aboutsummaryrefslogtreecommitdiff
path: root/samples/bpf/trace_event_user.c
diff options
context:
space:
mode:
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 /samples/bpf/trace_event_user.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
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 'samples/bpf/trace_event_user.c')
-rw-r--r--samples/bpf/trace_event_user.c352
1 files changed, 352 insertions, 0 deletions
diff --git a/samples/bpf/trace_event_user.c b/samples/bpf/trace_event_user.c
new file mode 100644
index 000000000..9664749bf
--- /dev/null
+++ b/samples/bpf/trace_event_user.c
@@ -0,0 +1,352 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2016 Facebook
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <linux/perf_event.h>
+#include <linux/bpf.h>
+#include <signal.h>
+#include <errno.h>
+#include <sys/resource.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include "perf-sys.h"
+#include "trace_helpers.h"
+
+#define SAMPLE_FREQ 50
+
+static int pid;
+/* counts, stackmap */
+static int map_fd[2];
+struct bpf_program *prog;
+static bool sys_read_seen, sys_write_seen;
+
+static void print_ksym(__u64 addr)
+{
+ struct ksym *sym;
+
+ if (!addr)
+ return;
+ sym = ksym_search(addr);
+ if (!sym) {
+ printf("ksym not found. Is kallsyms loaded?\n");
+ return;
+ }
+
+ printf("%s;", sym->name);
+ if (!strstr(sym->name, "sys_read"))
+ sys_read_seen = true;
+ else if (!strstr(sym->name, "sys_write"))
+ sys_write_seen = true;
+}
+
+static void print_addr(__u64 addr)
+{
+ if (!addr)
+ return;
+ printf("%llx;", addr);
+}
+
+#define TASK_COMM_LEN 16
+
+struct key_t {
+ char comm[TASK_COMM_LEN];
+ __u32 kernstack;
+ __u32 userstack;
+};
+
+static void print_stack(struct key_t *key, __u64 count)
+{
+ __u64 ip[PERF_MAX_STACK_DEPTH] = {};
+ static bool warned;
+ int i;
+
+ printf("%3lld %s;", count, key->comm);
+ if (bpf_map_lookup_elem(map_fd[1], &key->kernstack, ip) != 0) {
+ printf("---;");
+ } else {
+ for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--)
+ print_ksym(ip[i]);
+ }
+ printf("-;");
+ if (bpf_map_lookup_elem(map_fd[1], &key->userstack, ip) != 0) {
+ printf("---;");
+ } else {
+ for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--)
+ print_addr(ip[i]);
+ }
+ if (count < 6)
+ printf("\r");
+ else
+ printf("\n");
+
+ if (key->kernstack == -EEXIST && !warned) {
+ printf("stackmap collisions seen. Consider increasing size\n");
+ warned = true;
+ } else if ((int)key->kernstack < 0 && (int)key->userstack < 0) {
+ printf("err stackid %d %d\n", key->kernstack, key->userstack);
+ }
+}
+
+static void err_exit(int err)
+{
+ kill(pid, SIGKILL);
+ exit(err);
+}
+
+static void print_stacks(void)
+{
+ struct key_t key = {}, next_key;
+ __u64 value;
+ __u32 stackid = 0, next_id;
+ int error = 1, fd = map_fd[0], stack_map = map_fd[1];
+
+ sys_read_seen = sys_write_seen = false;
+ while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
+ bpf_map_lookup_elem(fd, &next_key, &value);
