bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support
@ 2021-02-26 20:22 Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 01/10] bpf: Add BTF_KIND_FLOAT to uapi Ilya Leoshkevich
                   ` (10 more replies)
  0 siblings, 11 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

Some BPF programs compiled on s390 fail to load, because s390
arch-specific linux headers contain float and double types.

Introduce support for such types by representing them using the new
BTF_KIND_FLOAT. This series deals with libbpf, bpftool, in-kernel BTF
parser as well as selftests and documentation.

There are also pahole and LLVM parts:

* https://github.com/iii-i/dwarves/commit/btf-kind-float-v2
* https://reviews.llvm.org/D83289

but they should go in after the libbpf part is integrated.

---

v0: https://lore.kernel.org/bpf/20210210030317.78820-1-iii@linux.ibm.com/
v0 -> v1: Per Andrii's suggestion, remove the unnecessary trailing u32.

v1: https://lore.kernel.org/bpf/20210216011216.3168-1-iii@linux.ibm.com/
v1 -> v2: John noticed that sanitization corrupts BTF, because new and
          old sizes don't match. Per Yonghong's suggestion, use a
          modifier type (which has the same size as the float type) as
          a replacement.
          Per Yonghong's suggestion, add size and alignment checks to
          the kernel BTF parser.

v2: https://lore.kernel.org/bpf/20210219022543.20893-1-iii@linux.ibm.com/
v2 -> v3: Based on Yonghong's suggestions: Use BTF_KIND_CONST instead of
          BTF_KIND_TYPEDEF and make sure that the C code generated from
          the sanitized BTF is well-formed; fix size calculation in
          tests and use NAME_TBD everywhere; limit allowed sizes to 2,
          4, 8, 12 and 16 (this should also fix m68k and nds32le
          builds).

v3: https://lore.kernel.org/bpf/20210220034959.27006-1-iii@linux.ibm.com/
v3 -> v4: More fixes for the Yonghong's findings: fix the outdated
          comment in bpf_object__sanitize_btf() and add the error
          handling there (I've decided to check uint_id and uchar_id
          too in order to simplify debugging); add bpftool output
          example; use div64_u64_rem() instead of % in order to fix the
          linker error.
          Also fix the "invalid BTF_INFO" test (new commit, #4).

v4: https://lore.kernel.org/bpf/20210222214917.83629-1-iii@linux.ibm.com/
v4 -> v5: Fixes for the Andrii's findings: Use BTF_KIND_STRUCT instead
          of BTF_KIND_TYPEDEF for sanitization; check byte_sz in
          libbpf; move btf__add_float; remove relo support; add a dedup
          test (new commit, #7).

v5: https://lore.kernel.org/bpf/20210223231459.99664-1-iii@linux.ibm.com/
v5 -> v6: Fixes for further findings by Andrii: split whitespace issue
          fix into a separate patch; add 12-byte float to "float test #1,
          well-formed".

v6: https://lore.kernel.org/bpf/20210224234535.106970-1-iii@linux.ibm.com/
v6 -> v7: John suggested to add a comment explaining why sanitization
          does not preserve the type name, as well as what effect it has
          on running the code on the older kernels.
          Yonghong has asked to add a comment explaining why we are not
          checking the alignment very precisely in the kernel.
          John suggested to add a bpf_core_field_size test (commit #9).

Based on Alexei's feedback [1] I'm proceeding with the BTF_KIND_FLOAT
approach.

[1] https://lore.kernel.org/bpf/CAADnVQKWPODWZ2RSJ5FJhfYpxkuV0cvSAL1O+FSr9oP1ercoBg@mail.gmail.com/

Ilya Leoshkevich (10):
  bpf: Add BTF_KIND_FLOAT to uapi
  libbpf: Fix whitespace in btf_add_composite() comment
  libbpf: Add BTF_KIND_FLOAT support
  tools/bpftool: Add BTF_KIND_FLOAT support
  selftests/bpf: Use the 25th bit in the "invalid BTF_INFO" test
  bpf: Add BTF_KIND_FLOAT support
  selftest/bpf: Add BTF_KIND_FLOAT tests
  selftests/bpf: Add BTF_KIND_FLOAT to the existing deduplication tests
  selftests/bpf: Add BTF_KIND_FLOAT to test_core_reloc_size
  bpf: Document BTF_KIND_FLOAT in btf.rst

 Documentation/bpf/btf.rst                     |  17 +-
 include/uapi/linux/btf.h                      |   5 +-
 kernel/bpf/btf.c                              |  83 ++++++++-
 tools/bpf/bpftool/btf.c                       |   8 +
 tools/bpf/bpftool/btf_dumper.c                |   1 +
 tools/include/uapi/linux/btf.h                |   5 +-
 tools/lib/bpf/btf.c                           |  51 ++++-
 tools/lib/bpf/btf.h                           |   6 +
 tools/lib/bpf/btf_dump.c                      |   4 +
 tools/lib/bpf/libbpf.c                        |  29 ++-
 tools/lib/bpf/libbpf.map                      |   5 +
 tools/lib/bpf/libbpf_internal.h               |   2 +
 tools/testing/selftests/bpf/btf_helpers.c     |   4 +
 tools/testing/selftests/bpf/prog_tests/btf.c  | 176 ++++++++++++++++--
 .../selftests/bpf/prog_tests/core_reloc.c     |   1 +
 .../selftests/bpf/progs/core_reloc_types.h    |   5 +
 .../bpf/progs/test_core_reloc_size.c          |   3 +
 tools/testing/selftests/bpf/test_btf.h        |   3 +
 18 files changed, 385 insertions(+), 23 deletions(-)

-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 01/10] bpf: Add BTF_KIND_FLOAT to uapi
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 02/10] libbpf: Fix whitespace in btf_add_composite() comment Ilya Leoshkevich
                   ` (9 subsequent siblings)
  10 siblings, 0 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

Add a new kind value and expand the kind bitfield.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
---
 include/uapi/linux/btf.h       | 5 +++--
 tools/include/uapi/linux/btf.h | 5 +++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/include/uapi/linux/btf.h b/include/uapi/linux/btf.h
index 5a667107ad2c..d27b1708efe9 100644
--- a/include/uapi/linux/btf.h
+++ b/include/uapi/linux/btf.h
@@ -52,7 +52,7 @@ struct btf_type {
 	};
 };
 
-#define BTF_INFO_KIND(info)	(((info) >> 24) & 0x0f)
+#define BTF_INFO_KIND(info)	(((info) >> 24) & 0x1f)
 #define BTF_INFO_VLEN(info)	((info) & 0xffff)
 #define BTF_INFO_KFLAG(info)	((info) >> 31)
 
