BMC/Intel-BMC/linux.git/net/ipv6/sysctl_net_ipv6.c, branch dev

ipv6: Flow label state ranges

2015-05-04T01:58:01+00:00

This patch divides the IPv6 flow label space into two ranges: 0-7ffff is reserved for flow label manager, 80000-fffff will be used for creating auto flow labels (per RFC6438). This only affects how labels are set on transmit, it does not affect receive. This range split can be disbaled by systcl. Background: IPv6 flow labels have been an unmitigated disappointment thus far in the lifetime of IPv6. Support in HW devices to use them for ECMP is lacking, and OSes don't turn them on by default. If we had these we could get much better hashing in IPv6 networks without resorting to DPI, possibly eliminating some of the motivations to to define new encaps in UDP just for getting ECMP. Unfortunately, the initial specfications of IPv6 did not clarify how they are to be used. There has always been a vague concept that these can be used for ECMP, flow hashing, etc. and we do now have a good standard how to this in RFC6438. The problem is that flow labels can be either stateful or stateless (as in RFC6438), and we are presented with the possibility that a stateless label may collide with a stateful one. Attempts to split the flow label space were rejected in IETF. When we added support in Linux for RFC6438, we could not turn on flow labels by default due to this conflict. This patch splits the flow label space and should give us a path to enabling auto flow labels by default for all IPv6 packets. This is an API change so we need to consider compatibility with existing deployment. The stateful range is chosen to be the lower values in hopes that most uses would have chosen small numbers. Once we resolve the stateless/stateful issue, we can proceed to look at enabling RFC6438 flow labels by default (starting with scaled testing). Signed-off-by: Tom Herbert Signed-off-by: David S. Miller

ipv6: coding style: comparison for equality with NULL

2015-03-31T17:51:54+00:00

The ipv6 code uses a mixture of coding styles. In some instances check for NULL pointer is done as x == NULL and sometimes as !x. !x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris Signed-off-by: David S. Miller

ipv6: introduce idgen_delay and idgen_retries knobs

2015-03-24T02:12:09+00:00

This is specified by RFC 7217. Cc: Erik Kline Cc: Fernando Gont Cc: Lorenzo Colitti Cc: YOSHIFUJI Hideaki/吉藤英明 Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

ipv6: add sysctl_mld_qrv to configure query robustness variable

2014-09-05T05:26:14+00:00

This patch adds a new sysctl_mld_qrv knob to configure the mldv1/v2 query robustness variable. It specifies how many retransmit of unsolicited mld retransmit should happen. Admins might want to tune this on lossy links. Also reset mld state on interface down/up, so we pick up new sysctl settings during interface up event. IPv6 certification requests this knob to be available. I didn't make this knob netns specific, as it is mostly a setting in a physical environment and should be per host. Cc: Flavio Leitner Signed-off-by: Hannes Frederic Sowa Acked-by: Flavio Leitner Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2014-08-06T01:46:26+00:00

Conflicts: drivers/net/Makefile net/ipv6/sysctl_net_ipv6.c Two ipv6_table_template[] additions overlap, so the index of the ipv6_table[x] assignments needed to be adjusted. In the drivers/net/Makefile case, we've gotten rid of the garbage whereby we had to list every single USB networking driver in the top-level Makefile, there is just one "USB_NETWORKING" that guards everything. Signed-off-by: David S. Miller

ipv6: data of fwmark_reflect sysctl needs to be updated on netns construction

2014-08-02T23:16:54+00:00

Fixes: e110861f86094cd ("net: add a sysctl to reflect the fwmark on replies") Cc: Lorenzo Colitti Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

ipv6: Implement automatic flow label generation on transmit

2014-07-08T04:14:21+00:00

Automatically generate flow labels for IPv6 packets on transmit. The flow label is computed based on skb_get_hash. The flow label will only automatically be set when it is zero otherwise (i.e. flow label manager hasn't set one). This supports the transmit side functionality of RFC 6438. Added an IPv6 sysctl auto_flowlabels to enable/disable this behavior system wide, and added IPV6_AUTOFLOWLABEL socket option to enable this functionality per socket. By default, auto flowlabels are disabled to avoid possible conflicts with flow label manager, however if this feature proves useful we may want to enable it by default. It should also be noted that FreeBSD has already implemented automatic flow labels (including the sysctl and socket option). In FreeBSD, automatic flow labels default to enabled. Performance impact: Running super_netperf with 200 flows for TCP_RR and UDP_RR for IPv6. Note that in UDP case, __skb_get_hash will be called for every packet with explains slight regression. In the TCP case the hash is saved in the socket so there is no regression. Automatic flow labels disabled: TCP_RR: 86.53% CPU utilization 127/195/322 90/95/99% latencies 1.40498e+06 tps UDP_RR: 90.70% CPU utilization 118/168/243 90/95/99% latencies 1.50309e+06 tps Automatic flow labels enabled: TCP_RR: 85.90% CPU utilization 128/199/337 90/95/99% latencies 1.40051e+06 UDP_RR 92.61% CPU utilization 115/164/236 90/95/99% latencies 1.4687e+06 Signed-off-by: Tom Herbert Signed-off-by: David S. Miller

net: add a sysctl to reflect the fwmark on replies

2014-05-13T22:35:08+00:00

Kernel-originated IP packets that have no user socket associated with them (e.g., ICMP errors and echo replies, TCP RSTs, etc.) are emitted with a mark of zero. Add a sysctl to make them have the same mark as the packet they are replying to. This allows an administrator that wishes to do so to use mark-based routing, firewalling, etc. for these replies by marking the original packets inbound. Tested using user-mode linux: - ICMP/ICMPv6 echo replies and errors. - TCP RST packets (IPv4 and IPv6). Signed-off-by: Lorenzo Colitti Signed-off-by: David S. Miller

ipv6: add flowlabel_consistency sysctl

2014-01-20T01:12:31+00:00

With the introduction of IPV6_FL_F_REFLECT, there is no guarantee of flow label unicity. This patch introduces a new sysctl to protect the old behaviour, enable by default. Changelog of V3: * rename ip6_flowlabel_consistency to flowlabel_consistency * use net_info_ratelimited() * checkpatch cleanups Signed-off-by: Florent Fourcot Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

IPv6: move the anycast_src_echo_reply sysctl to netns_sysctl_ipv6

2014-01-15T02:18:22+00:00

This change move anycast_src_echo_reply sysctl with other ipv6 sysctls. Suggested-by: Hannes Frederic Sowa Signed-off-by: Francois-Xavier Le Bail Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller