Adds documentation for packet drop policy and Error Class of service Signed-off-by: Balasubramanian Manoharan <bala.manoha...@linaro.org> --- doc/users-guide/users-guide-cls.adoc | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-)
diff --git a/doc/users-guide/users-guide-cls.adoc b/doc/users-guide/users-guide-cls.adoc index d2ba743..b158122 100644 --- a/doc/users-guide/users-guide-cls.adoc +++ b/doc/users-guide/users-guide-cls.adoc @@ -109,7 +109,32 @@ pools. Multiple odp_pktio instances (i.e., multiple ports) may each have their own default odp_cos, or may share a odp_cos with other ports, based on application requirements. -Packet Classification +=== Error packet handling + +Any Error class of service is assigned to ingress port using the function +odp_pktio_error_cos_set(). All the packets received with error from this +specific ingress port are assigned to this error class-of-service. +At minimum this error class-of-service must have a queue and a buffer pool +assigned to it on platforms that support multiple packet buffer pools. +Multiple odp_pktio instances (_i.e.,_ multiple ports) may each have their own +error class of service, or may share an error CoS with other ports, based on +application requirements. + +=== Packet dropping + +Each class of service has a `drop_policy` configured during creation. The +valid value are ODP_COS_DROP_POOL and ODP_COS_DROP_NEVER. If the `drop_policy` +is set to ODP_COS_DROP_POOL then the packets assigned to the CoS follows the +drop policy of the associated pool _i.e.,_ depending on the Random Early Discard +or any other configuration of the pool the packet might get dropped. If the +`drop_policy` is set to ODP_COS_DROP_NEVER then the drop policy of the pool is +ignored and the packet is never dropped by the implementation. + +During creation of the Class of service if the pool or queue is set as INVALID +using ODP_POOL_INVALID or ODP_QUEUE_INVALID field then the packets received in +the specific CoS gets dropped by the implementation. + +=== Packet Classification For each odp_pktio port, the API allows the assignment of a class-of-service to a packet using one of three methods: @@ -136,7 +161,7 @@ destination or source port numbers, and appropriately assign these packets a class-of-service that maps to a higher priority queue, assuring voice packets a lower and bound latency. -Packet meta data Elements +=== Packet meta data Elements Here are the specific information elements that are stored within the packet meta data structure: -- 1.9.1 _______________________________________________ lng-odp mailing list lng-odp@lists.linaro.org https://lists.linaro.org/mailman/listinfo/lng-odp
