On 7/17/2017 4:52 PM, Gaëtan Rivet wrote: > 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 <gaetan.ri...@6wind.com> >>> Acked-by: Olga Shern <ol...@mellanox.com> >>> --- >>> 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(<shell command>)** 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.
Make sense, thanks for clarification.
