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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/prog_tests/usdt.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 '')
-rw-r--r--tools/testing/selftests/bpf/prog_tests/usdt.c420
1 files changed, 420 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/usdt.c b/tools/testing/selftests/bpf/prog_tests/usdt.c
new file mode 100644
index 000000000..56ed1eb9b
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/usdt.c
@@ -0,0 +1,420 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
+#include <test_progs.h>
+
+#define _SDT_HAS_SEMAPHORES 1
+#include "../sdt.h"
+
+#include "test_usdt.skel.h"
+#include "test_urandom_usdt.skel.h"
+
+int lets_test_this(int);
+
+static volatile int idx = 2;
+static volatile __u64 bla = 0xFEDCBA9876543210ULL;
+static volatile short nums[] = {-1, -2, -3, -4};
+
+static volatile struct {
+ int x;
+ signed char y;
+} t1 = { 1, -127 };
+
+#define SEC(name) __attribute__((section(name), used))
+
+unsigned short test_usdt0_semaphore SEC(".probes");
+unsigned short test_usdt3_semaphore SEC(".probes");
+unsigned short test_usdt12_semaphore SEC(".probes");
+
+static void __always_inline trigger_func(int x) {
+ long y = 42;
+
+ if (test_usdt0_semaphore)
+ STAP_PROBE(test, usdt0);
+ if (test_usdt3_semaphore)
+ STAP_PROBE3(test, usdt3, x, y, &bla);
+ if (test_usdt12_semaphore) {
+ STAP_PROBE12(test, usdt12,
+ x, x + 1, y, x + y, 5,
+ y / 7, bla, &bla, -9, nums[x],
+ nums[idx], t1.y);
+ }
+}
+
+static void subtest_basic_usdt(void)
+{
+ LIBBPF_OPTS(bpf_usdt_opts, opts);
+ struct test_usdt *skel;
+ struct test_usdt__bss *bss;
+ int err;
+
+ skel = test_usdt__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "skel_open"))
+ return;
+
+ bss = skel->bss;
+ bss->my_pid = getpid();
+
+ err = test_usdt__attach(skel);
+ if (!ASSERT_OK(err, "skel_attach"))
+ goto cleanup;
+
+ /* usdt0 won't be auto-attached */
+ opts.usdt_cookie = 0xcafedeadbeeffeed;
+ skel->links.usdt0 = bpf_program__attach_usdt(skel->progs.usdt0,
+ 0 /*self*/, "/proc/self/exe",
+ "test", "usdt0", &opts);
+ if (!ASSERT_OK_PTR(skel->links.usdt0, "usdt0_link"))
+ goto cleanup;
+
+ trigger_func(1);
+
+ ASSERT_EQ(bss->usdt0_called, 1, "usdt0_called");
+ ASSERT_EQ(bss->usdt3_called, 1, "usdt3_called");
+ ASSERT_EQ(bss->usdt12_called, 1, "usdt12_called");
+
+ ASSERT_EQ(bss->usdt0_cookie, 0xcafedeadbeeffeed, "usdt0_cookie");
+ ASSERT_EQ(bss->usdt0_arg_cnt, 0, "usdt0_arg_cnt");
+ ASSERT_EQ(bss->usdt0_arg_ret, -ENOENT, "usdt0_arg_ret");
+
+ /* auto-attached usdt3 gets default zero cookie value */
+ ASSERT_EQ(bss->usdt3_cookie, 0, "usdt3_cookie");
+ ASSERT_EQ(bss->usdt3_arg_cnt, 3, "usdt3_arg_cnt");
+
+ ASSERT_EQ(bss->usdt3_arg_rets[0], 0, "usdt3_arg1_ret");
