freebsd-dev/sys/netinet6
Gleb Smirnoff 08d9c92027 tcp_input/syncache: acquire only read lock on PCB for SYN,!ACK packets
When packet is a SYN packet, we don't need to modify any existing PCB.
Normally SYN arrives on a listening socket, we either create a syncache
entry or generate syncookie, but we don't modify anything with the
listening socket or associated PCB. Thus create a new PCB lookup
mode - rlock if listening. This removes the primary contention point
under SYN flood - the listening socket PCB.

Sidenote: when SYN arrives on a synchronized connection, we still
don't need write access to PCB to send a challenge ACK or just to
drop. There is only one exclusion - tcptw recycling. However,
existing entanglement of tcp_input + stacks doesn't allow to make
this change small. Consider this patch as first approach to the problem.

Reviewed by:	rrs
Differential revision:	https://reviews.freebsd.org/D29576
2021-04-12 08:25:31 -07:00
..
dest6.c
frag6.c net: Introduce IPV6_DSCP(), IPV6_ECN() and IPV6_TRAFFIC_CLASS() macros 2021-03-04 20:56:48 +01:00
icmp6.c Remove per-packet ifa refcounting from IPv6 fast path. 2021-02-15 22:33:12 +00:00
icmp6.h
in6_cksum.c
in6_fib_algo.c Fix dpdk/ldradix fib lookup algorithm preference calculation. 2021-03-07 22:17:53 +00:00
in6_fib.c Fix unused-function waring when compiling with FIB_ALGO. 2021-01-30 23:25:56 +00:00
in6_fib.h Add modular fib lookup framework. 2020-12-25 11:33:17 +00:00
in6_gif.c net: Introduce IPV6_DSCP(), IPV6_ECN() and IPV6_TRAFFIC_CLASS() macros 2021-03-04 20:56:48 +01:00
in6_ifattach.c Remove per-packet ifa refcounting from IPv6 fast path. 2021-02-15 22:33:12 +00:00
in6_ifattach.h
in6_jail.c
in6_mcast.c
in6_pcb.c tcp_input/syncache: acquire only read lock on PCB for SYN,!ACK packets 2021-04-12 08:25:31 -07:00
in6_pcb.h Filter TCP connections to SO_REUSEPORT_LB listen sockets by NUMA domain 2020-12-19 22:04:46 +00:00
in6_pcbgroup.c
in6_proto.c capsicum: Limit socket operations in capability mode 2021-04-07 14:32:56 -04:00
in6_rmx.c
in6_rss.c
in6_rss.h
in6_src.c Remove per-packet ifa refcounting from IPv6 fast path. 2021-02-15 22:33:12 +00:00
in6_var.h Remove per-packet ifa refcounting from IPv6 fast path. 2021-02-15 22:33:12 +00:00
in6.c capsicum: Limit socket operations in capability mode 2021-04-07 14:32:56 -04:00
in6.h Expose nonstandard IPv6 kernel definitions to standalone builds. 2020-12-04 21:51:47 +00:00
ip6_ecn.h
ip6_fastfwd.c
ip6_forward.c
ip6_gre.c
ip6_id.c
ip6_input.c Flush remaining routes from the routing table during VNET shutdown. 2021-03-10 21:10:14 +00:00
ip6_mroute.c Revert "SO_RERROR indicates that receive buffer overflows should be handled as errors." 2021-02-08 22:32:32 +00:00
ip6_mroute.h
ip6_output.c net: Introduce IPV6_DSCP(), IPV6_ECN() and IPV6_TRAFFIC_CLASS() macros 2021-03-04 20:56:48 +01:00
ip6_var.h
ip6.h
ip6protosw.h
ip_fw_nat64.h
ip_fw_nptv6.h
mld6_var.h
mld6.c
mld6.h
nd6_nbr.c Enforce net epoch in in6_selectsrc(). 2021-02-15 22:33:12 +00:00
nd6_rtr.c Fix crash with rtadv-originated multipath IPv6 routes. 2021-02-24 16:44:10 +00:00
nd6.c base: remove if_wg(4) and associated utilities, manpage 2021-03-17 09:14:48 -05:00
nd6.h
pim6_var.h
pim6.h
raw_ip6.c Enforce net epoch in in6_selectsrc(). 2021-02-15 22:33:12 +00:00
raw_ip6.h
route6.c
scope6_var.h
scope6.c
sctp6_usrreq.c net: Introduce IPV6_DSCP(), IPV6_ECN() and IPV6_TRAFFIC_CLASS() macros 2021-03-04 20:56:48 +01:00
sctp6_var.h
send.c Remove per-packet ifa refcounting from IPv6 fast path. 2021-02-15 22:33:12 +00:00
send.h
tcp6_var.h
udp6_usrreq.c [udp6] fix possible panic due to lack of locking. 2021-02-11 12:00:25 +03:00
udp6_var.h