@@ -72,7 +72,8 @@ struct btf_type {
 #define BTF_KIND_FUNC_PROTO	13	/* Function Proto	*/
 #define BTF_KIND_VAR		14	/* Variable	*/
 #define BTF_KIND_DATASEC	15	/* Section	*/
-#define BTF_KIND_MAX		BTF_KIND_DATASEC
+#define BTF_KIND_FLOAT		16	/* Floating point	*/
+#define BTF_KIND_MAX		BTF_KIND_FLOAT
 #define NR_BTF_KINDS		(BTF_KIND_MAX + 1)
 
 /* For some specific BTF_KIND, "struct btf_type" is immediately
diff --git a/tools/include/uapi/linux/btf.h b/tools/include/uapi/linux/btf.h
index 5a667107ad2c..d27b1708efe9 100644
--- a/tools/include/uapi/linux/btf.h
+++ b/tools/include/uapi/linux/btf.h
@@ -52,7 +52,7 @@ struct btf_type {
 	};
 };
 
-#define BTF_INFO_KIND(info)	(((info) >> 24) & 0x0f)
+#define BTF_INFO_KIND(info)	(((info) >> 24) & 0x1f)
 #define BTF_INFO_VLEN(info)	((info) & 0xffff)
 #define BTF_INFO_KFLAG(info)	((info) >> 31)
 
@@ -72,7 +72,8 @@ struct btf_type {
 #define BTF_KIND_FUNC_PROTO	13	/* Function Proto	*/
 #define BTF_KIND_VAR		14	/* Variable	*/
 #define BTF_KIND_DATASEC	15	/* Section	*/
-#define BTF_KIND_MAX		BTF_KIND_DATASEC
+#define BTF_KIND_FLOAT		16	/* Floating point	*/
+#define BTF_KIND_MAX		BTF_KIND_FLOAT
 #define NR_BTF_KINDS		(BTF_KIND_MAX + 1)
 
 /* For some specific BTF_KIND, "struct btf_type" is immediately
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 02/10] libbpf: Fix whitespace in btf_add_composite() comment
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 01/10] bpf: Add BTF_KIND_FLOAT to uapi Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 23:32   ` Yonghong Song
  2021-02-26 20:22 ` [PATCH v7 bpf-next 03/10] libbpf: Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (8 subsequent siblings)
  10 siblings, 1 reply; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

Remove trailing space.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 tools/lib/bpf/btf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 6058fbadbee4..313f62a78626 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -1910,7 +1910,7 @@ static int btf_add_composite(struct btf *btf, int kind, const char *name, __u32
  *   - *byte_sz* - size of the struct, in bytes;
  *
  * Struct initially has no fields in it. Fields can be added by
- * btf__add_field() right after btf__add_struct() succeeds. 
+ * btf__add_field() right after btf__add_struct() succeeds.
  *
  * Returns:
  *   - >0, type ID of newly added BTF type;
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 03/10] libbpf: Add BTF_KIND_FLOAT support
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 01/10] bpf: Add BTF_KIND_FLOAT to uapi Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 02/10] libbpf: Fix whitespace in btf_add_composite() comment Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 04/10] tools/bpftool: " Ilya Leoshkevich
                   ` (7 subsequent siblings)
  10 siblings, 0 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

The logic follows that of BTF_KIND_INT most of the time. Sanitization
replaces BTF_KIND_FLOATs with equally-sized empty BTF_KIND_STRUCTs on
older kernels, for example, the following:

    [4] FLOAT 'float' size=4

becomes the following:

    [4] STRUCT '(anon)' size=4 vlen=0

With dwarves patch [1] and this patch, the older kernels, which were
failing with the floating-point-related errors, will now start working
correctly.

[1] https://github.com/iii-i/dwarves/commit/btf-kind-float-v2

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
---
 tools/lib/bpf/btf.c             | 49 +++++++++++++++++++++++++++++++++
 tools/lib/bpf/btf.h             |  6 ++++
 tools/lib/bpf/btf_dump.c        |  4 +++
 tools/lib/bpf/libbpf.c          | 29 ++++++++++++++++++-
 tools/lib/bpf/libbpf.map        |  5 ++++
 tools/lib/bpf/libbpf_internal.h |  2 ++
 6 files changed, 94 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 313f62a78626..488464307c0f 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -292,6 +292,7 @@ static int btf_type_size(const struct btf_type *t)
 	case BTF_KIND_PTR:
 	case BTF_KIND_TYPEDEF:
 	case BTF_KIND_FUNC:
+	case BTF_KIND_FLOAT:
 		return base_size;
 	case BTF_KIND_INT:
 		return base_size + sizeof(__u32);
@@ -339,6 +340,7 @@ static int btf_bswap_type_rest(struct btf_type *t)
 	case BTF_KIND_PTR:
 	case BTF_KIND_TYPEDEF:
 	case BTF_KIND_FUNC:
+	case BTF_KIND_FLOAT:
 		return 0;
 	case BTF_KIND_INT:
 		*(__u32 *)(t + 1) = bswap_32(*(__u32 *)(t + 1));
@@ -579,6 +581,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id)
 		case BTF_KIND_UNION:
 		case BTF_KIND_ENUM:
 		case BTF_KIND_DATASEC:
+		case BTF_KIND_FLOAT:
 			size = t->size;
 			goto done;
 		case BTF_KIND_PTR:
@@ -622,6 +625,7 @@ int btf__align_of(const struct btf *btf, __u32 id)
 	switch (kind) {
 	case BTF_KIND_INT:
 	case BTF_KIND_ENUM:
+	case BTF_KIND_FLOAT:
 		return min(btf_ptr_sz(btf), (size_t)t->size);
 	case BTF_KIND_PTR:
 		return btf_ptr_sz(btf);
@@ -1783,6 +1787,47 @@ int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding
 	return btf_commit_type(btf, sz);
 }
 
