- 08 Mar, 2024 40 commits
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fuyuanli authored
It is useful to expose skb addr and sock addr to user in tracepoint tcp_probe, so that we can get more information while monitoring receiving of tcp data, by ebpf or other ways. For example, we need to identify a packet by seq and end_seq when calculate transmit latency between layer 2 and layer 4 by ebpf, but which is not available in tcp_probe, so we can only use kprobe hooking tcp_rcv_established to get them. But we can use tcp_probe directly if skb addr and sock addr are available, which is more efficient. Signed-off-by:
fuyuanli <fuyuanli@didiglobal.com> Reviewed-by:
Jason Xing <kerneljasonxing@gmail.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
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Jakub Kicinski authored
softnet_data->time_squeeze is sometimes used as a proxy for host overload or indication of scheduling problems. In practice this statistic is very noisy and has hard to grasp units - e.g. is 10 squeezes a second to be expected, or high? Delaying network (NAPI) processing leads to drops on NIC queues but also RTT bloat, impacting pacing and CA decisions. Stalls are a little hard to detect on the Rx side, because there may simply have not been any packets received in given period of time. Packet timestamps help a little bit, but again we don't know if packets are stale because we're not keeping up or because someone (*cough* cgroups) disabled IRQs for a long time. We can, however, use Tx as a proxy for Rx stalls. Most drivers use combined Rx+Tx NAPIs so if Tx gets starved so will Rx. On the Tx side we know exactly when packets get queued, and completed, so there is no uncertainty. This patch adds stall checks to BQL. Why BQL? Because it's a convenient place to add such checks, already called by most drivers, and it has copious free space in its structures (this patch adds no extra cache references or dirtying to the fast path). The algorithm takes one parameter - max delay AKA stall threshold and increments a counter whenever NAPI got delayed for at least that amount of time. It also records the length of the longest stall. To be precise every time NAPI has not polled for at least stall thrs we check if there were any Tx packets queued between last NAPI run and now - stall_thrs/2. Unlike the classic Tx watchdog this mechanism does not ignore stalls caused by Tx being disabled, or loss of link. I don't think the check is worth the complexity, and stall is a stall, whether due to host overload, flow control, link down... doesn't matter much to the application. We have been running this detector in production at Meta for 2 years, with the threshold of 8ms. It's the lowest value where false positives become rare. There's still a constant stream of reported stalls (especially without the ksoftirqd deferral patches reverted), those who like their stall metrics to be 0 may prefer higher value. Signed-off-by:
Jakub Kicinski <kuba@kernel.org> Signed-off-by:
Breno Leitao <leitao@debian.org> Signed-off-by:
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Colin Ian King authored
The inlined helper function calc_tx_descs is not used and is redundant. Remove it. Cleans up clang scan build warning: drivers/net/ethernet/chelsio/cxgb4/sge.c:814:28: warning: unused function 'calc_tx_descs' [-Wunused-function] Signed-off-by:
Colin Ian King <colin.i.king@gmail.com> Signed-off-by:
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Jakub Kicinski authored
Jakub Kicinski says: ==================== netdev: add per-queue statistics Per queue stats keep coming up, so it's about time someone laid the foundation. This series adds the uAPI, a handful of stats and a sample support for bnxt. It's not very comprehensive in terms of stat types or driver support. The expectation is that the support will grow organically. If we have the basic pieces in place it will be easy for reviewers to request new stats, or use of the API in place of ethtool -S. See patch 3 for sample output. v2: https://lore.kernel.org/all/20240229010221.2408413-1-kuba@kernel.org/ v1: https://lore.kernel.org/all/20240226211015.1244807-1-kuba@kernel.org/ rfc: https://lore.kernel.org/all/20240222223629.158254-1-kuba@kernel.org/ ==================== Link: https://lore.kernel.org/r/20240306195509.1502746-1-kuba@kernel.orgSigned-off-by:
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Jakub Kicinski authored
