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authorJonathan Corbet <corbet@lwn.net>2008-07-14 15:29:34 -0600
committerJonathan Corbet <corbet@lwn.net>2008-07-14 15:29:34 -0600
commit2fceef397f9880b212a74c418290ce69e7ac00eb (patch)
treed9cc09ab992825ef7fede4a688103503e3caf655 /net/sctp/outqueue.c
parentfeae1ef116ed381625d3731c5ae4f4ebcb3fa302 (diff)
parentbce7f793daec3e65ec5c5705d2457b81fe7b5725 (diff)
Merge commit 'v2.6.26' into bkl-removal
Diffstat (limited to 'net/sctp/outqueue.c')
-rw-r--r--net/sctp/outqueue.c120
1 files changed, 77 insertions, 43 deletions
diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 59edfd25a19..ace6770e904 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -208,6 +208,7 @@ void sctp_outq_init(struct sctp_association *asoc, struct sctp_outq *q)
INIT_LIST_HEAD(&q->sacked);
INIT_LIST_HEAD(&q->abandoned);
+ q->fast_rtx = 0;
q->outstanding_bytes = 0;
q->empty = 1;
q->cork = 0;
@@ -500,6 +501,7 @@ void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
case SCTP_RTXR_FAST_RTX:
SCTP_INC_STATS(SCTP_MIB_FAST_RETRANSMITS);
sctp_transport_lower_cwnd(transport, SCTP_LOWER_CWND_FAST_RTX);
+ q->fast_rtx = 1;
break;
case SCTP_RTXR_PMTUD:
SCTP_INC_STATS(SCTP_MIB_PMTUD_RETRANSMITS);
@@ -518,9 +520,15 @@ void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
* the sender SHOULD try to advance the "Advanced.Peer.Ack.Point" by
* following the procedures outlined in C1 - C5.
*/
- sctp_generate_fwdtsn(q, q->asoc->ctsn_ack_point);
+ if (reason == SCTP_RTXR_T3_RTX)
+ sctp_generate_fwdtsn(q, q->asoc->ctsn_ack_point);
- error = sctp_outq_flush(q, /* rtx_timeout */ 1);
+ /* Flush the queues only on timeout, since fast_rtx is only
+ * triggered during sack processing and the queue
+ * will be flushed at the end.
+ */
+ if (reason != SCTP_RTXR_FAST_RTX)
+ error = sctp_outq_flush(q, /* rtx_timeout */ 1);
if (error)
q->asoc->base.sk->sk_err = -error;
@@ -538,17 +546,23 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
int rtx_timeout, int *start_timer)
{
struct list_head *lqueue;
- struct list_head *lchunk;
struct sctp_transport *transport = pkt->transport;
sctp_xmit_t status;
struct sctp_chunk *chunk, *chunk1;
struct sctp_association *asoc;
+ int fast_rtx;
int error = 0;
+ int timer = 0;
+ int done = 0;
asoc = q->asoc;
lqueue = &q->retransmit;
+ fast_rtx = q->fast_rtx;
- /* RFC 2960 6.3.3 Handle T3-rtx Expiration
+ /* This loop handles time-out retransmissions, fast retransmissions,
+ * and retransmissions due to opening of whindow.
+ *
+ * RFC 2960 6.3.3 Handle T3-rtx Expiration
*
* E3) Determine how many of the earliest (i.e., lowest TSN)
* outstanding DATA chunks for the address for which the
@@ -563,12 +577,12 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
* [Just to be painfully clear, if we are retransmitting
* because a timeout just happened, we should send only ONE
* packet of retransmitted data.]
+ *
+ * For fast retransmissions we also send only ONE packet. However,
+ * if we are just flushing the queue due to open window, we'll
+ * try to send as much as possible.
*/
- lchunk = sctp_list_dequeue(lqueue);
-
- while (lchunk) {
- chunk = list_entry(lchunk, struct sctp_chunk,
- transmitted_list);
+ list_for_each_entry_safe(chunk, chunk1, lqueue, transmitted_list) {
/* Make sure that Gap Acked TSNs are not retransmitted. A
* simple approach is just to move such TSNs out of the
@@ -576,58 +590,60 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
* next chunk.
