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2024-05-15Merge tag 'printk-for-6.10' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Use no_printk() instead of "if (0) printk()" constructs to avoid generating printk index for messages disabled at compile time - Remove deprecated strncpy/strcpy from printk.c - Remove redundant CONFIG_BASE_FULL in favor of CONFIG_BASE_SMALL * tag 'printk-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printk: cleanup deprecated uses of strncpy/strcpy printk: Remove redundant CONFIG_BASE_FULL printk: Change type of CONFIG_BASE_SMALL to bool printk: Fix LOG_CPU_MAX_BUF_SHIFT when BASE_SMALL is enabled ceph: Use no_printk() helper dyndbg: Use *no_printk() helpers dev_printk: Add and use dev_no_printk() printk: Let no_printk() use _printk()
2024-05-06printk: Change type of CONFIG_BASE_SMALL to boolYoann Congal1-1/+1
CONFIG_BASE_SMALL is currently a type int but is only used as a boolean. So, change its type to bool and adapt all usages: CONFIG_BASE_SMALL == 0 becomes !IS_ENABLED(CONFIG_BASE_SMALL) and CONFIG_BASE_SMALL != 0 becomes IS_ENABLED(CONFIG_BASE_SMALL). Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Yoann Congal <yoann.congal@smile.fr> Link: https://lore.kernel.org/r/20240505080343.1471198-3-yoann.congal@smile.fr Signed-off-by: Petr Mladek <pmladek@suse.com>
2024-04-14net: change maximum number of UDP segments to 128Yuri Benditovich1-1/+1
The commit fc8b2a619469 ("net: more strict VIRTIO_NET_HDR_GSO_UDP_L4 validation") adds check of potential number of UDP segments vs UDP_MAX_SEGMENTS in linux/virtio_net.h. After this change certification test of USO guest-to-guest transmit on Windows driver for virtio-net device fails, for example with packet size of ~64K and mss of 536 bytes. In general the USO should not be more restrictive than TSO. Indeed, in case of unreasonably small mss a lot of segments can cause queue overflow and packet loss on the destination. Limit of 128 segments is good for any practical purpose, with minimal meaningful mss of 536 the maximal UDP packet will be divided to ~120 segments. The number of segments for UDP packets is validated vs UDP_MAX_SEGMENTS also in udp.c (v4,v6), this does not affect quest-to-guest path but does affect packets sent to host, for example. It is important to mention that UDP_MAX_SEGMENTS is kernel-only define and not available to user mode socket applications. In order to request MSS smaller than MTU the applications just uses setsockopt with SOL_UDP and UDP_SEGMENT and there is no limitations on socket API level. Fixes: fc8b2a619469 ("net: more strict VIRTIO_NET_HDR_GSO_UDP_L4 validation") Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-03-29udp: do not accept non-tunnel GSO skbs landing in a tunnelAntoine Tenart1-0/+28
When rx-udp-gro-forwarding is enabled UDP packets might be GROed when being forwarded. If such packets might land in a tunnel this can cause various issues and udp_gro_receive makes sure this isn't the case by looking for a matching socket. This is performed in udp4/6_gro_lookup_skb but only in the current netns. This is an issue with tunneled packets when the endpoint is in another netns. In such cases the packets will be GROed at the UDP level, which leads to various issues later on. The same thing can happen with rx-gro-list. We saw this with geneve packets being GROed at the UDP level. In such case gso_size is set; later the packet goes through the geneve rx path, the geneve header is pulled, the offset are adjusted and frag_list skbs are not adjusted with regard to geneve. When those skbs hit skb_fragment, it will misbehave. Different outcomes are possible depending on what the GROed skbs look like; from corrupted packets to kernel crashes. One example is a BUG_ON[1] triggered in skb_segment while processing the frag_list. Because gso_size is wrong (geneve header was pulled) skb_segment thinks there is "geneve header size" of data in frag_list, although it's in fact the next packet. The BUG_ON itself has nothing to do with the issue. This is only one of the potential issues. Looking up for a matching socket in udp_gro_receive is fragile: the lookup could be extended to all netns (not speaking about performances) but nothing prevents those packets from being modified in between and we could still not find a matching socket. It's OK to keep the current logic there as it should cover most cases but we also need to make sure we handle tunnel packets being GROed too early. This is done by extending the checks in udp_unexpected_gso: GSO packets lacking the SKB_GSO_UDP_TUNNEL/_CSUM bits and landing in a tunnel must be segmented. [1] kernel BUG at net/core/skbuff.c:4408! RIP: 0010:skb_segment+0xd2a/0xf70 __udp_gso_segment+0xaa/0x560 Fixes: 9fd1ff5d2ac7 ("udp: Support UDP fraglist GRO/GSO.") Fixes: 36707061d6ba ("udp: allow forwarding of plain (non-fraglisted) UDP GRO packets") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-21udp: add local "peek offset enabled" flagPaolo Abeni1-0/+10
