On 1/31/24 9:20 AM, Andrii Nakryiko wrote:
On Tue, Jan 30, 2024 at 9:30 PM Yonghong Song <yonghong.song@xxxxxxxxx> wrote:
On 1/30/24 11:36 AM, Andrii Nakryiko wrote:
Seems like original commit adding split BTF support intended to add
btf__new_split() API, and even declared it in libbpf.map, but never
added (trivial) implementation. Fix this.
Fixes: ba451366bf44 ("libbpf: Implement basic split BTF support")
Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
The patch LGTM. We did some cross checking between libbpf.map
and the implementation. What things are missing here to
capture missed implementation or LIBBPF_API marking?
Yes, we still have it, and it does detect issues when API wasn't added
into libbpf.map.
I haven't investigated exactly why it didn't catch the issue when API
is in libbpf.map, but is not marked with LIBBPF_API, but I suspect
it's because existing check doesn't take into account visibility of
the symbol, so there is some room for improvement.
Similarly, not sure why it didn't detect that btf_ext__new_split()
wasn't even implemented, probably because we don't distinguish UNDEF
and FUNC symbols? So something to follow up on for sure.
Agreed. A followup to improve API matching between libbpf.map and code
can be done later.
Acked-by: Yonghong Song <yonghong.song@xxxxxxxxx>
---
tools/lib/bpf/btf.c | 5 +++++
tools/lib/bpf/libbpf.map | 3 ++-
2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 95db88b36cf3..845034d15420 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -1079,6 +1079,11 @@ struct btf *btf__new(const void *data, __u32 size)
return libbpf_ptr(btf_new(data, size, NULL));
}
+struct btf *btf__new_split(const void *data, __u32 size, struct btf *base_btf)
+{
+ return libbpf_ptr(btf_new(data, size, base_btf));
+}
+
static struct btf *btf_parse_elf(const char *path, struct btf *base_btf,
struct btf_ext **btf_ext)
{
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index d9e1f57534fa..386964f572a8 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -245,7 +245,6 @@ LIBBPF_0.3.0 {
btf__parse_raw_split;
btf__parse_split;
btf__new_empty_split;
- btf__new_split;
ring_buffer__epoll_fd;
} LIBBPF_0.2.0;
@@ -411,5 +410,7 @@ LIBBPF_1.3.0 {
} LIBBPF_1.2.0;
LIBBPF_1.4.0 {
+ global:
bpf_token_create;
+ btf__new_split;
} LIBBPF_1.3.0;
