From cc79dd1ba9c1021c2ac6ae200a65ec38ee8db351 Mon Sep 17 00:00:00 2001 From: Ying Xue Date: Mon, 17 Jun 2013 10:54:37 -0400 Subject: tipc: change socket buffer overflow control to respect sk_rcvbuf As per feedback from the netdev community, we change the buffer overflow protection algorithm in receiving sockets so that it always respects the nominal upper limit set in sk_rcvbuf. Instead of scaling up from a small sk_rcvbuf value, which leads to violation of the configured sk_rcvbuf limit, we now calculate the weighted per-message limit by scaling down from a much bigger value, still in the same field, according to the importance priority of the received message. To allow for administrative tunability of the socket receive buffer size, we create a tipc_rmem sysctl variable to allow the user to configure an even bigger value via sysctl command. It is a size of three (min/default/max) to be consistent with things like tcp_rmem. By default, the value initialized in tipc_rmem[1] is equal to the receive socket size needed by a TIPC_CRITICAL_IMPORTANCE message. This value is also set as the default value of sk_rcvbuf. Originally-by: Jon Maloy Cc: Neil Horman Cc: Jon Maloy [Ying: added sysctl variation to Jon's original patch] Signed-off-by: Ying Xue [PG: don't compile sysctl.c if not config'd; add Documentation] Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller --- net/tipc/sysctl.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) create mode 100644 net/tipc/sysctl.c (limited to 'net/tipc/sysctl.c') diff --git a/net/tipc/sysctl.c b/net/tipc/sysctl.c new file mode 100644 index 000000000000..f3fef93325a8 --- /dev/null +++ b/net/tipc/sysctl.c @@ -0,0 +1,64 @@ +/* + * net/tipc/sysctl.c: sysctl interface to TIPC subsystem + * + * Copyright (c) 2013, Wind River Systems + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the names of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include "core.h" + +#include + +static struct ctl_table_header *tipc_ctl_hdr; + +static struct ctl_table tipc_table[] = { + { + .procname = "tipc_rmem", + .data = &sysctl_tipc_rmem, + .maxlen = sizeof(sysctl_tipc_rmem), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + {} +}; + +int tipc_register_sysctl(void) +{ + tipc_ctl_hdr = register_net_sysctl(&init_net, "net/tipc", tipc_table); + if (tipc_ctl_hdr == NULL) + return -ENOMEM; + return 0; +} + +void tipc_unregister_sysctl(void) +{ + unregister_net_sysctl_table(tipc_ctl_hdr); +} -- cgit v1.2.3