brintos

brintos / linux-shallow public Read only

0
0
Text · 3.3 KiB · b7ba5cd Raw
104 lines · c
1// SPDX-License-Identifier: GPL-2.02#include <test_progs.h>3#include "test_stacktrace_build_id.skel.h"4 5void test_stacktrace_build_id(void)6{7 8	int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd;9	struct test_stacktrace_build_id *skel;10	int err, stack_trace_len, build_id_size;11	__u32 key, prev_key, val, duration = 0;12	char buf[BPF_BUILD_ID_SIZE];13	struct bpf_stack_build_id id_offs[PERF_MAX_STACK_DEPTH];14	int build_id_matches = 0;15	int i, retry = 1;16 17retry:18	skel = test_stacktrace_build_id__open_and_load();19	if (CHECK(!skel, "skel_open_and_load", "skeleton open/load failed\n"))20		return;21 22	err = test_stacktrace_build_id__attach(skel);23	if (CHECK(err, "attach_tp", "err %d\n", err))24		goto cleanup;25 26	/* find map fds */27	control_map_fd = bpf_map__fd(skel->maps.control_map);28	stackid_hmap_fd = bpf_map__fd(skel->maps.stackid_hmap);29	stackmap_fd = bpf_map__fd(skel->maps.stackmap);30	stack_amap_fd = bpf_map__fd(skel->maps.stack_amap);31 32	if (CHECK_FAIL(system("dd if=/dev/urandom of=/dev/zero count=4 2> /dev/null")))33		goto cleanup;34	if (CHECK_FAIL(system("./urandom_read")))35		goto cleanup;36	/* disable stack trace collection */37	key = 0;38	val = 1;39	bpf_map_update_elem(control_map_fd, &key, &val, 0);40 41	/* for every element in stackid_hmap, we can find a corresponding one42	 * in stackmap, and vise versa.43	 */44	err = compare_map_keys(stackid_hmap_fd, stackmap_fd);45	if (CHECK(err, "compare_map_keys stackid_hmap vs. stackmap",46		  "err %d errno %d\n", err, errno))47		goto cleanup;48 49	err = compare_map_keys(stackmap_fd, stackid_hmap_fd);50	if (CHECK(err, "compare_map_keys stackmap vs. stackid_hmap",51		  "err %d errno %d\n", err, errno))52		goto cleanup;53 54	build_id_size = read_build_id("urandom_read", buf, sizeof(buf));55	err = build_id_size < 0 ? build_id_size : 0;56 57	if (CHECK(err, "read_build_id",58		  "err %d errno %d\n", err, errno))59		goto cleanup;60 61	err = bpf_map__get_next_key(skel->maps.stackmap, NULL, &key, sizeof(key));62	if (CHECK(err, "get_next_key from stackmap",63		  "err %d, errno %d\n", err, errno))64		goto cleanup;65 66	do {67		err = bpf_map_lookup_elem(stackmap_fd, &key, id_offs);68		if (CHECK(err, "lookup_elem from stackmap",69			  "err %d, errno %d\n", err, errno))70			goto cleanup;71		for (i = 0; i < PERF_MAX_STACK_DEPTH; ++i)72			if (id_offs[i].status == BPF_STACK_BUILD_ID_VALID &&73			    id_offs[i].offset != 0) {74				if (memcmp(buf, id_offs[i].build_id, build_id_size) == 0)75					build_id_matches = 1;76			}77		prev_key = key;78	} while (bpf_map__get_next_key(skel->maps.stackmap, &prev_key, &key, sizeof(key)) == 0);79 80	/* stack_map_get_build_id_offset() is racy and sometimes can return81	 * BPF_STACK_BUILD_ID_IP instead of BPF_STACK_BUILD_ID_VALID;82	 * try it one more time.83	 */84	if (build_id_matches < 1 && retry--) {85		test_stacktrace_build_id__destroy(skel);86		printf("%s:WARN:Didn't find expected build ID from the map, retrying\n",87		       __func__);88		goto retry;89	}90 91	if (CHECK(build_id_matches < 1, "build id match",92		  "Didn't find expected build ID from the map\n"))93		goto cleanup;94 95	stack_trace_len = PERF_MAX_STACK_DEPTH *96			  sizeof(struct bpf_stack_build_id);97	err = compare_stack_ips(stackmap_fd, stack_amap_fd, stack_trace_len);98	CHECK(err, "compare_stack_ips stackmap vs. stack_amap",99	      "err %d errno %d\n", err, errno);100 101cleanup:102	test_stacktrace_build_id__destroy(skel);103}104