o Introduce a notion of "not ready" mbufs in socket buffers. These
mbufs are now being populated by some I/O in background and are
referenced outside. This forces following implications:
- An mbuf which is "not ready" can't be taken out of the buffer.
- An mbuf that is behind a "not ready" in the queue neither.
- If sockbet buffer is flushed, then "not ready" mbufs shouln't be
freed.
o In struct sockbuf the sb_cc field is split into sb_ccc and sb_acc.
The sb_ccc stands for ""claimed character count", or "committed
character count". And the sb_acc is "available character count".
Consumers of socket buffer API shouldn't already access them directly,
but use sbused() and sbavail() respectively.
o Not ready mbufs are marked with M_NOTREADY, and ready but blocked ones
with M_BLOCKED.
o New field sb_fnrdy points to the first not ready mbuf, to avoid linear
search.
o New function sbready() is provided to activate certain amount of mbufs
in a socket buffer.
A special note on SCTP:
SCTP has its own sockbufs. Unfortunately, FreeBSD stack doesn't yet
allow protocol specific sockbufs. Thus, SCTP does some hacks to make
itself compatible with FreeBSD: it manages sockbufs on its own, but keeps
sb_cc updated to inform the stack of amount of data in them. The new
notion of "not ready" data isn't supported by SCTP. Instead, only a
mechanical substitute is done: s/sb_cc/sb_ccc/.
A proper solution would be to take away struct sockbuf from struct
socket and allow protocols to implement their own socket buffers, like
SCTP already does. This was discussed with rrs@.
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
proprietary binary format.
* Add support for a diagnostic information error cause.
The code is sysctlable and the default is 0, which
means it is not sent.
This is joint work with rrs@.
MFC after: 1 week
ABORT cause, since the user can also provide this kind of
information. So the receiver doesn't know who provided the
information.
While there: Fix a bug where the stack would send a malformed
ABORT chunk when using a send() call with SCTP_ABORT|SCT_SENDALL
flags.
MFC after: 3 days
chunks for each SCTP outgoing stream are in the send and
sent queue.
While there, improve the naming of NR-SACK related constants
recently introduced.
MFC after: 1 week
actually in it. This happens when SCTP receives an unknown chunk, which
requires the sending of an ERROR chunk, and there is no final padding but
the chunk is not 4-byte aligned.
Reported by yueting via rwatson@
MFC after: 3 days
* Decouple the path supervision using a separate HB timer per path.
* Add support for potentially failed state.
* Bring back RTO.min to 1 second.
* Accept packets on IP-addresses already announced via an ASCONF
* While there: do some cleanups.
Approved by: re@
MFC after: 2 months.
right mix. Still may need some tweaks but it
appears to almost not give away too much to an
RFC2581 flow, but can really minimize the amount of
buffers used in the net.
MFC after: 3 months
1) Add four new points that allow you to get more information
to cc algo's
2) Fix the case where user changes module on a existing TCB, in
such a case, the initialization module needs to be called on all nets.
3) Move htcp_cc structure to a union that other modules can use.
4) Add 5th point for get/set socket options for cc_module specific options
MFC after: 2 months
2) Add separate max-bursts for retransmit and hb. These
are set to sysctlable values but not settable via the
socket api. This makes sure we don't blast out HB's or
fast-retransmits.
3) Determine on the first data transmission on a net if
its local-lan (by being under or over a RTT). This
can later be used to think about different algorithms
based on locallan vs big-i (experimental)
4) The cwnd should NOT be allowed to grow when an ECNEcho
is seen (TCP has this same bug). We fix this in SCTP
so an ECNe being seen prevents an advance of cwnd.
5) CWR's should not be sent multiple times to the
same network, instead just updating the TSN being
transmitted if needed.
MFC after: 1 Month
1) We now remove ECN-Nonce since it will no longer continue as a I-D
2) Eliminate last_tsn_echo, this tied us to an assoc not the net
and thus we were not doing m-homing on the ECN-Echo senders side right.
3) Increment the count going out even if the TSN in lower in the pending
ECN-Echo, this way the receiver knows exactly how many packets were
marked even with network re-ordering
4) Fix so we DO NOT stop doing delayed sack if a ECN Echo is in queue
MFC after: 1 month
1) ECN was on an association basis, this is incorrect and
will not work with CMT or for that matter if the user
is sending to multiple addresses. This commit makes
ECN on a per path basis.
2) Adopt the new format for the ECN internet draft. This also
maintains compatability with old format chunks as well.
3) Keep track of the real time of a RTT down to micro seconds.
For some future conditional features (for like a data center
this is good information to have).
MFC after: 1 month
