From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerrit Renker Date: Sat, 09 Jun 2007 18:57:56 +0000 Subject: [PATCH 1/6]: Avoid accumulation of large send credit Message-Id: <200706091957.56966@strip-the-willow> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: dccp@vger.kernel.org [CCID 3]: Avoid accumulation of large send credit Backlogs of packets can accumulate in the CCID3 TX module when for instance the application does not send for a longer time or sends slowly. With regard to computing t_nom, this leads to an accumulation of send credits. The present patch avoids large packet bursts that would result under these conditions, by setting the backlog window of tardiness to one t_ipi unit. Signed-off-by: Gerrit Renker --- net/dccp/ccids/ccid3.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c @@ -352,7 +352,9 @@ static int ccid3_hc_tx_send_packet(struc case TFRC_SSTATE_NO_FBACK: case TFRC_SSTATE_FBACK: delay = ktime_delta(hctx->ccid3hctx_t_nom, now); - ccid3_pr_debug("delay=%ld\n", (long)delay); + /* Resynchronise t_nom when sender has been idle or slow */ + if (delay + (s64)hctx->ccid3hctx_t_ipi < 0) + hctx->ccid3hctx_t_nom = now; /* * Scheduling of packet transmissions [RFC 3448, 4.6] * @@ -361,7 +363,7 @@ static int ccid3_hc_tx_send_packet(struc * else * // send the packet in (t_nom - t_now) milliseconds. */ - if (delay - (s64)hctx->ccid3hctx_delta >= 1000) + else if (delay - (s64)hctx->ccid3hctx_delta >= 1000) return (u32)delay / 1000L; ccid3_hc_tx_update_win_count(hctx, now);