+ ASSERT_EQ(bss->usdt3_arg_rets[1], 0, "usdt3_arg2_ret");
+ ASSERT_EQ(bss->usdt3_arg_rets[2], 0, "usdt3_arg3_ret");
+ ASSERT_EQ(bss->usdt3_args[0], 1, "usdt3_arg1");
+ ASSERT_EQ(bss->usdt3_args[1], 42, "usdt3_arg2");
+ ASSERT_EQ(bss->usdt3_args[2], (uintptr_t)&bla, "usdt3_arg3");
+
+ /* auto-attached usdt12 gets default zero cookie value */
+ ASSERT_EQ(bss->usdt12_cookie, 0, "usdt12_cookie");
+ ASSERT_EQ(bss->usdt12_arg_cnt, 12, "usdt12_arg_cnt");
+
+ ASSERT_EQ(bss->usdt12_args[0], 1, "usdt12_arg1");
+ ASSERT_EQ(bss->usdt12_args[1], 1 + 1, "usdt12_arg2");
+ ASSERT_EQ(bss->usdt12_args[2], 42, "usdt12_arg3");
+ ASSERT_EQ(bss->usdt12_args[3], 42 + 1, "usdt12_arg4");
+ ASSERT_EQ(bss->usdt12_args[4], 5, "usdt12_arg5");
+ ASSERT_EQ(bss->usdt12_args[5], 42 / 7, "usdt12_arg6");
+ ASSERT_EQ(bss->usdt12_args[6], bla, "usdt12_arg7");
+ ASSERT_EQ(bss->usdt12_args[7], (uintptr_t)&bla, "usdt12_arg8");
+ ASSERT_EQ(bss->usdt12_args[8], -9, "usdt12_arg9");
+ ASSERT_EQ(bss->usdt12_args[9], nums[1], "usdt12_arg10");
+ ASSERT_EQ(bss->usdt12_args[10], nums[idx], "usdt12_arg11");
+ ASSERT_EQ(bss->usdt12_args[11], t1.y, "usdt12_arg12");
+
+ /* trigger_func() is marked __always_inline, so USDT invocations will be
+ * inlined in two different places, meaning that each USDT will have
+ * at least 2 different places to be attached to. This verifies that
+ * bpf_program__attach_usdt() handles this properly and attaches to
+ * all possible places of USDT invocation.
+ */
+ trigger_func(2);
+
+ ASSERT_EQ(bss->usdt0_called, 2, "usdt0_called");
+ ASSERT_EQ(bss->usdt3_called, 2, "usdt3_called");
+ ASSERT_EQ(bss->usdt12_called, 2, "usdt12_called");
+
+ /* only check values that depend on trigger_func()'s input value */
+ ASSERT_EQ(bss->usdt3_args[0], 2, "usdt3_arg1");
+
+ ASSERT_EQ(bss->usdt12_args[0], 2, "usdt12_arg1");
+ ASSERT_EQ(bss->usdt12_args[1], 2 + 1, "usdt12_arg2");
+ ASSERT_EQ(bss->usdt12_args[3], 42 + 2, "usdt12_arg4");
+ ASSERT_EQ(bss->usdt12_args[9], nums[2], "usdt12_arg10");
+
+ /* detach and re-attach usdt3 */
+ bpf_link__destroy(skel->links.usdt3);
+
+ opts.usdt_cookie = 0xBADC00C51E;
+ skel->links.usdt3 = bpf_program__attach_usdt(skel->progs.usdt3, -1 /* any pid */,
+ "/proc/self/exe", "test", "usdt3", &opts);
+ if (!ASSERT_OK_PTR(skel->links.usdt3, "usdt3_reattach"))
+ goto cleanup;
+
+ trigger_func(3);
+
+ ASSERT_EQ(bss->usdt3_called, 3, "usdt3_called");
+ /* this time usdt3 has custom cookie */
+ ASSERT_EQ(bss->usdt3_cookie, 0xBADC00C51E, "usdt3_cookie");
+ ASSERT_EQ(bss->usdt3_arg_cnt, 3, "usdt3_arg_cnt");
+
+ ASSERT_EQ(bss->usdt3_arg_rets[0], 0, "usdt3_arg1_ret");
+ ASSERT_EQ(bss->usdt3_arg_rets[1], 0, "usdt3_arg2_ret");
+ ASSERT_EQ(bss->usdt3_arg_rets[2], 0, "usdt3_arg3_ret");
