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// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
void test_stacktrace_map(void)
{
int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd;
const char *prog_name = "tracepoint/sched/sched_switch";
int err, prog_fd, stack_trace_len;
const char *file = "./test_stacktrace_map.o";
__u32 key, val, duration = 0;
struct bpf_program *prog;
struct bpf_object *obj;
struct bpf_link *link;
err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd);
if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno))
return;
prog = bpf_object__find_program_by_title(obj, prog_name);
if (CHECK(!prog, "find_prog", "prog '%s' not found\n", prog_name))
goto close_prog;
link = bpf_program__attach_tracepoint(prog, "sched", "sched_switch");
if (CHECK(IS_ERR(link), "attach_tp", "err %ld\n", PTR_ERR(link)))
goto close_prog;
/* find map fds */
control_map_fd = bpf_find_map(__func__, obj, "control_map");
if (CHECK_FAIL(control_map_fd < 0))
goto disable_pmu;
stackid_hmap_fd = bpf_find_map(__func__, obj, "stackid_hmap");
if (CHECK_FAIL(stackid_hmap_fd < 0))
goto disable_pmu;
stackmap_fd = bpf_find_map(__func__, obj, "stackmap");
if (CHECK_FAIL(stackmap_fd < 0))
goto disable_pmu;
stack_amap_fd = bpf_find_map(__func__, obj, "stack_amap");
if (CHECK_FAIL(stack_amap_fd < 0))
goto disable_pmu;
/* give some time for bpf program run */
sleep(1);
/* 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 disable_pmu;
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 disable_pmu;
stack_trace_len = PERF_MAX_STACK_DEPTH * sizeof(__u64);
err = compare_stack_ips(stackmap_fd, stack_amap_fd, stack_trace_len);
if (CHECK(err, "compare_stack_ips stackmap vs. stack_amap",
"err %d errno %d\n", err, errno))
goto disable_pmu;
disable_pmu:
bpf_link__destroy(link);
close_prog:
bpf_object__close(obj);
}
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