[PATCH 3/3] dccp: make upper bound for seq_window consistent on 32/64 bit
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STALE5764d
From: Gerrit Renker <hidden>
Date: 2011-01-07 11:35:46
The 'seq_window' sysctl sets the initial value for the DCCP Sequence Window, which may range from 32..2^46-1 (RFC 4340, 7.5.2). The patch sets the upper bound consistently to 2^32-1 on both 32 and 64 bit systems, which should be sufficient - with a RTT of 1sec and 1-byte packets, a seq_window of 2^32-1 corresponds to a link speed of 34 Gbps. Signed-off-by: Gerrit Renker <redacted> --- Documentation/networking/dccp.txt | 1 + net/dccp/sysctl.c | 4 +++- 2 files changed, 4 insertions(+), 1 deletions(-)
--- a/Documentation/networking/dccp.txt
+++ b/Documentation/networking/dccp.txt@@ -167,6 +167,7 @@ rx_ccid = 2 seq_window = 100 The initial sequence window (sec. 7.5.2) of the sender. This influences the local ackno validity and the remote seqno validity windows (7.5.1). + Values in the range Wmin = 32 (RFC 4340, 7.5.2) up to 2^32-1 can be set. tx_qlen = 5 The size of the transmit buffer in packets. A value of 0 corresponds --- a/net/dccp/sysctl.c +++ b/net/dccp/sysctl.c
@@ -21,7 +21,8 @@ /* Boundary values */ static int zero = 0, u8_max = 0xFF; -static unsigned long seqw_min = 32; +static unsigned long seqw_min = DCCPF_SEQ_WMIN, + seqw_max = 0xFFFFFFFF; /* maximum on 32 bit */ static struct ctl_table dccp_default_table[] = { {
@@ -31,6 +32,7 @@ static struct ctl_table dccp_default_table[] = { .mode = 0644, .proc_handler = proc_doulongvec_minmax, .extra1 = &seqw_min, /* RFC 4340, 7.5.2 */ + .extra2 = &seqw_max, }, { .procname = "rx_ccid",