Support per-queue statistics API in bnxt. $ ethtool -S eth0 NIC statistics: [0]: rx_ucast_packets: 1418 [0]: rx_mcast_packets: 178 [0]: rx_bcast_packets: 0 [0]: rx_discards: 0 [0]: rx_errors: 0 [0]: rx_ucast_bytes: 1141815 [0]: rx_mcast_bytes: 16766 [0]: rx_bcast_bytes: 0 [0]: tx_ucast_packets: 1734 ... $ ./cli.py --spec netlink/specs/netdev.yaml \ --dump qstats-get --json '{"scope": "queue"}' [{'ifindex': 2, 'queue-id': 0, 'queue-type': 'rx', 'rx-alloc-fail': 0, 'rx-bytes': 1164931, 'rx-packets': 1641}, ... {'ifindex': 2, 'queue-id': 0, 'queue-type': 'tx', 'tx-bytes': 631494, 'tx-packets': 1771}, ... Reset the per queue counters: $ ethtool -L eth0 combined 4 Inspect again: $ ./cli.py --spec netlink/specs/netdev.yaml \ --dump qstats-get --json '{"scope": "queue"}' [{'ifindex': 2, 'queue-id': 0, 'queue-type': 'rx', 'rx-alloc-fail': 0, 'rx-bytes': 32397, 'rx-packets': 145}, ... {'ifindex': 2, 'queue-id': 0, 'queue-type': 'tx', 'tx-bytes': 37481, 'tx-packets': 196}, ... $ ethtool -S eth0 | head NIC statistics: [0]: rx_ucast_packets: 174 [0]: rx_mcast_packets: 3 [0]: rx_bcast_packets: 0 [0]: rx_discards: 0 [0]: rx_errors: 0 [0]: rx_ucast_bytes: 37151 [0]: rx_mcast_bytes: 267 [0]: rx_bcast_bytes: 0 [0]: tx_ucast_packets: 267 ... Totals are still correct: $ ./cli.py --spec netlink/specs/netdev.yaml --dump qstats-get [{'ifindex': 2, 'rx-alloc-fail': 0, 'rx-bytes': 281949995, 'rx-packets': 216524, 'tx-bytes': 52694905, 'tx-packets': 75546}] $ ip -s link show dev eth0 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000 link/ether 14:23:f2:61:05:40 brd ff:ff:ff:ff:ff:ff RX: bytes packets errors dropped missed mcast 282519546 218100 0 0 0 516 TX: bytes packets errors dropped carrier collsns 53323054 77674 0 0 0 0 Acked-by:Stanislav Fomichev <sdf@google.com> Reviewed-by:
Amritha Nambiar <amritha.nambiar@intel.com> Reviewed-by:
Michael Chan <michael.chan@broadcom.com> Reviewed-by:
Xuan Zhuo <xuanzhuo@linux.alibaba.com> Link: https://lore.kernel.org/r/20240306195509.1502746-4-kuba@kernel.orgSigned-off-by:
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Jakub Kicinski authored
Rx alloc failures are commonly counted by drivers. Support reporting those via netdev-genl queue stats. Acked-by:
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Jakub Kicinski authored
The ethtool-nl family does a good job exposing various protocol related and IEEE/IETF statistics which used to get dumped under ethtool -S, with creative names. Queue stats don't have a netlink API, yet, and remain a lion's share of ethtool -S output for new drivers. Not only is that bad because the names differ driver to driver but it's also bug-prone. Intuitively drivers try to report only the stats for active queues, but querying ethtool stats involves multiple system calls, and the number of stats is read separately from the stats themselves. Worse still when user space asks for values of the stats, it doesn't inform the kernel how big the buffer is. If number of stats increases in the meantime kernel will overflow user buffer. Add a netlink API for dumping queue stats. Queue information is exposed via the netdev-genl family, so add the stats there. Support per-queue and sum-for-device dumps. Latter will be useful when subsequent patches add more interesting common stats than just bytes and packets. The API does not currently distinguish between HW and SW stats. The expectation is that the source of the stats will either not matter much (good packets) or be obvious (skb alloc errors). Acked-by:
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Jakub Kicinski authored
Eric Dumazet says: ==================== net: group together hot data While our recent structure reorganizations were focused on increasing max throughput, there is still an area where improvements are much needed. In many cases, a cpu handles one packet at a time, instead of a nice batch. Hardware interrupt. -> Software interrupt. -> Network/Protocol stacks. If the cpu was idle or busy in other layers, it has to pull many cache lines. This series adds a new net_hotdata structure, where some critical (and read-mostly) data used in rx and tx path is packed in a small number of cache lines. Synthetic benchmarks will not see much difference, but latency of single packet should improve. net_hodata current size on 64bit is 416 bytes, but might grow in the future. Also move RPS definitions to a new include file. ==================== Link: https://lore.kernel.org/r/20240306160031.874438-1-edumazet@google.comSigned-off-by:
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Eric Dumazet authored