We want to re-organize the struct sock layout. The sk_peek_off field location is problematic, as most protocols want it in the RX read area, while UDP wants it on a cacheline different from sk_receive_queue. Create a local (inside udp_sock) copy of the 'peek offset is enabled' flag and place it inside the same cacheline of reader_queue. Check such flag before reading sk_peek_off. This will save potential false sharing and cache misses in the fast-path. Tested under UDP flood with small packets. The struct sock layout update causes a 4% performance drop, and this patch restores completely the original tput. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/67ab679c15fbf49fa05b3ffe05d91c47ab84f147.1708426665.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-09-14udplite: fix various data-racesEric Dumazet1-4/+2
udp->pcflag, udp->pcslen and udp->pcrlen reads/writes are racy. Move udp->pcflag to udp->udp_flags for atomicity, and add READ_ONCE()/WRITE_ONCE() annotations for pcslen and pcrlen. Fixes: ba4e58eca8aa ("[NET]: Supporting UDP-Lite (RFC 3828) in Linux") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-14udplite: remove UDPLITE_BITEric Dumazet1-3/+2
This flag is set but never read, we can remove it. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-14udp: lockless UDP_ENCAP_L2TPINUDP / UDP_GROEric Dumazet1-5/+4
Move udp->encap_enabled to udp->udp_flags. Add udp_test_and_set_bit() helper to allow lockless udp_tunnel_encap_enable() implementation. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-14udp: move udp->accept_udp_{l4|fraglist} to udp->udp_flagsEric Dumazet1-7/+9
These are read locklessly, move them to udp_flags to fix data-races. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-14udp: move udp->gro_enabled to udp->udp_flagsEric Dumazet1-1/+1
syzbot reported that udp->gro_enabled can be read locklessly. Use one atomic bit from udp->udp_flags. Fixes: e20cf8d3f1f7 ("udp: implement GRO for plain UDP sockets.") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-14udp: move udp->no_check6_rx to udp->udp_flagsEric Dumazet1-5/+5
syzbot reported that udp->no_check6_rx can be read locklessly. Use one atomic bit from udp->udp_flags. Fixes: 1c19448c9ba6 ("net: Make enabling of zero UDP6 csums more restrictive") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-14udp: move udp->no_check6_tx to udp->udp_flagsEric Dumazet1-5/+5
syzbot reported that udp->no_check6_tx can be read locklessly. Use one atomic bit from udp->udp_flags Fixes: 1c19448c9ba6 ("net: Make enabling of zero UDP6 csums more restrictive") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-14udp: introduce udp->udp_flagsEric Dumazet1-7/+21
According to syzbot, it is time to use proper atomic flags for various UDP flags. Add udp_flags field, and convert udp->corkflag to first bit in it. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-18udp: preserve const qualifier in udp_sk()Eric Dumazet1-4/+1
We can change udp_sk() to propagate const qualifier of its argument, thanks to container_of_const() This should avoid some potential errors caused by accidental (const -> not_const) promotion. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-16udp: Introduce optional per-netns hash table.Kuniyuki Iwashima1-0/+2
The maximum hash table size is 64K due to the nature of the protocol. [0] It's smaller than TCP, and fewer sockets can cause a performance drop. On an EC2 c5.24xlarge instance (192 GiB memory), after running iperf3 in different netns, creating 32Mi sockets without data transfer in the root netns causes regression for the iperf3's connection. uhash_entries sockets length Gbps 64K 1 1 5.69 1Mi 16 5.27 2Mi 32 4.90 4Mi 64 4.09 8Mi 128 2.96 16Mi 256 2.06 32Mi 512 1.12 The per-netns hash table breaks the lengthy lists into shorter ones. It is useful on a multi-tenant system with thousands of netns. With smaller hash tables, we can look up sockets faster, isolate noisy neighbours, and reduce lock contention. The max size of the per-netns table is 64K as well. This is because the possible hash range by udp_hashfn() always fits in 64K within the same netns and we cannot make full use of the whole buckets larger than 64K. /* 0 < num < 64K -> X < hash < X + 64K */ (num + net_hash_mix(net)) & mask; Also, the min size is 128. We use a bitmap to search for an available port in udp_lib_get_port(). To keep the bitmap on the stack and not fire the CONFIG_FRAME_WARN error at build time, we round up the table size to 128. The sysctl usage is the same with TCP: $ dmesg | cut -d ' ' -f 6- | grep "UDP hash" UDP