diff options
| author | Dave Marchevsky <davemarchevsky@fb.com> | 2022-10-20 09:07:20 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-10-21 19:23:34 -0700 |
| commit | 51ee71d38d8ce5a30496251200ab2f12b71e1fb6 (patch) | |
| tree | 8678c3ad0da143bac254b1c0053594a5f7c6023f /tools/testing/selftests/bpf/progs | |
| parent | d1673304097c1f5b04e062cf62fb40200ef1546b (diff) | |
selftests/bpf: Add test verifying bpf_ringbuf_reserve retval use in map ops
Add a test_ringbuf_map_key test prog, borrowing heavily from extant
test_ringbuf.c. The program tries to use the result of
bpf_ringbuf_reserve as map_key, which was not possible before previouis
commits in this series. The test runner added to prog_tests/ringbuf.c
verifies that the program loads and does basic sanity checks to confirm
that it runs as expected.
Also, refactor test_ringbuf such that runners for existing test_ringbuf
and newly-added test_ringbuf_map_key are subtests of 'ringbuf' top-level
test.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20221020160721.4030492-3-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/testing/selftests/bpf/progs')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_ringbuf_map_key.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf_map_key.c b/tools/testing/selftests/bpf/progs/test_ringbuf_map_key.c new file mode 100644 index 000000000000..2760bf60d05a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_ringbuf_map_key.c @@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */ + +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +char _license[] SEC("license") = "GPL"; + +struct sample { + int pid; + int seq; + long value; + char comm[16]; +}; + +struct { + __uint(type, BPF_MAP_TYPE_RINGBUF); +} ringbuf SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 1000); + __type(key, struct sample); + __type(value, int); +} hash_map SEC(".maps"); + +/* inputs */ +int pid = 0; + +/* inner state */ +long seq = 0; + +SEC("fentry/" SYS_PREFIX "sys_getpgid") +int test_ringbuf_mem_map_key(void *ctx) +{ + int cur_pid = bpf_get_current_pid_tgid() >> 32; + struct sample *sample, sample_copy; + int *lookup_val; + + if (cur_pid != pid) + return 0; + + sample = bpf_ringbuf_reserve(&ringbuf, sizeof(*sample), 0); + if (!sample) + return 0; + + sample->pid = pid; + bpf_get_current_comm(sample->comm, sizeof(sample->comm)); + sample->seq = ++seq; + sample->value = 42; + + /* test using 'sample' (PTR_TO_MEM | MEM_ALLOC) as map key arg + */ + lookup_val = (int *)bpf_map_lookup_elem(&hash_map, sample); + + /* workaround - memcpy is necessary so that verifier doesn't + * complain with: + * verifier internal error: more than one arg with ref_obj_id R3 + * when trying to do bpf_map_update_elem(&hash_map, sample, &sample->seq, BPF_ANY); + * + * Since bpf_map_lookup_elem above uses 'sample' as key, test using + * sample field as value below + */ + __builtin_memcpy(&sample_copy, sample, sizeof(struct sample)); + bpf_map_update_elem(&hash_map, &sample_copy, &sample->seq, BPF_ANY); + + bpf_ringbuf_submit(sample, 0); + return 0; +} |