1 files changed, 369 insertions, 0 deletions

diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
new file mode 100644
index 000000000..e5832b74a
--- /dev/null
+++ b/tools/perf/tests/bpf.c
@@ -0,0 +1,369 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/epoll.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <util/record.h>
+#include <util/util.h>
+#include <util/bpf-loader.h>
+#include <util/evlist.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <api/fs/fs.h>
+#include <bpf/bpf.h>
+#include <perf/mmap.h>
+#include "tests.h"
+#include "llvm.h"
+#include "debug.h"
+#include "parse-events.h"
+#include "util/mmap.h"
+#define NR_ITERS       111
+#define PERF_TEST_BPF_PATH "/sys/fs/bpf/perf_test"
+
+#ifdef HAVE_LIBBPF_SUPPORT
+
+static int epoll_pwait_loop(void)
+{
+	int i;
+
+	/* Should fail NR_ITERS times */
+	for (i = 0; i < NR_ITERS; i++)
+		epoll_pwait(-(i + 1), NULL, 0, 0, NULL);
+	return 0;
+}
+
+#ifdef HAVE_BPF_PROLOGUE
+
+static int llseek_loop(void)
+{
+	int fds[2], i;
+
+	fds[0] = open("/dev/null", O_RDONLY);
+	fds[1] = open("/dev/null", O_RDWR);
+
+	if (fds[0] < 0 || fds[1] < 0)
+		return -1;
+
+	for (i = 0; i < NR_ITERS; i++) {
+		lseek(fds[i % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET);
+		lseek(fds[(i + 1) % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET);
+	}
+	close(fds[0]);
+	close(fds[1]);
+	return 0;
+}
+
+#endif
+
+static struct {
+	enum test_llvm__testcase prog_id;
+	const char *desc;
+	const char *name;
+	const char *msg_compile_fail;
+	const char *msg_load_fail;
+	int (*target_func)(void);
+	int expect_result;
+	bool	pin;
+} bpf_testcase_table[] = {
+	{
+		.prog_id	  = LLVM_TESTCASE_BASE,
+		.desc		  = "Basic BPF filtering",
+		.name		  = "[basic_bpf_test]",
+		.msg_compile_fail = "fix 'perf test LLVM' first",
+		.msg_load_fail	  = "load bpf object failed",
+		.target_func	  = &epoll_pwait_loop,
+		.expect_result	  = (NR_ITERS + 1) / 2,
+	},
+	{
+		.prog_id	  = LLVM_TESTCASE_BASE,
+		.desc		  = "BPF pinning",
+		.name		  = "[bpf_pinning]",
+		.msg_compile_fail = "fix kbuild first",
+		.msg_load_fail	  = "check your vmlinux setting?",
+		.target_func	  = &epoll_pwait_loop,
+		.expect_result	  = (NR_ITERS + 1) / 2,
+		.pin 		  = true,
+	},
+#ifdef HAVE_BPF_PROLOGUE
+	{
+		.prog_id	  = LLVM_TESTCASE_BPF_PROLOGUE,
+		.desc		  = "BPF prologue generation",
+		.name		  = "[bpf_prologue_test]",
+		.msg_compile_fail = "fix kbuild first",
+		.msg_load_fail	  = "check your vmlinux setting?",
+		.target_func	  = &llseek_loop,
+		.expect_result	  = (NR_ITERS + 1) / 4,
+	},
+#endif
+	{
+		.prog_id	  = LLVM_TESTCASE_BPF_RELOCATION,
+		.desc		  = "BPF relocation checker",
+		.name		  = "[bpf_relocation_test]",
+		.msg_compile_fail = "fix 'perf test LLVM' first",
+		.msg_load_fail	  = "libbpf error when dealing with relocation",
+	},
+};
+
+static int do_test(struct bpf_object *obj, int (*func)(void),
+		   int expect)
+{
+	struct record_opts opts = {