hash table entries: 65536 (order: 9, 2097152 bytes, vmalloc) # sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = 65536 # can be changed by uhash_entries # sysctl net.ipv4.udp_child_hash_entries net.ipv4.udp_child_hash_entries = 0 # disabled by default # ip netns add test1 # ip netns exec test1 sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = -65536 # share the global table # sysctl -w net.ipv4.udp_child_hash_entries=100 net.ipv4.udp_child_hash_entries = 100 # ip netns add test2 # ip netns exec test2 sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = 128 # own a per-netns table with 2^n buckets We could optimise the hash table lookup/iteration further by removing the netns comparison for the per-netns one in the future. Also, we could optimise the sparse udp_hslot layout by putting it in udp_table. [0]: https://lore.kernel.org/netdev/4ACC2815.7010101@gmail.com/ Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-08net: Change the udp encap_err_rcv to allow use of {ip,ipv6}_icmp_error()David Howells1-1/+2
Change the udp encap_err_rcv signature to match ip_icmp_error() and ipv6_icmp_error() so that those can be used from the called function and export them. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org
2022-10-24udp: track the forward memory release threshold in an hot cachelinePaolo Abeni1-0/+3
When the receiver process and the BH runs on different cores, udp_rmem_release() experience a cache miss while accessing sk_rcvbuf, as the latter shares the same cacheline with sk_forward_alloc, written by the BH. With this patch, UDP tracks the rcvbuf value and its update via custom SOL_SOCKET socket options, and copies the forward memory threshold value used by udp_rmem_release() in a different cacheline, already accessed by the above function and uncontended. Since the UDP socket init operation grown a bit, factor out the common code between v4 and v6 in a shared helper. Overall the above give a 10% peek throughput increase under UDP flood. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-09-01rxrpc: Fix ICMP/ICMP6 error handlingDavid Howells1-0/+1
Because rxrpc pretends to be a tunnel on top of a UDP/UDP6 socket, allowing it to siphon off UDP packets early in the handling of received UDP packets thereby avoiding the packet going through the UDP receive queue, it doesn't get ICMP packets through the UDP ->sk_error_report() callback. In fact, it doesn't appear that there's any usable option for getting hold of ICMP packets. Fix this by adding a new UDP encap hook to distribute error messages for UDP tunnels. If the hook is set, then the tunnel driver will be able to see ICMP packets. The hook provides the offset into the packet of the UDP header of the original packet that caused the notification. An alternative would be to call the ->error_handler() hook - but that requires that the skbuff be cloned (as ip_icmp_error() or ipv6_cmp_error() do, though isn't really necessary or desirable in rxrpc's case is we want to parse them there and then, not queue them). Changes ======= ver #3) - Fixed an uninitialised variable. ver #2) - Fixed some missing CONFIG_AF_RXRPC_IPV6 conditionals. Fixes: 5271953cad31 ("rxrpc: Use the UDP encap_rcv hook") Signed-off-by: David Howells <dhowells@redhat.com>
2022-01-27udp: remove inner_udp_hdr()Jakub Kicinski1-5/+0
Not used since added in v3.8. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-30vxlan: allow L4 GRO passthroughPaolo Abeni1-0/+6
When passing up an UDP GSO packet with L4 aggregation, there is no need to segment it at the vxlan level. We can propagate the packet untouched and let it be segmented later, if needed. Introduce an helper to allow let the UDP socket to accept any L4 aggregation and use it in the vxlan driver. v1 -> v2: - updated to use the newly introduced UDP socket 'accept*' fields Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-30udp: never accept GSO_FRAGLIST packetsPaolo Abeni1-3/+13
Currently the UDP protocol delivers GSO_FRAGLIST packets to the sockets without the expected segmentation. This change addresses the issue introducing and maintaining a couple of new fields to explicitly accept SKB_GSO_UDP_L4 or GSO_FRAGLIST packets. Additionally updates udp_unexpected_gso() accordingly. UDP sockets enabling UDP_GRO stil keep accept_udp_fraglist zeroed. v1 -> v2: - use 2 bits instead of a whole GSO bitmask (Willem) Fixes: 9fd1ff5d2ac7 ("udp: Support UDP fraglist GRO/GSO.") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-5/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-08udp: Handle ICMP errors for tunnels with same destination port on both endpointsStefano Brivio1-0/+1