+ print_stack(&next_key, value);
+ bpf_map_delete_elem(fd, &next_key);
+ key = next_key;
+ }
+ printf("\n");
+ if (!sys_read_seen || !sys_write_seen) {
+ printf("BUG kernel stack doesn't contain sys_read() and sys_write()\n");
+ err_exit(error);
+ }
+
+ /* clear stack map */
+ while (bpf_map_get_next_key(stack_map, &stackid, &next_id) == 0) {
+ bpf_map_delete_elem(stack_map, &next_id);
+ stackid = next_id;
+ }
+}
+
+static inline int generate_load(void)
+{
+ if (system("dd if=/dev/zero of=/dev/null count=5000k status=none") < 0) {
+ printf("failed to generate some load with dd: %s\n", strerror(errno));
+ return -1;
+ }
+
+ return 0;
+}
+
+static void test_perf_event_all_cpu(struct perf_event_attr *attr)
+{
+ int nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+ struct bpf_link **links = calloc(nr_cpus, sizeof(struct bpf_link *));
+ int i, pmu_fd, error = 1;
+
+ if (!links) {
+ printf("malloc of links failed\n");
+ goto err;
+ }
+
+ /* system wide perf event, no need to inherit */
+ attr->inherit = 0;
+
+ /* open perf_event on all cpus */
+ for (i = 0; i < nr_cpus; i++) {
+ pmu_fd = sys_perf_event_open(attr, -1, i, -1, 0);
+ if (pmu_fd < 0) {
+ printf("sys_perf_event_open failed\n");
+ goto all_cpu_err;
+ }
+ links[i] = bpf_program__attach_perf_event(prog, pmu_fd);
+ if (libbpf_get_error(links[i])) {
+ printf("bpf_program__attach_perf_event failed\n");
+ links[i] = NULL;
+ close(pmu_fd);
+ goto all_cpu_err;
+ }
+ }
+
+ if (generate_load() < 0)
+ goto all_cpu_err;
+
+ print_stacks();
+ error = 0;
+all_cpu_err:
+ for (i--; i >= 0; i--)
+ bpf_link__destroy(links[i]);
+err:
+ free(links);
+ if (error)
+ err_exit(error);
+}
+
+static void test_perf_event_task(struct perf_event_attr *attr)
+{
+ struct bpf_link *link = NULL;
+ int pmu_fd, error = 1;
+
+ /* per task perf event, enable inherit so the "dd ..." command can be traced properly.
+ * Enabling inherit will cause bpf_perf_prog_read_time helper failure.
+ */
+ attr->inherit = 1;
+
+ /* open task bound event */
+ pmu_fd = sys_perf_event_open(attr, 0, -1, -1, 0);
+ if (pmu_fd < 0) {
+ printf("sys_perf_event_open failed\n");
+ goto err;
+ }
+ link = bpf_program__attach_perf_event(prog, pmu_fd);
+ if (libbpf_get_error(link)) {
+ printf("bpf_program__attach_perf_event failed\n");
+ link = NULL;
+ close(pmu_fd);
+ goto err;
+ }
+
+ if (generate_load() < 0)
+ goto err;
+
+ print_stacks();
+ error = 0;
+err:
+ bpf_link__destroy(link);
+ if (error)
+ err_exit(error);
+}
+
+static void test_bpf_perf_event(void)
+{
+ struct perf_event_attr attr_type_hw = {
+ .sample_freq = SAMPLE_FREQ,
+ .freq = 1,
+ .type = PERF_TYPE_HARDWARE,
+ .config = PERF_COUNT_HW_CPU_CYCLES,
+ };
+ struct perf_event_attr attr_type_sw = {
+ .sample_freq = SAMPLE_FREQ,
+ .freq = 1,
+ .type = PERF_TYPE_SOFTWARE,
+ .config = PERF_COUNT_SW_CPU_CLOCK,
+ };
+ struct perf_event_attr attr_hw_cache_l1d = {
+ .sample_freq = SAMPLE_FREQ,
+ .freq = 1,
+ .type = PERF_TYPE_HW_CACHE,
+ .config =
