/*
* This implementation should follow RFC 4341
*/
-
+#include "../feat.h"
#include "../ccid.h"
#include "../dccp.h"
#include "ccid2.h"
#ifdef CONFIG_IP_DCCP_CCID2_DEBUG
static int ccid2_debug;
#define ccid2_pr_debug(format, a...) DCCP_PR_DEBUG(ccid2_debug, format, ##a)
-
-static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx)
-{
- int len = 0;
- int pipe = 0;
- struct ccid2_seq *seqp = hctx->ccid2hctx_seqh;
-
- /* there is data in the chain */
- if (seqp != hctx->ccid2hctx_seqt) {
- seqp = seqp->ccid2s_prev;
- len++;
- if (!seqp->ccid2s_acked)
- pipe++;
-
- while (seqp != hctx->ccid2hctx_seqt) {
- struct ccid2_seq *prev = seqp->ccid2s_prev;
-
- len++;
- if (!prev->ccid2s_acked)
- pipe++;
-
- /* packets are sent sequentially */
- BUG_ON(dccp_delta_seqno(seqp->ccid2s_seq,
- prev->ccid2s_seq ) >= 0);
- BUG_ON(time_before(seqp->ccid2s_sent,
- prev->ccid2s_sent));
-
- seqp = prev;
- }
- }
-
- BUG_ON(pipe != hctx->ccid2hctx_pipe);
- ccid2_pr_debug("len of chain=%d\n", len);
-
- do {
- seqp = seqp->ccid2s_prev;
- len++;
- } while (seqp != hctx->ccid2hctx_seqh);
-
- ccid2_pr_debug("total len=%d\n", len);
- BUG_ON(len != hctx->ccid2hctx_seqbufc * CCID2_SEQBUF_LEN);
-}
#else
#define ccid2_pr_debug(format, a...)
-#define ccid2_hc_tx_check_sanity(hctx)
#endif
static int ccid2_hc_tx_alloc_seq(struct ccid2_hc_tx_sock *hctx)
int i;
/* check if we have space to preserve the pointer to the buffer */
- if (hctx->ccid2hctx_seqbufc >= (sizeof(hctx->ccid2hctx_seqbuf) /
- sizeof(struct ccid2_seq*)))
+ if (hctx->seqbufc >= sizeof(hctx->seqbuf) / sizeof(struct ccid2_seq *))
return -ENOMEM;
/* allocate buffer and initialize linked list */
seqp->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1];
/* This is the first allocation. Initiate the head and tail. */
- if (hctx->ccid2hctx_seqbufc == 0)
- hctx->ccid2hctx_seqh = hctx->ccid2hctx_seqt = seqp;
+ if (hctx->seqbufc == 0)
+ hctx->seqh = hctx->seqt = seqp;
else {
/* link the existing list with the one we just created */
- hctx->ccid2hctx_seqh->ccid2s_next = seqp;
- seqp->ccid2s_prev = hctx->ccid2hctx_seqh;
+ hctx->seqh->ccid2s_next = seqp;
+ seqp->ccid2s_prev = hctx->seqh;
- hctx->ccid2hctx_seqt->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1];
- seqp[CCID2_SEQBUF_LEN - 1].ccid2s_next = hctx->ccid2hctx_seqt;
+ hctx->seqt->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1];
+ seqp[CCID2_SEQBUF_LEN - 1].ccid2s_next = hctx->seqt;
}
/* store the original pointer to the buffer so we can free it */
- hctx->ccid2hctx_seqbuf[hctx->ccid2hctx_seqbufc] = seqp;
- hctx->ccid2hctx_seqbufc++;
+ hctx->seqbuf[hctx->seqbufc] = seqp;
+ hctx->seqbufc++;
return 0;
}
static int ccid2_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
{
- struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
-
- if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd)
- return 0;
-
- return 1; /* XXX CCID should dequeue when ready instead of polling */
+ if (ccid2_cwnd_network_limited(ccid2_hc_tx_sk(sk)))
+ return CCID_PACKET_WILL_DEQUEUE_LATER;
+ return CCID_PACKET_SEND_AT_ONCE;
}
static void ccid2_change_l_ack_ratio(struct sock *sk, u32 val)
{
struct dccp_sock *dp = dccp_sk(sk);
