summaryrefslogtreecommitdiffstats
path: root/samples/bpf/tracex6_user.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--samples/bpf/tracex6_user.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/samples/bpf/tracex6_user.c b/samples/bpf/tracex6_user.c
new file mode 100644
index 000000000..8e83bf2a8
--- /dev/null
+++ b/samples/bpf/tracex6_user.c
@@ -0,0 +1,222 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <fcntl.h>
+#include <linux/perf_event.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include "perf-sys.h"
+
+#define SAMPLE_PERIOD 0x7fffffffffffffffULL
+
+/* counters, values, values2 */
+static int map_fd[3];
+
+static void check_on_cpu(int cpu, struct perf_event_attr *attr)
+{
+ struct bpf_perf_event_value value2;
+ int pmu_fd, error = 0;
+ cpu_set_t set;
+ __u64 value;
+
+ /* Move to target CPU */
+ CPU_ZERO(&set);
+ CPU_SET(cpu, &set);
+ assert(sched_setaffinity(0, sizeof(set), &set) == 0);
+ /* Open perf event and attach to the perf_event_array */
+ pmu_fd = sys_perf_event_open(attr, -1/*pid*/, cpu/*cpu*/, -1/*group_fd*/, 0);
+ if (pmu_fd < 0) {
+ fprintf(stderr, "sys_perf_event_open failed on CPU %d\n", cpu);
+ error = 1;
+ goto on_exit;
+ }
+ assert(bpf_map_update_elem(map_fd[0], &cpu, &pmu_fd, BPF_ANY) == 0);
+ assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0) == 0);
+ /* Trigger the kprobe */
+ bpf_map_get_next_key(map_fd[1], &cpu, NULL);
+ /* Check the value */
+ if (bpf_map_lookup_elem(map_fd[1], &cpu, &value)) {
+ fprintf(stderr, "Value missing for CPU %d\n", cpu);
+ error = 1;
+ goto on_exit;
+ } else {
+ fprintf(stderr, "CPU %d: %llu\n", cpu, value);
+ }
+ /* The above bpf_map_lookup_elem should trigger the second kprobe */
+ if (bpf_map_lookup_elem(map_fd[2], &cpu, &value2)) {
+ fprintf(stderr, "Value2 missing for CPU %d\n", cpu);
+ error = 1;
+ goto on_exit;
+ } else {
+ fprintf(stderr, "CPU %d: counter: %llu, enabled: %llu, running: %llu\n", cpu,
+ value2.counter, value2.enabled, value2.running);
+ }
+
+on_exit:
+ assert(bpf_map_delete_elem(map_fd[0], &cpu) == 0 || error);
+ assert(ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE, 0) == 0 || error);
+ assert(close(pmu_fd) == 0 || error);
+ assert(bpf_map_delete_elem(map_fd[1], &cpu) == 0 || error);
+ exit(error);
+}
+
+static void test_perf_event_array(struct perf_event_attr *attr,
+ const char *name)
+{
+ int i, status, nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
+ pid_t pid[nr_cpus];
+ int err = 0;
+
+ printf("Test reading %s counters\n", name);
+
+ for (i = 0; i < nr_cpus; i++) {
+ pid[i] = fork();
+ assert(pid[i] >= 0);
+ if (pid[i] == 0) {
+ check_on_cpu(i, attr);
+ exit(1);
+ }
+ }
+
+ for (i = 0; i < nr_cpus; i++) {
+ assert(waitpid(pid[i], &status, 0) == pid[i]);
+ err |= status;
+ }
+
+ if (err)
+ printf("Test: %s FAILED\n", name);
+}
+
+static void test_bpf_perf_event(void)
+{
+ struct perf_event_attr attr_cycles = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_HARDWARE,
+ .read_format = 0,
+ .sample_type = 0,
+ .config = PERF_COUNT_HW_CPU_CYCLES,
+ };
+ struct perf_event_attr attr_clock = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_SOFTWARE,
+ .read_format = 0,
+ .sample_type = 0,
+ .config = PERF_COUNT_SW_CPU_CLOCK,
+ };
+ struct perf_event_attr attr_raw = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_RAW,
+ .read_format = 0,
+ .sample_type = 0,
+ /* Intel Instruction Retired */
+ .config = 0xc0,
+ };
+ struct perf_event_attr attr_l1d_load = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_HW_CACHE,
+ .read_format = 0,
+ .sample_type = 0,
+ .config =
+ PERF_COUNT_HW_CACHE_L1D |
+ (PERF_COUNT_HW_CACHE_OP_READ << 8) |
+ (PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16),
+ };
+ struct perf_event_attr attr_llc_miss = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_HW_CACHE,
+ .read_format = 0,
+ .sample_type = 0,
+ .config =
+ PERF_COUNT_HW_CACHE_LL |
+ (PERF_COUNT_HW_CACHE_OP_READ << 8) |
+ (PERF_COUNT_HW_CACHE_RESULT_MISS << 16),
+ };
+ struct perf_event_attr attr_msr_tsc = {
+ .freq = 0,
+ .sample_period = 0,
+ .inherit = 0,
+ /* From /sys/bus/event_source/devices/msr/ */
+ .type = 7,
+ .read_format = 0,
+ .sample_type = 0,
+ .config = 0,
+ };
+
+ test_perf_event_array(&attr_cycles, "HARDWARE-cycles");
+ test_perf_event_array(&attr_clock, "SOFTWARE-clock");
+ test_perf_event_array(&attr_raw, "RAW-instruction-retired");
+ test_perf_event_array(&attr_l1d_load, "HW_CACHE-L1D-load");
+
+ /* below tests may fail in qemu */
+ test_perf_event_array(&attr_llc_miss, "HW_CACHE-LLC-miss");
+ test_perf_event_array(&attr_msr_tsc, "Dynamic-msr-tsc");
+}
+
+int main(int argc, char **argv)
+{
+ struct bpf_link *links[2];
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ char filename[256];
+ int i = 0;
+
+ snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+ obj = bpf_object__open_file(filename, NULL);
+ if (libbpf_get_error(obj)) {
+ fprintf(stderr, "ERROR: opening BPF object file failed\n");
+ return 0;
+ }
+
+ /* load BPF program */
+ if (bpf_object__load(obj)) {
+ fprintf(stderr, "ERROR: loading BPF object file failed\n");
+ goto cleanup;
+ }
+
+ map_fd[0] = bpf_object__find_map_fd_by_name(obj, "counters");
+ map_fd[1] = bpf_object__find_map_fd_by_name(obj, "values");
+ map_fd[2] = bpf_object__find_map_fd_by_name(obj, "values2");
+ if (map_fd[0] < 0 || map_fd[1] < 0 || map_fd[2] < 0) {
+ fprintf(stderr, "ERROR: finding a map in obj file failed\n");
+ goto cleanup;
+ }
+
+ bpf_object__for_each_program(prog, obj) {
+ links[i] = bpf_program__attach(prog);
+ if (libbpf_get_error(links[i])) {
+ fprintf(stderr, "ERROR: bpf_program__attach failed\n");
+ links[i] = NULL;
+ goto cleanup;
+ }
+ i++;
+ }
+
+ test_bpf_perf_event();
+
+cleanup:
+ for (i--; i >= 0; i--)
+ bpf_link__destroy(links[i]);
+
+ bpf_object__close(obj);
+ return 0;
+}