rps_sock_flow_table and rps_cpu_mask are used in fast path. Move them to net_hotdata for better cache locality. Signed-off-by:
Eric Dumazet <edumazet@google.com> Acked-by:
Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by:
David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240306160031.874438-19-edumazet@google.comSigned-off-by:
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Eric Dumazet authored
Move RPS related structures and helpers from include/linux/netdevice.h and include/net/sock.h to a new include file. Signed-off-by:
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Eric Dumazet authored
Use a 32bit hole in "struct net_offload" to store the remaining 32bit secrets used by TCPv6 and UDPv6. Signed-off-by:
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Eric Dumazet authored
"struct inet6_protocol" has a 32bit hole in 32bit arches. Use it to store the 32bit secret used by UDP and TCP, to increase cache locality in rx path. Signed-off-by:
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Eric Dumazet authored
"struct net_protocol" has a 32bit hole in 32bit arches. Use it to store the 32bit secret used by UDP and TCP, to increase cache locality in rx path. Signed-off-by:
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Eric Dumazet authored
These structures are read in rx path, move them to net_hotdata for better cache locality. Signed-off-by:
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Eric Dumazet authored
These structures are read in rx path, move them to net_hotdata for better cache locality. Signed-off-by:
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Eric Dumazet authored
These structures are used in GRO and GSO paths. Move them to net_hodata for better cache locality. v2: udpv6_offload definition depends on CONFIG_INET=y Signed-off-by:
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Eric Dumazet authored
skbuff_cache, skbuff_fclone_cache and skb_small_head_cache are used in rx/tx fast paths. Move them to net_hotdata for better cache locality. Signed-off-by:
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Eric Dumazet authored
dev_rx_weight is read from process_backlog(). Move it to net_hotdata for better cache locality. Signed-off-by:
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Eric Dumazet authored
dev_tx_weight is used in tx fast path. Move it to net_hotdata for better cache locality. Signed-off-by:
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Eric Dumazet authored
These are used in TCP fast paths. Move them into net_hotdata for better cache locality. v2: tcpv6_offload definition depends on CONFIG_INET Signed-off-by:
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Eric Dumazet authored
These structures are used in GRO and GSO paths. v2: ipv6_packet_offload definition depends on CONFIG_INET Signed-off-by:
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Eric Dumazet authored
netdev_max_backlog is used in rx fat path. Move it to net_hodata for better cache locality. Signed-off-by:
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Eric Dumazet authored
ptype_all is used in rx/tx fast paths. Move it to net_hotdata for better cache locality. Signed-off-by:
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Eric Dumazet authored
netdev_tstamp_prequeue is used in rx path. Move it to net_hotdata for better cache locality. Signed-off-by:
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Eric Dumazet authored
netdev_budget and netdev_budget are used in rx path (net_rx_action()) Move them into net_hotdata for better cache locality. Signed-off-by:
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Eric Dumazet authored
Instead of spreading networking critical fields all over the places, add a custom net_hotdata structure so that we can precisely control its layout. In this first patch, move : - gro_normal_batch used in rx (GRO stack) - offload_base used in rx and tx (GRO and TSO stacks) Signed-off-by:
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Jakub Kicinski authored
Matthieu Baerts says: ==================== selftests: mptcp: share code and fix shellcheck warnings This series cleans MPTCP selftests code. Patch 1 stops using 'iptables-legacy' if available, but uses 'iptables', which is likely 'iptables-nft' behind. Patches 2, 4 and 6 move duplicated code to mptcp_lib.sh. Patch 3 is a preparation for patch 4, and patch 5 adds generic actions at the creation and deletion of netns. Patches 7 to 11 disable a few shellcheck warnings, and fix the rest, so it is easy to spot real issues later. MPTCP CI is checking that now. Patch 12 avoids redoing some actions at init time twice, e.g. restarting the pm events tool. v1: https://lore.kernel.org/r/20240305-upstream-net-next-20240304-selftests-mptcp-shared-code-shellcheck-v1-0-66618ea5504e@kernel.org ==================== Link: https://lore.kernel.org/r/20240306-upstream-net-next-20240304-selftests-mptcp-shared-code-shellcheck-v2-0-bc79e6e5e6a0@kernel.orgSigned-off-by:
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Matthieu Baerts (NGI0) authored
'make_connection' is launched twice: once for IPv4, once for IPv6. But then, the "pm_nl_ctl events" was launched a first time, killed, then relaunched after for no particular reason. We can then move this code, and the generation of the temp file to exchange, to the init part, and remove extra conditions that no longer needed. Reviewed-by:
Mat Martineau <martineau@kernel.org> Signed-off-by:
Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://lore.kernel.org/r/20240306-upstream-net-next-20240304-selftests-mptcp-shared-code-shellcheck-v2-12-bc79e6e5e6a0@kernel.orgSigned-off-by:
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Matthieu Baerts (NGI0) authored
shellcheck recently helped to prevent issues. It is then good to fix the other harmless issues in order to spot "real" ones later. Here, two categories of warnings are now ignored: - SC2317: Command appears to be unreachable. The cleanup() function is invoked indirectly via the EXIT trap. - SC2086: Double quote to prevent globbing and word splitting. This is recommended, but the current usage is correct and there is no need to do all these modifications to be compliant with this rule. For the modifications: - SC2034: ksft_skip appears unused. - SC2004: $/${} is unnecessary on arithmetic variables. Now this script is shellcheck (0.9.0) compliant. We can easily spot new issues. Reviewed-by: -
Matthieu Baerts (NGI0) authored
shellcheck recently helped to prevent issues. It is then good to fix the other harmless issues in order to spot "real" ones later. Here, two categories of warnings are now ignored: - SC2317: Command appears to be unreachable. The cleanup() function is invoked indirectly via the EXIT trap. - SC2086: Double quote to prevent globbing and word splitting. This is recommended, but the current usage is correct and there is no need to do all these modifications to be compliant with this rule. For the modifications: - SC2034: ksft_skip appears unused. - SC2154: optstring is referenced but not assigned. - SC2006: Use $(...) notation instead of legacy backticks `...`. Now this script is shellcheck (0.9.0) compliant. We can easily spot new issues. Reviewed-by:
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Matthieu Baerts (NGI0) authored
shellcheck recently helped to prevent issues. It is then good to fix the other harmless issues in order to spot "real" ones later. Here, two categories of warnings are now ignored: - SC2317: Command appears to be unreachable. The cleanup() function is invoked indirectly via the EXIT trap. - SC2086: Double quote to prevent globbing and word splitting. This is recommended, but the current usage is correct and there is no need to do all these modifications to be compliant with this rule. For the modifications: - SC2034: ksft_skip appears unused. - SC2006: Use $(...) notation instead of legacy backticks `...`. - SC2145: Argument mixes string and array. Use * or separate argument. Now this script is shellcheck (0.9.0) compliant. We can easily spot new issues. Reviewed-by:
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Matthieu Baerts (NGI0) authored
shellcheck recently helped to prevent issues. It is then good to fix the other harmless issues in order to spot "real" ones later. Here, two categories of warnings are now ignored: - SC2317: Command appears to be unreachable. The cleanup() function is invoked indirectly via the EXIT trap. - SC2086: Double quote to prevent globbing and word splitting. This is recommended, but the current usage is correct and there is no need to do all these modifications to be compliant with this rule. For the modifications: - SC2034: ksft_skip appears unused. - SC2181: Check exit code directly with e.g. 'if mycmd;', not indirectly with $?. - SC2004: $/${} is unnecessary on arithmetic variables. - SC2155: Declare and assign separately to avoid masking return values. - SC2166: Prefer [ p ] && [ q ] as [ p -a q ] is not well defined. - SC2059: Don't use variables in the printf format string. Use printf '..%s..' "$foo". Now this script is shellcheck (0.9.0) compliant. We can easily spot new issues. Reviewed-by: -
