path: root/net/packet/internal.h
AgeCommit message (Collapse)Author
2013-04-25packet: account statistics only in tpacket_stats_uDaniel Borkmann
Currently, packet_sock has a struct tpacket_stats stats member for TPACKET_V1 and TPACKET_V2 statistic accounting, and with TPACKET_V3 ``union tpacket_stats_u stats_u'' was introduced, where however only statistics for TPACKET_V3 are held, and when copied to user space, TPACKET_V3 does some hackery and access also tpacket_stats' stats, although everything could have been done within the union itself. Unify accounting within the tpacket_stats_u union so that we can remove 8 bytes from packet_sock that are there unnecessary. Note that even if we switch to TPACKET_V3 and would use non mmap(2)ed option, this still works due to the union with same types + offsets, that are exposed to the user space. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-25packet: reorder a member in packet_ring_bufferDaniel Borkmann
There's a 4 byte hole in packet_ring_buffer structure before prb_bdqc, that can be filled with 'pending' member, thus we can reduce the overall structure size from 224 bytes to 216 bytes. This also has the side-effect, that in struct packet_sock 2*4 byte holes after the embedded packet_ring_buffer members are removed, and overall, packet_sock can be reduced by 1 cacheline: Before: size: 1344, cachelines: 21, members: 24 After: size: 1280, cachelines: 20, members: 24 Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-19packet: packet fanout rollover during socket overloadWillem de Bruijn
Changes: v3->v2: rebase (no other changes) passes selftest v2->v1: read f->num_members only once fix bug: test rollover mode + flag Minimize packet drop in a fanout group. If one socket is full, roll over packets to another from the group. Maintain flow affinity during normal load using an rxhash fanout policy, while dispersing unexpected traffic storms that hit a single cpu, such as spoofed-source DoS flows. Rollover breaks affinity for flows arriving at saturated sockets during those conditions. The patch adds a fanout policy ROLLOVER that rotates between sockets, filling each socket before moving to the next. It also adds a fanout flag ROLLOVER. If passed along with any other fanout policy, the primary policy is applied until the chosen socket is full. Then, rollover selects another socket, to delay packet drop until the entire system is saturated. Probing sockets is not free. Selecting the last used socket, as rollover does, is a greedy approach that maximizes chance of success, at the cost of extreme load imbalance. In practice, with sufficiently long queues to absorb bursts, sockets are drained in parallel and load balance looks uniform in `top`. To avoid contention, scales counters with number of sockets and accesses them lockfree. Values are bounds checked to ensure correctness. Tested using an application with 9 threads pinned to CPUs, one socket per thread and sufficient busywork per packet operation to limits each thread to handling 32 Kpps. When sent 500 Kpps single UDP stream packets, a FANOUT_CPU setup processes 32 Kpps in total without this patch, 270 Kpps with the patch. Tested with read() and with a packet ring (V1). Also, passes psock_fanout.c unit test added to selftests. Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-07packet: tx_ring: allow the user to choose tx data offsetPaul Chavent
The tx data offset of packet mmap tx ring used to be : (TPACKET2_HDRLEN - sizeof(struct sockaddr_ll)) The problem is that, with SOCK_RAW socket, the payload (14 bytes after the beginning of the user data) is misaligned. This patch allows to let the user gives an offset for it's tx data if he desires. Set sock option PACKET_TX_HAS_OFF to 1, then specify in each frame of your tx ring tp_net for SOCK_DGRAM, or tp_mac for SOCK_RAW. Signed-off-by: Paul Chavent <paul.chavent@onera.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-20packet: Report fanout status via diag enginePavel Emelyanov
Reported value is the same reported by the FANOUT getsockoption, but unlike it, the absent fanout setup results in absent nlattr, rather than in nlattr with zero value. This is done so, since zero fanout report may mean both -- no fanout, and fanout with both id and type zero. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-14packet: Introduce net/packet/internal.h headerPavel Emelyanov
The diag module will need to access some private packet_sock data, so move it to a header in advance. This file will be shared between the af_packet.c and the diag.c Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>