+/*
+ * Append new BTF_KIND_FLOAT type with:
+ *   - *name* - non-empty, non-NULL type name;
+ *   - *sz* - size of the type, in bytes;
+ * Returns:
+ *   - >0, type ID of newly added BTF type;
+ *   - <0, on error.
+ */
+int btf__add_float(struct btf *btf, const char *name, size_t byte_sz)
+{
+	struct btf_type *t;
+	int sz, name_off;
+
+	/* non-empty name */
+	if (!name || !name[0])
+		return -EINVAL;
+
+	/* byte_sz must be one of the explicitly allowed values */
+	if (byte_sz != 2 && byte_sz != 4 && byte_sz != 8 && byte_sz != 12 &&
+	    byte_sz != 16)
+		return -EINVAL;
+
+	if (btf_ensure_modifiable(btf))
+		return -ENOMEM;
+
+	sz = sizeof(struct btf_type);
+	t = btf_add_type_mem(btf, sz);
+	if (!t)
+		return -ENOMEM;
+
+	name_off = btf__add_str(btf, name);
+	if (name_off < 0)
+		return name_off;
+
+	t->name_off = name_off;
+	t->info = btf_type_info(BTF_KIND_FLOAT, 0, 0);
+	t->size = byte_sz;
+
+	return btf_commit_type(btf, sz);
+}
+
 /* it's completely legal to append BTF types with type IDs pointing forward to
  * types that haven't been appended yet, so we only make sure that id looks
  * sane, we can't guarantee that ID will always be valid
@@ -3653,6 +3698,7 @@ static int btf_dedup_prep(struct btf_dedup *d)
 		case BTF_KIND_FWD:
 		case BTF_KIND_TYPEDEF:
 		case BTF_KIND_FUNC:
+		case BTF_KIND_FLOAT:
 			h = btf_hash_common(t);
 			break;
 		case BTF_KIND_INT:
@@ -3749,6 +3795,7 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id)
 		break;
 
 	case BTF_KIND_FWD:
+	case BTF_KIND_FLOAT:
 		h = btf_hash_common(t);
 		for_each_dedup_cand(d, hash_entry, h) {
 			cand_id = (__u32)(long)hash_entry->value;
@@ -4010,6 +4057,7 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
 			return btf_compat_enum(cand_type, canon_type);
 
 	case BTF_KIND_FWD:
+	case BTF_KIND_FLOAT:
 		return btf_equal_common(cand_type, canon_type);
 
 	case BTF_KIND_CONST:
@@ -4506,6 +4554,7 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
 	switch (btf_kind(t)) {
 	case BTF_KIND_INT:
 	case BTF_KIND_ENUM:
+	case BTF_KIND_FLOAT:
 		break;
 
 	case BTF_KIND_FWD:
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index 1237bcd1dd17..029a9cfc8c2d 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -95,6 +95,7 @@ LIBBPF_API int btf__find_str(struct btf *btf, const char *s);
 LIBBPF_API int btf__add_str(struct btf *btf, const char *s);
 
 LIBBPF_API int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding);
+LIBBPF_API int btf__add_float(struct btf *btf, const char *name, size_t byte_sz);
 LIBBPF_API int btf__add_ptr(struct btf *btf, int ref_type_id);
 LIBBPF_API int btf__add_array(struct btf *btf,
 			      int index_type_id, int elem_type_id, __u32 nr_elems);
@@ -294,6 +295,11 @@ static inline bool btf_is_datasec(const struct btf_type *t)
 	return btf_kind(t) == BTF_KIND_DATASEC;
 }
 
+static inline bool btf_is_float(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_FLOAT;
+}
+
 static inline __u8 btf_int_encoding(const struct btf_type *t)
 {
 	return BTF_INT_ENCODING(*(__u32 *)(t + 1));
diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
index 2f9d685bd522..5e957fcceee6 100644
--- a/tools/lib/bpf/btf_dump.c
+++ b/tools/lib/bpf/btf_dump.c
@@ -279,6 +279,7 @@ static int btf_dump_mark_referenced(struct btf_dump *d)
 		case BTF_KIND_INT:
 		case BTF_KIND_ENUM:
 		case BTF_KIND_FWD:
+		case BTF_KIND_FLOAT:
 			break;
 
 		case BTF_KIND_VOLATILE:
@@ -453,6 +454,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
 
 	switch (btf_kind(t)) {
 	case BTF_KIND_INT:
+	case BTF_KIND_FLOAT:
 		tstate->order_state = ORDERED;
 		return 0;
 
@@ -1133,6 +1135,7 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
 		case BTF_KIND_STRUCT:
 		case BTF_KIND_UNION:
 		case BTF_KIND_TYPEDEF:
+		case BTF_KIND_FLOAT:
 			goto done;
 		default:
 			pr_warn("unexpected type in decl chain, kind:%u, id:[%u]\n",
@@ -1247,6 +1250,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
 
 		switch (kind) {
 		case BTF_KIND_INT:
+		case BTF_KIND_FLOAT:
 			btf_dump_emit_mods(d, decls);
 			name = btf_name_of(d, t->name_off);
 			btf_dump_printf(d, "%s", name);
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index d43cc3f29dae..b017452d471f 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -178,6 +178,8 @@ enum kern_feature_id {
 	FEAT_PROG_BIND_MAP,
 	/* Kernel support for module BTFs */
 	FEAT_MODULE_BTF,
+	/* BTF_KIND_FLOAT support */
+	FEAT_BTF_FLOAT,
 	__FEAT_CNT,
 };
 
@@ -1935,6 +1937,7 @@ static const char *btf_kind_str(const struct btf_type *t)
 	case BTF_KIND_FUNC_PROTO: return "func_proto";
 	case BTF_KIND_VAR: return "var";
 	case BTF_KIND_DATASEC: return "datasec";
+	case BTF_KIND_FLOAT: return "float";
 	default: return "unknown";
 	}
 }
@@ -2384,15 +2387,17 @@ static bool btf_needs_sanitization(struct bpf_object *obj)
 {
 	bool has_func_global = kernel_supports(FEAT_BTF_GLOBAL_FUNC);
 	bool has_datasec = kernel_supports(FEAT_BTF_DATASEC);
+	bool has_float = kernel_supports(FEAT_BTF_FLOAT);
 	bool has_func = kernel_supports(FEAT_BTF_FUNC);
 
-	return !has_func || !has_datasec || !has_func_global;
+	return !has_func || !has_datasec || !has_func_global || !has_float;
 }
 
 static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf)
 {
 	bool has_func_global = kernel_supports(FEAT_BTF_GLOBAL_FUNC);
 	bool has_datasec = kernel_supports(FEAT_BTF_DATASEC);
+	bool has_float = kernel_supports(FEAT_BTF_FLOAT);
 	bool has_func = kernel_supports(FEAT_BTF_FUNC);
 	struct btf_type *t;
 	int i, j, vlen;
@@ -2445,6 +2450,13 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf)
 		} else if (!has_func_global && btf_is_func(t)) {
 			/* replace BTF_FUNC_GLOBAL with BTF_FUNC_STATIC */
 			t->info = BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0);
+		} else if (!has_float && btf_is_float(t)) {
+			/* replace FLOAT with an equally-sized empty STRUCT;
+			 * since C compilers do not accept e.g. "float" as a
+			 * valid struct name, make it anonymous
+			 */
+			t->name_off = 0;
+			t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 0);
 		}
 	}
 }
@@ -3882,6 +3894,18 @@ static int probe_kern_btf_datasec(void)
 					     strs, sizeof(strs)));
 }
 