- u32 max_ratio = DIV_ROUND_UP(ccid2_hc_tx_sk(sk)->ccid2hctx_cwnd, 2);
+ u32 max_ratio = DIV_ROUND_UP(ccid2_hc_tx_sk(sk)->cwnd, 2);
/*
* Ensure that Ack Ratio does not exceed ceil(cwnd/2), which is (2) from
DCCP_WARN("Limiting Ack Ratio (%u) to %u\n", val, max_ratio);
val = max_ratio;
}
- if (val > 0xFFFF) /* RFC 4340, 11.3 */
- val = 0xFFFF;
+ if (val > DCCPF_ACK_RATIO_MAX)
+ val = DCCPF_ACK_RATIO_MAX;
if (val == dp->dccps_l_ack_ratio)
return;
dp->dccps_l_ack_ratio = val;
}
-static void ccid2_change_srtt(struct ccid2_hc_tx_sock *hctx, long val)
-{
- ccid2_pr_debug("change SRTT to %ld\n", val);
- hctx->ccid2hctx_srtt = val;
-}
-
-static void ccid2_start_rto_timer(struct sock *sk);
-
static void ccid2_hc_tx_rto_expire(unsigned long data)
{
struct sock *sk = (struct sock *)data;
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- long s;
+ const bool sender_was_blocked = ccid2_cwnd_network_limited(hctx);
bh_lock_sock(sk);
if (sock_owned_by_user(sk)) {
- sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer,
- jiffies + HZ / 5);
+ sk_reset_timer(sk, &hctx->rtotimer, jiffies + HZ / 5);
goto out;
}
ccid2_pr_debug("RTO_EXPIRE\n");
- ccid2_hc_tx_check_sanity(hctx);
-
/* back-off timer */
- hctx->ccid2hctx_rto <<= 1;
-
- s = hctx->ccid2hctx_rto / HZ;
- if (s > 60)
- hctx->ccid2hctx_rto = 60 * HZ;
-
- ccid2_start_rto_timer(sk);
+ hctx->rto <<= 1;
+ if (hctx->rto > DCCP_RTO_MAX)
+ hctx->rto = DCCP_RTO_MAX;
/* adjust pipe, cwnd etc */
- hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd / 2;
- if (hctx->ccid2hctx_ssthresh < 2)
- hctx->ccid2hctx_ssthresh = 2;
- hctx->ccid2hctx_cwnd = 1;
- hctx->ccid2hctx_pipe = 0;
+ hctx->ssthresh = hctx->cwnd / 2;
+ if (hctx->ssthresh < 2)
+ hctx->ssthresh = 2;
+ hctx->cwnd = 1;
+ hctx->pipe = 0;
/* clear state about stuff we sent */
- hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
- hctx->ccid2hctx_packets_acked = 0;
+ hctx->seqt = hctx->seqh;
+ hctx->packets_acked = 0;
/* clear ack ratio state. */
- hctx->ccid2hctx_rpseq = 0;
- hctx->ccid2hctx_rpdupack = -1;
+ hctx->rpseq = 0;
+ hctx->rpdupack = -1;
ccid2_change_l_ack_ratio(sk, 1);
- ccid2_hc_tx_check_sanity(hctx);
+
+ /* if we were blocked before, we may now send cwnd=1 packet */
+ if (sender_was_blocked)
+ tasklet_schedule(&dccp_sk(sk)->dccps_xmitlet);
+ /* restart backed-off timer */
+ sk_reset_timer(sk, &hctx->rtotimer, jiffies + hctx->rto);
out:
bh_unlock_sock(sk);
sock_put(sk);
}
-static void ccid2_start_rto_timer(struct sock *sk)
-{
- struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
-
- ccid2_pr_debug("setting RTO timeout=%ld\n", hctx->ccid2hctx_rto);
-
- BUG_ON(timer_pending(&hctx->ccid2hctx_rtotimer));
- sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer,
- jiffies + hctx->ccid2hctx_rto);
-}
-
-static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
+static void ccid2_hc_tx_packet_sent(struct sock *sk, unsigned int len)
{
struct dccp_sock *dp = dccp_sk(sk);
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
struct ccid2_seq *next;
- hctx->ccid2hctx_pipe++;
+ hctx->pipe++;
- hctx->ccid2hctx_seqh->ccid2s_seq = dp->dccps_gss;
- hctx->ccid2hctx_seqh->ccid2s_acked = 0;
- hctx->ccid2hctx_seqh->ccid2s_sent = jiffies;
