diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/missed.c')
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/missed.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/missed.c b/tools/testing/selftests/bpf/prog_tests/missed.c new file mode 100644 index 000000000000..70d90c43537c --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/missed.c @@ -0,0 +1,138 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <test_progs.h> +#include "missed_kprobe.skel.h" +#include "missed_kprobe_recursion.skel.h" +#include "missed_tp_recursion.skel.h" + +/* + * Putting kprobe on bpf_fentry_test1 that calls bpf_kfunc_common_test + * kfunc, which has also kprobe on. The latter won't get triggered due + * to kprobe recursion check and kprobe missed counter is incremented. + */ +static void test_missed_perf_kprobe(void) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct bpf_link_info info = {}; + struct missed_kprobe *skel; + __u32 len = sizeof(info); + int err, prog_fd; + + skel = missed_kprobe__open_and_load(); + if (!ASSERT_OK_PTR(skel, "missed_kprobe__open_and_load")) + goto cleanup; + + err = missed_kprobe__attach(skel); + if (!ASSERT_OK(err, "missed_kprobe__attach")) + goto cleanup; + + prog_fd = bpf_program__fd(skel->progs.trigger); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_run"); + ASSERT_EQ(topts.retval, 0, "test_run"); + + err = bpf_link_get_info_by_fd(bpf_link__fd(skel->links.test2), &info, &len); + if (!ASSERT_OK(err, "bpf_link_get_info_by_fd")) + goto cleanup; + + ASSERT_EQ(info.type, BPF_LINK_TYPE_PERF_EVENT, "info.type"); + ASSERT_EQ(info.perf_event.type, BPF_PERF_EVENT_KPROBE, "info.perf_event.type"); + ASSERT_EQ(info.perf_event.kprobe.missed, 1, "info.perf_event.kprobe.missed"); + +cleanup: + missed_kprobe__destroy(skel); +} + +static __u64 get_missed_count(int fd) +{ + struct bpf_prog_info info = {}; + __u32 len = sizeof(info); + int err; + + err = bpf_prog_get_info_by_fd(fd, &info, &len); + if (!ASSERT_OK(err, "bpf_prog_get_info_by_fd")) + return (__u64) -1; + return info.recursion_misses; +} + +/* + * Putting kprobe.multi on bpf_fentry_test1 that calls bpf_kfunc_common_test + * kfunc which has 3 perf event kprobes and 1 kprobe.multi attached. + * + * Because fprobe (kprobe.multi attach layear) does not have strict recursion + * check the kprobe's bpf_prog_active check is hit for test2-5. + */ +static void test_missed_kprobe_recursion(void) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct missed_kprobe_recursion *skel; + int err, prog_fd; + + skel = missed_kprobe_recursion__open_and_load(); + if (!ASSERT_OK_PTR(skel, "missed_kprobe_recursion__open_and_load")) + goto cleanup; + + err = missed_kprobe_recursion__attach(skel); + if (!ASSERT_OK(err, "missed_kprobe_recursion__attach")) + goto cleanup; + + prog_fd = bpf_program__fd(skel->progs.trigger); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_run"); + ASSERT_EQ(topts.retval, 0, "test_run"); + + ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test1)), 0, "test1_recursion_misses"); + ASSERT_GE(get_missed_count(bpf_program__fd(skel->progs.test2)), 1, "test2_recursion_misses"); + ASSERT_GE(get_missed_count(bpf_program__fd(skel->progs.test3)), 1, "test3_recursion_misses"); + ASSERT_GE(get_missed_count(bpf_program__fd(skel->progs.test4)), 1, "test4_recursion_misses"); + ASSERT_GE(get_missed_count(bpf_program__fd(skel->progs.test5)), 1, "test5_recursion_misses"); + +cleanup: + missed_kprobe_recursion__destroy(skel); +} + +/* + * Putting kprobe on bpf_fentry_test1 that calls bpf_printk and invokes + * bpf_trace_printk tracepoint. The bpf_trace_printk tracepoint has test[234] + * programs attached to it. + * + * Because kprobe execution goes through bpf_prog_active check, programs + * attached to the tracepoint will fail the recursion check and increment + * the recursion_misses stats. + */ +static void test_missed_tp_recursion(void) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct missed_tp_recursion *skel; + int err, prog_fd; + + skel = missed_tp_recursion__open_and_load(); + if (!ASSERT_OK_PTR(skel, "missed_tp_recursion__open_and_load")) + goto cleanup; + + err = missed_tp_recursion__attach(skel); + if (!ASSERT_OK(err, "missed_tp_recursion__attach")) + goto cleanup; + + prog_fd = bpf_program__fd(skel->progs.trigger); + err = bpf_prog_test_run_opts(prog_fd, &topts); + ASSERT_OK(err, "test_run"); + ASSERT_EQ(topts.retval, 0, "test_run"); + + ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test1)), 0, "test1_recursion_misses"); + ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test2)), 1, "test2_recursion_misses"); + ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test3)), 1, "test3_recursion_misses"); + ASSERT_EQ(get_missed_count(bpf_program__fd(skel->progs.test4)), 1, "test4_recursion_misses"); + +cleanup: + missed_tp_recursion__destroy(skel); +} + +void test_missed(void) +{ + if (test__start_subtest("perf_kprobe")) + test_missed_perf_kprobe(); + if (test__start_subtest("kprobe_recursion")) + test_missed_kprobe_recursion(); + if (test__start_subtest("tp_recursion")) + test_missed_tp_recursion(); +} |