Matthieu Baerts (NGI0) authored
shellcheck recently helped to prevent issues. It is then good to fix the other harmless issues in order to spot "real" ones later. Here, two categories of warnings are now ignored: - SC2317: Command appears to be unreachable. The cleanup() function is invoked indirectly via the EXIT trap. - SC2086: Double quote to prevent globbing and word splitting. This is recommended, but the current usage is correct and there is no need to do all these modifications to be compliant with this rule. For the modifications: - SC2034: ksft_skip appears unused. - SC2046: Quote '$(get_msk_inuse)' to prevent word splitting. - SC2006: Use $(...) notation instead of legacy backticks `...`. Now this script is shellcheck (0.9.0) compliant. We can easily spot new issues. Reviewed-by:
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Geliang Tang authored
To avoid duplicated code in different MPTCP selftests, we can add and use helpers defined in mptcp_lib.sh. This patch unifies "pm_nl_ctl events" related code in userspace_pm.sh and mptcp_join.sh into a helper mptcp_lib_events(). Define it in mptcp_lib.sh and use it in both scripts. Note that mptcp_lib_kill_wait is now call before starting 'events' for mptcp_join.sh as well, but that's fine: each test is started from a new netns, so there will not be any existing pid there, and nothing is done when mptcp_lib_kill_wait is called with 0. Signed-off-by:
Geliang Tang <tanggeliang@kylinos.cn> Reviewed-by:
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Geliang Tang authored
Set more the default sysctl values in mptcp_lib_ns_init(). It is fine to do that everywhere, because they could be overridden latter if needed. mptcp_lib_ns_exit() now also try to remove temp netns files used for the stats even for selftests not using them. That's fine to do that because these files have a unique name. Signed-off-by:
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Geliang Tang authored
Add helpers mptcp_lib_ns_init() and mptcp_lib_ns_exit() in mptcp_lib.sh to initialize and delete the given namespaces. Then every test script can invoke these helpers and use all namespaces. Signed-off-by:
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Geliang Tang authored
This patch adds local variables rndh in do_transfer() functions both in mptcp_connect.sh and simult_flows.sh, setting it with ${ns1:4}, not the global variable rndh. The global one is hidden in the next commit. Signed-off-by: -
Geliang Tang authored
This patch exports check_tools() helper from mptcp_join.sh into mptcp_lib.sh as a public one mptcp_lib_check_tools(). The arguments "ip", "ss", "iptables" and "ip6tables" are passed into this helper to indicate whether to check ip tool, ss tool, iptables and ip6tables tools. This helper can be used in every scripts. Signed-off-by:
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Matthieu Baerts (NGI0) authored
Commit 0c4cd3f8 ("selftests: mptcp: join: use 'iptables-legacy' if available") and commit a5a5990c ("selftests: mptcp: sockopt: use 'iptables-legacy' if available") forced using iptables-legacy if available. This was needed because of some issues that were visible when testing the kselftests on a v5.15.x with iptables-nft as default backend. It looks like these errors are no longer present. As mentioned by Pablo [1], the errors were maybe due to missing kernel config. We can then use iptables-nft if it is the default one, instead of using a legacy tool. We can then check the variables iptables and ip6tables are valid. We can keep the variables to easily change it later or add options. Link: https://lore.kernel.org/netdev/ZbFiixyMFpQnxzCH@calendula/ [1] Suggested-by:
Pablo Neira Ayuso <pablo@netfilter.org> Reviewed-by:
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Jakub Kicinski authored