+static int probe_kern_btf_float(void)
+{
+	static const char strs[] = "\0float";
+	__u32 types[] = {
+		/* float */
+		BTF_TYPE_FLOAT_ENC(1, 4),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
 static int probe_kern_array_mmap(void)
 {
 	struct bpf_create_map_attr attr = {
@@ -4061,6 +4085,9 @@ static struct kern_feature_desc {
 	[FEAT_MODULE_BTF] = {
 		"module BTF support", probe_module_btf,
 	},
+	[FEAT_BTF_FLOAT] = {
+		"BTF_KIND_FLOAT support", probe_kern_btf_float,
+	},
 };
 
 static bool kernel_supports(enum kern_feature_id feat_id)
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 1c0fd2dd233a..ec898f464ab9 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -350,3 +350,8 @@ LIBBPF_0.3.0 {
 		xsk_setup_xdp_prog;
 		xsk_socket__update_xskmap;
 } LIBBPF_0.2.0;
+
+LIBBPF_0.4.0 {
+	global:
+		btf__add_float;
+} LIBBPF_0.3.0;
diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
index 969d0ac592ba..343f6eb05637 100644
--- a/tools/lib/bpf/libbpf_internal.h
+++ b/tools/lib/bpf/libbpf_internal.h
@@ -31,6 +31,8 @@
 #define BTF_MEMBER_ENC(name, type, bits_offset) (name), (type), (bits_offset)
 #define BTF_PARAM_ENC(name, type) (name), (type)
 #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size)
+#define BTF_TYPE_FLOAT_ENC(name, sz) \
+	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz)
 
 #ifndef likely
 #define likely(x) __builtin_expect(!!(x), 1)
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 04/10] tools/bpftool: Add BTF_KIND_FLOAT support
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (2 preceding siblings ...)
  2021-02-26 20:22 ` [PATCH v7 bpf-next 03/10] libbpf: Add BTF_KIND_FLOAT support Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 05/10] selftests/bpf: Use the 25th bit in the "invalid BTF_INFO" test Ilya Leoshkevich
                   ` (6 subsequent siblings)
  10 siblings, 0 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

Only dumping support needs to be adjusted, the code structure follows
that of BTF_KIND_INT. Example plain and JSON outputs:

    [4] FLOAT 'float' size=4
    {"id":4,"kind":"FLOAT","name":"float","size":4}

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
---
 tools/bpf/bpftool/btf.c        | 8 ++++++++
 tools/bpf/bpftool/btf_dumper.c | 1 +
 2 files changed, 9 insertions(+)

diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index fe9e7b3a4b50..985610c3f193 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c
@@ -36,6 +36,7 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = {
 	[BTF_KIND_FUNC_PROTO]	= "FUNC_PROTO",
 	[BTF_KIND_VAR]		= "VAR",
 	[BTF_KIND_DATASEC]	= "DATASEC",
+	[BTF_KIND_FLOAT]	= "FLOAT",
 };
 
 struct btf_attach_table {
@@ -327,6 +328,13 @@ static int dump_btf_type(const struct btf *btf, __u32 id,
 			jsonw_end_array(w);
 		break;
 	}
+	case BTF_KIND_FLOAT: {
+		if (json_output)
+			jsonw_uint_field(w, "size", t->size);
+		else
+			printf(" size=%u", t->size);
+		break;
+	}
 	default:
 		break;
 	}
diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c
index 0e9310727281..7ca54d046362 100644
--- a/tools/bpf/bpftool/btf_dumper.c
+++ b/tools/bpf/bpftool/btf_dumper.c
@@ -596,6 +596,7 @@ static int __btf_dumper_type_only(const struct btf *btf, __u32 type_id,
 	switch (BTF_INFO_KIND(t->info)) {
 	case BTF_KIND_INT:
 	case BTF_KIND_TYPEDEF:
+	case BTF_KIND_FLOAT:
 		BTF_PRINT_ARG("%s ", btf__name_by_offset(btf, t->name_off));
 		break;
 	case BTF_KIND_STRUCT:
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 05/10] selftests/bpf: Use the 25th bit in the "invalid BTF_INFO" test
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (3 preceding siblings ...)
  2021-02-26 20:22 ` [PATCH v7 bpf-next 04/10] tools/bpftool: " Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 06/10] bpf: Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (5 subsequent siblings)
  10 siblings, 0 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

The bit being checked by this test is no longer reserved after
introducing BTF_KIND_FLOAT, so use the next one instead.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
---
 tools/testing/selftests/bpf/prog_tests/btf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c
index 6a7ee7420701..c29406736138 100644
--- a/tools/testing/selftests/bpf/prog_tests/btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf.c
@@ -1903,7 +1903,7 @@ static struct btf_raw_test raw_tests[] = {
 	.raw_types = {
 		/* int */				/* [1] */
 		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),
-		BTF_TYPE_ENC(0, 0x10000000, 4),
+		BTF_TYPE_ENC(0, 0x20000000, 4),
 		BTF_END_RAW,
 	},
 	.str_sec = "",
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 06/10] bpf: Add BTF_KIND_FLOAT support
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (4 preceding siblings ...)
  2021-02-26 20:22 ` [PATCH v7 bpf-next 05/10] selftests/bpf: Use the 25th bit in the "invalid BTF_INFO" test Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 23:33   ` Yonghong Song
  2021-02-26 20:22 ` [PATCH v7 bpf-next 07/10] selftest/bpf: Add BTF_KIND_FLOAT tests Ilya Leoshkevich
                   ` (4 subsequent siblings)
  10 siblings, 1 reply; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

On the kernel side, introduce a new btf_kind_operations. It is
similar to that of BTF_KIND_INT, however, it does not need to
handle encodings and bit offsets. Do not implement printing, since
the kernel does not know how to format floating-point values.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 kernel/bpf/btf.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 81 insertions(+), 2 deletions(-)

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 2efeb5f4b343..14687eea4e30 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -173,7 +173,7 @@
 #define BITS_ROUNDUP_BYTES(bits) \
 	(BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits))
 
