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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /tools/testing/selftests/bpf/progs/bpf_dctcp.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'tools/testing/selftests/bpf/progs/bpf_dctcp.c')
-rw-r--r--tools/testing/selftests/bpf/progs/bpf_dctcp.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/bpf_dctcp.c b/tools/testing/selftests/bpf/progs/bpf_dctcp.c
new file mode 100644
index 000000000..460682759
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bpf_dctcp.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Facebook */
+
+/* WARNING: This implemenation is not necessarily the same
+ * as the tcp_dctcp.c. The purpose is mainly for testing
+ * the kernel BPF logic.
+ */
+
+#include <stddef.h>
+#include <linux/bpf.h>
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/tcp.h>
+#include <errno.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include "bpf_tcp_helpers.h"
+
+char _license[] SEC("license") = "GPL";
+
+volatile const char fallback[TCP_CA_NAME_MAX];
+const char bpf_dctcp[] = "bpf_dctcp";
+const char tcp_cdg[] = "cdg";
+char cc_res[TCP_CA_NAME_MAX];
+int tcp_cdg_res = 0;
+int stg_result = 0;
+int ebusy_cnt = 0;
+
+struct {
+ __uint(type, BPF_MAP_TYPE_SK_STORAGE);
+ __uint(map_flags, BPF_F_NO_PREALLOC);
+ __type(key, int);
+ __type(value, int);
+} sk_stg_map SEC(".maps");
+
+#define DCTCP_MAX_ALPHA 1024U
+
+struct dctcp {
+ __u32 old_delivered;
+ __u32 old_delivered_ce;
+ __u32 prior_rcv_nxt;
+ __u32 dctcp_alpha;
+ __u32 next_seq;
+ __u32 ce_state;
+ __u32 loss_cwnd;
+};
+
+static unsigned int dctcp_shift_g = 4; /* g = 1/2^4 */
+static unsigned int dctcp_alpha_on_init = DCTCP_MAX_ALPHA;
+
+static __always_inline void dctcp_reset(const struct tcp_sock *tp,
+ struct dctcp *ca)
+{
+ ca->next_seq = tp->snd_nxt;
+
+ ca->old_delivered = tp->delivered;
+ ca->old_delivered_ce = tp->delivered_ce;
+}
+
+SEC("struct_ops/dctcp_init")
+void BPF_PROG(dctcp_init, struct sock *sk)
+{
+ const struct tcp_sock *tp = tcp_sk(sk);
+ struct dctcp *ca = inet_csk_ca(sk);
+ int *stg;
+
+ if (!(tp->ecn_flags & TCP_ECN_OK) && fallback[0]) {
+ /* Switch to fallback */
+ if (bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)fallback, sizeof(fallback)) == -EBUSY)
+ ebusy_cnt++;
+
+ /* Switch back to myself and the recurred dctcp_init()
+ * will get -EBUSY for all bpf_setsockopt(TCP_CONGESTION),
+ * except the last "cdg" one.
+ */
+ if (bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)bpf_dctcp, sizeof(bpf_dctcp)) == -EBUSY)
+ ebusy_cnt++;
+
+ /* Switch back to fallback */
+ if (bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)fallback, sizeof(fallback)) == -EBUSY)
+ ebusy_cnt++;
+
+ /* Expecting -ENOTSUPP for tcp_cdg_res */
+ tcp_cdg_res = bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)tcp_cdg, sizeof(tcp_cdg));
+ bpf_getsockopt(sk, SOL_TCP, TCP_CONGESTION,
+ (void *)cc_res, sizeof(cc_res));
+ return;
+ }
+
+ ca->prior_rcv_nxt = tp->rcv_nxt;
+ ca->dctcp_alpha = min(dctcp_alpha_on_init, DCTCP_MAX_ALPHA);
+ ca->loss_cwnd = 0;
+ ca->ce_state = 0;
+
+ stg = bpf_sk_storage_get(&sk_stg_map, (void *)tp, NULL, 0);
+ if (stg) {
+ stg_result = *stg;
+ bpf_sk_storage_delete(&sk_stg_map, (void *)tp);
+ }
+ dctcp_reset(tp, ca);
+}
+
+SEC("struct_ops/dctcp_ssthresh")
+__u32 BPF_PROG(dctcp_ssthresh, struct sock *sk)
+{
+ struct dctcp *ca = inet_csk_ca(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ ca->loss_cwnd = tp->snd_cwnd;
+ return max(tp->snd_cwnd - ((tp->snd_cwnd * ca->dctcp_alpha) >> 11U), 2U);
+}
+
+SEC("struct_ops/dctcp_update_alpha")
+void BPF_PROG(dctcp_update_alpha, struct sock *sk, __u32 flags)
+{
+ const struct tcp_sock *tp = tcp_sk(sk);
+ struct dctcp *ca = inet_csk_ca(sk);
+
+ /* Expired RTT */
+ if (!before(tp->snd_una, ca->next_seq)) {
+ __u32 delivered_ce = tp->delivered_ce - ca->old_delivered_ce;
+ __u32 alpha = ca->dctcp_alpha;
+
+ /* alpha = (1 - g) * alpha + g * F */
+
+ alpha -= min_not_zero(alpha, alpha >> dctcp_shift_g);
+ if (delivered_ce) {
+ __u32 delivered = tp->delivered - ca->old_delivered;
+
+ /* If dctcp_shift_g == 1, a 32bit value would overflow
+ * after 8 M packets.