+ ASSERT_EQ(bss->usdt3_args[0], 3, "usdt3_arg1");
+ ASSERT_EQ(bss->usdt3_args[1], 42, "usdt3_arg2");
+ ASSERT_EQ(bss->usdt3_args[2], (uintptr_t)&bla, "usdt3_arg3");
+
+cleanup:
+ test_usdt__destroy(skel);
+}
+
+unsigned short test_usdt_100_semaphore SEC(".probes");
+unsigned short test_usdt_300_semaphore SEC(".probes");
+unsigned short test_usdt_400_semaphore SEC(".probes");
+
+#define R10(F, X) F(X+0); F(X+1);F(X+2); F(X+3); F(X+4); \
+ F(X+5); F(X+6); F(X+7); F(X+8); F(X+9);
+#define R100(F, X) R10(F,X+ 0);R10(F,X+10);R10(F,X+20);R10(F,X+30);R10(F,X+40); \
+ R10(F,X+50);R10(F,X+60);R10(F,X+70);R10(F,X+80);R10(F,X+90);
+
+/* carefully control that we get exactly 100 inlines by preventing inlining */
+static void __always_inline f100(int x)
+{
+ STAP_PROBE1(test, usdt_100, x);
+}
+
+__weak void trigger_100_usdts(void)
+{
+ R100(f100, 0);
+}
+
+/* we shouldn't be able to attach to test:usdt2_300 USDT as we don't have as
+ * many slots for specs. It's important that each STAP_PROBE2() invocation
+ * (after untolling) gets different arg spec due to compiler inlining i as
+ * a constant
+ */
+static void __always_inline f300(int x)
+{
+ STAP_PROBE1(test, usdt_300, x);
+}
+
+__weak void trigger_300_usdts(void)
+{
+ R100(f300, 0);
+ R100(f300, 100);
+ R100(f300, 200);
+}
+
+static void __always_inline f400(int x __attribute__((unused)))
+{
+ STAP_PROBE1(test, usdt_400, 400);
+}
+
+/* this time we have 400 different USDT call sites, but they have uniform
+ * argument location, so libbpf's spec string deduplication logic should keep
+ * spec count use very small and so we should be able to attach to all 400
+ * call sites
+ */
+__weak void trigger_400_usdts(void)
+{
+ R100(f400, 0);
+ R100(f400, 100);
+ R100(f400, 200);
+ R100(f400, 300);
+}
+
+static void subtest_multispec_usdt(void)
+{
+ LIBBPF_OPTS(bpf_usdt_opts, opts);
+ struct test_usdt *skel;
+ struct test_usdt__bss *bss;
+ int err, i;
+
+ skel = test_usdt__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "skel_open"))
+ return;
+
+ bss = skel->bss;
+ bss->my_pid = getpid();
+
+ err = test_usdt__attach(skel);
+ if (!ASSERT_OK(err, "skel_attach"))
+ goto cleanup;
+
+ /* usdt_100 is auto-attached and there are 100 inlined call sites,
+ * let's validate that all of them are properly attached to and
+ * handled from BPF side
+ */
+ trigger_100_usdts();
+
+ ASSERT_EQ(bss->usdt_100_called, 100, "usdt_100_called");
+ ASSERT_EQ(bss->usdt_100_sum, 99 * 100 / 2, "usdt_100_sum");
+
+ /* Stress test free spec ID tracking. By default libbpf allows up to
+ * 256 specs to be used, so if we don't return free spec IDs back
+ * after few detachments and re-attachments we should run out of
+ * available spec IDs.
