diff options
| author | Xin Long <lucien.xin@gmail.com> | 2021-07-25 13:42:51 -0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-07-25 23:06:02 +0100 |
| commit | eacf078cf4c7aa23e9591738511f142cc39b5186 (patch) | |
| tree | 0004a2401d2477cc7176caef1efa159af62df47f | |
| parent | 058e6e0ed0eace43401c945082dec1d669b5b231 (diff) | |
sctp: send pmtu probe only if packet loss in Search Complete state
This patch is to introduce last_rtx_chunks into sctp_transport to detect
if there's any packet retransmission/loss happened by checking against
asoc's rtx_data_chunks in sctp_transport_pl_send().
If there is, namely, transport->last_rtx_chunks != asoc->rtx_data_chunks,
the pmtu probe will be sent out. Otherwise, increment the pl.raise_count
and return when it's in Search Complete state.
With this patch, if in Search Complete state, which is a long period, it
doesn't need to keep probing the current pmtu unless there's data packet
loss. This will save quite some traffic.
v1->v2:
- add the missing Fixes tag.
Fixes: 0dac127c0557 ("sctp: do black hole detection in search complete state")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/sctp/structs.h | 1 | ||||
| -rw-r--r-- | net/sctp/transport.c | 6 |
2 files changed, 6 insertions, 1 deletions
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index f3d414ed208e..651bba654d77 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -984,6 +984,7 @@ struct sctp_transport { } cacc; struct { + __u32 last_rtx_chunks; __u16 pmtu; __u16 probe_size; __u16 probe_high; diff --git a/net/sctp/transport.c b/net/sctp/transport.c index 23e7bd3e3bd4..a3d3ca6dd63d 100644 --- a/net/sctp/transport.c +++ b/net/sctp/transport.c @@ -263,6 +263,7 @@ bool sctp_transport_pl_send(struct sctp_transport *t) if (t->pl.probe_count < SCTP_MAX_PROBES) goto out; + t->pl.last_rtx_chunks = t->asoc->rtx_data_chunks; t->pl.probe_count = 0; if (t->pl.state == SCTP_PL_BASE) { if (t->pl.probe_size == SCTP_BASE_PLPMTU) { /* BASE_PLPMTU Confirmation Failed */ @@ -298,8 +299,10 @@ bool sctp_transport_pl_send(struct sctp_transport *t) out: if (t->pl.state == SCTP_PL_COMPLETE && t->pl.raise_count < 30 && - !t->pl.probe_count) + !t->pl.probe_count && t->pl.last_rtx_chunks == t->asoc->rtx_data_chunks) { t->pl.raise_count++; + return false; + } pr_debug("%s: PLPMTUD: transport: %p, state: %d, pmtu: %d, size: %d, high: %d\n", __func__, t, t->pl.state, t->pl.pmtu, t->pl.probe_size, t->pl.probe_high); @@ -313,6 +316,7 @@ bool sctp_transport_pl_recv(struct sctp_transport *t) pr_debug("%s: PLPMTUD: transport: %p, state: %d, pmtu: %d, size: %d, high: %d\n", __func__, t, t->pl.state, t->pl.pmtu, t->pl.probe_size, t->pl.probe_high); + t->pl.last_rtx_chunks = t->asoc->rtx_data_chunks; t->pl.pmtu = t->pl.probe_size; t->pl.probe_count = 0; if (t->pl.state == SCTP_PL_BASE) { |