[PATCH v3 bpf-next 4/4] tracing/probe: Add self test for PERF_EVENT_IOC_QUERY_PROBE

From: Daniel Xu
Date: Fri Aug 16 2019 - 18:32:26 EST


Acked-by: Andrii Nakryiko <andriin@xxxxxx>
Signed-off-by: Daniel Xu <dxu@xxxxxxxxx>
---
.../selftests/bpf/prog_tests/attach_probe.c | 106 ++++++++++++++++++
1 file changed, 106 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
index 5ecc267d98b0..c14db7557881 100644
--- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c
+++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
@@ -27,17 +27,27 @@ void test_attach_probe(void)
const char *kretprobe_name = "kretprobe/sys_nanosleep";
const char *uprobe_name = "uprobe/trigger_func";
const char *uretprobe_name = "uretprobe/trigger_func";
+ struct perf_event_query_probe kprobe_query = {};
+ struct perf_event_query_probe kretprobe_query = {};
+ struct perf_event_query_probe uprobe_query = {};
+ struct perf_event_query_probe uretprobe_query = {};
const int kprobe_idx = 0, kretprobe_idx = 1;
const int uprobe_idx = 2, uretprobe_idx = 3;
const char *file = "./test_attach_probe.o";
struct bpf_program *kprobe_prog, *kretprobe_prog;
struct bpf_program *uprobe_prog, *uretprobe_prog;
struct bpf_object *obj;
+ const struct bpf_link_fd *kprobe_fd_link;
+ const struct bpf_link_fd *kretprobe_fd_link;
+ const struct bpf_link_fd *uprobe_fd_link;
+ const struct bpf_link_fd *uretprobe_fd_link;
int err, prog_fd, duration = 0, res;
struct bpf_link *kprobe_link = NULL;
struct bpf_link *kretprobe_link = NULL;
struct bpf_link *uprobe_link = NULL;
struct bpf_link *uretprobe_link = NULL;
+ int kprobe_fd, kretprobe_fd;
+ int uprobe_fd, uretprobe_fd;
int results_map_fd;
size_t uprobe_offset;
ssize_t base_addr;
@@ -116,6 +126,54 @@ void test_attach_probe(void)
/* trigger & validate kprobe && kretprobe */
usleep(1);

+ kprobe_fd_link = bpf_link__as_fd(kprobe_link);
+ if (CHECK(!kprobe_fd_link, "kprobe_link_as_fd",
+ "failed to cast link to fd link\n"))
+ goto cleanup;
+
+ kprobe_fd = bpf_link_fd__fd(kprobe_fd_link);
+ if (CHECK(kprobe_fd < 0, "kprobe_get_perf_fd",
+ "failed to get perf fd from kprobe link\n"))
+ goto cleanup;
+
+ kretprobe_fd_link = bpf_link__as_fd(kretprobe_link);
+ if (CHECK(!kretprobe_fd_link, "kretprobe_link_as_fd",
+ "failed to cast link to fd link\n"))
+ goto cleanup;
+
+ kretprobe_fd = bpf_link_fd__fd(kretprobe_fd_link);
+ if (CHECK(kretprobe_fd < 0, "kretprobe_get_perf_fd",
+ "failed to get perf fd from kretprobe link\n"))
+ goto cleanup;
+
+ kprobe_query.size = sizeof(kprobe_query);
+ err = ioctl(kprobe_fd, PERF_EVENT_IOC_QUERY_PROBE, &kprobe_query);
+ if (CHECK(err, "get_kprobe_ioctl",
+ "failed to issue kprobe query ioctl\n"))
+ goto cleanup;
+ if (CHECK(kprobe_query.nmissed > 0, "get_kprobe_ioctl",
+ "read incorrect nmissed from kprobe_ioctl: %llu\n",
+ kprobe_query.nmissed))
+ goto cleanup;
+ if (CHECK(kprobe_query.nhit == 0, "get_kprobe_ioctl",
+ "read incorrect nhit from kprobe_ioctl: %llu\n",
+ kprobe_query.nhit))
+ goto cleanup;
+
+ kretprobe_query.size = sizeof(kretprobe_query);
+ err = ioctl(kretprobe_fd, PERF_EVENT_IOC_QUERY_PROBE, &kretprobe_query);
+ if (CHECK(err, "get_kretprobe_ioctl",
+ "failed to issue kretprobe query ioctl\n"))
+ goto cleanup;
+ if (CHECK(kretprobe_query.nmissed > 0, "get_kretprobe_ioctl",
+ "read incorrect nmissed from kretprobe_ioctl: %llu\n",
+ kretprobe_query.nmissed))
+ goto cleanup;
+ if (CHECK(kretprobe_query.nhit <= 0, "get_kretprobe_ioctl",
+ "read incorrect nhit from kretprobe_ioctl: %llu\n",
+ kretprobe_query.nhit))
+ goto cleanup;
+
err = bpf_map_lookup_elem(results_map_fd, &kprobe_idx, &res);
if (CHECK(err, "get_kprobe_res",
"failed to get kprobe res: %d\n", err))
@@ -135,6 +193,54 @@ void test_attach_probe(void)
/* trigger & validate uprobe & uretprobe */
get_base_addr();

