Move quic_path struct from quic_conn-t.h to quic_cc-t.h and rename it to quic_cc_path.
Update the code consequently.
Also some inlined functions in relation with QUIC path to quic_cc.h
Make all the congestion support the maximum congestion control window
set by configuration. There is nothing special to explain. For each
each algo, each time the window is incremented it is also bounded.
Move all QUIC trace definitions from quic_conn.h to quic_trace-t.h. Also
remove multiple definition trace_quic macro definition into
quic_trace.h. This forces all QUIC source files who relies on trace to
include it while reducing the size of quic_conn.h.
As reported by @Tristan971 in GH #2116, the congestion control window could be zero
due to an inversion in the code about the reduction factor to be applied.
On a new loss event, it must be applied to the slow start threshold and the window
should never be below ->min_cwnd (2*max_udp_payload_sz).
Same issue in both newReno and cubic algorithm. Furthermore in newReno, only the
threshold was decremented.
Must be backported to 2.6 and 2.7.
Add the number of packet losts and the maximum congestion control window computed
by the algorithms to "show quic".
Same thing for the traces of existent congestion control algorithms.
Must be backported to 2.7 and 2.6.
As now_ms may be zero, these BUG_ON() could be triggered when its value has wrapped.
These call to BUG_ON() may be removed because the values they was supposed to
check are safely used by the ticks API.
Must be backported to 2.6 and 2.7.
This very old bug is there since the first implementation of newreno congestion
algorithm implementation. This was a very bad idea to put a state variable
into quic_cc_algo struct which only defines the congestion control algorithm used
by a QUIC listener, typically its type and its callbacks.
This bug could lead to crashes since BUG_ON() calls have been added to each algorithm
implementation. This was revealed by interop test, but not very often as there was
not very often several connections run at the time during these tests.
Hopefully this was also reported by Tristan in GH #2095.
Move the congestion algorithm state to the correct structures which are private
to a connection (see cubic and nr structs).
Must be backported to 2.7 and 2.6.
Dump variables displayed by TRACE_ENTER() or TRACE_LEAVE() by calls to TRACE_PROTO().
No more variables are displayed by the two former macros. For now on, these information
are accessible from proto level.
Add new calls to TRACE_PROTO() at important locations in relation whith QUIC transport
protocol.
When relevant, try to prefix such traces with TX or RX keyword to identify the
concerned subpart (transmission or reception) of the protocol.
Must be backported to 2.7.
This patch is similar to the one for cubic algorithm:
"BUG/MINOR: quic: Wrong use of timestamps with now_ms variable (cubic algo)"
As now_ms may wrap, one must use the ticks API to protect the cubic congestion
control algorithm implementation from side effects due to this.
Furthermore, to make the newreno congestion control algorithm more readable and easy
to maintain, add quic_cc_cubic_rp_cb() new callback for the "in recovery period"
state (QUIC_CC_ST_RP).
Must be backported to 2.7 and 2.6.
xprt_quic module was too large and did not reflect the true architecture
by contrast to the other protocols in haproxy.
Extract code related to XPRT layer and keep it under xprt_quic module.
This code should only contains a simple API to communicate between QUIC
lower layer and connection/MUX.
The vast majority of the code has been moved into a new module named
quic_conn. This module is responsible to the implementation of QUIC
lower layer. Conceptually, it overlaps with TCP kernel implementation
when comparing QUIC and HTTP1/2 stacks of haproxy.
This should be backported up to 2.6.
Clean up quic sources by adjusting headers list included depending
on the actual dependency of each source file.
On some occasion, xprt_quic.h was removed from included list. This is
useful to help reducing the dependency on this single file and cleaning
up QUIC haproxy architecture.
This should be backported up to 2.6.
Ease the integration of new congestion control algorithm to come.
Move the congestion controller state to a private array of uint32_t
to stop using a union. We do not want to continue using such long
paths cc->algo_state.<algo>.<var> to modify the internal state variable
for each algorithm.
Must be backported to 2.6
When in congestion avoidance state and when acknowledging an <acked> number bytes
we must increase the congestion window by at most one datagram (<path->mtu>)
by congestion window. So thanks to this patch we apply a ratio to the current
number of acked bytes : <acked> * <path->mtu> / <cwnd>.
So, when <cwnd> bytes are acked we precisely increment <cwnd> by <path->mtu>.
Furthermore we take into an account the number of remaining acknowledged bytes
each time we increment the window by <acked> storing their values in the algorithm
struct state (->remain_acked) so that it might be take into an account at the
next ACK event.
We establish the persistent congestion out of any congestion controller
to improve the algorithms genericity. This path characteristic detection may
be implemented regarless of the underlying congestion control algorithm.
Send congestion (loss) event using directly quic_cc_event(), so without
qc_cc_loss_event() wrapper function around quic_cc_event().
Take the opportunity of this patch to shorten "newest_time_sent" member field
of quic_cc_event to "time_sent".
We want to be able to make the congestion controllers re-enter the slow
start state outside of the congestion controllers themselves. So,
we add a callback ->slow_start() to do so.
Define this callback for NewReno algorithm.
QUIC connection path in flight bytes is a variable which should not be manipulated
by the congestion controller. This latter aim is to compute the congestion window.
So, we pass it as less as parameters as possible to do so.
As reported by Tim in issue #1428, our sources are clean, there are
just a few files with a few rare non-ASCII chars for the paragraph
symbol, a few typos, or in Fred's name. Given that Fred already uses
the non-accentuated form at other places like on the public list,
let's uniformize all this and make sure the code displays equally
everywhere.
This patch imports all the C files for QUIC protocol implementation with few
modifications from 20200720-quic branch of quic-dev repository found at
https://github.com/haproxytech/quic-dev.
Traces were implemented to help with the development.
