diff options
| author | Yonghong Song <yhs@fb.com> | 2020-07-20 19:34:01 +0300 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-07-21 23:26:26 +0300 |
| commit | 0f12e584b241285cf60a6227f3771fa444cfcf76 (patch) | |
| tree | 2168b0dbe894b1966d86451de379cffcad31f37a /tools | |
| parent | d8dfe5bfe856c0c72b1750322dbfcad402e73373 (diff) | |
| download | linux-0f12e584b241285cf60a6227f3771fa444cfcf76.tar.xz | |
bpf: Add BTF_ID_LIST_GLOBAL in btf_ids.h
Existing BTF_ID_LIST used a local static variable
to store btf_ids. This patch provided a new macro
BTF_ID_LIST_GLOBAL to store btf_ids in a global
variable which can be shared among multiple files.
The existing BTF_ID_LIST is still retained.
Two reasons. First, BTF_ID_LIST is also used to build
btf_ids for helper arguments which typically
is an array of 5. Since typically different
helpers have different signature, it makes
little sense to share them. Second, some
current computed btf_ids are indeed local.
If later those btf_ids are shared between
different files, they can use BTF_ID_LIST_GLOBAL then.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/bpf/20200720163401.1393159-1-yhs@fb.com
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/include/linux/btf_ids.h | 10 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/resolve_btfids.c | 33 |
2 files changed, 32 insertions, 11 deletions
diff --git a/tools/include/linux/btf_ids.h b/tools/include/linux/btf_ids.h index 1cdb56950ffe..77ab45baa095 100644 --- a/tools/include/linux/btf_ids.h +++ b/tools/include/linux/btf_ids.h @@ -57,17 +57,20 @@ asm( \ * .zero 4 * */ -#define __BTF_ID_LIST(name) \ +#define __BTF_ID_LIST(name, scope) \ asm( \ ".pushsection " BTF_IDS_SECTION ",\"a\"; \n" \ -".local " #name "; \n" \ +"." #scope " " #name "; \n" \ #name ":; \n" \ ".popsection; \n"); \ #define BTF_ID_LIST(name) \ -__BTF_ID_LIST(name) \ +__BTF_ID_LIST(name, local) \ extern u32 name[]; +#define BTF_ID_LIST_GLOBAL(name) \ +__BTF_ID_LIST(name, globl) + /* * The BTF_ID_UNUSED macro defines 4 zero bytes. * It's used when we want to define 'unused' entry @@ -90,6 +93,7 @@ asm( \ #define BTF_ID_LIST(name) static u32 name[5]; #define BTF_ID(prefix, name) #define BTF_ID_UNUSED +#define BTF_ID_LIST_GLOBAL(name) u32 name[1]; #endif /* CONFIG_DEBUG_INFO_BTF */ diff --git a/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c b/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c index 22d83bba4e91..3b127cab4864 100644 --- a/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c +++ b/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c @@ -28,7 +28,17 @@ struct symbol test_symbols[] = { { "func", BTF_KIND_FUNC, -1 }, }; -BTF_ID_LIST(test_list) +BTF_ID_LIST(test_list_local) +BTF_ID_UNUSED +BTF_ID(typedef, S) +BTF_ID(typedef, T) +BTF_ID(typedef, U) +BTF_ID(struct, S) +BTF_ID(union, U) +BTF_ID(func, func) + +extern __u32 test_list_global[]; +BTF_ID_LIST_GLOBAL(test_list_global) BTF_ID_UNUSED BTF_ID(typedef, S) BTF_ID(typedef, T) @@ -94,18 +104,25 @@ static int resolve_symbols(void) int test_resolve_btfids(void) { - unsigned int i; + __u32 *test_list, *test_lists[] = { test_list_local, test_list_global }; + unsigned int i, j; int ret = 0; if (resolve_symbols()) return -1; - /* Check BTF_ID_LIST(test_list) IDs */ - for (i = 0; i < ARRAY_SIZE(test_symbols) && !ret; i++) { - ret = CHECK(test_list[i] != test_symbols[i].id, - "id_check", - "wrong ID for %s (%d != %d)\n", test_symbols[i].name, - test_list[i], test_symbols[i].id); + /* Check BTF_ID_LIST(test_list_local) and + * BTF_ID_LIST_GLOBAL(test_list_global) IDs + */ + for (j = 0; j < ARRAY_SIZE(test_lists); j++) { + test_list = test_lists[j]; + for (i = 0; i < ARRAY_SIZE(test_symbols) && !ret; i++) { + ret = CHECK(test_list[i] != test_symbols[i].id, + "id_check", + "wrong ID for %s (%d != %d)\n", + test_symbols[i].name, + test_list[i], test_symbols[i].id); + } } return ret; |