+ hctx->seqh->ccid2s_seq = dp->dccps_gss;
+ hctx->seqh->ccid2s_acked = 0;
+ hctx->seqh->ccid2s_sent = jiffies;
- next = hctx->ccid2hctx_seqh->ccid2s_next;
+ next = hctx->seqh->ccid2s_next;
/* check if we need to alloc more space */
- if (next == hctx->ccid2hctx_seqt) {
+ if (next == hctx->seqt) {
if (ccid2_hc_tx_alloc_seq(hctx)) {
DCCP_CRIT("packet history - out of memory!");
/* FIXME: find a more graceful way to bail out */
return;
}
- next = hctx->ccid2hctx_seqh->ccid2s_next;
- BUG_ON(next == hctx->ccid2hctx_seqt);
+ next = hctx->seqh->ccid2s_next;
+ BUG_ON(next == hctx->seqt);
}
- hctx->ccid2hctx_seqh = next;
+ hctx->seqh = next;
- ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->ccid2hctx_cwnd,
- hctx->ccid2hctx_pipe);
+ ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->cwnd, hctx->pipe);
/*
* FIXME: The code below is broken and the variables have been removed
*/
#if 0
/* Ack Ratio. Need to maintain a concept of how many windows we sent */
- hctx->ccid2hctx_arsent++;
+ hctx->arsent++;
/* We had an ack loss in this window... */
- if (hctx->ccid2hctx_ackloss) {
- if (hctx->ccid2hctx_arsent >= hctx->ccid2hctx_cwnd) {
- hctx->ccid2hctx_arsent = 0;
- hctx->ccid2hctx_ackloss = 0;
+ if (hctx->ackloss) {
+ if (hctx->arsent >= hctx->cwnd) {
+ hctx->arsent = 0;
+ hctx->ackloss = 0;
}
} else {
/* No acks lost up to now... */
int denom = dp->dccps_l_ack_ratio * dp->dccps_l_ack_ratio -
dp->dccps_l_ack_ratio;
- denom = hctx->ccid2hctx_cwnd * hctx->ccid2hctx_cwnd / denom;
+ denom = hctx->cwnd * hctx->cwnd / denom;
- if (hctx->ccid2hctx_arsent >= denom) {
+ if (hctx->arsent >= denom) {
ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio - 1);
- hctx->ccid2hctx_arsent = 0;
+ hctx->arsent = 0;
}
} else {
/* we can't increase ack ratio further [1] */
- hctx->ccid2hctx_arsent = 0; /* or maybe set it to cwnd*/
+ hctx->arsent = 0; /* or maybe set it to cwnd*/
}
}
#endif
/* setup RTO timer */
- if (!timer_pending(&hctx->ccid2hctx_rtotimer))
- ccid2_start_rto_timer(sk);
+ if (!timer_pending(&hctx->rtotimer))
+ sk_reset_timer(sk, &hctx->rtotimer, jiffies + hctx->rto);
#ifdef CONFIG_IP_DCCP_CCID2_DEBUG
do {
- struct ccid2_seq *seqp = hctx->ccid2hctx_seqt;
+ struct ccid2_seq *seqp = hctx->seqt;
- while (seqp != hctx->ccid2hctx_seqh) {
+ while (seqp != hctx->seqh) {
ccid2_pr_debug("out seq=%llu acked=%d time=%lu\n",
(unsigned long long)seqp->ccid2s_seq,
seqp->ccid2s_acked, seqp->ccid2s_sent);
}
} while (0);
ccid2_pr_debug("=========\n");
- ccid2_hc_tx_check_sanity(hctx);
#endif
}
-/* XXX Lame code duplication!
- * returns -1 if none was found.
- * else returns the next offset to use in the function call.
+/**
+ * ccid2_rtt_estimator - Sample RTT and compute RTO using RFC2988 algorithm
+ * This code is almost identical with TCP's tcp_rtt_estimator(), since
+ * - it has a higher sampling frequency (recommended by RFC 1323),
+ * - the RTO does not collapse into RTT due to RTTVAR going towards zero,
+ * - it is simple (cf. more complex proposals such as Eifel timer or research
+ * which suggests that the gain should be set according to window size),
+ * - in tests it was found to work well with CCID2 [gerrit].