+		.target = {
+			.uid = UINT_MAX,
+			.uses_mmap = true,
+		},
+		.freq	      = 0,
+		.mmap_pages   = 256,
+		.default_interval = 1,
+	};
+
+	char pid[16];
+	char sbuf[STRERR_BUFSIZE];
+	struct evlist *evlist;
+	int i, ret = TEST_FAIL, err = 0, count = 0;
+
+	struct parse_events_state parse_state;
+	struct parse_events_error parse_error;
+
+	bzero(&parse_error, sizeof(parse_error));
+	bzero(&parse_state, sizeof(parse_state));
+	parse_state.error = &parse_error;
+	INIT_LIST_HEAD(&parse_state.list);
+
+	err = parse_events_load_bpf_obj(&parse_state, &parse_state.list, obj, NULL);
+	if (err || list_empty(&parse_state.list)) {
+		pr_debug("Failed to add events selected by BPF\n");
+		return TEST_FAIL;
+	}
+
+	snprintf(pid, sizeof(pid), "%d", getpid());
+	pid[sizeof(pid) - 1] = '\0';
+	opts.target.tid = opts.target.pid = pid;
+
+	/* Instead of perf_evlist__new_default, don't add default events */
+	evlist = evlist__new();
+	if (!evlist) {
+		pr_debug("Not enough memory to create evlist\n");
+		return TEST_FAIL;
+	}
+
+	err = perf_evlist__create_maps(evlist, &opts.target);
+	if (err < 0) {
+		pr_debug("Not enough memory to create thread/cpu maps\n");
+		goto out_delete_evlist;
+	}
+
+	perf_evlist__splice_list_tail(evlist, &parse_state.list);
+	evlist->nr_groups = parse_state.nr_groups;
+
+	perf_evlist__config(evlist, &opts, NULL);
+
+	err = evlist__open(evlist);
+	if (err < 0) {
+		pr_debug("perf_evlist__open: %s\n",
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
+		goto out_delete_evlist;
+	}
+
+	err = evlist__mmap(evlist, opts.mmap_pages);
+	if (err < 0) {
+		pr_debug("evlist__mmap: %s\n",
+			 str_error_r(errno, sbuf, sizeof(sbuf)));
+		goto out_delete_evlist;
+	}
+
+	evlist__enable(evlist);
+	(*func)();
+	evlist__disable(evlist);
+
+	for (i = 0; i < evlist->core.nr_mmaps; i++) {
+		union perf_event *event;
+		struct mmap *md;
+
+		md = &evlist->mmap[i];
+		if (perf_mmap__read_init(&md->core) < 0)
+			continue;
+
+		while ((event = perf_mmap__read_event(&md->core)) != NULL) {
+			const u32 type = event->header.type;
+
+			if (type == PERF_RECORD_SAMPLE)
+				count ++;
+		}
+		perf_mmap__read_done(&md->core);
+	}
+
+	if (count != expect * evlist->core.nr_entries) {
+		pr_debug("BPF filter result incorrect, expected %d, got %d samples\n", expect * evlist->core.nr_entries, count);
+		goto out_delete_evlist;
+	}
+
+	ret = TEST_OK;
+
+out_delete_evlist:
+	evlist__delete(evlist);
+	return ret;
+}
+
+static struct bpf_object *
+prepare_bpf(void *obj_buf, size_t obj_buf_sz, const char *name)
+{
+	struct bpf_object *obj;
+
+	obj = bpf__prepare_load_buffer(obj_buf, obj_buf_sz, name);
+	if (IS_ERR(obj)) {
+		pr_debug("Compile BPF program failed.\n");
+		return NULL;
+	}
+	return obj;
+}
+
+static int __test__bpf(int idx)
+{
+	int ret;
+	void *obj_buf;
+	size_t obj_buf_sz;
+	struct bpf_object *obj;
+
+	ret = test_llvm__fetch_bpf_obj(&obj_buf, &obj_buf_sz,
