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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 *file = "./test_stacktrace_map.o";
int bytes, efd, err, pmu_fd, prog_fd, stack_trace_len;
struct perf_event_attr attr = {};
__u32 key, val, duration = 0;
struct bpf_object *obj;
char buf[256];
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;
/* Get the ID for the sched/sched_switch tracepoint */
snprintf(buf, sizeof(buf),
"/sys/kernel/debug/tracing/events/sched/sched_switch/id");
efd = open(buf, O_RDONLY, 0);
if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno))
goto close_prog;
bytes = read(efd, buf, sizeof(buf));
close(efd);
if (bytes <= 0 || bytes >= sizeof(buf))
goto close_prog;
/* Open the perf event and attach bpf progrram */
attr.config = strtol(buf, NULL, 0);
attr.type = PERF_TYPE_TRACEPOINT;
attr.sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN;
attr.sample_period = 1;
attr.wakeup_events = 1;
pmu_fd = syscall(__NR_perf_event_open, &attr, -1 /* pid */,
0 /* cpu 0 */, -1 /* group id */,
0 /* flags */);
if (CHECK(pmu_fd < 0, "perf_event_open", "err %d errno %d\n",
pmu_fd, errno))
goto close_prog;
err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
if (err)
goto disable_pmu;
err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd);
if (err)
goto disable_pmu;
/* find map fds */
control_map_fd = bpf_find_map(__func__, obj, "control_map");
if (control_map_fd < 0)
goto disable_pmu;
stackid_hmap_fd = bpf_find_map(__func__, obj, "stackid_hmap");
if (stackid_hmap_fd < 0)
goto disable_pmu;
stackmap_fd = bpf_find_map(__func__, obj, "stackmap");
if (stackmap_fd < 0)
goto disable_pmu;
stack_amap_fd = bpf_find_map(__func__, obj, "stack_amap");
if (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_noerr;
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_noerr;
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_noerr;
goto disable_pmu_noerr;
disable_pmu:
error_cnt++;
disable_pmu_noerr:
ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE);
close(pmu_fd);
close_prog:
bpf_object__close(obj);
}
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