kernel/linux.git/include/net/inet_frag.h, branch v6.12.80

net: Rename mono_delivery_time to tstamp_type for scalabilty

2024-05-23T21:14:23+00:00

mono_delivery_time was added to check if skb->tstamp has delivery time in mono clock base (i.e. EDT) otherwise skb->tstamp has timestamp in ingress and delivery_time at egress. Renaming the bitfield from mono_delivery_time to tstamp_type is for extensibilty for other timestamps such as userspace timestamp (i.e. SO_TXTIME) set via sock opts. As we are renaming the mono_delivery_time to tstamp_type, it makes sense to start assigning tstamp_type based on enum defined in this commit. Earlier we used bool arg flag to check if the tstamp is mono in function skb_set_delivery_time, Now the signature of the functions accepts tstamp_type to distinguish between mono and real time. Also skb_set_delivery_type_by_clockid is a new function which accepts clockid to determine the tstamp_type. In future tstamp_type:1 can be extended to support userspace timestamp by increasing the bitfield. Signed-off-by: Abhishek Chauhan Reviewed-by: Willem de Bruijn Reviewed-by: Martin KaFai Lau Link: https://lore.kernel.org/r/20240509211834.3235191-2-quic_abchauha@quicinc.com Signed-off-by: Martin KaFai Lau

inet: frags: eliminate kernel-doc warning

2023-07-15T03:39:29+00:00

Modify the anonymous enum kernel-doc content so that it doesn't cause a kernel-doc warning. inet_frag.h:33: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst Fixes: 1ab1934ed80a ("inet: frags: enum the flag definitions and add descriptions") Signed-off-by: Randy Dunlap Cc: Nikolay Aleksandrov Link: https://lore.kernel.org/r/20230714045127.18752-6-rdunlap@infradead.org Signed-off-by: Jakub Kicinski

net: move dropreason.h to dropreason-core.h

2023-04-21T03:20:49+00:00

This will, after the next patch, hold only the core drop reasons and minimal infrastructure. Fix a small kernel-doc issue while at it, to avoid the move triggering a checker. Signed-off-by: Johannes Berg Signed-off-by: Jakub Kicinski

net: dropreason: add SKB_DROP_REASON_FRAG_REASM_TIMEOUT

2022-11-01T03:14:27+00:00

Used to track skbs freed after a timeout happened in a reassmbly unit. Passing a @reason argument to inet_frag_rbtree_purge() allows to use correct consumed status for frags that have been successfully re-assembled. Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski

net: add missing includes and forward declarations under net/

2022-07-22T11:53:22+00:00

This patch adds missing includes to headers under include/net. All these problems are currently masked by the existing users including the missing dependency before the broken header. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

net: ip: Handle delivery_time in ip defrag

2022-03-03T14:38:48+00:00

A latter patch will postpone the delivery_time clearing until the stack knows the skb is being delivered locally. That will allow other kernel forwarding path (e.g. ip[6]_forward) to keep the delivery_time also. An earlier attempt was to do skb_clear_delivery_time() in ip_local_deliver() and ip6_input(). The discussion [0] requested to move it one step later into ip_local_deliver_finish() and ip6_input_finish() so that the delivery_time can be kept for the ip_vs forwarding path also. To do that, this patch also needs to take care of the (rcv) timestamp usecase in ip_is_fragment(). It needs to expect delivery_time in the skb->tstamp, so it needs to save the mono_delivery_time bit in inet_frag_queue such that the delivery_time (if any) can be restored in the final defragmented skb. [Note that it will only happen when the locally generated skb is looping from egress to ingress over a virtual interface (e.g. veth, loopback...), skb->tstamp may have the delivery time before it is known that it will be delivered locally and received by another sk.] [0]: https://lore.kernel.org/netdev/ca728d81-80e8-3767-d5e-d44f6ad96e43@ssi.bg/ Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller

inet: frags: annotate races around fqdir->dead and fqdir->high_thresh

2022-01-13T13:06:05+00:00

Both fields can be read/written without synchronization, add proper accessors and documentation. Fixes: d5dd88794a13 ("inet: fix various use-after-free in defrags units") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

inet: frags: batch fqdir destroy works

2020-12-12T23:08:54+00:00

On a few of our systems, I found frequent 'unshare(CLONE_NEWNET)' calls make the number of active slab objects including 'sock_inode_cache' type rapidly and continuously increase. As a result, memory pressure occurs. In more detail, I made an artificial reproducer that resembles the workload that we found the problem and reproduce the problem faster. It merely repeats 'unshare(CLONE_NEWNET)' 50,000 times in a loop. It takes about 2 minutes. On 40 CPU cores / 70GB DRAM machine, the available memory continuously reduced in a fast speed (about 120MB per second, 15GB in total within the 2 minutes). Note that the issue don't reproduce on every machine. On my 6 CPU cores machine, the problem didn't reproduce. 'cleanup_net()' and 'fqdir_work_fn()' are functions that deallocate the relevant memory objects. They are asynchronously invoked by the work queues and internally use 'rcu_barrier()' to ensure safe destructions. 'cleanup_net()' works in a batched maneer in a single thread worker, while 'fqdir_work_fn()' works for each 'fqdir_exit()' call in the 'system_wq'. Therefore, 'fqdir_work_fn()' called frequently under the workload and made the contention for 'rcu_barrier()' high. In more detail, the global mutex, 'rcu_state.barrier_mutex' became the bottleneck. This commit avoids such contention by doing the 'rcu_barrier()' and subsequent lightweight works in a batched manner, as similar to that of 'cleanup_net()'. The fqdir hashtable destruction, which is done before the 'rcu_barrier()', is still allowed to run in parallel for fast processing, but this commit makes it to use a dedicated work queue instead of the 'system_wq', to make sure that the number of threads is bounded. Signed-off-by: SeongJae Park Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/20201211112405.31158-1-sjpark@amazon.com Signed-off-by: Jakub Kicinski