+				       bpf_testcase_table[idx].prog_id,
+				       true, NULL);
+	if (ret != TEST_OK || !obj_buf || !obj_buf_sz) {
+		pr_debug("Unable to get BPF object, %s\n",
+			 bpf_testcase_table[idx].msg_compile_fail);
+		if (idx == 0)
+			return TEST_SKIP;
+		else
+			return TEST_FAIL;
+	}
+
+	obj = prepare_bpf(obj_buf, obj_buf_sz,
+			  bpf_testcase_table[idx].name);
+	if ((!!bpf_testcase_table[idx].target_func) != (!!obj)) {
+		if (!obj)
+			pr_debug("Fail to load BPF object: %s\n",
+				 bpf_testcase_table[idx].msg_load_fail);
+		else
+			pr_debug("Success unexpectedly: %s\n",
+				 bpf_testcase_table[idx].msg_load_fail);
+		ret = TEST_FAIL;
+		goto out;
+	}
+
+	if (obj) {
+		ret = do_test(obj,
+			      bpf_testcase_table[idx].target_func,
+			      bpf_testcase_table[idx].expect_result);
+		if (ret != TEST_OK)
+			goto out;
+		if (bpf_testcase_table[idx].pin) {
+			int err;
+
+			if (!bpf_fs__mount()) {
+				pr_debug("BPF filesystem not mounted\n");
+				ret = TEST_FAIL;
+				goto out;
+			}
+			err = mkdir(PERF_TEST_BPF_PATH, 0777);
+			if (err && errno != EEXIST) {
+				pr_debug("Failed to make perf_test dir: %s\n",
+					 strerror(errno));
+				ret = TEST_FAIL;
+				goto out;
+			}
+			if (bpf_object__pin(obj, PERF_TEST_BPF_PATH))
+				ret = TEST_FAIL;
+			if (rm_rf(PERF_TEST_BPF_PATH))
+				ret = TEST_FAIL;
+		}
+	}
+
+out:
+	free(obj_buf);
+	bpf__clear();
+	return ret;
+}
+
+int test__bpf_subtest_get_nr(void)
+{
+	return (int)ARRAY_SIZE(bpf_testcase_table);
+}
+
+const char *test__bpf_subtest_get_desc(int i)
+{
+	if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table))
+		return NULL;
+	return bpf_testcase_table[i].desc;
+}
+
+static int check_env(void)
+{
+	int err;
+	unsigned int kver_int;
+	char license[] = "GPL";
+
+	struct bpf_insn insns[] = {
+		BPF_MOV64_IMM(BPF_REG_0, 1),
+		BPF_EXIT_INSN(),
+	};
+
+	err = fetch_kernel_version(&kver_int, NULL, 0);
+	if (err) {
+		pr_debug("Unable to get kernel version\n");
+		return err;
+	}
+
+	err = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
+			       sizeof(insns) / sizeof(insns[0]),
+			       license, kver_int, NULL, 0);
+	if (err < 0) {
+		pr_err("Missing basic BPF support, skip this test: %s\n",
+		       strerror(errno));
+		return err;
+	}
+	close(err);
+
+	return 0;
+}
+
+int test__bpf(struct test *test __maybe_unused, int i)
+{
+	int err;
+
+	if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table))
+		return TEST_FAIL;
+
+	if (geteuid() != 0) {
+		pr_debug("Only root can run BPF test\n");
+		return TEST_SKIP;
+	}
+
+	if (check_env())
+		return TEST_SKIP;
+
+	err = __test__bpf(i);
+	return err;
+}
+
+#else
+int test__bpf_subtest_get_nr(void)
+{
+	return 0;
+}
+
+const char *test__bpf_subtest_get_desc(int i __maybe_unused)
+{
+	return NULL;
+}
+
+int test__bpf(struct test *test __maybe_unused, int i __maybe_unused)
+{
+	pr_debug("Skip BPF test because BPF support is not compiled\n");
+	return TEST_SKIP;
+}
+#endif