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// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include "test_stacktrace_build_id.skel.h"
void test_stacktrace_build_id(void)
{
int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd;
struct test_stacktrace_build_id *skel;
int err, stack_trace_len, build_id_size;
__u32 key, prev_key, val, duration = 0;
char buf[BPF_BUILD_ID_SIZE];
struct bpf_stack_build_id id_offs[PERF_MAX_STACK_DEPTH];
int build_id_matches = 0;
int i, retry = 1;
retry:
skel = test_stacktrace_build_id__open_and_load();
if (CHECK(!skel, "skel_open_and_load", "skeleton open/load failed\n"))
return;
err = test_stacktrace_build_id__attach(skel);
if (CHECK(err, "attach_tp", "err %d\n", err))
goto cleanup;
/* find map fds */
control_map_fd = bpf_map__fd(skel->maps.control_map);
stackid_hmap_fd = bpf_map__fd(skel->maps.stackid_hmap);
stackmap_fd = bpf_map__fd(skel->maps.stackmap);
stack_amap_fd = bpf_map__fd(skel->maps.stack_amap);
if (CHECK_FAIL(system("dd if=/dev/urandom of=/dev/zero count=4 2> /dev/null")))
goto cleanup;
if (CHECK_FAIL(system("./urandom_read")))
goto cleanup;
/* disable stack trace collection */
key = 0;
val = 1;
bpf_map_update_elem(control_map_fd, &key, &val, 0);
/* for every element in stackid_hmap, we can find a corresponding one
* in stackmap, and vise versa.
*/
err = compare_map_keys(stackid_hmap_fd, stackmap_fd);
if (CHECK(err, "compare_map_keys stackid_hmap vs. stackmap",
"err %d errno %d\n", err, errno))
goto cleanup;
err = compare_map_keys(stackmap_fd, stackid_hmap_fd);
if (CHECK(err, "compare_map_keys stackmap vs. stackid_hmap",
"err %d errno %d\n", err, errno))
goto cleanup;
build_id_size = read_build_id("urandom_read", buf, sizeof(buf));
err = build_id_size < 0 ? build_id_size : 0;
if (CHECK(err, "read_build_id",
"err %d errno %d\n", err, errno))
goto cleanup;
err = bpf_map__get_next_key(skel->maps.stackmap, NULL, &key, sizeof(key));
if (CHECK(err, "get_next_key from stackmap",
"err %d, errno %d\n", err, errno))
goto cleanup;
do {
err = bpf_map_lookup_elem(stackmap_fd, &key, id_offs);
if (CHECK(err, "lookup_elem from stackmap",
"err %d, errno %d\n", err, errno))
goto cleanup;
for (i = 0; i < PERF_MAX_STACK_DEPTH; ++i)
if (id_offs[i].status == BPF_STACK_BUILD_ID_VALID &&
id_offs[i].offset != 0) {
if (memcmp(buf, id_offs[i].build_id, build_id_size) == 0)
build_id_matches = 1;
}
prev_key = key;
} while (bpf_map__get_next_key(skel->maps.stackmap, &prev_key, &key, sizeof(key)) == 0);
/* stack_map_get_build_id_offset() is racy and sometimes can return
* BPF_STACK_BUILD_ID_IP instead of BPF_STACK_BUILD_ID_VALID;
* try it one more time.
*/
if (build_id_matches < 1 && retry--) {
test_stacktrace_build_id__destroy(skel);
printf("%s:WARN:Didn't find expected build ID from the map, retrying\n",
__func__);
goto retry;
}
if (CHECK(build_id_matches < 1, "build id match",
"Didn't find expected build ID from the map\n"))
goto cleanup;
stack_trace_len = PERF_MAX_STACK_DEPTH *
sizeof(struct bpf_stack_build_id);
err = compare_stack_ips(stackmap_fd, stack_amap_fd, stack_trace_len);
CHECK(err, "compare_stack_ips stackmap vs. stack_amap",
"err %d errno %d\n", err, errno);
cleanup:
test_stacktrace_build_id__destroy(skel);
}
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