On Tue, Mar 07, 2023 at 04:23:26PM -0500, Xin Long wrote: > As it says in rfc8260#section-3.5 about the fair capacity scheduler: > > A fair capacity distribution between the streams is used. This > scheduler considers the lengths of the messages of each stream and > schedules them in a specific way to maintain an equal capacity for > all streams. The details are implementation dependent. interleaving > user messages allows for a better realization of the fair capacity > usage. > > This patch adds Fair Capacity Scheduler based on the foundations added > by commit 5bbbbe32a431 ("sctp: introduce stream scheduler foundations"): > > A fc_list and a fc_length are added into struct sctp_stream_out_ext and > a fc_list is added into struct sctp_stream. In .enqueue, when there are > chunks enqueued into a stream, this stream will be linked into stream-> > fc_list by its fc_list ordered by its fc_length. In .dequeue, it always > picks up the 1st skb from stream->fc_list. In .dequeue_done, fc_length > is increased by chunk's len and update its location in stream->fc_list > according to the its new fc_length. > > Note that when the new fc_length overflows in .dequeue_done, instead of > resetting all fc_lengths to 0, we only reduced them by U32_MAX / 4 to > avoid a moment of imbalance in the scheduling, as Marcelo suggested. > > Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx>