changed, 126 insertions(+) > > > > diff --git a/doc/guides/nics/fail_safe.rst b/doc/guides/nics/fail_safe.rst > > index 5ec3031..be73d7e 100644 > > --- a/doc/guides/nics/fail_safe.rst > > +++ b/doc/guides/nics/fail_safe.rst > > @@ -87,6 +87,19 @@ Fail-safe command line parameters > > additional sub-device parameters if need be. They will be passed on to the > > sub-device. > > > > +- **exec()** parameter > > + > > + This parameter allows the user to provide a command to the fail-safe PMD to > > + execute and define a sub-device. > > + It is done within a regular shell context. > > + The first line of its output is read by the fail-safe PMD and otherwise > > + interpreted as if passed by the regular **dev** parameter. > > + Any other line is discarded. > > + If the command fail or output an incorrect string, the sub-device is not > > + initialized. > > + All commas within the ``shell command`` are replaced by spaces before > > + executing the command. This helps using scripts to specify devices. > > + > > - **mac** parameter [MAC address] > > > > This parameter allows the user to set a default MAC address to the fail-safe > > @@ -135,6 +148,13 @@ This section shows some example of using **testpmd** with a fail-safe PMD. > > -w 'net_failsafe0,mac=de:ad:be:ef:01:02,dev(84:00.0),dev(net_ring0)' > > -w 81:00.0 -- -i > > > > +#. Start testpmd using a flexible device definition > > + > > + .. code-block:: console > > + > > + $RTE_TARGET/build/app/testpmd -c 0xff -n 4 --no-pci \ > > + --vdev='net_failsafe0,exec(echo 84:00.0)' -- -i > > Hi Gaetan, > > What is the usecase for this feature. > > How this is different from --vdev='net_failsafe0,dev(`echo 84:00.0`)' ? This version would be interpreted once, at the launch of the fail-safe PMD. The exec option will execute the command again each time the fail-safe tries to probe the sub_device. This means that in a live VM migration context, the sub_device can change PCI address (for example), and still be matched by the command using other identifying info (MAC address, class_id, ...). It must be reinterpreted upon plugin of the sub_device, as the output would change from the time the fail-safe was started. -- Gaëtan Rivet 6WIND