openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Merge branch 'sctp-pmtud-convergence' 

Xin Long says:

====================
sctp: make the PLPMTUD probe more effective and efficient

As David Laight noticed, it currently takes quite some time to find
the optimal pmtu in the Search state, and also lacks the black hole
detection in the Search Complete state. This patchset is to address
them to mke the PLPMTUD probe more effective and efficient.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2021-06-24 12:58:03 -07:00
parent 98ebad48b8 fea1d5b17f
commit 1ed1fe2417
4 changed files with 18 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
Documentation/networking/ip-sysctl.rst
View File

@ -2835,10 +2835,14 @@ encap_port - INTEGER
Default: 0
plpmtud_probe_interval - INTEGER
The time interval (in milliseconds) for sending PLPMTUD probe chunks.
These chunks are sent at the specified interval with a variable size
to probe the mtu of a given path between 2 endpoints. PLPMTUD will
be disabled when 0 is set, and other values for it must be >= 5000.
The time interval (in milliseconds) for the PLPMTUD probe timer,
which is configured to expire after this period to receive an
acknowledgment to a probe packet. This is also the time interval
between the probes for the current pmtu when the probe search
is done.
PLPMTUD will be disabled when 0 is set, and other values for it
must be >= 5000.
Default: 0

3
include/net/sctp/structs.h
View File

@ -987,7 +987,8 @@ struct sctp_transport {
__u16 pmtu;
__u16 probe_size;
__u16 probe_high;
__u8 probe_count;
__u8 probe_count:3;
__u8 raise_count:5;
__u8 state;
} pl; /* plpmtud related */

5
net/sctp/sm_statefuns.c
View File

@ -1275,7 +1275,10 @@ enum sctp_disposition sctp_sf_backbeat_8_3(struct net *net,
return SCTP_DISPOSITION_DISCARD;
sctp_transport_pl_recv(link);
return SCTP_DISPOSITION_CONSUME;
if (link->pl.state == SCTP_PL_COMPLETE)
return SCTP_DISPOSITION_CONSUME;
return sctp_sf_send_probe(net, ep, asoc, type, link, commands);
}
max_interval = link->hbinterval + link->rto;

11
net/sctp/transport.c
View File

@ -213,15 +213,10 @@ void sctp_transport_reset_reconf_timer(struct sctp_transport *transport)
void sctp_transport_reset_probe_timer(struct sctp_transport *transport)
{
int scale = 1;
if (timer_pending(&transport->probe_timer))
return;
if (transport->pl.state == SCTP_PL_COMPLETE &&
transport->pl.probe_count == 1)
scale = 30; /* works as PMTU_RAISE_TIMER */
if (!mod_timer(&transport->probe_timer,
jiffies + transport->probe_interval * scale))
jiffies + transport->probe_interval))
sctp_transport_hold(transport);
}
@ -333,13 +328,15 @@ void sctp_transport_pl_recv(struct sctp_transport *t)
t->pl.probe_size += SCTP_PL_MIN_STEP;
if (t->pl.probe_size >= t->pl.probe_high) {
t->pl.probe_high = 0;
t->pl.raise_count = 0;
t->pl.state = SCTP_PL_COMPLETE; /* Search -> Search Complete */
t->pl.probe_size = t->pl.pmtu;
t->pathmtu = t->pl.pmtu + sctp_transport_pl_hlen(t);
sctp_assoc_sync_pmtu(t->asoc);
}
} else if (t->pl.state == SCTP_PL_COMPLETE) {
} else if (t->pl.state == SCTP_PL_COMPLETE && ++t->pl.raise_count == 30) {
/* Raise probe_size again after 30 * interval in Search Complete */
t->pl.state = SCTP_PL_SEARCH; /* Search Complete -> Search */
t->pl.probe_size += SCTP_PL_MIN_STEP;
}