Add the testing to access the bpf_ringbuf with the map pointer. "consumer_pos" and "producer_pos" is accessed in this testing. We reserve 128 bytes in the ringbuf to test the producer_pos, which should be "128 + 8", and the "8" is BPF_RINGBUF_HDR_SZ.
It will be helpful if we want to evaluate the usage of the ringbuf in bpf prog with the consumer and producer position. Signed-off-by: Menglong Dong <[email protected]> Reviewed-by: Emil Tsalapatis <[email protected]> --- v2: - don't set the max_entries for the ringbuf map - add comment for the producer_pos --- .../testing/selftests/bpf/progs/map_ptr_kern.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c index efaf622c28dd..d7611e7018ca 100644 --- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c +++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c @@ -647,8 +647,14 @@ static inline int check_devmap_hash(void) return 1; } +struct bpf_ringbuf { + unsigned long consumer_pos; + unsigned long producer_pos; +} __attribute__((preserve_access_index)); + struct bpf_ringbuf_map { struct bpf_map map; + struct bpf_ringbuf *rb; } __attribute__((preserve_access_index)); struct { @@ -659,9 +665,21 @@ static inline int check_ringbuf(void) { struct bpf_ringbuf_map *ringbuf = (struct bpf_ringbuf_map *)&m_ringbuf; struct bpf_map *map = (struct bpf_map *)&m_ringbuf; + struct bpf_ringbuf *rb; + void *ptr; VERIFY(check(&ringbuf->map, map, 0, 0, page_size)); + ptr = bpf_ringbuf_reserve(&m_ringbuf, 128, 0); + VERIFY(ptr); + + bpf_ringbuf_discard(ptr, 0); + rb = ringbuf->rb; + VERIFY(rb); + VERIFY(rb->consumer_pos == 0); + /* The "8" here is BPF_RINGBUF_HDR_SZ */ + VERIFY(rb->producer_pos == 128 + 8); + return 1; } -- 2.53.0