+ uprobe_fd_link = bpf_link__as_fd(uprobe_link);
+ if (CHECK(!uprobe_fd_link, "uprobe_link_as_fd",
+ "failed to cast link to fd link\n"))
+ goto cleanup;
+
+ uprobe_fd = bpf_link_fd__fd(uprobe_fd_link);
+ if (CHECK(uprobe_fd < 0, "uprobe_get_perf_fd",
+ "failed to get perf fd from uprobe link\n"))
+ goto cleanup;
+
+ uretprobe_fd_link = bpf_link__as_fd(uretprobe_link);
+ if (CHECK(!uretprobe_fd_link, "uretprobe_link_as_fd",
+ "failed to cast link to fd link\n"))
+ goto cleanup;
+
+ uretprobe_fd = bpf_link_fd__fd(uretprobe_fd_link);
+ if (CHECK(uretprobe_fd < 0, "uretprobe_get_perf_fd",
+ "failed to get perf fd from uretprobe link\n"))
+ goto cleanup;
+
+ uprobe_query.size = sizeof(uprobe_query);
+ err = ioctl(uprobe_fd, PERF_EVENT_IOC_QUERY_PROBE, &uprobe_query);
+ if (CHECK(err, "get_uprobe_ioctl",
+ "failed to issue uprobe query ioctl\n"))
+ goto cleanup;
+ if (CHECK(uprobe_query.nmissed > 0, "get_uprobe_ioctl",
+ "read incorrect nmissed from uprobe_ioctl: %llu\n",
+ uprobe_query.nmissed))
+ goto cleanup;
+ if (CHECK(uprobe_query.nhit == 0, "get_uprobe_ioctl",
+ "read incorrect nhit from uprobe_ioctl: %llu\n",
+ uprobe_query.nhit))
+ goto cleanup;
+
+ uretprobe_query.size = sizeof(uretprobe_query);
+ err = ioctl(uretprobe_fd, PERF_EVENT_IOC_QUERY_PROBE, &uretprobe_query);
+ if (CHECK(err, "get_uretprobe_ioctl",
+ "failed to issue uretprobe query ioctl\n"))
+ goto cleanup;
+ if (CHECK(uretprobe_query.nmissed > 0, "get_uretprobe_ioctl",
+ "read incorrect nmissed from uretprobe_ioctl: %llu\n",
+ uretprobe_query.nmissed))
+ goto cleanup;
+ if (CHECK(uretprobe_query.nhit <= 0, "get_uretprobe_ioctl",
+ "read incorrect nhit from uretprobe_ioctl: %llu\n",
+ uretprobe_query.nhit))
+ goto cleanup;
+
err = bpf_map_lookup_elem(results_map_fd, &uprobe_idx, &res);
if (CHECK(err, "get_uprobe_res",
"failed to get uprobe res: %d\n", err))
--
2.20.1