On 11/9/23 17:35, Martin KaFai Lau wrote:
On 11/6/23 12:12 PM, thinker.li@xxxxxxxxx wrote:
From: Kui-Feng Lee <thinker.li@xxxxxxxxx>
Maintain a registry of registered struct_ops types in the per-btf
(module)
struct_ops_tab. This registry allows for easy lookup of struct_ops types
that are registered by a specific module.
It is a preparation work for supporting kernel module struct_ops in a
latter patch. Each struct_ops will be registered under its own kernel
module btf and will be stored in the newly added btf->struct_ops_tab. The
bpf verifier and bpf syscall (e.g. prog and map cmd) can find the
struct_ops and its btf type/size/id... information from
btf->struct_ops_tab.
Signed-off-by: Kui-Feng Lee <thinker.li@xxxxxxxxx>
---
include/linux/btf.h | 8 +++++
kernel/bpf/btf.c | 83 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 91 insertions(+)
diff --git a/include/linux/btf.h b/include/linux/btf.h
index c2231c64d60b..07ee6740e06a 100644
--- a/include/linux/btf.h
+++ b/include/linux/btf.h
@@ -572,4 +572,12 @@ static inline bool btf_type_is_struct_ptr(struct
btf *btf, const struct btf_type
return btf_type_is_struct(t);
}
+#ifdef CONFIG_BPF_JIT
There are many new ifdef CONFIG_BPF_JIT in btf.{h,c}. Could it be
avoided? For example, having an empty bpf_struct_ops_desc_init() for the
not CONFIG_BPF_JIT case, is it enough?
It is enough. However, it also leaves dead code.
Anyway, I just removed these conditions as you said.
+struct bpf_struct_ops_desc;
+
+const struct bpf_struct_ops_desc *
+btf_get_struct_ops(struct btf *btf, u32 *ret_cnt);
+
+#endif /* CONFIG_BPF_JIT */
+
#endif