For both IPv4 and IPv6, if we can't match errors to a socket, try tunnels before ignoring them. Look up a socket with the original source and destination ports as found in the UDP packet inside the ICMP payload, this will work for tunnels that force the same destination port for both endpoints, i.e. VXLAN and GENEVE. Actually, lwtunnels could break this assumption if they are configured by an external control plane to have different destination ports on the endpoints: in this case, we won't be able to trace ICMP messages back to them. For IPv6 redirect messages, call ip6_redirect() directly with the output interface argument set to the interface we received the packet from (as it's the very interface we should build the exception on), otherwise the new nexthop will be rejected. There's no such need for IPv4. Tunnels can now export an encap_err_lookup() operation that indicates a match. Pass the packet to the lookup function, and if the tunnel driver reports a matching association, continue with regular ICMP error handling. v2: - Added newline between network and transport header sets in __udp{4,6}_lib_err_encap() (David Miller) - Removed redundant skb_reset_network_header(skb); in __udp4_lib_err_encap() - Removed redundant reassignment of iph in __udp4_lib_err_encap() (Sabrina Dubroca) - Edited comment to __udp{4,6}_lib_err_encap() to reflect the fact this won't work with lwtunnels configured to use asymmetric ports. By the way, it's VXLAN, not VxLAN (Jiri Benc) Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07udp: cope with UDP GRO packet misdirectionPaolo Abeni1-0/+6
In some scenarios, the GRO engine can assemble an UDP GRO packet that ultimately lands on a non GRO-enabled socket. This patch tries to address the issue explicitly checking for the UDP socket features before enqueuing the packet, and eventually segmenting the unexpected GRO packet, as needed. We must also cope with re-insertion requests: after segmentation the UDP code calls the helper introduced by the previous patches, as needed. Segmentation is performed by a common helper, which takes care of updating socket and protocol stats is case of failure. rfc v3 -> v1 - fix compile issues with rxrpc - when gso_segment returns NULL, treat is as an error - added 'ipv4' argument to udp_rcv_segment() rfc v2 -> rfc v3 - moved udp_rcv_segment() into net/udp.h, account errors to socket and ns, always return NULL or segs list Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07udp: add support for UDP_GRO cmsgPaolo Abeni1-0/+11
When UDP GRO is enabled, the UDP_GRO cmsg will carry the ingress datagram size. User-space can use such info to compute the original packets layout. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07udp: implement GRO for plain UDP sockets.Paolo Abeni1-1/+2
This is the RX counterpart of commit bec1f6f69736 ("udp: generate gso with UDP_SEGMENT"). When UDP_GRO is enabled, such socket is also eligible for GRO in the rx path: UDP segments directed to such socket are assembled into a larger GSO_UDP_L4 packet. The core UDP GRO support is enabled with setsockopt(UDP_GRO). Initial benchmark numbers: Before: udp rx: 1079 MB/s 769065 calls/s After: udp rx: 1466 MB/s 24877 calls/s This change introduces a side effect in respect to UDP tunnels: after a UDP tunnel creation, now the kernel performs a lookup per ingress UDP packet, while before such lookup happened only if the ingress packet carried a valid internal header csum. rfc v2 -> rfc v3: - fixed typos in macro name and comments - really enforce UDP_GRO_CNT_MAX, instead of UDP_GRO_CNT_MAX + 1 - acquire socket lock in UDP_GRO setsockopt rfc v1 -> rfc v2: - use a new option to enable UDP GRO - use static keys to protect the UDP GRO socket lookup Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07udp: implement complete book-keeping for encap_neededPaolo Abeni1-1/+6
The *encap_needed static keys are enabled by UDP tunnels and several UDP encapsulations type, but they are never turned off. This can cause unneeded overall performance degradation for systems where such features are used transiently. This patch introduces complete book-keeping for such keys, decreasing the usage at socket destruction time, if needed, and avoiding that the same socket could increase the key usage multiple times. rfc v3 -> v1: - add socket lock around udp_tunnel_encap_enable() rfc v2 -> rfc v3: - use udp_tunnel_encap_enable() in setsockopt() Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-26net: Convert GRO SKB handling to list_head.David Miller1-2/+2
Manage pending per-NAPI GRO packets via list_head. Return an SKB pointer from the GRO receive handlers. When GRO receive handlers return non-NULL, it means that this SKB needs to be completed at this time and removed from the NAPI queue. Several operations are greatly simplified by this transformation, especially timing out the oldest SKB in the list when gro_count exceeds MAX_GRO_SKBS, and napi_gro_flush() which walks the queue in reverse order. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26udp: generate gso with UDP_SEGMENTWillem de Bruijn1-0/+3