*/
-static int ccid2_ackvector(struct sock *sk, struct sk_buff *skb, int offset,
- unsigned char **vec, unsigned char *veclen)
+static void ccid2_rtt_estimator(struct sock *sk, const long mrtt)
{
- const struct dccp_hdr *dh = dccp_hdr(skb);
- unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
- unsigned char *opt_ptr;
- const unsigned char *opt_end = (unsigned char *)dh +
- (dh->dccph_doff * 4);
- unsigned char opt, len;
- unsigned char *value;
-
- BUG_ON(offset < 0);
- options += offset;
- opt_ptr = options;
- if (opt_ptr >= opt_end)
- return -1;
-
- while (opt_ptr != opt_end) {
- opt = *opt_ptr++;
- len = 0;
- value = NULL;
-
- /* Check if this isn't a single byte option */
- if (opt > DCCPO_MAX_RESERVED) {
- if (opt_ptr == opt_end)
- goto out_invalid_option;
-
- len = *opt_ptr++;
- if (len < 3)
- goto out_invalid_option;
+ struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
+ long m = mrtt ? : 1;
+
+ if (hctx->srtt == 0) {
+ /* First measurement m */
+ hctx->srtt = m << 3;
+ hctx->mdev = m << 1;
+
+ hctx->mdev_max = max(TCP_RTO_MIN, hctx->mdev);
+ hctx->rttvar = hctx->mdev_max;
+ hctx->rtt_seq = dccp_sk(sk)->dccps_gss;
+ } else {
+ /* Update scaled SRTT as SRTT += 1/8 * (m - SRTT) */
+ m -= (hctx->srtt >> 3);
+ hctx->srtt += m;
+
+ /* Similarly, update scaled mdev with regard to |m| */
+ if (m < 0) {
+ m = -m;
+ m -= (hctx->mdev >> 2);
/*
- * Remove the type and len fields, leaving
- * just the value size
+ * This neutralises RTO increase when RTT < SRTT - mdev
+ * (see P. Sarolahti, A. Kuznetsov,"Congestion Control
+ * in Linux TCP", USENIX 2002, pp. 49-62).
*/
- len -= 2;
- value = opt_ptr;
- opt_ptr += len;
+ if (m > 0)
+ m >>= 3;
+ } else {
+ m -= (hctx->mdev >> 2);
+ }
+ hctx->mdev += m;
- if (opt_ptr > opt_end)
- goto out_invalid_option;
+ if (hctx->mdev > hctx->mdev_max) {
+ hctx->mdev_max = hctx->mdev;
+ if (hctx->mdev_max > hctx->rttvar)
+ hctx->rttvar = hctx->mdev_max;
}
- switch (opt) {
- case DCCPO_ACK_VECTOR_0:
- case DCCPO_ACK_VECTOR_1:
- *vec = value;
- *veclen = len;
- return offset + (opt_ptr - options);
+ /*
+ * Decay RTTVAR at most once per flight, exploiting that
+ * 1) pipe <= cwnd <= Sequence_Window = W (RFC 4340, 7.5.2)
+ * 2) AWL = GSS-W+1 <= GAR <= GSS (RFC 4340, 7.5.1)
+ * GAR is a useful bound for FlightSize = pipe, AWL is probably
+ * too low as it over-estimates pipe.
+ */
+ if (after48(dccp_sk(sk)->dccps_gar, hctx->rtt_seq)) {
+ if (hctx->mdev_max < hctx->rttvar)
+ hctx->rttvar -= (hctx->rttvar -
+ hctx->mdev_max) >> 2;
+ hctx->rtt_seq = dccp_sk(sk)->dccps_gss;
+ hctx->mdev_max = TCP_RTO_MIN;
}
}
- return -1;
-
-out_invalid_option:
- DCCP_BUG("Invalid option - this should not happen (previous parsing)!");
- return -1;
-}
-
-static void ccid2_hc_tx_kill_rto_timer(struct sock *sk)
-{
- struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
+ /*
+ * Set RTO from SRTT and RTTVAR
+ * Clock granularity is ignored since the minimum error for RTTVAR is
+ * clamped to 50msec (corresponding to HZ=20). This leads to a minimum
+ * RTO of 200msec. This agrees with TCP and RFC 4341, 5.: "Because DCCP
+ * does not retransmit data, DCCP does not require TCP's recommended
+ * minimum timeout of one second".
