From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- tools/perf/examples/bpf/5sec.c | 53 +++ tools/perf/examples/bpf/augmented_raw_syscalls.c | 417 +++++++++++++++++++++++ tools/perf/examples/bpf/empty.c | 12 + tools/perf/examples/bpf/hello.c | 27 ++ tools/perf/examples/bpf/sys_enter_openat.c | 33 ++ 5 files changed, 542 insertions(+) create mode 100644 tools/perf/examples/bpf/5sec.c create mode 100644 tools/perf/examples/bpf/augmented_raw_syscalls.c create mode 100644 tools/perf/examples/bpf/empty.c create mode 100644 tools/perf/examples/bpf/hello.c create mode 100644 tools/perf/examples/bpf/sys_enter_openat.c (limited to 'tools/perf/examples/bpf') diff --git a/tools/perf/examples/bpf/5sec.c b/tools/perf/examples/bpf/5sec.c new file mode 100644 index 000000000..3bd7fc176 --- /dev/null +++ b/tools/perf/examples/bpf/5sec.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + Description: + + . Disable strace like syscall tracing (--no-syscalls), or try tracing + just some (-e *sleep). + + . Attach a filter function to a kernel function, returning when it should + be considered, i.e. appear on the output. + + . Run it system wide, so that any sleep of >= 5 seconds and < than 6 + seconds gets caught. + + . Ask for callgraphs using DWARF info, so that userspace can be unwound + + . While this is running, run something like "sleep 5s". + + . If we decide to add tv_nsec as well, then it becomes: + + int probe(hrtimer_nanosleep, rqtp->tv_sec rqtp->tv_nsec)(void *ctx, int err, long sec, long nsec) + + I.e. add where it comes from (rqtp->tv_nsec) and where it will be + accessible in the function body (nsec) + + # perf trace --no-syscalls -e tools/perf/examples/bpf/5sec.c/call-graph=dwarf/ + 0.000 perf_bpf_probe:func:(ffffffff9811b5f0) tv_sec=5 + hrtimer_nanosleep ([kernel.kallsyms]) + __x64_sys_nanosleep ([kernel.kallsyms]) + do_syscall_64 ([kernel.kallsyms]) + entry_SYSCALL_64 ([kernel.kallsyms]) + __GI___nanosleep (/usr/lib64/libc-2.26.so) + rpl_nanosleep (/usr/bin/sleep) + xnanosleep (/usr/bin/sleep) + main (/usr/bin/sleep) + __libc_start_main (/usr/lib64/libc-2.26.so) + _start (/usr/bin/sleep) + ^C# + + Copyright (C) 2018 Red Hat, Inc., Arnaldo Carvalho de Melo +*/ + +#include +#include + +#define NSEC_PER_SEC 1000000000L + +SEC("hrtimer_nanosleep=hrtimer_nanosleep rqtp") +int hrtimer_nanosleep(void *ctx, int err, long long sec) +{ + return sec / NSEC_PER_SEC == 5ULL; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/perf/examples/bpf/augmented_raw_syscalls.c b/tools/perf/examples/bpf/augmented_raw_syscalls.c new file mode 100644 index 000000000..9a03189d3 --- /dev/null +++ b/tools/perf/examples/bpf/augmented_raw_syscalls.c @@ -0,0 +1,417 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Augment the raw_syscalls tracepoints with the contents of the pointer arguments. + * + * Test it with: + * + * perf trace -e tools/perf/examples/bpf/augmented_raw_syscalls.c cat /etc/passwd > /dev/null + * + * This exactly matches what is marshalled into the raw_syscall:sys_enter + * payload expected by the 'perf trace' beautifiers. + * + * For now it just uses the existing tracepoint augmentation code in 'perf + * trace', in the next csets we'll hook up these with the sys_enter/sys_exit + * code that will combine entry/exit in a strace like way. + */ + +#include +#include +#include + +// FIXME: These should come from system headers +typedef char bool; +typedef int pid_t; +typedef long long int __s64; +typedef __s64 time64_t; + +struct timespec64 { + time64_t tv_sec; + long int tv_nsec; +}; + +/* bpf-output associated map */ +struct __augmented_syscalls__ { + __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); + __type(key, int); + __type(value, __u32); + __uint(max_entries, __NR_CPUS__); +} __augmented_syscalls__ SEC(".maps"); + +/* + * What to augment at entry? + * + * Pointer arg payloads (filenames, etc) passed from userspace to the kernel + */ +struct syscalls_sys_enter { + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, 512); +} syscalls_sys_enter SEC(".maps"); + +/* + * What to augment at exit? + * + * Pointer arg payloads returned from the kernel (struct stat, etc) to userspace. + */ +struct syscalls_sys_exit { + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, 512); +} syscalls_sys_exit SEC(".maps"); + +struct