-#define BTF_INFO_MASK 0x8f00ffff
+#define BTF_INFO_MASK 0x9f00ffff
 #define BTF_INT_MASK 0x0fffffff
 #define BTF_TYPE_ID_VALID(type_id) ((type_id) <= BTF_MAX_TYPE)
 #define BTF_STR_OFFSET_VALID(name_off) ((name_off) <= BTF_MAX_NAME_OFFSET)
@@ -280,6 +280,7 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = {
 	[BTF_KIND_FUNC_PROTO]	= "FUNC_PROTO",
 	[BTF_KIND_VAR]		= "VAR",
 	[BTF_KIND_DATASEC]	= "DATASEC",
+	[BTF_KIND_FLOAT]	= "FLOAT",
 };
 
 static const char *btf_type_str(const struct btf_type *t)
@@ -574,6 +575,7 @@ static bool btf_type_has_size(const struct btf_type *t)
 	case BTF_KIND_UNION:
 	case BTF_KIND_ENUM:
 	case BTF_KIND_DATASEC:
+	case BTF_KIND_FLOAT:
 		return true;
 	}
 
@@ -1704,6 +1706,7 @@ __btf_resolve_size(const struct btf *btf, const struct btf_type *type,
 		case BTF_KIND_STRUCT:
 		case BTF_KIND_UNION:
 		case BTF_KIND_ENUM:
+		case BTF_KIND_FLOAT:
 			size = type->size;
 			goto resolved;
 
@@ -1849,7 +1852,7 @@ static int btf_df_check_kflag_member(struct btf_verifier_env *env,
 	return -EINVAL;
 }
 
-/* Used for ptr, array and struct/union type members.
+/* Used for ptr, array struct/union and float type members.
  * int, enum and modifier types have their specific callback functions.
  */
 static int btf_generic_check_kflag_member(struct btf_verifier_env *env,
@@ -3675,6 +3678,81 @@ static const struct btf_kind_operations datasec_ops = {
 	.show			= btf_datasec_show,
 };
 
+static s32 btf_float_check_meta(struct btf_verifier_env *env,
+				const struct btf_type *t,
+				u32 meta_left)
+{
+	if (btf_type_vlen(t)) {
+		btf_verifier_log_type(env, t, "vlen != 0");
+		return -EINVAL;
+	}
+
+	if (btf_type_kflag(t)) {
+		btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
+		return -EINVAL;
+	}
+
+	if (t->size != 2 && t->size != 4 && t->size != 8 && t->size != 12 &&
+	    t->size != 16) {
+		btf_verifier_log_type(env, t, "Invalid type_size");
+		return -EINVAL;
+	}
+
+	btf_verifier_log_type(env, t, NULL);
+
+	return 0;
+}
+
+static int btf_float_check_member(struct btf_verifier_env *env,
+				  const struct btf_type *struct_type,
+				  const struct btf_member *member,
+				  const struct btf_type *member_type)
+{
+	u64 start_offset_bytes;
+	u64 end_offset_bytes;
+	u64 misalign_bits;
+	u64 align_bytes;
+	u64 align_bits;
+
+	/* Different architectures have different alignment requirements, so
+	 * here we check only for the reasonable minimum. This way we ensure
+	 * that types after CO-RE can pass the kernel BTF verifier.
+	 */
+	align_bytes = min_t(u64, sizeof(void *), member_type->size);
+	align_bits = align_bytes * BITS_PER_BYTE;
+	div64_u64_rem(member->offset, align_bits, &misalign_bits);
+	if (misalign_bits) {
+		btf_verifier_log_member(env, struct_type, member,
+					"Member is not properly aligned");
+		return -EINVAL;
+	}
+
+	start_offset_bytes = member->offset / BITS_PER_BYTE;
+	end_offset_bytes = start_offset_bytes + member_type->size;
+	if (end_offset_bytes > struct_type->size) {
+		btf_verifier_log_member(env, struct_type, member,
+					"Member exceeds struct_size");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void btf_float_log(struct btf_verifier_env *env,
+			  const struct btf_type *t)
+{
+	btf_verifier_log(env, "size=%u", t->size);
+}
+
+static const struct btf_kind_operations float_ops = {
+	.check_meta = btf_float_check_meta,
+	.resolve = btf_df_resolve,
+	.check_member = btf_float_check_member,
+	.check_kflag_member = btf_generic_check_kflag_member,
+	.log_details = btf_float_log,
+	.show = btf_df_show,
+};
+
 static int btf_func_proto_check(struct btf_verifier_env *env,
 				const struct btf_type *t)
 {
@@ -3808,6 +3886,7 @@ static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = {
 	[BTF_KIND_FUNC_PROTO] = &func_proto_ops,
 	[BTF_KIND_VAR] = &var_ops,
 	[BTF_KIND_DATASEC] = &datasec_ops,
+	[BTF_KIND_FLOAT] = &float_ops,
 };
 
 static s32 btf_check_meta(struct btf_verifier_env *env,
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 07/10] selftest/bpf: Add BTF_KIND_FLOAT tests
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (5 preceding siblings ...)
  2021-02-26 20:22 ` [PATCH v7 bpf-next 06/10] bpf: Add BTF_KIND_FLOAT support Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 08/10] selftests/bpf: Add BTF_KIND_FLOAT to the existing deduplication tests Ilya Leoshkevich
                   ` (3 subsequent siblings)
  10 siblings, 0 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

Test the good variants as well as the potential malformed ones.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
---
 tools/testing/selftests/bpf/btf_helpers.c    |   4 +
 tools/testing/selftests/bpf/prog_tests/btf.c | 131 +++++++++++++++++++
 tools/testing/selftests/bpf/test_btf.h       |   3 +
 3 files changed, 138 insertions(+)

diff --git a/tools/testing/selftests/bpf/btf_helpers.c b/tools/testing/selftests/bpf/btf_helpers.c
index 48f90490f922..b692e6ead9b5 100644
--- a/tools/testing/selftests/bpf/btf_helpers.c
+++ b/tools/testing/selftests/bpf/btf_helpers.c
@@ -23,6 +23,7 @@ static const char * const btf_kind_str_mapping[] = {
 	[BTF_KIND_FUNC_PROTO]	= "FUNC_PROTO",
 	[BTF_KIND_VAR]		= "VAR",
 	[BTF_KIND_DATASEC]	= "DATASEC",
+	[BTF_KIND_FLOAT]	= "FLOAT",
 };
 
 static const char *btf_kind_str(__u16 kind)
@@ -173,6 +174,9 @@ int fprintf_btf_type_raw(FILE *out, const struct btf *btf, __u32 id)
 		}
 		break;
 	}
+	case BTF_KIND_FLOAT:
+		fprintf(out, " size=%u", t->size);
+		break;
 	default:
 		break;
 	}
diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c
index c29406736138..11d98d3cf949 100644
--- a/tools/testing/selftests/bpf/prog_tests/btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf.c
@@ -3531,6 +3531,136 @@ static struct btf_raw_test raw_tests[] = {
 	.max_entries = 1,
 },
 
