6 files changed, 248 insertions, 1 deletions

diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index a47b21193fb2..f41ebf8849fe 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -32,6 +32,7 @@ perf-y += parse-no-sample-id-all.o
 perf-y += kmod-path.o
 perf-y += thread-map.o
 perf-y += llvm.o llvm-src-base.o llvm-src-kbuild.o
+perf-y += bpf.o
 perf-y += topology.o
 
 $(OUTPUT)tests/llvm-src-base.c: tests/bpf-script-example.c
diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
new file mode 100644
index 000000000000..ec16f7812c8b
--- /dev/null
+++ b/tools/perf/tests/bpf.c
@@ -0,0 +1,209 @@
+#include <stdio.h>
+#include <sys/epoll.h>
+#include <util/bpf-loader.h>
+#include <util/evlist.h>
+#include "tests.h"
+#include "llvm.h"
+#include "debug.h"
+#define NR_ITERS       111
+
+#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;
+}
+
+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;
+} bpf_testcase_table[] = {
+        {
+                LLVM_TESTCASE_BASE,
+                "Test basic BPF filtering",
+                "[basic_bpf_test]",
+                "fix 'perf test LLVM' first",
+                "load bpf object failed",
+                &epoll_pwait_loop,
+                (NR_ITERS + 1) / 2,
+        },
+};
+
+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 perf_evlist *evlist;
+        int i, ret = TEST_FAIL, err = 0, count = 0;
+
+        struct parse_events_evlist parse_evlist;
+        struct parse_events_error parse_error;
+
+        bzero(&parse_error, sizeof(parse_error));
+        bzero(&parse_evlist, sizeof(parse_evlist));
+        parse_evlist.error = &parse_error;
+        INIT_LIST_HEAD(&parse_evlist.list);
+
+        err = parse_events_load_bpf_obj(&parse_evlist, &parse_evlist.list, obj);
+        if (err || list_empty(&parse_evlist.list)) {
+                pr_debug("Failed to add events selected by BPF\n");
+                if (!err)
+                        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 = perf_evlist__new();
+        if (!evlist) {
+                pr_debug("No ehough 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_evlist.list);
+        evlist->nr_groups = parse_evlist.nr_groups;
+
+        perf_evlist__config(evlist, &opts);
+
+        err = perf_evlist__open(evlist);
+        if (err < 0) {
+                pr_debug("perf_evlist__open: %s\n",
+                         strerror_r(errno, sbuf, sizeof(sbuf)));
+                goto out_delete_evlist;
+        }
+
+        err = perf_evlist__mmap(evlist, opts.mmap_pages, false);
+        if (err < 0) {
+                pr_debug("perf_evlist__mmap: %s\n",
+                         strerror_r(errno, sbuf, sizeof(sbuf)));
+                goto out_delete_evlist;
+        }
+
+        perf_evlist__enable(evlist);
+        (*func)();
+        perf_evlist__disable(evlist);
+
+        for (i = 0; i < evlist->nr_mmaps; i++) {
+                union perf_event *event;
+
+                while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
+                        const u32 type = event->header.type;
+
+                        if (type == PERF_RECORD_SAMPLE)
+                                count ++;
+                }
+        }
+
+        if (count != expect)
+                pr_debug("BPF filter result incorrect\n");
+
+        ret = TEST_OK;
+
+out_delete_evlist:
+        perf_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 index)
+{
+        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[index].prog_id,
+                                       true);
+        if (ret != TEST_OK || !obj_buf || !obj_buf_sz) {
+                pr_debug("Unable to get BPF object, %s\n",
+                         bpf_testcase_table[index].msg_compile_fail);
+                if (index == 0)
+                        return TEST_SKIP;
+                else
+                        return TEST_FAIL;
+        }
+
+        obj = prepare_bpf(obj_buf, obj_buf_sz,
+                          bpf_testcase_table[index].name);
+        if (!obj) {
+                ret = TEST_FAIL;
+                goto out;
+        }
+
+        ret = do_test(obj,
+                      bpf_testcase_table[index].target_func,
+                      bpf_testcase_table[index].expect_result);
+out:
+        bpf__clear();
+        return ret;
+}
+
+int test__bpf(void)
+{
+        unsigned int i;
+        int err;
+
+        if (geteuid() != 0) {
+                pr_debug("Only root can run BPF test\n");
+                return TEST_SKIP;
+        }
+
+        for (i = 0; i < ARRAY_SIZE(bpf_testcase_table); i++) {
+                err = __test__bpf(i);
+
+                if (err != TEST_OK)
+                        return err;
+        }
+
+        return TEST_OK;
+}
+
+#else
+int test__bpf(void)
+{
+        pr_debug("Skip BPF test because BPF support is not compiled\n");
+        return TEST_SKIP;
+}
+#endif
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 66f72d3d6677..7b0120abc137 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -166,6 +166,10 @@ static struct test generic_tests[] = {
                 .func = test_session_topology,
         },
         {
+                .desc = "Test BPF filter",
+                .func = test__bpf,
+        },
+        {
                 .func = NULL,
         },
 };
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index c80486969f83..3c8734a3abbc 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -66,6 +66,7 @@ int test__fdarray__add(void);
 int test__kmod_path__parse(void);
 int test__thread_map(void);
 int test__llvm(void);
+int test__bpf(void);
 int test_session_topology(void);
 
 #if defined(__arm__) || defined(__aarch64__)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index e3afa1b60bb5..4c50411371db 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -34,10 +34,32 @@ struct bpf_prog_priv {
         struct perf_probe_event pev;
 };
 
+static bool libbpf_initialized;
+
+struct bpf_object *
+bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, const char *name)
+{
+        struct bpf_object *obj;
+
+        if (!libbpf_initialized) {
+                libbpf_set_print(libbpf_warning,
+                                 libbpf_info,
+                                 libbpf_debug);
+                libbpf_initialized = true;
+        }
+
+        obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, name);
+        if (IS_ERR(obj)) {
+                pr_debug("bpf: failed to load buffer\n");
+                return ERR_PTR(-EINVAL);
+        }
+
+        return obj;
+}
+
 struct bpf_object *bpf__prepare_load(const char *filename, bool source)
 {
         struct bpf_object *obj;
-        static bool libbpf_initialized;
 
         if (!libbpf_initialized) {
                 libbpf_set_print(libbpf_warning,
diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h
index 5eb3629eed8b..9caf3ae4acf3 100644
--- a/tools/perf/util/bpf-loader.h
+++ b/tools/perf/util/bpf-loader.h
@@ -34,6 +34,9 @@ struct bpf_object *bpf__prepare_load(const char *filename, bool source);
 int bpf__strerror_prepare_load(const char *filename, bool source,
                                int err, char *buf, size_t size);
 
+struct bpf_object *bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz,
+                                            const char *name);
+
 void bpf__clear(void);
 
 int bpf__probe(struct bpf_object *obj);
@@ -55,6 +58,13 @@ bpf__prepare_load(const char *filename __maybe_unused,
         return ERR_PTR(-ENOTSUP);
 }
 
+static inline struct bpf_object *
+bpf__prepare_load_buffer(void *obj_buf __maybe_unused,
+                                           size_t obj_buf_sz __maybe_unused)
+{
+        return ERR_PTR(-ENOTSUP);
+}
+
 static inline void bpf__clear(void) { }
 
 static inline int bpf__probe(struct bpf_object *obj __maybe_unused) { return 0;}