diff options
Diffstat (limited to 'src/quic_cc_newreno.c')
| -rw-r--r-- | src/quic_cc_newreno.c | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/src/quic_cc_newreno.c b/src/quic_cc_newreno.c new file mode 100644 index 0000000..e18ba6f --- /dev/null +++ b/src/quic_cc_newreno.c @@ -0,0 +1,173 @@ +/* + * NewReno congestion control algorithm. + * + * This file contains definitions for QUIC congestion control. + * + * Copyright 2019 HAProxy Technologies, Frederic Lecaille <flecaille@haproxy.com> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation, version 2.1 + * exclusively. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <haproxy/api-t.h> +#include <haproxy/buf.h> +#include <haproxy/chunk.h> +#include <haproxy/quic_cc.h> +#include <haproxy/quic_conn-t.h> +#include <haproxy/trace.h> + +#define TRACE_SOURCE &trace_quic + +/* Newreno state */ +struct nr { + uint32_t ssthresh; + uint32_t recovery_start_time; + uint32_t remain_acked; +}; + +static int quic_cc_nr_init(struct quic_cc *cc) +{ + struct nr *nr = quic_cc_priv(cc); + + cc->algo->state = QUIC_CC_ST_SS; + nr->ssthresh = QUIC_CC_INFINITE_SSTHESH; + nr->recovery_start_time = 0; + nr->remain_acked = 0; + + return 1; +} + +/* Re-enter slow start state. */ +static void quic_cc_nr_slow_start(struct quic_cc *cc) +{ + struct quic_path *path; + struct nr *nr = quic_cc_priv(cc); + + path = container_of(cc, struct quic_path, cc); + path->cwnd = path->min_cwnd; + /* Re-entering slow start state. */ + cc->algo->state = QUIC_CC_ST_SS; + /* Recovery start time reset */ + nr->recovery_start_time = 0; +} + +/* Slow start callback. */ +static void quic_cc_nr_ss_cb(struct quic_cc *cc, struct quic_cc_event *ev) +{ + struct quic_path *path; + struct nr *nr = quic_cc_priv(cc); + + TRACE_ENTER(QUIC_EV_CONN_CC, cc->qc, ev); + path = container_of(cc, struct quic_path, cc); + switch (ev->type) { + case QUIC_CC_EVT_ACK: + /* Do not increase the congestion window in recovery period. */ + if (ev->ack.time_sent <= nr->recovery_start_time) + return; + + path->cwnd += ev->ack.acked; + /* Exit to congestion avoidance if slow start threshold is reached. */ + if (path->cwnd > nr->ssthresh) + cc->algo->state = QUIC_CC_ST_CA; + break; + + case QUIC_CC_EVT_LOSS: + path->cwnd = QUIC_MAX(path->cwnd >> 1, path->min_cwnd); + nr->ssthresh = path->cwnd; + /* Exit to congestion avoidance. */ + cc->algo->state = QUIC_CC_ST_CA; + break; + + case QUIC_CC_EVT_ECN_CE: + /* XXX TO DO XXX */ + break; + } + TRACE_LEAVE(QUIC_EV_CONN_CC, cc->qc,, cc); +} + +/* Congestion avoidance callback. */ +static void quic_cc_nr_ca_cb(struct quic_cc *cc, struct quic_cc_event *ev) +{ + struct quic_path *path; + struct nr *nr = quic_cc_priv(cc); + + TRACE_ENTER(QUIC_EV_CONN_CC, cc->qc, ev); + path = container_of(cc, struct quic_path, cc); + switch (ev->type) { + case QUIC_CC_EVT_ACK: + { + uint64_t acked; + /* Do not increase the congestion window in recovery period. */ + if (ev->ack.time_sent <= nr->recovery_start_time) + goto out; + + /* Increasing the congestion window by (acked / cwnd) + */ + acked = ev->ack.acked * path->mtu + nr->remain_acked; + nr->remain_acked = acked % path->cwnd; + path->cwnd += acked / path->cwnd; + break; + } + + case QUIC_CC_EVT_LOSS: + /* Do not decrease the congestion window when already in recovery period. */ + if (ev->loss.time_sent <= nr->recovery_start_time) + goto out; + + nr->recovery_start_time = now_ms; + nr->ssthresh = path->cwnd; + path->cwnd = QUIC_MAX(path->cwnd >> 1, path->min_cwnd); + break; + + case QUIC_CC_EVT_ECN_CE: + /* XXX TO DO XXX */ + break; + } + + out: + TRACE_LEAVE(QUIC_EV_CONN_CC, cc->qc, NULL, cc); +} + +static void quic_cc_nr_state_trace(struct buffer *buf, const struct quic_cc *cc) +{ + struct quic_path *path; + struct nr *nr = quic_cc_priv(cc); + + path = container_of(cc, struct quic_path, cc); + chunk_appendf(buf, " state=%s cwnd=%llu ssthresh=%ld recovery_start_time=%llu", + quic_cc_state_str(cc->algo->state), + (unsigned long long)path->cwnd, + (long)nr->ssthresh, + (unsigned long long)nr->recovery_start_time); +} + +static void (*quic_cc_nr_state_cbs[])(struct quic_cc *cc, + struct quic_cc_event *ev) = { + [QUIC_CC_ST_SS] = quic_cc_nr_ss_cb, + [QUIC_CC_ST_CA] = quic_cc_nr_ca_cb, +}; + +static void quic_cc_nr_event(struct quic_cc *cc, struct quic_cc_event *ev) +{ + return quic_cc_nr_state_cbs[cc->algo->state](cc, ev); +} + +struct quic_cc_algo quic_cc_algo_nr = { + .type = QUIC_CC_ALGO_TP_NEWRENO, + .init = quic_cc_nr_init, + .event = quic_cc_nr_event, + .slow_start = quic_cc_nr_slow_start, + .state_trace = quic_cc_nr_state_trace, +}; + |