linux/net/sctp
Marcelo Ricardo Leitner 637784ade2 sctp: introduce priority based stream scheduler
This patch introduces RFC Draft ndata section 3.4 Priority Based
Scheduler (SCTP_SS_PRIO).

It works by having a struct sctp_stream_priority for each priority
configured. This struct is then enlisted on a queue ordered per priority
if, and only if, there is a stream with data queued, so that dequeueing
is very straightforward: either finish current datamsg or simply dequeue
from the highest priority queued, which is the next stream pointed, and
that's it.

If there are multiple streams assigned with the same priority and with
data queued, it will do round robin amongst them while respecting
datamsgs boundaries (when not using idata chunks), to be reasonably
fair.

We intentionally don't maintain a list of priorities nor a list of all
streams with the same priority to save memory. The first would mean at
least 2 other pointers per priority (which, for 1000 priorities, that
can mean 16kB) and the second would also mean 2 other pointers but per
stream. As SCTP supports up to 65535 streams on a given asoc, that's
1MB. This impacts when giving a priority to some stream, as we have to
find out if the new priority is already being used and if we can free
the old one, and also when tearing down.

The new fields in struct sctp_stream_out_ext and sctp_stream are added
under a union because that memory is to be shared with other schedulers.

See-also: https://tools.ietf.org/html/draft-ietf-tsvwg-sctp-ndata-13
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-03 16:27:29 -07:00
..
associola.c sctp: remove the typedef sctp_subtype_t 2017-08-06 21:33:42 -07:00
auth.c sctp: remove the typedef sctp_hmac_algo_param_t 2017-07-16 20:52:14 -07:00
bind_addr.c sctp: remove the typedef sctp_scope_t 2017-08-06 21:33:41 -07:00
chunk.c sctp: introduce struct sctp_stream_out_ext 2017-10-03 16:27:28 -07:00
debug.c sctp: remove the typedef sctp_subtype_t 2017-08-06 21:33:42 -07:00
endpointola.c sctp: remove the typedef sctp_subtype_t 2017-08-06 21:33:42 -07:00
input.c sctp: remove the typedef sctp_addip_chunk_t 2017-08-03 09:45:47 -07:00
inqueue.c sctp: remove the typedef sctp_chunkhdr_t 2017-07-01 09:08:41 -07:00
ipv6.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-08-21 17:06:42 -07:00
Kconfig sctp: add the sctp_diag.c file 2016-04-15 17:29:36 -04:00
Makefile sctp: introduce priority based stream scheduler 2017-10-03 16:27:29 -07:00
objcnt.c sctp: remove the typedef sctp_dbg_objcnt_entry_t 2017-08-11 10:02:43 -07:00
offload.c net: use skb->csum_not_inet to identify packets needing crc32c 2017-05-19 19:21:29 -04:00
output.c sctp: remove the typedef sctp_xmit_t 2017-08-06 21:33:42 -07:00
outqueue.c sctp: introduce stream scheduler foundations 2017-10-03 16:27:29 -07:00
primitive.c sctp: remove the typedef sctp_subtype_t 2017-08-06 21:33:42 -07:00
probe.c sctp: remove the typedef sctp_disposition_t 2017-08-11 10:02:44 -07:00
proc.c net: convert sock.sk_wmem_alloc from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
protocol.c sctp: remove the typedef sctp_scope_t 2017-08-06 21:33:41 -07:00
sctp_diag.c sctp: do not mark sk dumped when inet_sctp_diag_fill returns err 2017-09-15 14:51:15 -07:00
sm_make_chunk.c sctp: fix some indents in sm_make_chunk.c 2017-08-11 10:02:44 -07:00
sm_sideeffect.c sctp: introduce stream scheduler foundations 2017-10-03 16:27:29 -07:00
sm_statefuns.c sctp: remove the typedef sctp_disposition_t 2017-08-11 10:02:44 -07:00
sm_statetable.c sctp: remove the typedef sctp_sm_table_entry_t 2017-08-11 10:02:44 -07:00
socket.c sctp: add sockopt to get/set stream scheduler parameters 2017-10-03 16:27:29 -07:00
stream_sched_prio.c sctp: introduce priority based stream scheduler 2017-10-03 16:27:29 -07:00
stream_sched.c sctp: introduce priority based stream scheduler 2017-10-03 16:27:29 -07:00
stream.c sctp: introduce stream scheduler foundations 2017-10-03 16:27:29 -07:00
sysctl.c sctp: remove the typedef sctp_scope_policy_t 2017-08-06 21:33:41 -07:00
transport.c sctp: remove the typedef sctp_lower_cwnd_t 2017-08-06 21:33:41 -07:00
tsnmap.c sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
ulpevent.c sctp: remove the typedef sctp_errhdr_t 2017-08-03 09:45:46 -07:00
ulpqueue.c sctp: fix missing wake ups in some situations 2017-09-08 10:02:47 -07:00