+{
+	.descr = "float test #1, well-formed",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+								/* [1] */
+		BTF_TYPE_FLOAT_ENC(NAME_TBD, 2),		/* [2] */
+		BTF_TYPE_FLOAT_ENC(NAME_TBD, 4),		/* [3] */
+		BTF_TYPE_FLOAT_ENC(NAME_TBD, 8),		/* [4] */
+		BTF_TYPE_FLOAT_ENC(NAME_TBD, 12),		/* [5] */
+		BTF_TYPE_FLOAT_ENC(NAME_TBD, 16),		/* [6] */
+		BTF_STRUCT_ENC(NAME_TBD, 5, 48),		/* [7] */
+		BTF_MEMBER_ENC(NAME_TBD, 2, 0),
+		BTF_MEMBER_ENC(NAME_TBD, 3, 32),
+		BTF_MEMBER_ENC(NAME_TBD, 4, 64),
+		BTF_MEMBER_ENC(NAME_TBD, 5, 128),
+		BTF_MEMBER_ENC(NAME_TBD, 6, 256),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0int\0_Float16\0float\0double\0_Float80\0long_double"
+		    "\0floats\0a\0b\0c\0d\0e"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "float_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 48,
+	.key_type_id = 1,
+	.value_type_id = 7,
+	.max_entries = 1,
+},
+{
+	.descr = "float test #2, invalid vlen",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+								/* [1] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 1), 4),
+								/* [2] */
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0int\0float"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "float_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 2,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "vlen != 0",
+},
+{
+	.descr = "float test #3, invalid kind_flag",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+								/* [1] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FLOAT, 1, 0), 4),
+								/* [2] */
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0int\0float"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "float_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 2,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid btf_info kind_flag",
+},
+{
+	.descr = "float test #4, member does not fit",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+								/* [1] */
+		BTF_TYPE_FLOAT_ENC(NAME_TBD, 4),		/* [2] */
+		BTF_STRUCT_ENC(NAME_TBD, 1, 2),			/* [3] */
+		BTF_MEMBER_ENC(NAME_TBD, 2, 0),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0int\0float\0floats\0x"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "float_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 3,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Member exceeds struct_size",
+},
+{
+	.descr = "float test #5, member is not properly aligned",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+								/* [1] */
+		BTF_TYPE_FLOAT_ENC(NAME_TBD, 4),		/* [2] */
+		BTF_STRUCT_ENC(NAME_TBD, 1, 8),			/* [3] */
+		BTF_MEMBER_ENC(NAME_TBD, 2, 8),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0int\0float\0floats\0x"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "float_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 3,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Member is not properly aligned",
+},
+{
+	.descr = "float test #6, invalid size",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4),
+								/* [1] */
+		BTF_TYPE_FLOAT_ENC(NAME_TBD, 6),		/* [2] */
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0int\0float"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "float_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 6,
+	.key_type_id = 1,
+	.value_type_id = 2,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid type_size",
+},
+
 }; /* struct btf_raw_test raw_tests[] */
 
 static const char *get_next_str(const char *start, const char *end)
@@ -6630,6 +6760,7 @@ static int btf_type_size(const struct btf_type *t)
 	case BTF_KIND_PTR:
 	case BTF_KIND_TYPEDEF:
 	case BTF_KIND_FUNC:
+	case BTF_KIND_FLOAT:
 		return base_size;
 	case BTF_KIND_INT:
 		return base_size + sizeof(__u32);
diff --git a/tools/testing/selftests/bpf/test_btf.h b/tools/testing/selftests/bpf/test_btf.h
index 2023725f1962..e2394eea4b7f 100644
--- a/tools/testing/selftests/bpf/test_btf.h
+++ b/tools/testing/selftests/bpf/test_btf.h
@@ -66,4 +66,7 @@
 #define BTF_FUNC_ENC(name, func_proto) \
 	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), func_proto)
 
+#define BTF_TYPE_FLOAT_ENC(name, sz) \
+	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz)
+
 #endif /* _TEST_BTF_H */
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 08/10] selftests/bpf: Add BTF_KIND_FLOAT to the existing deduplication tests
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (6 preceding siblings ...)
  2021-02-26 20:22 ` [PATCH v7 bpf-next 07/10] selftest/bpf: Add BTF_KIND_FLOAT tests Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 09/10] selftests/bpf: Add BTF_KIND_FLOAT to test_core_reloc_size Ilya Leoshkevich
                   ` (2 subsequent siblings)
  10 siblings, 0 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

