[dpdk-dev] [PATCH v2 0/3] clarify eth_dev state management

[Gaetan Rivet <gaetan.rivet@6wind.com>]

1. The hotplug API currently available in DPDK introduces the notion of
   device states (DEV_DETACHED, DEV_ATTACHED). These states are implicit
   and internal to the ethdev layer.

2. Device enumeration and access is done directly, without regard to the
   underlying state of a device. Applications are currently expected to cycle
   through the static rte_eth_devices array. Those using the hotplug API
   (rte_eth_dev_attach(), rte_eth_dev_detach()), are thus expected to deal
   themselves with possible discrepancies internal to the ethdev layer,
   i.e. avoid detached devices if necessary, without the state of the devices
   having been explicitly defined or exposed.

3. The hotplug API itself is not complete and cannot be used without
   introducing some bugs. Detaching a device will introduce inconsistencies in
   the device count, as explained in the related API.
   No function is exposed in the ethdev layer to permit applications to deal
   with it.

This series addresses these issues so that:

1. Applications are not expected to manage the states of their devices, those
   should be kept internal to the ethdev layer.

2. The hotplug API is cleaner, with specific operations from the ethdev layer
   to be used if necessary.

3. Applications that are not interested in hotplug functionality are not concerned
   and do not require any change.

v1 --> v2:

 * Improved patches consistency, iterator definition in one patch only

 * Removed device count changes, not needed without additional device states.

Gaetan Rivet (3):
  ethdev: expose device states
  ethdev: add device iterator
  app/testpmd: use ethdev iterator to list devices

 app/test-pmd/cmdline.c        | 31 +++++++++++++++---------------
 app/test-pmd/cmdline_flow.c   |  2 +-
 app/test-pmd/config.c         | 12 ++++++------
 app/test-pmd/parameters.c     |  4 ++--
 app/test-pmd/testpmd.c        | 44 +++++++++++--------------------------------
 app/test-pmd/testpmd.h        |  9 ---------
 lib/librte_ether/rte_ethdev.c | 30 +++++++++++++++++------------
 lib/librte_ether/rte_ethdev.h | 31 ++++++++++++++++++++++++++++--
 8 files changed, 82 insertions(+), 81 deletions(-)

-- 
2.1.4