brintos

brintos / linux-shallow public Read only

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1// SPDX-License-Identifier: GPL-2.02#define _GNU_SOURCE3#include <pthread.h>4#include <sched.h>5#include <sys/socket.h>6#include <test_progs.h>7#include "test_perf_buffer.skel.h"8#include "bpf/libbpf_internal.h"9 10static int duration;11 12/* AddressSanitizer sometimes crashes due to data dereference below, due to13 * this being mmap()'ed memory. Disable instrumentation with14 * no_sanitize_address attribute15 */16__attribute__((no_sanitize_address))17static void on_sample(void *ctx, int cpu, void *data, __u32 size)18{19	int cpu_data = *(int *)data, duration = 0;20	cpu_set_t *cpu_seen = ctx;21 22	if (cpu_data != cpu)23		CHECK(cpu_data != cpu, "check_cpu_data",24		      "cpu_data %d != cpu %d\n", cpu_data, cpu);25 26	CPU_SET(cpu, cpu_seen);27}28 29int trigger_on_cpu(int cpu)30{31	cpu_set_t cpu_set;32	int err;33 34	CPU_ZERO(&cpu_set);35	CPU_SET(cpu, &cpu_set);36 37	err = pthread_setaffinity_np(pthread_self(), sizeof(cpu_set), &cpu_set);38	if (err && CHECK(err, "set_affinity", "cpu #%d, err %d\n", cpu, err))39		return err;40 41	usleep(1);42 43	return 0;44}45 46void serial_test_perf_buffer(void)47{48	int err, on_len, nr_on_cpus = 0, nr_cpus, i, j;49	int zero = 0, my_pid = getpid();50	struct test_perf_buffer *skel;51	cpu_set_t cpu_seen;52	struct perf_buffer *pb;53	int last_fd = -1, fd;54	bool *online;55 56	nr_cpus = libbpf_num_possible_cpus();57	if (CHECK(nr_cpus < 0, "nr_cpus", "err %d\n", nr_cpus))58		return;59 60	err = parse_cpu_mask_file("/sys/devices/system/cpu/online",61				  &online, &on_len);62	if (CHECK(err, "nr_on_cpus", "err %d\n", err))63		return;64 65	for (i = 0; i < on_len; i++)66		if (online[i])67			nr_on_cpus++;68 69	/* load program */70	skel = test_perf_buffer__open_and_load();71	if (CHECK(!skel, "skel_load", "skeleton open/load failed\n"))72		goto out_close;73 74	err = bpf_map_update_elem(bpf_map__fd(skel->maps.my_pid_map), &zero, &my_pid, 0);75	if (!ASSERT_OK(err, "my_pid_update"))76		goto out_close;77 78	/* attach probe */79	err = test_perf_buffer__attach(skel);80	if (CHECK(err, "attach_kprobe", "err %d\n", err))81		goto out_close;82 83	/* set up perf buffer */84	pb = perf_buffer__new(bpf_map__fd(skel->maps.perf_buf_map), 1,85			      on_sample, NULL, &cpu_seen, NULL);86	if (!ASSERT_OK_PTR(pb, "perf_buf__new"))87		goto out_close;88 89	CHECK(perf_buffer__epoll_fd(pb) < 0, "epoll_fd",90	      "bad fd: %d\n", perf_buffer__epoll_fd(pb));91 92	/* trigger kprobe on every CPU */93	CPU_ZERO(&cpu_seen);94	for (i = 0; i < nr_cpus; i++) {95		if (i >= on_len || !online[i]) {96			printf("skipping offline CPU #%d\n", i);97			continue;98		}99 100		if (trigger_on_cpu(i))101			goto out_close;102	}103 104	/* read perf buffer */105	err = perf_buffer__poll(pb, 100);106	if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err))107		goto out_free_pb;108 109	if (CHECK(CPU_COUNT(&cpu_seen) != nr_on_cpus, "seen_cpu_cnt",110		  "expect %d, seen %d\n", nr_on_cpus, CPU_COUNT(&cpu_seen)))111		goto out_free_pb;112 113	if (CHECK(perf_buffer__buffer_cnt(pb) != nr_on_cpus, "buf_cnt",114		  "got %zu, expected %d\n", perf_buffer__buffer_cnt(pb), nr_on_cpus))115		goto out_close;116 117	for (i = 0, j = 0; i < nr_cpus; i++) {118		if (i >= on_len || !online[i])119			continue;120 121		fd = perf_buffer__buffer_fd(pb, j);122		CHECK(fd < 0 || last_fd == fd, "fd_check", "last fd %d == fd %d\n", last_fd, fd);123		last_fd = fd;124 125		err = perf_buffer__consume_buffer(pb, j);126		if (CHECK(err, "drain_buf", "cpu %d, err %d\n", i, err))127			goto out_close;128 129		CPU_CLR(i, &cpu_seen);130		if (trigger_on_cpu(i))131			goto out_close;132 133		err = perf_buffer__consume_buffer(pb, j);134		if (CHECK(err, "consume_buf", "cpu %d, err %d\n", j, err))135			goto out_close;136 137		if (CHECK(!CPU_ISSET(i, &cpu_seen), "cpu_seen", "cpu %d not seen\n", i))138			goto out_close;139		j++;140	}141 142out_free_pb:143	perf_buffer__free(pb);144out_close:145	test_perf_buffer__destroy(skel);146	free(online);147}148