diff options
Diffstat (limited to 'tools/lib/bpf/btf_dump.c')
| -rw-r--r-- | tools/lib/bpf/btf_dump.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index 69e80ee5f70e..234e82334d56 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -13,6 +13,7 @@ #include <ctype.h> #include <endian.h> #include <errno.h> +#include <limits.h> #include <linux/err.h> #include <linux/btf.h> #include <linux/kernel.h> @@ -1076,6 +1077,43 @@ static void btf_dump_emit_enum_def(struct btf_dump *d, __u32 id, else btf_dump_emit_enum64_val(d, t, lvl, vlen); btf_dump_printf(d, "\n%s}", pfx(lvl)); + + /* special case enums with special sizes */ + if (t->size == 1) { + /* one-byte enums can be forced with mode(byte) attribute */ + btf_dump_printf(d, " __attribute__((mode(byte)))"); + } else if (t->size == 8 && d->ptr_sz == 8) { + /* enum can be 8-byte sized if one of the enumerator values + * doesn't fit in 32-bit integer, or by adding mode(word) + * attribute (but probably only on 64-bit architectures); do + * our best here to try to satisfy the contract without adding + * unnecessary attributes + */ + bool needs_word_mode; + + if (btf_is_enum(t)) { + /* enum can't represent 64-bit values, so we need word mode */ + needs_word_mode = true; + } else { + /* enum64 needs mode(word) if none of its values has + * non-zero upper 32-bits (which means that all values + * fit in 32-bit integers and won't cause compiler to + * bump enum to be 64-bit naturally + */ + int i; + + needs_word_mode = true; + for (i = 0; i < vlen; i++) { + if (btf_enum64(t)[i].val_hi32 != 0) { + needs_word_mode = false; + break; + } + } + } + if (needs_word_mode) + btf_dump_printf(d, " __attribute__((mode(word)))"); + } + } static void btf_dump_emit_fwd_def(struct btf_dump *d, __u32 id, |