linux/include/net/netns
Amit Cohen 680aea08e7 net: ipv4: Emit notification when fib hardware flags are changed
After installing a route to the kernel, user space receives an
acknowledgment, which means the route was installed in the kernel,
but not necessarily in hardware.

The asynchronous nature of route installation in hardware can lead to a
routing daemon advertising a route before it was actually installed in
hardware. This can result in packet loss or mis-routed packets until the
route is installed in hardware.

It is also possible for a route already installed in hardware to change
its action and therefore its flags. For example, a host route that is
trapping packets can be "promoted" to perform decapsulation following
the installation of an IPinIP/VXLAN tunnel.

Emit RTM_NEWROUTE notifications whenever RTM_F_OFFLOAD/RTM_F_TRAP flags
are changed. The aim is to provide an indication to user-space
(e.g., routing daemons) about the state of the route in hardware.

Introduce a sysctl that controls this behavior.

Keep the default value at 0 (i.e., do not emit notifications) for several
reasons:
- Multiple RTM_NEWROUTE notification per-route might confuse existing
  routing daemons.
- Convergence reasons in routing daemons.
- The extra notifications will negatively impact the insertion rate.
- Not all users are interested in these notifications.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Acked-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-02 17:45:59 -08:00
..
bpf.h bpf, netns: Keep a list of attached bpf_link's 2020-06-30 10:45:08 -07:00
can.h can: remove obsolete version strings 2020-10-12 10:06:39 +02:00
conntrack.h netfilter: conntrack: limit sysctl setting for boolean options 2019-04-30 14:18:56 +02:00
core.h sock: Hide unused variable when !CONFIG_PROC_FS. 2017-12-19 09:58:14 -05:00
dccp.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
generic.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hash.h netns: provide pure entropy for net_hash_mix() 2019-03-28 17:00:45 -07:00
ieee802154_6lowpan.h net: dynamically allocate fqdir structures 2019-05-26 14:08:05 -07:00
ipv4.h net: ipv4: Emit notification when fib hardware flags are changed 2021-02-02 17:45:59 -08:00
ipv6.h ipv6: keep track of routes using src 2019-11-21 14:45:55 -08:00
mib.h mptcp: add and use MIB counter infrastructure 2020-03-29 22:14:49 -07:00
mpls.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
netfilter.h netfilter: don't allocate space for arp/bridge hooks unless needed 2018-01-08 18:01:11 +01:00
nexthop.h nexthop: Convert to blocking notification chain 2020-09-15 16:31:17 -07:00
nftables.h netfilter: nf_tables: coalesce multiple notifications into one skbuff 2020-09-08 13:02:44 +02:00
packet.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sctp.h sctp: add encap_port for netns sock asoc and transport 2020-10-30 15:24:06 -07:00
unix.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
x_tables.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xdp.h net: xsk: track AF_XDP sockets on a per-netns list 2019-01-25 01:50:03 +01:00
xfrm.h xfrm: policy: store inexact policies in an rhashtable 2018-11-09 11:57:47 +01:00