*/
if (chunk->tsn_gap_acked) {
- list_add_tail(lchunk, &transport->transmitted);
- lchunk = sctp_list_dequeue(lqueue);
+ list_del(&chunk->transmitted_list);
+ list_add_tail(&chunk->transmitted_list,
+ &transport->transmitted);
continue;
}
+ /* If we are doing fast retransmit, ignore non-fast_rtransmit
+ * chunks
+ */
+ if (fast_rtx && !chunk->fast_retransmit)
+ continue;
+
/* Attempt to append this chunk to the packet. */
status = sctp_packet_append_chunk(pkt, chunk);
switch (status) {
case SCTP_XMIT_PMTU_FULL:
/* Send this packet. */
- if ((error = sctp_packet_transmit(pkt)) == 0)
- *start_timer = 1;
+ error = sctp_packet_transmit(pkt);
/* If we are retransmitting, we should only
* send a single packet.
*/
- if (rtx_timeout) {
- list_add(lchunk, lqueue);
- lchunk = NULL;
- }
+ if (rtx_timeout || fast_rtx)
+ done = 1;
- /* Bundle lchunk in the next round. */
+ /* Bundle next chunk in the next round. */
break;
case SCTP_XMIT_RWND_FULL:
/* Send this packet. */
- if ((error = sctp_packet_transmit(pkt)) == 0)
- *start_timer = 1;
+ error = sctp_packet_transmit(pkt);
/* Stop sending DATA as there is no more room
* at the receiver.
*/
- list_add(lchunk, lqueue);
- lchunk = NULL;
+ done = 1;
break;
case SCTP_XMIT_NAGLE_DELAY:
/* Send this packet. */
- if ((error = sctp_packet_transmit(pkt)) == 0)
- *start_timer = 1;
+ error = sctp_packet_transmit(pkt);
/* Stop sending DATA because of nagle delay. */
- list_add(lchunk, lqueue);
- lchunk = NULL;
+ done = 1;
break;
default:
/* The append was successful, so add this chunk to
* the transmitted list.
*/
- list_add_tail(lchunk, &transport->transmitted);
+ list_del(&chunk->transmitted_list);
+ list_add_tail(&chunk->transmitted_list,
+ &transport->transmitted);
/* Mark the chunk as ineligible for fast retransmit
* after it is retransmitted.
@@ -635,27 +651,44 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
if (chunk->fast_retransmit > 0)
chunk->fast_retransmit = -1;
- *start_timer = 1;
- q->empty = 0;
+ /* Force start T3-rtx timer when fast retransmitting
+ * the earliest outstanding TSN
+ */
+ if (!timer && fast_rtx &&
+ ntohl(chunk->subh.data_hdr->tsn) ==
+ asoc->ctsn_ack_point + 1)
+ timer = 2;
- /* Retrieve a new chunk to bundle. */
- lchunk = sctp_list_dequeue(lqueue);
+ q->empty = 0;
break;
}
- /* If we are here due to a retransmit timeout or a fast
- * retransmit and if there are any chunks left in the retransmit
- * queue that could not fit in the PMTU sized packet, they need
- * to be marked as ineligible for a subsequent fast retransmit.
- */
- if (rtx_timeout && !lchunk) {
- list_for_each_entry(chunk1, lqueue, transmitted_list) {
- if (chunk1->fast_retransmit > 0)
- chunk1->fast_retransmit = -1;
- }
+ /* Set the timer if there were no errors */
+ if (!error && !timer)
+ timer = 1;
+
+ if (done)
+ break;
+ }
+
+ /* If we are here due to a retransmit timeout or a fast
+ * retransmit and if there are any chunks left in the retransmit
+ * queue that could not fit in the PMTU sized packet, they need
+ * to be marked as ineligible for a subsequent fast retransmit.
+ */
+ if (rtx_timeout || fast_rtx) {
+ list_for_each_entry(chunk1, lqueue, transmitted_list) {
+ if (chunk1->fast_retransmit > 0)
+ chunk1->fast_retransmit = -1;
}
}
+ *start_timer = timer;
+
+ /* Clear fast retransmit hint */
+ if (fast_rtx)
+ q->fast_rtx = 0;
+
return error;
}
@@ -862,7 +895,8 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
rtx_timeout, &start_timer);
if (start_timer)
- sctp_transport_reset_timers(transport);
+ sctp_transport_reset_timers(transport,
+ start_timer-1);
/* This can happen on COOKIE-ECHO resend. Only
* one chunk can get bundled with a COOKIE-ECHO.
@@ -977,7 +1011,7 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
list_add_tail(&chunk->transmitted_list,
&transport->transmitted);
- sctp_transport_reset_timers(transport);
+ sctp_transport_reset_timers(transport, start_timer-1);
q->empty = 0;