This commit adds a new sysctl option: net.ipv4.tcp_migrate_req. If this option is enabled or eBPF program is attached, we will be able to migrate child sockets from a listener to another in the same reuseport group after close() or shutdown() syscalls. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210612123224.12525-2-kuniyu@amazon.co.jp
A subsequent patch will add a new multipath hash policy where the packet fields used for multipath hash calculation are determined by user space. This patch adds a sysctl that allows user space to set these fields. The packet fields are represented using a bitmask and are common between IPv4 and IPv6 to allow user space to use the same numbering across both protocols. For example, to hash based on standard 5-tuple: # sysctl -w net.ipv4.fib_multipath_hash_fields=0x0037 net.ipv4.fib_multipath_hash_fields = 0x0037 The kernel rejects unknown fields, for example: # sysctl -w net.ipv4.fib_multipath_hash_fields=0x1000 sysctl: setting key "net.ipv4.fib_multipath_hash_fields": Invalid argument More fields can be added in the future, if needed. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
No longer needed, table pointer arg is now passed via netfilter core. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
tcp_comp_sack_nr max value was already 255. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This sysctl is a bool, can use less storage. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Make room for better packing of netns_ipv4 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Reduce footprint of sysctls. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Reduce footprint of sysctls. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
By shuffling around some fields to remove 8 bytes of hole, we can save one cache line. pahole result before/after the patch : /* size: 768, cachelines: 12, members: 139 */ /* sum members: 673, holes: 11, sum holes: 39 */ /* padding: 56 */ /* paddings: 2, sum paddings: 7 */ /* forced alignments: 1 */ -> /* size: 704, cachelines: 11, members: 139 */ /* sum members: 673, holes: 10, sum holes: 31 */ /* paddings: 2, sum paddings: 7 */ /* forced alignments: 1 */ Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
struct inet_timewait_death_row uses two cache lines, because we want tw_count to use a full cache line to avoid false sharing. Rework its definition and placement in netns_ipv4 so that: 1) We add 60 bytes of padding after tw_count to avoid false sharing, knowing that tcp_death_row will have ____cacheline_aligned_in_smp attribute. 2) We do not risk padding before tcp_death_row, because we move it at the beginning of netns_ipv4, even if new fields are added later. 3) We do not waste 48 bytes of padding after it. Note that I have not changed dccp. pahole result for struct netns_ipv4 before/after the patch : /* size: 832, cachelines: 13, members: 139 */ /* sum members: 721, holes: 12, sum holes: 95 */ /* padding: 16 */ /* paddings: 2, sum paddings: 55 */ -> /* size: 768, cachelines: 12, members: 139 */ /* sum members: 673, holes: 11, sum holes: 39 */ /* padding: 56 */ /* paddings: 2, sum paddings: 7 */ /* forced alignments: 1 */ Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>