Check that floats don't interfere with struct deduplication, that they
are not merged with another kinds and that floats of different sizes are
not merged with each other.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
---
 tools/testing/selftests/bpf/prog_tests/btf.c | 43 ++++++++++++++------
 1 file changed, 31 insertions(+), 12 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c
index 11d98d3cf949..0457ae32b270 100644
--- a/tools/testing/selftests/bpf/prog_tests/btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf.c
@@ -6411,11 +6411,12 @@ const struct btf_dedup_test dedup_tests[] = {
 			/* int[16] */
 			BTF_TYPE_ARRAY_ENC(1, 1, 16),					/* [2] */
 			/* struct s { */
-			BTF_STRUCT_ENC(NAME_NTH(2), 4, 84),				/* [3] */
+			BTF_STRUCT_ENC(NAME_NTH(2), 5, 88),				/* [3] */
 				BTF_MEMBER_ENC(NAME_NTH(3), 4, 0),	/* struct s *next;	*/
 				BTF_MEMBER_ENC(NAME_NTH(4), 5, 64),	/* const int *a;	*/
 				BTF_MEMBER_ENC(NAME_NTH(5), 2, 128),	/* int b[16];		*/
 				BTF_MEMBER_ENC(NAME_NTH(6), 1, 640),	/* int c;		*/
+				BTF_MEMBER_ENC(NAME_NTH(8), 13, 672),	/* float d;		*/
 			/* ptr -> [3] struct s */
 			BTF_PTR_ENC(3),							/* [4] */
 			/* ptr -> [6] const int */
@@ -6426,39 +6427,43 @@ const struct btf_dedup_test dedup_tests[] = {
 			/* full copy of the above */
 			BTF_TYPE_INT_ENC(NAME_NTH(1), BTF_INT_SIGNED, 0, 32, 4),	/* [7] */
 			BTF_TYPE_ARRAY_ENC(7, 7, 16),					/* [8] */
-			BTF_STRUCT_ENC(NAME_NTH(2), 4, 84),				/* [9] */
+			BTF_STRUCT_ENC(NAME_NTH(2), 5, 88),				/* [9] */
 				BTF_MEMBER_ENC(NAME_NTH(3), 10, 0),
 				BTF_MEMBER_ENC(NAME_NTH(4), 11, 64),
 				BTF_MEMBER_ENC(NAME_NTH(5), 8, 128),
 				BTF_MEMBER_ENC(NAME_NTH(6), 7, 640),
+				BTF_MEMBER_ENC(NAME_NTH(8), 13, 672),
 			BTF_PTR_ENC(9),							/* [10] */
 			BTF_PTR_ENC(12),						/* [11] */
 			BTF_CONST_ENC(7),						/* [12] */
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(7), 4),				/* [13] */
 			BTF_END_RAW,
 		},
-		BTF_STR_SEC("\0int\0s\0next\0a\0b\0c\0"),
+		BTF_STR_SEC("\0int\0s\0next\0a\0b\0c\0float\0d"),
 	},
 	.expect = {
 		.raw_types = {
 			/* int */
-			BTF_TYPE_INT_ENC(NAME_NTH(4), BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+			BTF_TYPE_INT_ENC(NAME_NTH(5), BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
 			/* int[16] */
 			BTF_TYPE_ARRAY_ENC(1, 1, 16),					/* [2] */
 			/* struct s { */
-			BTF_STRUCT_ENC(NAME_NTH(6), 4, 84),				/* [3] */
-				BTF_MEMBER_ENC(NAME_NTH(5), 4, 0),	/* struct s *next;	*/
+			BTF_STRUCT_ENC(NAME_NTH(8), 5, 88),				/* [3] */
+				BTF_MEMBER_ENC(NAME_NTH(7), 4, 0),	/* struct s *next;	*/
 				BTF_MEMBER_ENC(NAME_NTH(1), 5, 64),	/* const int *a;	*/
 				BTF_MEMBER_ENC(NAME_NTH(2), 2, 128),	/* int b[16];		*/
 				BTF_MEMBER_ENC(NAME_NTH(3), 1, 640),	/* int c;		*/
+				BTF_MEMBER_ENC(NAME_NTH(4), 7, 672),	/* float d;		*/
 			/* ptr -> [3] struct s */
 			BTF_PTR_ENC(3),							/* [4] */
 			/* ptr -> [6] const int */
 			BTF_PTR_ENC(6),							/* [5] */
 			/* const -> [1] int */
 			BTF_CONST_ENC(1),						/* [6] */
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(7), 4),				/* [7] */
 			BTF_END_RAW,
 		},
-		BTF_STR_SEC("\0a\0b\0c\0int\0next\0s"),
+		BTF_STR_SEC("\0a\0b\0c\0d\0int\0float\0next\0s"),
 	},
 	.opts = {
 		.dont_resolve_fwds = false,
@@ -6579,9 +6584,10 @@ const struct btf_dedup_test dedup_tests[] = {
 				BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 1),
 				BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 8),
 			BTF_FUNC_ENC(NAME_TBD, 12),					/* [13] func */
+			BTF_TYPE_FLOAT_ENC(NAME_TBD, 2),				/* [14] float */
 			BTF_END_RAW,
 		},
-		BTF_STR_SEC("\0A\0B\0C\0D\0E\0F\0G\0H\0I\0J\0K\0L\0M"),
+		BTF_STR_SEC("\0A\0B\0C\0D\0E\0F\0G\0H\0I\0J\0K\0L\0M\0N"),
 	},
 	.expect = {
 		.raw_types = {
@@ -6604,16 +6610,17 @@ const struct btf_dedup_test dedup_tests[] = {
 				BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 1),
 				BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 8),
 			BTF_FUNC_ENC(NAME_TBD, 12),					/* [13] func */
+			BTF_TYPE_FLOAT_ENC(NAME_TBD, 2),				/* [14] float */
 			BTF_END_RAW,
 		},
-		BTF_STR_SEC("\0A\0B\0C\0D\0E\0F\0G\0H\0I\0J\0K\0L\0M"),
+		BTF_STR_SEC("\0A\0B\0C\0D\0E\0F\0G\0H\0I\0J\0K\0L\0M\0N"),
 	},
 	.opts = {
 		.dont_resolve_fwds = false,
 	},
 },
 {
-	.descr = "dedup: no int duplicates",
+	.descr = "dedup: no int/float duplicates",
 	.input = {
 		.raw_types = {
 			BTF_TYPE_INT_ENC(NAME_NTH(1), BTF_INT_SIGNED, 0, 32, 8),
@@ -6628,9 +6635,15 @@ const struct btf_dedup_test dedup_tests[] = {
 			BTF_TYPE_INT_ENC(NAME_NTH(1), BTF_INT_SIGNED, 0, 27, 8),
 			/* different byte size */
 			BTF_TYPE_INT_ENC(NAME_NTH(1), BTF_INT_SIGNED, 0, 32, 4),
+			/* all allowed sizes */
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 2),
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 4),
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 8),
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 12),
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 16),
 			BTF_END_RAW,
 		},
-		BTF_STR_SEC("\0int\0some other int"),
+		BTF_STR_SEC("\0int\0some other int\0float"),
 	},
 	.expect = {
 		.raw_types = {
@@ -6646,9 +6659,15 @@ const struct btf_dedup_test dedup_tests[] = {
 			BTF_TYPE_INT_ENC(NAME_NTH(1), BTF_INT_SIGNED, 0, 27, 8),
 			/* different byte size */
 			BTF_TYPE_INT_ENC(NAME_NTH(1), BTF_INT_SIGNED, 0, 32, 4),
+			/* all allowed sizes */
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 2),
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 4),
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 8),
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 12),
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(3), 16),
 			BTF_END_RAW,
 		},
-		BTF_STR_SEC("\0int\0some other int"),
+		BTF_STR_SEC("\0int\0some other int\0float"),
 	},
 	.opts = {
 		.dont_resolve_fwds = false,
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 09/10] selftests/bpf: Add BTF_KIND_FLOAT to test_core_reloc_size
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (7 preceding siblings ...)
  2021-02-26 20:22 ` [PATCH v7 bpf-next 08/10] selftests/bpf: Add BTF_KIND_FLOAT to the existing deduplication tests Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-02-26 20:22 ` [PATCH v7 bpf-next 10/10] bpf: Document BTF_KIND_FLOAT in btf.rst Ilya Leoshkevich
  2021-03-05  2:36 ` [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Alexei Starovoitov
  10 siblings, 0 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

Verify that bpf_core_field_size() is working correctly with floats.