Support generic segmentation offload for udp datagrams. Callers can concatenate and send at once the payload of multiple datagrams with the same destination. To set segment size, the caller sets socket option UDP_SEGMENT to the length of each discrete payload. This value must be smaller than or equal to the relevant MTU. A follow-up patch adds cmsg UDP_SEGMENT to specify segment size on a per send call basis. Total byte length may then exceed MTU. If not an exact multiple of segment size, the last segment will be shorter. The implementation adds a gso_size field to the udp socket, ip(v6) cmsg cookie and inet_cork structure to be able to set the value at setsockopt or cmsg time and to work with both lockless and corked paths. Initial benchmark numbers show UDP GSO about as expensive as TCP GSO. tcp tso 3197 MB/s 54232 msg/s 54232 calls/s 6,457,754,262 cycles tcp gso 1765 MB/s 29939 msg/s 29939 calls/s 11,203,021,806 cycles tcp without tso/gso * 739 MB/s 12548 msg/s 12548 calls/s 11,205,483,630 cycles udp 876 MB/s 14873 msg/s 624666 calls/s 11,205,777,429 cycles udp gso 2139 MB/s 36282 msg/s 36282 calls/s 11,204,374,561 cycles [*] after reverting commit 0a6b2a1dc2a2 ("tcp: switch to GSO being always on") Measured total system cycles ('-a') for one core while pinning both the network receive path and benchmark process to that core: perf stat -a -C 12 -e cycles \ ./udpgso_bench_tx -C 12 -4 -D "$DST" -l 4 Note the reduction in calls/s with GSO. Bytes per syscall drops increases from 1470 to 61818. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-16udp: use a separate rx queue for packet receptionPaolo Abeni1-0/+3
under udp flood the sk_receive_queue spinlock is heavily contended. This patch try to reduce the contention on such lock adding a second receive queue to the udp sockets; recvmsg() looks first in such queue and, only if empty, tries to fetch the data from sk_receive_queue. The latter is spliced into the newly added queue every time the receive path has to acquire the sk_receive_queue lock. The accounting of forward allocated memory is still protected with the sk_receive_queue lock, so udp_rmem_release() needs to acquire both locks when the forward deficit is flushed. On specific scenarios we can end up acquiring and releasing the sk_receive_queue lock multiple times; that will be covered by the next patch Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-01udp: use sk_protocol instead of pcflag to detect udplite socketsPaolo Abeni1-1/+1
In the udp_sock struct, the 'forward_deficit' and 'pcflag' fields share the same cacheline. While the first is dirtied by udp_recvmsg, the latter is read, possibly several times, by the bottom half processing to discriminate between udp and udplite sockets. With this patch, sk->sk_protocol is used to check is the socket is really an udplite one, avoiding some cache misses per packet and improving the performance under udp_flood with small packet up to 10%. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-09udp: add batching to udp_rmem_release()Eric Dumazet1-0/+3
If udp_recvmsg() constantly releases sk_rmem_alloc for every read packet, it gives opportunity for producers to immediately grab spinlocks and desperatly try adding another packet, causing false sharing. We can add a simple heuristic to give the signal by batches of ~25 % of the queue capacity. This patch considerably increases performance under flood by about 50 %, since the thread draining the queue is no longer slowed by false sharing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07udp: Add GRO functions to UDP socketTom Herbert1-0/+8
This patch adds GRO functions (gro_receive and gro_complete) to UDP sockets. udp_gro_receive is changed to perform socket lookup on a packet. If a socket is found the related GRO functions are called. This features obsoletes using UDP offload infrastructure for GRO (udp_offload). This has the advantage of not being limited to provide offload on a per port basis, GRO is now applied to whatever individual UDP sockets are bound to. This also allows the possbility of "application defined GRO"-- that is we can attach something like a BPF program to a UDP socket to perfrom GRO on an application layer protocol. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04udp: no longer use SLAB_DESTROY_BY_RCUEric Dumazet1-4/+4
