diff options
Diffstat (limited to 'src/ipcpd/unicast/pol/ca-mb-ecn.c')
| -rw-r--r-- | src/ipcpd/unicast/pol/ca-mb-ecn.c | 216 |
1 files changed, 0 insertions, 216 deletions
diff --git a/src/ipcpd/unicast/pol/ca-mb-ecn.c b/src/ipcpd/unicast/pol/ca-mb-ecn.c deleted file mode 100644 index 2de8f8e7..00000000 --- a/src/ipcpd/unicast/pol/ca-mb-ecn.c +++ /dev/null @@ -1,216 +0,0 @@ -/* - * Ouroboros - Copyright (C) 2016 - 2020 - * - * Multi-bit ECN Congestion Avoidance - * - * Dimitri Staessens <dimitri.staessens@ugent.be> - * Sander Vrijders <sander.vrijders@ugent.be> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program 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 General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., http://www.fsf.org/about/contact/. - */ - -#if defined(__linux__) || defined(__CYGWIN__) -#define _DEFAULT_SOURCE -#else -#define _POSIX_C_SOURCE 200809L -#endif - -#include "config.h" - -#include <ouroboros/ipcp-dev.h> -#include <ouroboros/time_utils.h> - -#include "ca-mb-ecn.h" - -#include <stdlib.h> -#include <string.h> - -/* congestion avoidance constants */ -#define CA_SHFT 5 -#define CA_WND (1 << CA_SHFT) -#define CA_UPD (1 << (CA_SHFT - 3)) -#define CA_SLOT 18 -#define CA_AI 20000 -#define ECN_Q_SHFT 5 -#define ts_to_ns(ts) (ts.tv_sec * BILLION + ts.tv_nsec) - -struct mb_ecn_ctx { - uint16_t rx_ece; /* level of congestion (upstream) */ - size_t rx_ctr; /* receiver side packet counter */ - - uint16_t tx_ece; /* level of congestion (downstream) */ - size_t tx_ctr; /* sender side packet counter */ - size_t tx_aps; /* average packet size */ - time_t tx_wnd; /* tgt time to send packets (ns) */ - bool tx_cav; /* Congestion avoidance */ - size_t tx_slot; - - struct timespec t_sent; /* last sent packet */ -}; - -struct pol_ca_ops mb_ecn_ca_ops = { - .ctx_create = mb_ecn_ctx_create, - .ctx_destroy = mb_ecn_ctx_destroy, - .ctx_update_snd = mb_ecn_ctx_update_snd, - .ctx_update_rcv = mb_ecn_ctx_update_rcv, - .ctx_update_ece = mb_ecn_ctx_update_ece, - .wnd_wait = mb_ecn_wnd_wait, - .calc_ecn = mb_ecn_calc_ecn -}; - -void * mb_ecn_ctx_create(void) -{ - - struct mb_ecn_ctx * ctx; - - ctx = malloc(sizeof(*ctx)); - if (ctx == NULL) - return NULL; - - memset(ctx, 0, sizeof(*ctx)); - - return (void *) ctx; -} - -void mb_ecn_ctx_destroy(void * ctx) -{ - free(ctx); -} - -ca_wnd_t mb_ecn_ctx_update_snd(void * _ctx, - size_t len) -{ - struct timespec now; - size_t slot; - time_t gap; - ca_wnd_t wnd; - - struct mb_ecn_ctx * ctx = _ctx; - - clock_gettime(PTHREAD_COND_CLOCK, &now); - - if (ctx->tx_wnd == 0) { /* 10 ms initial window estimate */ - ctx->tx_wnd = 10 * MILLION; - gap = ctx->tx_wnd >> CA_SHFT; - ctx->tx_aps = len >> CA_SHFT; - ctx->tx_slot = ts_to_ns(now) >> CA_SLOT; - } else { - gap = ts_diff_ns(&ctx->t_sent, &now); - ctx->tx_aps -= ctx->tx_aps >> CA_SHFT; - ctx->tx_aps += len; - } - - ctx->t_sent = now; - - slot = ts_to_ns(now) >> CA_SLOT; - - ctx->tx_ctr++; - - if (slot - ctx->tx_slot > 0) { - ctx->tx_slot = slot; - - if (ctx->tx_ctr > CA_WND) - ctx->tx_ece = 0; - - /* Slow start */ - if (!ctx->tx_cav) { - ctx->tx_wnd >>= 1; - /* Multiplicative Decrease */ - } else if (ctx->tx_ece) { /* MD */ - ctx->tx_wnd += (ctx->tx_wnd * ctx->tx_ece) - >> (CA_SHFT + 8); - /* Additive Increase */ - } else { - size_t bw = ctx->tx_aps * BILLION / ctx->tx_wnd; - bw += CA_AI; - ctx->tx_wnd = ctx->tx_aps * BILLION / bw; - } - } - - wnd.wait = (ctx->tx_wnd >> CA_SHFT) - gap; - - return wnd; -} - -void mb_ecn_wnd_wait(ca_wnd_t wnd) -{ - if (wnd.wait > 0) { - struct timespec s = {0, 0}; - if (wnd.wait > BILLION) /* Don't care throttling < 1pps */ - s.tv_sec = 1; - else - s.tv_nsec = wnd.wait; - - nanosleep(&s, NULL); - } -} - -bool mb_ecn_ctx_update_rcv(void * _ctx, - size_t len, - uint8_t ecn, - uint16_t * ece) -{ - struct mb_ecn_ctx* ctx = _ctx; - bool update; - - (void) len; - - if ((ctx->rx_ece | ecn) == 0) - return false; - - if (ecn == 0) { - /* end of congestion */ - ctx->rx_ece >>= 2; - update = ctx->rx_ece == 0; - } else { - if (ctx->rx_ece == 0) { - /* start of congestion */ - ctx->rx_ece = ecn; - ctx->rx_ctr = 0; - update = true; - } else { - /* congestion update */ - ctx->rx_ece -= ctx->rx_ece >> CA_SHFT; - ctx->rx_ece += ecn; - update = (ctx->rx_ctr++ & (CA_UPD - 1)) == true; - } - } - - *ece = ctx->rx_ece; - - return update; -} - - -void mb_ecn_ctx_update_ece(void * _ctx, - uint16_t ece) -{ - struct mb_ecn_ctx* ctx = _ctx; - - ctx->tx_ece = ece; - ctx->tx_ctr = 0; - ctx->tx_cav = true; -} - -uint8_t mb_ecn_calc_ecn(int fd, - size_t len) -{ - size_t q; - - (void) len; - - q = ipcp_flow_queued(fd); - - return (uint8_t) (q >> ECN_Q_SHFT); -} |