syscall_enter_args { + unsigned long long common_tp_fields; + long syscall_nr; + unsigned long args[6]; +}; + +struct syscall_exit_args { + unsigned long long common_tp_fields; + long syscall_nr; + long ret; +}; + +struct augmented_arg { + unsigned int size; + int err; + char value[PATH_MAX]; +}; + +struct pids_filtered { + __uint(type, BPF_MAP_TYPE_HASH); + __type(key, pid_t); + __type(value, bool); + __uint(max_entries, 64); +} pids_filtered SEC(".maps"); + +/* + * Desired design of maximum size and alignment (see RFC2553) + */ +#define SS_MAXSIZE 128 /* Implementation specific max size */ + +typedef unsigned short sa_family_t; + +/* + * FIXME: Should come from system headers + * + * The definition uses anonymous union and struct in order to control the + * default alignment. + */ +struct sockaddr_storage { + union { + struct { + sa_family_t ss_family; /* address family */ + /* Following field(s) are implementation specific */ + char __data[SS_MAXSIZE - sizeof(unsigned short)]; + /* space to achieve desired size, */ + /* _SS_MAXSIZE value minus size of ss_family */ + }; + void *__align; /* implementation specific desired alignment */ + }; +}; + +struct augmented_args_payload { + struct syscall_enter_args args; + union { + struct { + struct augmented_arg arg, arg2; + }; + struct sockaddr_storage saddr; + char __data[sizeof(struct augmented_arg)]; + }; +}; + +// We need more tmp space than the BPF stack can give us +struct augmented_args_tmp { + __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); + __type(key, int); + __type(value, struct augmented_args_payload); + __uint(max_entries, 1); +} augmented_args_tmp SEC(".maps"); + +static inline struct augmented_args_payload *augmented_args_payload(void) +{ + int key = 0; + return bpf_map_lookup_elem(&augmented_args_tmp, &key); +} + +static inline int augmented__output(void *ctx, struct augmented_args_payload *args, int len) +{ + /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */ + return bpf_perf_event_output(ctx, &__augmented_syscalls__, BPF_F_CURRENT_CPU, args, len); +} + +static inline +unsigned int augmented_arg__read_str(struct augmented_arg *augmented_arg, const void *arg, unsigned int arg_len) +{ + unsigned int augmented_len = sizeof(*augmented_arg); + int string_len = bpf_probe_read_str(&augmented_arg->value, arg_len, arg); + + augmented_arg->size = augmented_arg->err = 0; + /* + * probe_read_str may return < 0, e.g. -EFAULT + * So we leave that in the augmented_arg->size that userspace will + */ + if (string_len > 0) { + augmented_len -= sizeof(augmented_arg->value) - string_len; + augmented_len &= sizeof(augmented_arg->value) - 1; + augmented_arg->size = string_len; + } else { + /* + * So that username notice the error while still being able + * to skip this augmented arg record + */ + augmented_arg->err = string_len; + augmented_len = offsetof(struct augmented_arg, value); + } + + return augmented_len; +} + +SEC("!raw_syscalls:unaugmented") +int syscall_unaugmented(struct syscall_enter_args *args) +{ + return 1; +} + +/* + * These will be tail_called from SEC("raw_syscalls:sys_enter"), so will find in + * augmented_args_tmp what was read by that raw_syscalls:sys_enter and go + * on from there, reading the first syscall arg as a string, i.e. open's + * filename. + */ +SEC("!syscalls:sys_enter_connect") +int sys_enter_connect(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args = augmented_args_payload(); + const void *sockaddr_arg = (const void *)args->args[1]; + unsigned int socklen = args->args[2]; + unsigned int len = sizeof(augmented_args->args); + + if (augmented_args == NULL) + return 1; /* Failure: don't filter */ + + if (socklen > sizeof(augmented_args->saddr)) + socklen = sizeof(augmented_args->saddr); + + bpf_probe_read(&augmented_args->saddr, socklen, sockaddr_arg); + + return augmented__output(args, augmented_args, len + socklen); +} + +SEC("!syscalls:sys_enter_sendto") +int sys_enter_sendto(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args = augmented_args_payload(); + const void *sockaddr_arg = (const void *)args->args[4]; + unsigned int socklen = args->args[5]; + unsigned int len = sizeof(augmented_args->args); + + if (augmented_args == NULL) + return 1; /* Failure: don't filter */ + + if (socklen > sizeof(augmented_args->saddr)) + socklen = sizeof(augmented_args->saddr); + + bpf_probe_read(&augmented_args->saddr, socklen, sockaddr_arg); + + return augmented__output(args, augmented_args, len + socklen); +} + +SEC("!syscalls:sys_enter_open") +int sys_enter_open(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args = augmented_args_payload(); + const void *filename_arg = (const void *)args->args[0]; + unsigned int len = sizeof(augmented_args->args); + + if (augmented_args == NULL) + return 1; /* Failure: don't filter */ + + len += augmented_arg__read_str(&augmented_args->arg, filename_arg, sizeof(augmented_args->arg.value)); + + return augmented__output(args, augmented_args, len); +} + +SEC("!syscalls:sys_enter_openat") +int sys_enter_openat(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args = augmented_args_payload(); + const void *filename_arg = (const void *)args->args[1]; + unsigned int len = sizeof(augmented_args->args); + + if (augmented_args == NULL) + return 1; /* Failure: don't filter */ + + len += augmented_arg__read_str(&augmented_args->arg, filename_arg, sizeof(augmented_args->arg.value)); + + return augmented__output(args, augmented_args, len); +} + +SEC("!syscalls:sys_enter_rename") +int sys_enter_rename(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args = augmented_args_payload(); + const void *oldpath_arg = (const void *)args->args[0], + *newpath_arg = (const void *)args->args[1]; + unsigned int len = sizeof(augmented_args->args), oldpath_len; + + if (augmented_args == NULL) + return 1; /* Failure: don't filter */ + + oldpath_len = augmented_arg__read_str(&augmented_args->arg, oldpath_arg, sizeof(augmented_args->arg.value)); + len += oldpath_len + augmented_arg__read_str((void *)(&augmented_args->arg) + oldpath_len, newpath_arg, sizeof(augmented_args->arg.value)); + + return augmented__output(args, augmented_args, len); +} + +SEC("!syscalls:sys_enter_renameat") +int sys_enter_renameat(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args = augmented_args_payload(); + const void *oldpath_arg = (const void *)args->args[1], + *newpath_arg = (const void *)args->args[3]; + unsigned int len = sizeof(augmented_args->args), oldpath_len; + + if (augmented_args == NULL) + return 1; /* Failure: don't filter */ + + oldpath_len = augmented_arg__read_str(&augmented_args->arg, oldpath_arg, sizeof(augmented_args->arg.value)); + len += oldpath_len + augmented_arg__read_str((void *)(&augmented_args->arg) + oldpath_len, newpath_arg, sizeof(augmented_args->arg.value)); + + return augmented__output(args, augmented_args, len); +} + +#define PERF_ATTR_SIZE_VER0 64 /* sizeof first published struct */ + +// we need just the start, get the size to then copy it +struct perf_event_attr_size { + __u32 type; + /* + * Size of the attr structure, for fwd/bwd compat. + */ + __u32 size; +}; + +SEC("!syscalls:sys_enter_perf_event_open") +int sys_enter_perf_event_open(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args = augmented_args_payload(); + const struct perf_event_attr_size *attr = (const struct perf_event_attr_size *)args->args[0], *attr_read; + unsigned int len = sizeof(augmented_args->args); + + if (augmented_args == NULL) + goto failure; + + if (bpf_probe_read(&augmented_args->__data, sizeof(*attr), attr) < 0) + goto failure; + + attr_read = (const struct perf_event_attr_size *)augmented_args->__data; + + __u32 size = attr_read->size; + + if (!size) + size = PERF_ATTR_SIZE_VER0; + + if (size > sizeof(augmented_args->__data)) + goto failure; + + // Now that we read attr->size and tested it against the size limits, read it completely + if (bpf_probe_read(&augmented_args->__data, size, attr) < 0) + goto failure; + + return augmented__output(args, augmented_args, len + size); +failure: + return 1; /* Failure: don't filter */ +} + +SEC("!syscalls:sys_enter_clock_nanosleep") +int sys_enter_clock_nanosleep(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args = augmented_args_payload(); + const void *rqtp_arg = (const void *)args->args[2]; + unsigned int len = sizeof(augmented_args->args); + __u32 size = sizeof(struct timespec64); + + if (augmented_args == NULL) + goto failure; + + if (size > sizeof(augmented_args->__data)) + goto failure; + + bpf_probe_read(&augmented_args->__data, size, rqtp_arg); + + return augmented__output(args, augmented_args, len + size); +failure: + return 1; /* Failure: don't filter */ +} + +static pid_t getpid(void) +{ + return bpf_get_current_pid_tgid(); +} + +static bool pid_filter__has(struct pids_filtered *pids, pid_t pid) +{ + return bpf_map_lookup_elem(pids, &pid) != NULL; +} + +SEC("raw_syscalls:sys_enter") +int sys_enter(struct syscall_enter_args *args) +{ + struct augmented_args_payload *augmented_args; + /* + * We start len, the amount of data that will be in the perf ring + * buffer, if this is not filtered out by one of pid_filter__has(), + * syscall->enabled, etc, with the non-augmented raw syscall payload, + * i.e. sizeof(augmented_args->args). + * + * We'll add to this as we add augmented syscalls right after that + * initial, non-augmented raw_syscalls:sys_enter payload. + */ + unsigned int len = sizeof(augmented_args->args); + + if (pid_filter__has(&pids_filtered, getpid())) + return 0; + + augmented_args = augmented_args_payload(); + if (augmented_args == NULL) + return 1; + + bpf_probe_read(&augmented_args->args, sizeof(augmented_args->args), args); + + /* + * Jump to syscall specific augmenter, even if the default one, + * "!raw_syscalls:unaugmented" that will just return 1 to return the + * unaugmented tracepoint payload. + */ + bpf_tail_call(args, &syscalls_sys_enter, augmented_args->args.syscall_nr); + + // If not found on the PROG_ARRAY syscalls map, then we're filtering it: + return 0; +} + +SEC("raw_syscalls:sys_exit") +int sys_exit(struct syscall_exit_args *args) +{ + struct syscall_exit_args exit_args; + + if (pid_filter__has(&pids_filtered, getpid())) + return 0; + + bpf_probe_read(&exit_args, sizeof(exit_args), args); + /* + * Jump to syscall specific return augmenter, even if the default one, + * "!raw_syscalls:unaugmented" that will just return 1 to return the + * unaugmented tracepoint payload. + */ + bpf_tail_call(args, &syscalls_sys_exit, exit_args.syscall_nr); + /* + * If not found on the PROG_ARRAY syscalls map, then we're filtering it: + */ + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/perf/examples/bpf/empty.c b/tools/perf/examples/bpf/empty.c new file mode 100644 index 000000000..3e296c0c5 --- /dev/null +++ b/tools/perf/examples/bpf/empty.c @@ -0,0 +1,12 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include + +struct syscall_enter_args; + +SEC("raw_syscalls:sys_enter") +int sys_enter(struct syscall_enter_args *args) +{ + return 0; +} +char _license[] SEC("license") = "GPL"; diff --git a/tools/perf/examples/bpf/hello.c b/tools/perf/examples/bpf/hello.c new file mode 100644 index 000000000..e9080b0df --- /dev/null +++ b/tools/perf/examples/bpf/hello.c @@ -0,0 +1,27 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include + +struct __bpf_stdout__ { + __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); + __type(key, int); + __type(value, __u32); + __uint(max_entries, __NR_CPUS__); +} __bpf_stdout__ SEC(".maps"); + +#define puts(from) \ + ({ const int __len = sizeof(from); \ + char __from[sizeof(from)] = from; \ + bpf_perf_event_output(args, &__bpf_stdout__, BPF_F_CURRENT_CPU, \ + &__from, __len & (sizeof(from) - 1)); }) + +struct syscall_enter_args; + +SEC("raw_syscalls:sys_enter") +int sys_enter(struct syscall_enter_args *args) +{ + puts("Hello, world\n"); + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/perf/examples/bpf/sys_enter_openat.c b/tools/perf/examples/bpf/sys_enter_openat.c new file mode 100644 index 000000000..c4481c390 --- /dev/null +++ b/tools/perf/examples/bpf/sys_enter_openat.c @@ -0,0 +1,33 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Hook into 'openat' syscall entry tracepoint + * + * Test it with: + * + * perf trace -e tools/perf/examples/bpf/sys_enter_openat.c cat /etc/passwd > /dev/null + * + * It'll catch some openat syscalls related to the dynamic linked and + * the last one should be the one for '/etc/passwd'. + * + * The syscall_enter_openat_args can be used to get the syscall fields + * and use them for filtering calls, i.e. use in expressions for + * the return value. + */ + +#include + +struct syscall_enter_openat_args { + unsigned long long unused; + long syscall_nr; + long dfd; + char *filename_ptr; + long flags; + long mode; +}; + +int syscall_enter(openat)(struct syscall_enter_openat_args *args) +{ + return 1; +} + +license(GPL); -- cgit v1.2.3