From 90f2f5318b3a5b0898fef0fec9b91376c7de7a2c Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Mon, 23 Nov 2009 15:53:57 -0500 Subject: sctp: Update SWS avaoidance receiver side algorithm We currently send window update SACKs every time we free up 1 PMTU worth of data. That a lot more SACKs then necessary. Instead, we'll now send back the actuall window every time we send a sack, and do window-update SACKs when a fraction of the receive buffer has been opened. The fraction is controlled with a sysctl. Signed-off-by: Vlad Yasevich --- net/sctp/associola.c | 5 +++-- net/sctp/protocol.c | 3 +++ net/sctp/sm_sideeffect.c | 3 +-- net/sctp/sysctl.c | 13 +++++++++++++ 4 files changed, 20 insertions(+), 4 deletions(-) (limited to 'net') diff --git a/net/sctp/associola.c b/net/sctp/associola.c index 8e755ebff3b..37e982510be 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -1383,8 +1383,9 @@ static inline int sctp_peer_needs_update(struct sctp_association *asoc) case SCTP_STATE_SHUTDOWN_RECEIVED: case SCTP_STATE_SHUTDOWN_SENT: if ((asoc->rwnd > asoc->a_rwnd) && - ((asoc->rwnd - asoc->a_rwnd) >= - min_t(__u32, (asoc->base.sk->sk_rcvbuf >> 1), asoc->pathmtu))) + ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32, + (asoc->base.sk->sk_rcvbuf >> sctp_rwnd_upd_shift), + asoc->pathmtu))) return 1; break; default: diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 08ef203d36a..a3c8988758b 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -1258,6 +1258,9 @@ SCTP_STATIC __init int sctp_init(void) /* Set SCOPE policy to enabled */ sctp_scope_policy = SCTP_SCOPE_POLICY_ENABLE; + /* Set the default rwnd update threshold */ + sctp_rwnd_upd_shift = SCTP_DEFAULT_RWND_SHIFT; + sctp_sysctl_register(); INIT_LIST_HEAD(&sctp_address_families); diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c index eda4fe783be..8ae67098e09 100644 --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c @@ -217,8 +217,7 @@ static int sctp_gen_sack(struct sctp_association *asoc, int force, sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); } else { - if (asoc->a_rwnd > asoc->rwnd) - asoc->a_rwnd = asoc->rwnd; + asoc->a_rwnd = asoc->rwnd; sack = sctp_make_sack(asoc); if (!sack) goto nomem; diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c index ab7151da120..ae03ded2bf1 100644 --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -52,6 +52,7 @@ static int int_max = INT_MAX; static int sack_timer_min = 1; static int sack_timer_max = 500; static int addr_scope_max = 3; /* check sctp_scope_policy_t in include/net/sctp/constants.h for max entries */ +static int rwnd_scale_max = 16; extern int sysctl_sctp_mem[3]; extern int sysctl_sctp_rmem[3]; @@ -284,6 +285,18 @@ static ctl_table sctp_table[] = { .extra1 = &zero, .extra2 = &addr_scope_max, }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "rwnd_update_shift", + .data = &sctp_rwnd_upd_shift, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_minmax, + .strategy = &sysctl_intvec, + .extra1 = &one, + .extra2 = &rwnd_scale_max, + }, + { .ctl_name = 0 } }; -- cgit v1.2.3-70-g09d2