inet: frags: re-introduce skb coalescing for local delivery

2019-08-08T22:55:10+00:00

Before commit d4289fcc9b16 ("net: IP6 defrag: use rbtrees for IPv6 defrag"), a netperf UDP_STREAM test[0] using big IPv6 datagrams (thus generating many fragments) and running over an IPsec tunnel, reported more than 6Gbps throughput. After that patch, the same test gets only 9Mbps when receiving on a be2net nic (driver can make a big difference here, for example, ixgbe doesn't seem to be affected). By reusing the IPv4 defragmentation code, IPv6 lost fragment coalescing (IPv4 fragment coalescing was dropped by commit 14fe22e33462 ("Revert "ipv4: use skb coalescing in defragmentation"")). Without fragment coalescing, be2net runs out of Rx ring entries and starts to drop frames (ethtool reports rx_drops_no_frags errors). Since the netperf traffic is only composed of UDP fragments, any lost packet prevents reassembly of the full datagram. Therefore, fragments which have no possibility to ever get reassembled pile up in the reassembly queue, until the memory accounting exeeds the threshold. At that point no fragment is accepted anymore, which effectively discards all netperf traffic. When reassembly timeout expires, some stale fragments are removed from the reassembly queue, so a few packets can be received, reassembled and delivered to the netperf receiver. But the nic still drops frames and soon the reassembly queue gets filled again with stale fragments. These long time frames where no datagram can be received explain why the performance drop is so significant. Re-introducing fragment coalescing is enough to get the initial performances again (6.6Gbps with be2net): driver doesn't drop frames anymore (no more rx_drops_no_frags errors) and the reassembly engine works at full speed. This patch is quite conservative and only coalesces skbs for local IPv4 and IPv6 delivery (in order to avoid changing skb geometry when forwarding). Coalescing could be extended in the future if need be, as more scenarios would probably benefit from it. [0]: Test configuration Sender: ip xfrm policy flush ip xfrm state flush ip xfrm state add src fc00:1::1 dst fc00:2::1 proto esp spi 0x1000 aead 'rfc4106(gcm(aes))' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b 96 mode transport sel src fc00:1::1 dst fc00:2::1 ip xfrm policy add src fc00:1::1 dst fc00:2::1 dir in tmpl src fc00:1::1 dst fc00:2::1 proto esp mode transport action allow ip xfrm state add src fc00:2::1 dst fc00:1::1 proto esp spi 0x1001 aead 'rfc4106(gcm(aes))' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b 96 mode transport sel src fc00:2::1 dst fc00:1::1 ip xfrm policy add src fc00:2::1 dst fc00:1::1 dir out tmpl src fc00:2::1 dst fc00:1::1 proto esp mode transport action allow netserver -D -L fc00:2::1 Receiver: ip xfrm policy flush ip xfrm state flush ip xfrm state add src fc00:2::1 dst fc00:1::1 proto esp spi 0x1001 aead 'rfc4106(gcm(aes))' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b 96 mode transport sel src fc00:2::1 dst fc00:1::1 ip xfrm policy add src fc00:2::1 dst fc00:1::1 dir in tmpl src fc00:2::1 dst fc00:1::1 proto esp mode transport action allow ip xfrm state add src fc00:1::1 dst fc00:2::1 proto esp spi 0x1000 aead 'rfc4106(gcm(aes))' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b 96 mode transport sel src fc00:1::1 dst fc00:2::1 ip xfrm policy add src fc00:1::1 dst fc00:2::1 dir out tmpl src fc00:1::1 dst fc00:2::1 proto esp mode transport action allow netperf -H fc00:2::1 -f k -P 0 -L fc00:1::1 -l 60 -t UDP_STREAM -I 99,5 -i 5,5 -T5,5 -6 Signed-off-by: Guillaume Nault Acked-by: Florian Westphal Signed-off-by: David S. Miller

inet: fix compilation warnings in fqdir_pre_exit()

2019-06-23T18:12:12+00:00

The linux-next commit "inet: fix various use-after-free in defrags units" [1] introduced compilation warnings, ./include/net/inet_frag.h:117:1: warning: 'inline' is not at beginning of declaration [-Wold-style-declaration] static void inline fqdir_pre_exit(struct fqdir *fqdir) ^~~~~~ In file included from ./include/net/netns/ipv4.h:10, from ./include/net/net_namespace.h:20, from ./include/linux/netdevice.h:38, from ./include/linux/icmpv6.h:13, from ./include/linux/ipv6.h:86, from ./include/net/ipv6.h:12, from ./include/rdma/ib_verbs.h:51, from ./include/linux/mlx5/device.h:37, from ./include/linux/mlx5/driver.h:51, from drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:37: [1] https://lore.kernel.org/netdev/20190618180900.88939-3-edumazet@google.com/ Signed-off-by: Qian Cai Signed-off-by: David S. Miller