+ */
+ hctx->rto = (hctx->srtt >> 3) + hctx->rttvar;
- sk_stop_timer(sk, &hctx->ccid2hctx_rtotimer);
- ccid2_pr_debug("deleted RTO timer\n");
+ if (hctx->rto > DCCP_RTO_MAX)
+ hctx->rto = DCCP_RTO_MAX;
}
-static inline void ccid2_new_ack(struct sock *sk,
- struct ccid2_seq *seqp,
- unsigned int *maxincr)
+static void ccid2_new_ack(struct sock *sk, struct ccid2_seq *seqp,
+ unsigned int *maxincr)
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh) {
- if (*maxincr > 0 && ++hctx->ccid2hctx_packets_acked == 2) {
- hctx->ccid2hctx_cwnd += 1;
- *maxincr -= 1;
- hctx->ccid2hctx_packets_acked = 0;
+ if (hctx->cwnd < hctx->ssthresh) {
+ if (*maxincr > 0 && ++hctx->packets_acked == 2) {
+ hctx->cwnd += 1;
+ *maxincr -= 1;
+ hctx->packets_acked = 0;
}
- } else if (++hctx->ccid2hctx_packets_acked >= hctx->ccid2hctx_cwnd) {
- hctx->ccid2hctx_cwnd += 1;
- hctx->ccid2hctx_packets_acked = 0;
+ } else if (++hctx->packets_acked >= hctx->cwnd) {
+ hctx->cwnd += 1;
+ hctx->packets_acked = 0;
}
-
- /* update RTO */
- if (hctx->ccid2hctx_srtt == -1 ||
- time_after(jiffies, hctx->ccid2hctx_lastrtt + hctx->ccid2hctx_srtt)) {
- unsigned long r = (long)jiffies - (long)seqp->ccid2s_sent;
- int s;
-
- /* first measurement */
- if (hctx->ccid2hctx_srtt == -1) {
- ccid2_pr_debug("R: %lu Time=%lu seq=%llu\n",
- r, jiffies,
- (unsigned long long)seqp->ccid2s_seq);
- ccid2_change_srtt(hctx, r);
- hctx->ccid2hctx_rttvar = r >> 1;
- } else {
- /* RTTVAR */
- long tmp = hctx->ccid2hctx_srtt - r;
- long srtt;
-
- if (tmp < 0)
- tmp *= -1;
-
- tmp >>= 2;
- hctx->ccid2hctx_rttvar *= 3;
- hctx->ccid2hctx_rttvar >>= 2;
- hctx->ccid2hctx_rttvar += tmp;
-
- /* SRTT */
- srtt = hctx->ccid2hctx_srtt;
- srtt *= 7;
- srtt >>= 3;
- tmp = r >> 3;
- srtt += tmp;
- ccid2_change_srtt(hctx, srtt);
- }
- s = hctx->ccid2hctx_rttvar << 2;
- /* clock granularity is 1 when based on jiffies */
- if (!s)
- s = 1;
- hctx->ccid2hctx_rto = hctx->ccid2hctx_srtt + s;
-
- /* must be at least a second */
- s = hctx->ccid2hctx_rto / HZ;
- /* DCCP doesn't require this [but I like it cuz my code sux] */
-#if 1
- if (s < 1)
- hctx->ccid2hctx_rto = HZ;
-#endif
- /* max 60 seconds */
- if (s > 60)
- hctx->ccid2hctx_rto = HZ * 60;
-
- hctx->ccid2hctx_lastrtt = jiffies;
-
- ccid2_pr_debug("srtt: %ld rttvar: %ld rto: %ld (HZ=%d) R=%lu\n",
- hctx->ccid2hctx_srtt, hctx->ccid2hctx_rttvar,
- hctx->ccid2hctx_rto, HZ, r);
- }
-
- /* we got a new ack, so re-start RTO timer */
- ccid2_hc_tx_kill_rto_timer(sk);
- ccid2_start_rto_timer(sk);
-}
-
-static void ccid2_hc_tx_dec_pipe(struct sock *sk)
-{
- struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
-
- if (hctx->ccid2hctx_pipe == 0)
- DCCP_BUG("pipe == 0");
- else
- hctx->ccid2hctx_pipe--;
-
- if (hctx->ccid2hctx_pipe == 0)
- ccid2_hc_tx_kill_rto_timer(sk);
+ /*
+ * FIXME: RTT is sampled several times per acknowledgment (for each
+ * entry in the Ack Vector), instead of once per Ack (as in TCP SACK).
+ * This causes the RTT to be over-estimated, since the older entries
+ * in the Ack Vector have earlier sending times.
+ * The cleanest solution is to not use the ccid2s_sent field at all
+ * and instead use DCCP timestamps - need to be resolved at some time.
