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-rw-r--r--tools/lib/bpf/relo_core.h53
1 files changed, 0 insertions, 53 deletions
diff --git a/tools/lib/bpf/relo_core.h b/tools/lib/bpf/relo_core.h
index 3d0b86e7f439..f410691cc4e5 100644
--- a/tools/lib/bpf/relo_core.h
+++ b/tools/lib/bpf/relo_core.h
@@ -6,59 +6,6 @@
#include <linux/bpf.h>
-/* The minimum bpf_core_relo checked by the loader
- *
- * CO-RE relocation captures the following data:
- * - insn_off - instruction offset (in bytes) within a BPF program that needs
- * its insn->imm field to be relocated with actual field info;
- * - type_id - BTF type ID of the "root" (containing) entity of a relocatable
- * type or field;
- * - access_str_off - offset into corresponding .BTF string section. String
- * interpretation depends on specific relocation kind:
- * - for field-based relocations, string encodes an accessed field using
- * a sequence of field and array indices, separated by colon (:). It's
- * conceptually very close to LLVM's getelementptr ([0]) instruction's
- * arguments for identifying offset to a field.
- * - for type-based relocations, strings is expected to be just "0";
- * - for enum value-based relocations, string contains an index of enum
- * value within its enum type;
- *
- * Example to provide a better feel.
- *
- * struct sample {
- * int a;
- * struct {
- * int b[10];
- * };
- * };
- *
- * struct sample *s = ...;
- * int x = &s->a; // encoded as "0:0" (a is field #0)
- * int y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1,
- * // b is field #0 inside anon struct, accessing elem #5)
- * int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array)
- *
- * type_id for all relocs in this example will capture BTF type id of
- * `struct sample`.
- *
- * Such relocation is emitted when using __builtin_preserve_access_index()
- * Clang built-in, passing expression that captures field address, e.g.:
- *
- * bpf_probe_read(&dst, sizeof(dst),
- * __builtin_preserve_access_index(&src->a.b.c));
- *
- * In this case Clang will emit field relocation recording necessary data to
- * be able to find offset of embedded `a.b.c` field within `src` struct.
- *
- * [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction
- */
-struct bpf_core_relo {
- __u32 insn_off;
- __u32 type_id;
- __u32 access_str_off;
- enum bpf_core_relo_kind kind;
-};
-
struct bpf_core_cand {
const struct btf *btf;
const struct btf_type *t;