+ PERF_COUNT_HW_CACHE_L1D |
+ (PERF_COUNT_HW_CACHE_OP_READ << 8) |
+ (PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16),
+ };
+ struct perf_event_attr attr_hw_cache_branch_miss = {
+ .sample_freq = SAMPLE_FREQ,
+ .freq = 1,
+ .type = PERF_TYPE_HW_CACHE,
+ .config =
+ PERF_COUNT_HW_CACHE_BPU |
+ (PERF_COUNT_HW_CACHE_OP_READ << 8) |
+ (PERF_COUNT_HW_CACHE_RESULT_MISS << 16),
+ };
+ struct perf_event_attr attr_type_raw = {
+ .sample_freq = SAMPLE_FREQ,
+ .freq = 1,
+ .type = PERF_TYPE_RAW,
+ /* Intel Instruction Retired */
+ .config = 0xc0,
+ };
+ struct perf_event_attr attr_type_raw_lock_load = {
+ .sample_freq = SAMPLE_FREQ,
+ .freq = 1,
+ .type = PERF_TYPE_RAW,
+ /* Intel MEM_UOPS_RETIRED.LOCK_LOADS */
+ .config = 0x21d0,
+ /* Request to record lock address from PEBS */
+ .sample_type = PERF_SAMPLE_ADDR,
+ /* Record address value requires precise event */
+ .precise_ip = 2,
+ };
+
+ printf("Test HW_CPU_CYCLES\n");
+ test_perf_event_all_cpu(&attr_type_hw);
+ test_perf_event_task(&attr_type_hw);
+
+ printf("Test SW_CPU_CLOCK\n");
+ test_perf_event_all_cpu(&attr_type_sw);
+ test_perf_event_task(&attr_type_sw);
+
+ printf("Test HW_CACHE_L1D\n");
+ test_perf_event_all_cpu(&attr_hw_cache_l1d);
+ test_perf_event_task(&attr_hw_cache_l1d);
+
+ printf("Test HW_CACHE_BPU\n");
+ test_perf_event_all_cpu(&attr_hw_cache_branch_miss);
+ test_perf_event_task(&attr_hw_cache_branch_miss);
+
+ printf("Test Instruction Retired\n");
+ test_perf_event_all_cpu(&attr_type_raw);
+ test_perf_event_task(&attr_type_raw);
+
+ printf("Test Lock Load\n");
+ test_perf_event_all_cpu(&attr_type_raw_lock_load);
+ test_perf_event_task(&attr_type_raw_lock_load);
+
+ printf("*** PASS ***\n");
+}
+
+
+int main(int argc, char **argv)
+{
+ struct bpf_object *obj = NULL;
+ char filename[256];
+ int error = 1;
+
+ snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+ signal(SIGINT, err_exit);
+ signal(SIGTERM, err_exit);
+
+ if (load_kallsyms()) {
+ printf("failed to process /proc/kallsyms\n");
+ goto cleanup;
+ }
+
+ obj = bpf_object__open_file(filename, NULL);
+ if (libbpf_get_error(obj)) {
+ printf("opening BPF object file failed\n");
+ obj = NULL;
+ goto cleanup;
+ }
+
+ prog = bpf_object__find_program_by_name(obj, "bpf_prog1");
+ if (!prog) {
+ printf("finding a prog in obj file failed\n");
+ goto cleanup;
+ }
+
+ /* load BPF program */
+ if (bpf_object__load(obj)) {
+ printf("loading BPF object file failed\n");
+ goto cleanup;
+ }
+
+ map_fd[0] = bpf_object__find_map_fd_by_name(obj, "counts");
+ map_fd[1] = bpf_object__find_map_fd_by_name(obj, "stackmap");
+ if (map_fd[0] < 0 || map_fd[1] < 0) {
+ printf("finding a counts/stackmap map in obj file failed\n");
+ goto cleanup;
+ }
+
+ pid = fork();
+ if (pid == 0) {
+ read_trace_pipe();
+ return 0;
+ } else if (pid == -1) {
+ printf("couldn't spawn process\n");
+ goto cleanup;
+ }
+
+ test_bpf_perf_event();
+ error = 0;
+
+cleanup:
+ bpf_object__close(obj);
+ err_exit(error);
+}