+ */
+ ccid2_rtt_estimator(sk, jiffies - seqp->ccid2s_sent);
}
static void ccid2_congestion_event(struct sock *sk, struct ccid2_seq *seqp)
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- if (time_before(seqp->ccid2s_sent, hctx->ccid2hctx_last_cong)) {
+ if (time_before(seqp->ccid2s_sent, hctx->last_cong)) {
ccid2_pr_debug("Multiple losses in an RTT---treating as one\n");
return;
}
- hctx->ccid2hctx_last_cong = jiffies;
+ hctx->last_cong = jiffies;
- hctx->ccid2hctx_cwnd = hctx->ccid2hctx_cwnd / 2 ? : 1U;
- hctx->ccid2hctx_ssthresh = max(hctx->ccid2hctx_cwnd, 2U);
+ hctx->cwnd = hctx->cwnd / 2 ? : 1U;
+ hctx->ssthresh = max(hctx->cwnd, 2U);
/* Avoid spurious timeouts resulting from Ack Ratio > cwnd */
- if (dccp_sk(sk)->dccps_l_ack_ratio > hctx->ccid2hctx_cwnd)
- ccid2_change_l_ack_ratio(sk, hctx->ccid2hctx_cwnd);
+ if (dccp_sk(sk)->dccps_l_ack_ratio > hctx->cwnd)
+ ccid2_change_l_ack_ratio(sk, hctx->cwnd);
+}
+
+static int ccid2_hc_tx_parse_options(struct sock *sk, u8 packet_type,
+ u8 option, u8 *optval, u8 optlen)
+{
+ struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
+
+ switch (option) {
+ case DCCPO_ACK_VECTOR_0:
+ case DCCPO_ACK_VECTOR_1:
+ return dccp_ackvec_parsed_add(&hctx->av_chunks, optval, optlen,
+ option - DCCPO_ACK_VECTOR_0);
+ }
+ return 0;
}
static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
+ const bool sender_was_blocked = ccid2_cwnd_network_limited(hctx);
+ struct dccp_ackvec_parsed *avp;
u64 ackno, seqno;
struct ccid2_seq *seqp;
- unsigned char *vector;
- unsigned char veclen;
- int offset = 0;
int done = 0;
unsigned int maxincr = 0;
- ccid2_hc_tx_check_sanity(hctx);
/* check reverse path congestion */
seqno = DCCP_SKB_CB(skb)->dccpd_seq;
* -sorbo.
*/
/* need to bootstrap */
- if (hctx->ccid2hctx_rpdupack == -1) {
- hctx->ccid2hctx_rpdupack = 0;
- hctx->ccid2hctx_rpseq = seqno;
+ if (hctx->rpdupack == -1) {
+ hctx->rpdupack = 0;
+ hctx->rpseq = seqno;
} else {
/* check if packet is consecutive */
- if (dccp_delta_seqno(hctx->ccid2hctx_rpseq, seqno) == 1)
- hctx->ccid2hctx_rpseq = seqno;
+ if (dccp_delta_seqno(hctx->rpseq, seqno) == 1)
+ hctx->rpseq = seqno;
/* it's a later packet */
- else if (after48(seqno, hctx->ccid2hctx_rpseq)) {
- hctx->ccid2hctx_rpdupack++;
+ else if (after48(seqno, hctx->rpseq)) {
+ hctx->rpdupack++;
/* check if we got enough dupacks */
- if (hctx->ccid2hctx_rpdupack >= NUMDUPACK) {
- hctx->ccid2hctx_rpdupack = -1; /* XXX lame */
- hctx->ccid2hctx_rpseq = 0;
+ if (hctx->rpdupack >= NUMDUPACK) {
+ hctx->rpdupack = -1; /* XXX lame */
+ hctx->rpseq = 0;
ccid2_change_l_ack_ratio(sk, 2 * dp->dccps_l_ack_ratio);
}
}
/* check forward path congestion */
- /* still didn't send out new data packets */
- if (hctx->ccid2hctx_seqh == hctx->ccid2hctx_seqt)
+ if (dccp_packet_without_ack(skb))
return;
- switch (DCCP_SKB_CB(skb)->dccpd_type) {
- case DCCP_PKT_ACK:
- case DCCP_PKT_DATAACK:
- break;
- default:
- return;
- }
+ /* still didn't send out new data packets */
+ if (hctx->seqh == hctx->seqt)
+ goto done;
ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
- if (after48(ackno, hctx->ccid2hctx_high_ack))
- hctx->ccid2hctx_high_ack = ackno;
+ if (after48(ackno, hctx->high_ack))
+ hctx->high_ack = ackno;
- seqp = hctx->ccid2hctx_seqt;
+ seqp = hctx->seqt;
while (before48(seqp->ccid2s_seq, ackno)) {
seqp = seqp->ccid2s_next;
- if (seqp == hctx->ccid2hctx_seqh) {
- seqp = hctx->ccid2hctx_seqh->ccid2s_prev;
+ if (seqp == hctx->seqh) {
+ seqp = hctx->seqh->ccid2s_prev;
break;
}
}
* packets per acknowledgement. Rounding up avoids that cwnd is not
* advanced when Ack Ratio is 1 and gives a slight edge otherwise.