+ */
+ for (i = 0; i < 2; i++) {
+ bpf_link__destroy(skel->links.usdt_100);
+
+ skel->links.usdt_100 = bpf_program__attach_usdt(skel->progs.usdt_100, -1,
+ "/proc/self/exe",
+ "test", "usdt_100", NULL);
+ if (!ASSERT_OK_PTR(skel->links.usdt_100, "usdt_100_reattach"))
+ goto cleanup;
+
+ bss->usdt_100_sum = 0;
+ trigger_100_usdts();
+
+ ASSERT_EQ(bss->usdt_100_called, (i + 1) * 100 + 100, "usdt_100_called");
+ ASSERT_EQ(bss->usdt_100_sum, 99 * 100 / 2, "usdt_100_sum");
+ }
+
+ /* Now let's step it up and try to attach USDT that requires more than
+ * 256 attach points with different specs for each.
+ * Note that we need trigger_300_usdts() only to actually have 300
+ * USDT call sites, we are not going to actually trace them.
+ */
+ trigger_300_usdts();
+
+ /* we'll reuse usdt_100 BPF program for usdt_300 test */
+ bpf_link__destroy(skel->links.usdt_100);
+ skel->links.usdt_100 = bpf_program__attach_usdt(skel->progs.usdt_100, -1, "/proc/self/exe",
+ "test", "usdt_300", NULL);
+ err = -errno;
+ if (!ASSERT_ERR_PTR(skel->links.usdt_100, "usdt_300_bad_attach"))
+ goto cleanup;
+ ASSERT_EQ(err, -E2BIG, "usdt_300_attach_err");
+
+ /* let's check that there are no "dangling" BPF programs attached due
+ * to partial success of the above test:usdt_300 attachment
+ */
+ bss->usdt_100_called = 0;
+ bss->usdt_100_sum = 0;
+
+ f300(777); /* this is 301st instance of usdt_300 */
+
+ ASSERT_EQ(bss->usdt_100_called, 0, "usdt_301_called");
+ ASSERT_EQ(bss->usdt_100_sum, 0, "usdt_301_sum");
+
+ /* This time we have USDT with 400 inlined invocations, but arg specs
+ * should be the same across all sites, so libbpf will only need to
+ * use one spec and thus we'll be able to attach 400 uprobes
+ * successfully.
+ *
+ * Again, we are reusing usdt_100 BPF program.
+ */
+ skel->links.usdt_100 = bpf_program__attach_usdt(skel->progs.usdt_100, -1,
+ "/proc/self/exe",
+ "test", "usdt_400", NULL);
+ if (!ASSERT_OK_PTR(skel->links.usdt_100, "usdt_400_attach"))
+ goto cleanup;
+
+ trigger_400_usdts();
+
+ ASSERT_EQ(bss->usdt_100_called, 400, "usdt_400_called");
+ ASSERT_EQ(bss->usdt_100_sum, 400 * 400, "usdt_400_sum");
+
+cleanup:
+ test_usdt__destroy(skel);
+}
+
+static FILE *urand_spawn(int *pid)
+{
+ FILE *f;
+
+ /* urandom_read's stdout is wired into f */
+ f = popen("./urandom_read 1 report-pid", "r");
+ if (!f)
+ return NULL;
+
+ if (fscanf(f, "%d", pid) != 1) {
+ pclose(f);
+ errno = EINVAL;
+ return NULL;
+ }
+
+ return f;
+}
+
+static int urand_trigger(FILE **urand_pipe)
+{
+ int exit_code;
+
+ /* pclose() waits for child process to exit and returns their exit code */
+ exit_code = pclose(*urand_pipe);
+ *urand_pipe = NULL;
+
+ return exit_code;
+}
+
+static void subtest_urandom_usdt(bool auto_attach)
+{
