diff mbox

[dpdk-dev,v6,9/9] doc: dynamic rss configuration for bonding

Message ID 1444989651-6236-10-git-send-email-tomaszx.kulasek@intel.com (mailing list archive)
State Superseded, archived
Headers

Commit Message

Tomasz Kulasek Oct. 16, 2015, 10 a.m. UTC 
  Documentation update about implementation details and requirements for
Dynamic RSS Configuration for Bonding.

Signed-off-by: Tomasz Kulasek <tomaszx.kulasek@intel.com>
---
 .../prog_guide/link_bonding_poll_mode_drv_lib.rst  |   34 ++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/doc/guides/prog_guide/link_bonding_poll_mode_drv_lib.rst b/doc/guides/prog_guide/link_bonding_poll_mode_drv_lib.rst
index 03baf90..46f0296 100644
--- a/doc/guides/prog_guide/link_bonding_poll_mode_drv_lib.rst
+++ b/doc/guides/prog_guide/link_bonding_poll_mode_drv_lib.rst
@@ -1,5 +1,5 @@ 
 ..  BSD LICENSE
-    Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+    Copyright(c) 2010-2015 Intel Corporation. All rights reserved.
     All rights reserved.
 
     Redistribution and use in source and binary forms, with or without
@@ -173,7 +173,28 @@  After a slave device is added to a bonded device slave is stopped using
 ``rte_eth_dev_stop`` and then reconfigured using ``rte_eth_dev_configure``
 the RX and TX queues are also reconfigured using ``rte_eth_tx_queue_setup`` /
 ``rte_eth_rx_queue_setup`` with the parameters use to configure the bonding
-device.
+device. If RSS is enabled for bonding device, this mode is also enabled on new
+slave and configured as well.
+
+Setting up multi-queue mode for bonding device to RSS, makes it fully
+RSS-capable, so all slaves are synchronized with its configuration. This mode is
+intended to provide RSS configuration on slaves transparent for client
+application implementation.
+
+Bonding device stores its own version of RSS settings i.e. RETA, RSS hash
+function and RSS key, used to set up its slaves. That let to define the meaning
+of RSS configuration of bonding device as desired configuration of whole bonding
+(as one unit), without pointing any of slave inside. It is required to ensure
+consistency and made it more errorproof.
+
+RSS hash function set for bonding device, is a maximal set of RSS hash functions
+supported by all bonded slaves. RETA size is a GCD of all its RETA's sizes, so
+it can be easily used as a pattern providing expected behavior, even if slave
+RETAs' sizes are different. If RSS Key is not set for bonded device, it's not
+changed on the slaves and default key for device is used.
+
+All settings are managed through the bonding port API and always are propagated
+in one direction (from bonding to slaves).
 
 Link Status Change Interrupts / Polling
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -207,6 +228,15 @@  these parameters.
 A bonding device must have a minimum of one slave before the bonding device
 itself can be started.
 
+To use a bonding device dynamic RSS configuration feature effectively, it is
+also required, that all slaves should be RSS-capable and support, at least one
+common hash function available for each of them. Changing RSS key is only
+possible, when all slave devices support the same key size.
+
+To prevent inconsistency on how slaves process packets, once a device is added
+to a bonding device, RSS configuration should be managed through the bonding
+device API, and not directly on the slave.
+
 Like all other PMD, all functions exported by a PMD are lock-free functions
 that are assumed not to be invoked in parallel on different logical cores to
 work on the same target object.