Merge tag 'rxrpc-iothread-20240305' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs David Howells says: ==================== Here are some changes to AF_RXRPC: (1) Cache the transmission serial number of ACK and DATA packets in the rxrpc_txbuf struct and log this in the retransmit tracepoint. (2) Don't use atomics on rxrpc_txbuf::flags[*] and cache the intended wire header flags there too to avoid duplication. (3) Cache the wire checksum in rxrpc_txbuf to make it easier to create jumbo packets in future (which will require altering the wire header to a jumbo header and restoring it back again for retransmission). (4) Fix the protocol names in the wire ACK trailer struct. (5) Strip all the barriers and atomics out of the call timer tracking[*]. (6) Remove atomic handling from call->tx_transmitted and call->acks_prev_seq[*]. (7) Don't bother resetting the DF flag after UDP packet transmission. To change it, we now call directly into UDP code, so it's quick just to set it every time. (8) Merge together the DF/non-DF branches of the DATA transmission to reduce duplication in the code. (9) Add a kvec array into rxrpc_txbuf and start moving things over to it. This paves the way for using page frags. (10) Split (sub)packet preparation and timestamping out of the DATA transmission function. This helps pave the way for future jumbo packet generation. (11) In rxkad, don't pick values out of the wire header stored in rxrpc_txbuf, buf rather find them elsewhere so we can remove the wire header from there. (12) Move rxrpc_send_ACK() to output.c so that it can be merged with rxrpc_send_ack_packet(). (13) Use rxrpc_txbuf::kvec[0] to access the wire header for the packet rather than directly accessing the copy in rxrpc_txbuf. This will allow that to be removed to a page frag. (14) Switch from keeping the transmission buffers in rxrpc_txbuf allocated in the slab to allocating them using page fragment allocators. There are separate allocators for DATA packets (which persist for a while) and control packets (which are discarded immediately). We can then turn on MSG_SPLICE_PAGES when transmitting DATA and ACK packets. We can also get rid of the RCU cleanup on rxrpc_txbufs, preferring instead to release the page frags as soon as possible. (15) Parse received packets before handling timeouts as the former may reset the latter. (16) Make sure we don't retransmit DATA packets after all the packets have been ACK'd. (17) Differentiate traces for PING ACK transmission. (18) Switch to keeping timeouts as ktime_t rather than a number of jiffies as the latter is too coarse a granularity. Only set the call timer at the end of the call event function from the aggregate of all the timeouts, thereby reducing the number of timer calls made. In future, it might be possible to reduce the number of timers from one per call to one per I/O thread and to use a high-precision timer. (19) Record RTT probes after successful transmission rather than recording it before and then cancelling it after if unsuccessful[*]. This allows a number of calls to get the current time to be removed. (20) Clean up the resend algorithm as there's now no need to walk the transmission buffer under lock[*]. DATA packets can be retransmitted as soon as they're found rather than being queued up and transmitted when the locked is dropped. (21) When initially parsing a received ACK packet, extract some of the fields from the ack info to the skbuff private data. This makes it easier to do path MTU discovery in the future when the call to which a PING RESPONSE ACK refers has been deallocated. [*] Possible with the move of almost all code from softirq context to the I/O thread. Link: https://lore.kernel.org/r/20240301163807.385573-1-dhowells@redhat.com/ # v1 Link: https://lore.kernel.org/r/20240304084322.705539-1-dhowells@redhat.com/ # v2 * tag 'rxrpc-iothread-20240305' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (21 commits) rxrpc: Extract useful fields from a received ACK to skb priv data rxrpc: Clean up the resend algorithm rxrpc: Record probes after transmission and reduce number of time-gets rxrpc: Use ktimes for call timeout tracking and set the timer lazily rxrpc: Differentiate PING ACK transmission traces. rxrpc: Don't permit resending after all Tx packets acked rxrpc: Parse received packets before dealing with timeouts rxrpc: Do zerocopy using MSG_SPLICE_PAGES and page frags rxrpc: Use rxrpc_txbuf::kvec[0] instead of rxrpc_txbuf::wire rxrpc: Move rxrpc_send_ACK() to output.c with rxrpc_send_ack_packet() rxrpc: Don't pick values out of the wire header when setting up security rxrpc: Split up the DATA packet transmission function rxrpc: Add a kvec[] to the rxrpc_txbuf struct rxrpc: Merge together DF/non-DF branches of data Tx function rxrpc: Do lazy DF flag resetting rxrpc: Remove atomic handling on some fields only used in I/O thread rxrpc: Strip barriers and atomics off of timer tracking rxrpc: Fix the names of the fields in the ACK trailer struct rxrpc: Note cksum in txbuf rxrpc: Convert rxrpc_txbuf::flags into a mask and don't use atomics ... ==================== Link: https://lore.kernel.org/r/Signed-off-by:
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