*/
- if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh)
+ if (hctx->cwnd < hctx->ssthresh)
maxincr = DIV_ROUND_UP(dp->dccps_l_ack_ratio, 2);
/* go through all ack vectors */
- while ((offset = ccid2_ackvector(sk, skb, offset,
- &vector, &veclen)) != -1) {
+ list_for_each_entry(avp, &hctx->av_chunks, node) {
/* go through this ack vector */
- while (veclen--) {
- const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
- u64 ackno_end_rl = SUB48(ackno, rl);
+ for (; avp->len--; avp->vec++) {
+ u64 ackno_end_rl = SUB48(ackno,
+ dccp_ackvec_runlen(avp->vec));
- ccid2_pr_debug("ackvec start:%llu end:%llu\n",
+ ccid2_pr_debug("ackvec %llu |%u,%u|\n",
(unsigned long long)ackno,
- (unsigned long long)ackno_end_rl);
+ dccp_ackvec_state(avp->vec) >> 6,
+ dccp_ackvec_runlen(avp->vec));
/* if the seqno we are analyzing is larger than the
* current ackno, then move towards the tail of our
* seqnos.
*/
while (after48(seqp->ccid2s_seq, ackno)) {
- if (seqp == hctx->ccid2hctx_seqt) {
+ if (seqp == hctx->seqt) {
done = 1;
break;
}
* run length
*/
while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) {
- const u8 state = *vector &
- DCCP_ACKVEC_STATE_MASK;
+ const u8 state = dccp_ackvec_state(avp->vec);
/* new packet received or marked */
- if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED &&
+ if (state != DCCPAV_NOT_RECEIVED &&
!seqp->ccid2s_acked) {
- if (state ==
- DCCP_ACKVEC_STATE_ECN_MARKED) {
+ if (state == DCCPAV_ECN_MARKED)
ccid2_congestion_event(sk,
seqp);
- } else
+ else
ccid2_new_ack(sk, seqp,
&maxincr);
seqp->ccid2s_acked = 1;
ccid2_pr_debug("Got ack for %llu\n",
(unsigned long long)seqp->ccid2s_seq);
- ccid2_hc_tx_dec_pipe(sk);
+ hctx->pipe--;
}
- if (seqp == hctx->ccid2hctx_seqt) {
+ if (seqp == hctx->seqt) {
done = 1;
break;
}
break;
ackno = SUB48(ackno_end_rl, 1);
- vector++;
}
if (done)
break;
/* The state about what is acked should be correct now
* Check for NUMDUPACK
*/
- seqp = hctx->ccid2hctx_seqt;
- while (before48(seqp->ccid2s_seq, hctx->ccid2hctx_high_ack)) {
+ seqp = hctx->seqt;
+ while (before48(seqp->ccid2s_seq, hctx->high_ack)) {
seqp = seqp->ccid2s_next;
- if (seqp == hctx->ccid2hctx_seqh) {
- seqp = hctx->ccid2hctx_seqh->ccid2s_prev;
+ if (seqp == hctx->seqh) {
+ seqp = hctx->seqh->ccid2s_prev;
break;
}
}
if (done == NUMDUPACK)
break;
}
- if (seqp == hctx->ccid2hctx_seqt)
+ if (seqp == hctx->seqt)
break;
seqp = seqp->ccid2s_prev;
}
* one ack vector.
*/
ccid2_congestion_event(sk, seqp);
- ccid2_hc_tx_dec_pipe(sk);
+ hctx->pipe--;
}
- if (seqp == hctx->ccid2hctx_seqt)
+ if (seqp == hctx->seqt)
break;
seqp = seqp->ccid2s_prev;
}
- hctx->ccid2hctx_seqt = last_acked;
+ hctx->seqt = last_acked;
}
/* trim acked packets in tail */
- while (hctx->ccid2hctx_seqt != hctx->ccid2hctx_seqh) {
- if (!hctx->ccid2hctx_seqt->ccid2s_acked)
+ while (hctx->seqt != hctx->seqh) {
+ if (!hctx->seqt->ccid2s_acked)
break;
- hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqt->ccid2s_next;
+ hctx->seqt = hctx->seqt->ccid2s_next;
}
- ccid2_hc_tx_check_sanity(hctx);
+ /* restart RTO timer if not all outstanding data has been acked */
+ if (hctx->pipe == 0)
+ sk_stop_timer(sk, &hctx->rtotimer);
+ else
+ sk_reset_timer(sk, &hctx->rtotimer, jiffies + hctx->rto);
+done:
+ /* check if incoming Acks allow pending packets to be sent */
+ if (sender_was_blocked && !ccid2_cwnd_network_limited(hctx))
+ tasklet_schedule(&dccp_sk(sk)->dccps_xmitlet);
+ dccp_ackvec_parsed_cleanup(&hctx->av_chunks);
}
static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk)
u32 max_ratio;
/* RFC 4341, 5: initialise ssthresh to arbitrarily high (max) value */
- hctx->ccid2hctx_ssthresh = ~0U;
+ hctx->ssthresh = ~0U;
- /*
- * RFC 4341, 5: "The cwnd parameter is initialized to at most four
- * packets for new connections, following the rules from [RFC3390]".