Tom Herbert would like not touching UDP socket refcnt for encapsulated traffic. For this to happen, we need to use normal RCU rules, with a grace period before freeing a socket. UDP sockets are not short lived in the high usage case, so the added cost of call_rcu() should not be a concern. This actually removes a lot of complexity in UDP stack. Multicast receives no longer need to hold a bucket spinlock. Note that ip early demux still needs to take a reference on the socket. Same remark for functions used by xt_socket and xt_PROXY netfilter modules, but this might be changed later. Performance for a single UDP socket receiving flood traffic from many RX queues/cpus. Simple udp_rx using simple recvfrom() loop : 438 kpps instead of 374 kpps : 17 % increase of the peak rate. v2: Addressed Willem de Bruijn feedback in multicast handling - keep early demux break in __udp4_lib_demux_lookup() Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <tom@herbertland.com> Cc: Willem de Bruijn <willemb@google.com> Tested-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18netns: constify net_hash_mix() and various callersEric Dumazet1-1/+1
const qualifiers ease code review by making clear which objects are not written in a function. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-05ip: Move checksum convert defines to inetTom Herbert1-15/+1
Move convert_csum from udp_sock to inet_sock. This allows the possibility that we can use convert checksum for different types of sockets and also allows convert checksum to be enabled from inet layer (what we'll want to do when enabling IP_CHECKSUM cmsg). Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01udp: Add support for doing checksum unnecessary conversionTom Herbert1-1/+15
Add support for doing CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion in UDP tunneling path. In the normal UDP path, we call skb_checksum_try_convert after locating the UDP socket. The check is that checksum conversion is enabled for the socket (new flag in UDP socket) and that checksum field is non-zero. In the UDP GRO path, we call skb_gro_checksum_try_convert after checksum is validated and checksum field is non-zero. Since this is already in GRO we assume that checksum conversion is always wanted. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-23net: Make enabling of zero UDP6 csums more restrictiveTom Herbert1-1/+23
RFC 6935 permits zero checksums to be used in IPv6 however this is recommended only for certain tunnel protocols, it does not make checksums completely optional like they are in IPv4. This patch restricts the use of IPv6 zero checksums that was previously intoduced. no_check6_tx and no_check6_rx have been added to control the use of checksums in UDP6 RX and TX path. The normal sk_no_check_{rx,tx} settings are not used (this avoids ambiguity when dealing with a dual stack socket). A helper function has been added (udp_set_no_check6) which can be called by tunnel impelmentations to all zero checksums (send on the socket, and accept them as valid). Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-20udp: add encap_destroy callbackTom Parkin1-0/+1
Users of udp encapsulation currently have an encap_rcv callback which they can use to hook into the udp receive path. In situations where a encapsulation user allocates resources associated with a udp encap socket, it may be convenient to be able to also hook the proto .destroy operation. For example, if an encap user holds a reference to the udp socket, the destroy hook might be used to relinquish this reference. This patch adds a socket destroy hook into udp, which is set and enabled in the same way as the existing encap_rcv hook. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: James Chapman <jchapman@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-09net: Add support for hardware-offloaded encapsulationJoseph Gasparakis1-0/+5
This patch adds support in the kernel for offloading in the NIC Tx and Rx checksumming for encapsulated packets (such as VXLAN and IP GRE). For Tx encapsulation offload, the driver will need to set the right bits in netdev->hw_enc_features. The protocol driver will have to set the skb->encapsulation bit and populate the inner headers, so the NIC driver will use those inner headers to calculate the csum in hardware. For Rx encapsulation offload, the driver will need to set again the skb->encapsulation flag and the skb->ip_csum to CHECKSUM_UNNECESSARY. In that case the protocol driver should push the decapsulated packet up to the stack, again with CHECKSUM_UNNECESSARY. In ether case, the protocol driver should set the skb->encapsulation flag back to zero. Finally the protocol driver should have NETIF_F_RXCSUM flag set in its features. Signed-off-by: Joseph Gasparakis <joseph.gasparakis@intel.com> Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-13UAPI: (Scripted) Disintegrate include/linuxDavid Howells1-21/+1
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
2009-11-10udp: bind() optimisationEric Dumazet1-0/+6