+ struct test_urandom_usdt *skel;
+ struct test_urandom_usdt__bss *bss;
+ struct bpf_link *l;
+ FILE *urand_pipe = NULL;
+ int err, urand_pid = 0;
+
+ skel = test_urandom_usdt__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "skel_open"))
+ return;
+
+ urand_pipe = urand_spawn(&urand_pid);
+ if (!ASSERT_OK_PTR(urand_pipe, "urand_spawn"))
+ goto cleanup;
+
+ bss = skel->bss;
+ bss->urand_pid = urand_pid;
+
+ if (auto_attach) {
+ err = test_urandom_usdt__attach(skel);
+ if (!ASSERT_OK(err, "skel_auto_attach"))
+ goto cleanup;
+ } else {
+ l = bpf_program__attach_usdt(skel->progs.urand_read_without_sema,
+ urand_pid, "./urandom_read",
+ "urand", "read_without_sema", NULL);
+ if (!ASSERT_OK_PTR(l, "urand_without_sema_attach"))
+ goto cleanup;
+ skel->links.urand_read_without_sema = l;
+
+ l = bpf_program__attach_usdt(skel->progs.urand_read_with_sema,
+ urand_pid, "./urandom_read",
+ "urand", "read_with_sema", NULL);
+ if (!ASSERT_OK_PTR(l, "urand_with_sema_attach"))
+ goto cleanup;
+ skel->links.urand_read_with_sema = l;
+
+ l = bpf_program__attach_usdt(skel->progs.urandlib_read_without_sema,
+ urand_pid, "./liburandom_read.so",
+ "urandlib", "read_without_sema", NULL);
+ if (!ASSERT_OK_PTR(l, "urandlib_without_sema_attach"))
+ goto cleanup;
+ skel->links.urandlib_read_without_sema = l;
+
+ l = bpf_program__attach_usdt(skel->progs.urandlib_read_with_sema,
+ urand_pid, "./liburandom_read.so",
+ "urandlib", "read_with_sema", NULL);
+ if (!ASSERT_OK_PTR(l, "urandlib_with_sema_attach"))
+ goto cleanup;
+ skel->links.urandlib_read_with_sema = l;
+
+ }
+
+ /* trigger urandom_read USDTs */
+ ASSERT_OK(urand_trigger(&urand_pipe), "urand_exit_code");
+
+ ASSERT_EQ(bss->urand_read_without_sema_call_cnt, 1, "urand_wo_sema_cnt");
+ ASSERT_EQ(bss->urand_read_without_sema_buf_sz_sum, 256, "urand_wo_sema_sum");
+
+ ASSERT_EQ(bss->urand_read_with_sema_call_cnt, 1, "urand_w_sema_cnt");
+ ASSERT_EQ(bss->urand_read_with_sema_buf_sz_sum, 256, "urand_w_sema_sum");
+
+ ASSERT_EQ(bss->urandlib_read_without_sema_call_cnt, 1, "urandlib_wo_sema_cnt");
+ ASSERT_EQ(bss->urandlib_read_without_sema_buf_sz_sum, 256, "urandlib_wo_sema_sum");
+
+ ASSERT_EQ(bss->urandlib_read_with_sema_call_cnt, 1, "urandlib_w_sema_cnt");
+ ASSERT_EQ(bss->urandlib_read_with_sema_buf_sz_sum, 256, "urandlib_w_sema_sum");
+
+cleanup:
+ if (urand_pipe)
+ pclose(urand_pipe);
+ test_urandom_usdt__destroy(skel);
+}
+
+void test_usdt(void)
+{
+ if (test__start_subtest("basic"))
+ subtest_basic_usdt();
+ if (test__start_subtest("multispec"))
+ subtest_multispec_usdt();
+ if (test__start_subtest("urand_auto_attach"))
+ subtest_urandom_usdt(true /* auto_attach */);
+ if (test__start_subtest("urand_pid_attach"))
+ subtest_urandom_usdt(false /* auto_attach */);
+}