X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=doc%2Fguides%2Fnics%2Ffail_safe.rst;h=34ecae2d1933696caa72bd9ced8af17e89d7122c;hb=76f5f48c51ccbb5ab696af6ae22a7c1acbe63a07;hp=000589235ecb463e5368e24401948612caf449ff;hpb=ebea83f899d8739e7143209e7575aa97f4f3ab08;p=dpdk.git

diff --git a/doc/guides/nics/fail_safe.rst b/doc/guides/nics/fail_safe.rst
index 000589235e..34ecae2d19 100644
--- a/doc/guides/nics/fail_safe.rst
+++ b/doc/guides/nics/fail_safe.rst
@@ -51,6 +51,12 @@ The Fail-safe PMD only supports a limited set of features. If you plan to use a
 device underneath the Fail-safe PMD with a specific feature, this feature must
 be supported by the Fail-safe PMD to avoid throwing any error.
 
+A notable exception is the device removal feature. The fail-safe PMD being a
+virtual device, it cannot currently be removed in the sense of a specific bus
+hotplug, like for PCI for example. It will however enable this feature for its
+sub-device automatically, detecting those that are capable and register the
+relevant callback for such event.
+
 Check the feature matrix for the complete set of supported features.
 
 Compilation option
@@ -87,6 +93,19 @@ 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
@@ -134,6 +153,13 @@ This section shows some example of using **testpmd** with a fail-safe PMD.
          --vdev '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
+
 Using the Fail-safe PMD from an application
 -------------------------------------------
 
@@ -159,6 +185,14 @@ apply it upon the probing of its missing sub-device. After this configuration
 pass, the new sub-device will be synchronized with other sub-devices, i.e. be
 started if the fail-safe PMD has been started by the user before.
 
+Plug-out feature
+----------------
+
+A sub-device supporting the device removal event can be removed from its bus at
+any time. The fail-safe PMD will register a callback for such event and react
+accordingly. It will try to safely stop, close and uninit the sub-device having
+emitted this event, allowing it to free its eventual resources.
+
 Fail-safe glossary
 ------------------
 
@@ -175,6 +209,7 @@ Preferred device : Primary device
 Upkeep round
     Periodical process when slaves are serviced. Each devices having a state
     different to that of the fail-safe device itself, is synchronized with it.
+    Additionally, each slave having the remove flag set are cleaned-up.
 
 Slave
     In the context of the fail-safe PMD, synonymous to sub-device.