UDP bind() can be O(N^2) in some pathological cases. Thanks to secondary hash tables, we can make it O(N) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-08udp: secondary hash on (local port, local address)Eric Dumazet1-0/+1
Extends udp_table to contain a secondary hash table. socket anchor for this second hash is free, because UDP doesnt use skc_bind_node : We define an union to hold both skc_bind_node & a new hlist_nulls_node udp_portaddr_node udp_lib_get_port() inserts sockets into second hash chain (additional cost of one atomic op) udp_lib_unhash() deletes socket from second hash chain (additional cost of one atomic op) Note : No spinlock lockdep annotation is needed, because lock for the secondary hash chain is always get after lock for primary hash chain. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-08udp: split sk_hash into two u16 hashesEric Dumazet1-0/+2
Union sk_hash with two u16 hashes for udp (no extra memory taken) One 16 bits hash on (local port) value (the previous udp 'hash') One 16 bits hash on (local address, local port) values, initialized but not yet used. This second hash is using jenkin hash for better distribution. Because the 'port' is xored later, a partial hash is performed on local address + net_hash_mix(net) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-07udp: dynamically size hash tables at boot timeEric Dumazet1-3/+3
UDP_HTABLE_SIZE was initialy defined to 128, which is a bit small for several setups. 4000 active UDP sockets -> 32 sockets per chain in average. An incoming frame has to lookup all sockets to find best match, so long chains hurt latency. Instead of a fixed size hash table that cant be perfect for every needs, let UDP stack choose its table size at boot time like tcp/ip route, using alloc_large_system_hash() helper Add an optional boot parameter, uhash_entries=x so that an admin can force a size between 256 and 65536 if needed, like thash_entries and rhash_entries. dmesg logs two new lines : [ 0.647039] UDP hash table entries: 512 (order: 0, 4096 bytes) [ 0.647099] UDP Lite hash table entries: 512 (order: 0, 4096 bytes) Maximal size on 64bit arches would be 65536 slots, ie 1 MBytes for non debugging spinlocks. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-16netns: introduce the net_hash_mix "salt" for hashesPavel Emelyanov1-1/+2
There are many possible ways to add this "salt", thus I made this patch to be the last in the series to change it if required. Currently I propose to use the struct net pointer itself as this salt, but since this pointer is most often cache-line aligned, shift this right to eliminate the bits, that are most often zeroed. After this, simply add this mix to prepared hashfn-s. For CONFIG_NET_NS=n case this salt is 0 and no changes in hashfn appear. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-16udp: add struct net argument to udp_hashfnPavel Emelyanov1-1/+1
Every caller already has this one. The new argument is currently unused, but this will be fixed shortly. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-16udp: introduce a udp_hashfn functionPavel Emelyanov1-0/+5
Currently the chain to store a UDP socket is calculated with simple (x & (UDP_HTABLE_SIZE - 1)). But taking net into account would make this calculation a bit more complex, so moving it into a function would help. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-23[NET]: include/linux/udp.h - remove duplicate includeJoe Perches1-11/+7
Remove duplicate #include <linux/types.h> Combine #ifdef __KERNEL__ blocks Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-06[UDP]: Revert udplite and code split.David S. Miller1-10/+0
This reverts commit db1ed684f6c430c4cdad67d058688b8a1b5e607c ("[IPV6] UDP: Rename IPv6 UDP files."), commit 8be8af8fa4405652e6c0797db5465a4be8afb998 ("[IPV4] UDP: Move IPv4-specific bits to other file.") and commit e898d4db2749c6052072e9bc4448e396cbdeb06a ("[UDP]: Allow users to configure UDP-Lite."). First, udplite is of such small cost, and it is a core protocol just like TCP and normal UDP are. We spent enormous amounts of effort to make udplite share as much code with core UDP as possible. All of that work is less valuable if we're just going to slap a config option on udplite support. It is also causing build failures, as reported on linux-next, showing that the changeset was not tested very well. In fact, this is the second build failure resulting from the udplite change. Finally, the config options provided was a bool, instead of a modular option. Meaning the udplite code does not even get build tested by allmodconfig builds, and furthermore the user is not presented with a reasonable modular build option which is particularly needed by distribution vendors. Signed-off-by: David S. Miller <davem@davemloft.net>