- * We need to convert the bytes of RFC3390 into the packets of RFC 4341.
- */
- hctx->ccid2hctx_cwnd = min(4U, max(2U, 4380U / dp->dccps_mss_cache));
+ /* Use larger initial windows (RFC 3390, rfc2581bis) */
+ hctx->cwnd = rfc3390_bytes_to_packets(dp->dccps_mss_cache);
/* Make sure that Ack Ratio is enabled and within bounds. */
- max_ratio = DIV_ROUND_UP(hctx->ccid2hctx_cwnd, 2);
+ max_ratio = DIV_ROUND_UP(hctx->cwnd, 2);
if (dp->dccps_l_ack_ratio == 0 || dp->dccps_l_ack_ratio > max_ratio)
dp->dccps_l_ack_ratio = max_ratio;
if (ccid2_hc_tx_alloc_seq(hctx))
return -ENOMEM;
- hctx->ccid2hctx_rto = 3 * HZ;
- ccid2_change_srtt(hctx, -1);
- hctx->ccid2hctx_rttvar = -1;
- hctx->ccid2hctx_rpdupack = -1;
- hctx->ccid2hctx_last_cong = jiffies;
- setup_timer(&hctx->ccid2hctx_rtotimer, ccid2_hc_tx_rto_expire,
- (unsigned long)sk);
-
- ccid2_hc_tx_check_sanity(hctx);
+ hctx->rto = DCCP_TIMEOUT_INIT;
+ hctx->rpdupack = -1;
+ hctx->last_cong = jiffies;
+ setup_timer(&hctx->rtotimer, ccid2_hc_tx_rto_expire, (unsigned long)sk);
+ INIT_LIST_HEAD(&hctx->av_chunks);
return 0;
}
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
int i;
- ccid2_hc_tx_kill_rto_timer(sk);
+ sk_stop_timer(sk, &hctx->rtotimer);
- for (i = 0; i < hctx->ccid2hctx_seqbufc; i++)
- kfree(hctx->ccid2hctx_seqbuf[i]);
- hctx->ccid2hctx_seqbufc = 0;
+ for (i = 0; i < hctx->seqbufc; i++)
+ kfree(hctx->seqbuf[i]);
+ hctx->seqbufc = 0;
}
static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
switch (DCCP_SKB_CB(skb)->dccpd_type) {
case DCCP_PKT_DATA:
case DCCP_PKT_DATAACK:
- hcrx->ccid2hcrx_data++;
- if (hcrx->ccid2hcrx_data >= dp->dccps_r_ack_ratio) {
+ hcrx->data++;
+ if (hcrx->data >= dp->dccps_r_ack_ratio) {
dccp_send_ack(sk);
- hcrx->ccid2hcrx_data = 0;
+ hcrx->data = 0;
}
break;
}
}
static struct ccid_operations ccid2 = {
- .ccid_id = DCCPC_CCID2,
- .ccid_name = "TCP-like",
- .ccid_owner = THIS_MODULE,
- .ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock),
- .ccid_hc_tx_init = ccid2_hc_tx_init,
- .ccid_hc_tx_exit = ccid2_hc_tx_exit,
- .ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet,
- .ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent,
- .ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv,
- .ccid_hc_rx_obj_size = sizeof(struct ccid2_hc_rx_sock),
- .ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv,
+ .ccid_id = DCCPC_CCID2,
+ .ccid_name = "TCP-like",
+ .ccid_owner = THIS_MODULE,
+ .ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock),
+ .ccid_hc_tx_init = ccid2_hc_tx_init,
+ .ccid_hc_tx_exit = ccid2_hc_tx_exit,
+ .ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet,
+ .ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent,
+ .ccid_hc_tx_parse_options = ccid2_hc_tx_parse_options,
+ .ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv,
+ .ccid_hc_rx_obj_size = sizeof(struct ccid2_hc_rx_sock),
+ .ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv,
};
#ifdef CONFIG_IP_DCCP_CCID2_DEBUG
-module_param(ccid2_debug, bool, 0444);
+module_param(ccid2_debug, bool, 0644);
MODULE_PARM_DESC(ccid2_debug, "Enable debug messages");
#endif
projects / linux-2.6-omap-h63xx.git / blobdiff