+ */
+ delivered_ce <<= (10 - dctcp_shift_g);
+ delivered_ce /= max(1U, delivered);
+
+ alpha = min(alpha + delivered_ce, DCTCP_MAX_ALPHA);
+ }
+ ca->dctcp_alpha = alpha;
+ dctcp_reset(tp, ca);
+ }
+}
+
+static __always_inline void dctcp_react_to_loss(struct sock *sk)
+{
+ struct dctcp *ca = inet_csk_ca(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ ca->loss_cwnd = tp->snd_cwnd;
+ tp->snd_ssthresh = max(tp->snd_cwnd >> 1U, 2U);
+}
+
+SEC("struct_ops/dctcp_state")
+void BPF_PROG(dctcp_state, struct sock *sk, __u8 new_state)
+{
+ if (new_state == TCP_CA_Recovery &&
+ new_state != BPF_CORE_READ_BITFIELD(inet_csk(sk), icsk_ca_state))
+ dctcp_react_to_loss(sk);
+ /* We handle RTO in dctcp_cwnd_event to ensure that we perform only
+ * one loss-adjustment per RTT.
+ */
+}
+
+static __always_inline void dctcp_ece_ack_cwr(struct sock *sk, __u32 ce_state)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ if (ce_state == 1)
+ tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
+ else
+ tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
+}
+
+/* Minimal DCTP CE state machine:
+ *
+ * S: 0 <- last pkt was non-CE
+ * 1 <- last pkt was CE
+ */
+static __always_inline
+void dctcp_ece_ack_update(struct sock *sk, enum tcp_ca_event evt,
+ __u32 *prior_rcv_nxt, __u32 *ce_state)
+{
+ __u32 new_ce_state = (evt == CA_EVENT_ECN_IS_CE) ? 1 : 0;
+
+ if (*ce_state != new_ce_state) {
+ /* CE state has changed, force an immediate ACK to
+ * reflect the new CE state. If an ACK was delayed,
+ * send that first to reflect the prior CE state.
+ */
+ if (inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
+ dctcp_ece_ack_cwr(sk, *ce_state);
+ bpf_tcp_send_ack(sk, *prior_rcv_nxt);
+ }
+ inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW;
+ }
+ *prior_rcv_nxt = tcp_sk(sk)->rcv_nxt;
+ *ce_state = new_ce_state;
+ dctcp_ece_ack_cwr(sk, new_ce_state);
+}
+
+SEC("struct_ops/dctcp_cwnd_event")
+void BPF_PROG(dctcp_cwnd_event, struct sock *sk, enum tcp_ca_event ev)
+{
+ struct dctcp *ca = inet_csk_ca(sk);
+
+ switch (ev) {
+ case CA_EVENT_ECN_IS_CE:
+ case CA_EVENT_ECN_NO_CE:
+ dctcp_ece_ack_update(sk, ev, &ca->prior_rcv_nxt, &ca->ce_state);
+ break;
+ case CA_EVENT_LOSS:
+ dctcp_react_to_loss(sk);
+ break;
+ default:
+ /* Don't care for the rest. */
+ break;
+ }
+}
+
+SEC("struct_ops/dctcp_cwnd_undo")
+__u32 BPF_PROG(dctcp_cwnd_undo, struct sock *sk)
+{
+ const struct dctcp *ca = inet_csk_ca(sk);
+
+ return max(tcp_sk(sk)->snd_cwnd, ca->loss_cwnd);
+}
+
+extern void tcp_reno_cong_avoid(struct sock *sk, __u32 ack, __u32 acked) __ksym;
+
+SEC("struct_ops/dctcp_reno_cong_avoid")
+void BPF_PROG(dctcp_cong_avoid, struct sock *sk, __u32 ack, __u32 acked)
+{
+ tcp_reno_cong_avoid(sk, ack, acked);
+}
+
+SEC(".struct_ops")
+struct tcp_congestion_ops dctcp_nouse = {
+ .init = (void *)dctcp_init,
+ .set_state = (void *)dctcp_state,
+ .flags = TCP_CONG_NEEDS_ECN,
+ .name = "bpf_dctcp_nouse",
+};
+
+SEC(".struct_ops")
+struct tcp_congestion_ops dctcp = {
+ .init = (void *)dctcp_init,
+ .in_ack_event = (void *)dctcp_update_alpha,
+ .cwnd_event = (void *)dctcp_cwnd_event,
+ .ssthresh = (void *)dctcp_ssthresh,
+ .cong_avoid = (void *)dctcp_cong_avoid,
+ .undo_cwnd = (void *)dctcp_cwnd_undo,
+ .set_state = (void *)dctcp_state,
+ .flags = TCP_CONG_NEEDS_ECN,
+ .name = "bpf_dctcp",
+};