Suggested-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 tools/testing/selftests/bpf/prog_tests/core_reloc.c      | 1 +
 tools/testing/selftests/bpf/progs/core_reloc_types.h     | 5 +++++
 tools/testing/selftests/bpf/progs/test_core_reloc_size.c | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c
index 06eb956ff7bb..d94dcead72e6 100644
--- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c
+++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c
@@ -266,6 +266,7 @@ static int duration = 0;
 		.arr_elem_sz = sizeof(((type *)0)->arr_field[0]),	\
 		.ptr_sz = 8, /* always 8-byte pointer for BPF */	\
 		.enum_sz = sizeof(((type *)0)->enum_field),		\
+		.float_sz = sizeof(((type *)0)->float_field),		\
 	}
 
 #define SIZE_CASE(name) {						\
diff --git a/tools/testing/selftests/bpf/progs/core_reloc_types.h b/tools/testing/selftests/bpf/progs/core_reloc_types.h
index 9a2850850121..3a2149c5863c 100644
--- a/tools/testing/selftests/bpf/progs/core_reloc_types.h
+++ b/tools/testing/selftests/bpf/progs/core_reloc_types.h
@@ -807,6 +807,7 @@ struct core_reloc_size_output {
 	int arr_elem_sz;
 	int ptr_sz;
 	int enum_sz;
+	int float_sz;
 };
 
 struct core_reloc_size {
@@ -816,6 +817,7 @@ struct core_reloc_size {
 	int arr_field[4];
 	void *ptr_field;
 	enum { VALUE = 123 } enum_field;
+	float float_field;
 };
 
 struct core_reloc_size___diff_sz {
@@ -825,6 +827,7 @@ struct core_reloc_size___diff_sz {
 	char arr_field[10];
 	void *ptr_field;
 	enum { OTHER_VALUE = 0xFFFFFFFFFFFFFFFF } enum_field;
+	float float_field;
 };
 
 /* Error case of two candidates with the fields (int_field) at the same
@@ -839,6 +842,7 @@ struct core_reloc_size___err_ambiguous1 {
 	int arr_field[4];
 	void *ptr_field;
 	enum { VALUE___1 = 123 } enum_field;
+	float float_field;
 };
 
 struct core_reloc_size___err_ambiguous2 {
@@ -850,6 +854,7 @@ struct core_reloc_size___err_ambiguous2 {
 	int arr_field[4];
 	void *ptr_field;
 	enum { VALUE___2 = 123 } enum_field;
+	float float_field;
 };
 
 /*
diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_size.c b/tools/testing/selftests/bpf/progs/test_core_reloc_size.c
index d7fb6cfc7891..7b2d576aeea1 100644
--- a/tools/testing/selftests/bpf/progs/test_core_reloc_size.c
+++ b/tools/testing/selftests/bpf/progs/test_core_reloc_size.c
@@ -21,6 +21,7 @@ struct core_reloc_size_output {
 	int arr_elem_sz;
 	int ptr_sz;
 	int enum_sz;
+	int float_sz;
 };
 
 struct core_reloc_size {
@@ -30,6 +31,7 @@ struct core_reloc_size {
 	int arr_field[4];
 	void *ptr_field;
 	enum { VALUE = 123 } enum_field;
+	float float_field;
 };
 
 SEC("raw_tracepoint/sys_enter")
@@ -45,6 +47,7 @@ int test_core_size(void *ctx)
 	out->arr_elem_sz = bpf_core_field_size(in->arr_field[0]);
 	out->ptr_sz = bpf_core_field_size(in->ptr_field);
 	out->enum_sz = bpf_core_field_size(in->enum_field);
+	out->float_sz = bpf_core_field_size(in->float_field);
 
 	return 0;
 }
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH v7 bpf-next 10/10] bpf: Document BTF_KIND_FLOAT in btf.rst
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (8 preceding siblings ...)
  2021-02-26 20:22 ` [PATCH v7 bpf-next 09/10] selftests/bpf: Add BTF_KIND_FLOAT to test_core_reloc_size Ilya Leoshkevich
@ 2021-02-26 20:22 ` Ilya Leoshkevich
  2021-03-05  2:36 ` [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Alexei Starovoitov
  10 siblings, 0 replies; 14+ messages in thread
From: Ilya Leoshkevich @ 2021-02-26 20:22 UTC (permalink / raw)
  To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich

Also document the expansion of the kind bitfield.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
---
 Documentation/bpf/btf.rst | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/Documentation/bpf/btf.rst b/Documentation/bpf/btf.rst
index 44dc789de2b4..846354cd2d69 100644
--- a/Documentation/bpf/btf.rst
+++ b/Documentation/bpf/btf.rst
@@ -84,6 +84,7 @@ sequentially and type id is assigned to each recognized type starting from id
     #define BTF_KIND_FUNC_PROTO     13      /* Function Proto       */
     #define BTF_KIND_VAR            14      /* Variable     */
     #define BTF_KIND_DATASEC        15      /* Section      */
+    #define BTF_KIND_FLOAT          16      /* Floating point       */
 
 Note that the type section encodes debug info, not just pure types.
 ``BTF_KIND_FUNC`` is not a type, and it represents a defined subprogram.
@@ -95,8 +96,8 @@ Each type contains the following common data::
         /* "info" bits arrangement
          * bits  0-15: vlen (e.g. # of struct's members)
          * bits 16-23: unused
-         * bits 24-27: kind (e.g. int, ptr, array...etc)
-         * bits 28-30: unused
+         * bits 24-28: kind (e.g. int, ptr, array...etc)
+         * bits 29-30: unused
          * bit     31: kind_flag, currently used by
          *             struct, union and fwd
          */
@@ -452,6 +453,18 @@ map definition.
   * ``offset``: the in-section offset of the variable
   * ``size``: the size of the variable in bytes
 
+2.2.16 BTF_KIND_FLOAT
+~~~~~~~~~~~~~~~~~~~~~
+
+``struct btf_type`` encoding requirement:
+ * ``name_off``: any valid offset
+ * ``info.kind_flag``: 0
+ * ``info.kind``: BTF_KIND_FLOAT
+ * ``info.vlen``: 0
+ * ``size``: the size of the float type in bytes: 2, 4, 8, 12 or 16.
+
+No additional type data follow ``btf_type``.
+
 3. BTF Kernel API
 *****************
 
-- 
2.29.2


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH v7 bpf-next 02/10] libbpf: Fix whitespace in btf_add_composite() comment
  2021-02-26 20:22 ` [PATCH v7 bpf-next 02/10] libbpf: Fix whitespace in btf_add_composite() comment Ilya Leoshkevich
@ 2021-02-26 23:32   ` Yonghong Song
  0 siblings, 0 replies; 14+ messages in thread
From: Yonghong Song @ 2021-02-26 23:32 UTC (permalink / raw)
  To: Ilya Leoshkevich, Alexei Starovoitov, Daniel Borkmann,
	Andrii Nakryiko, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik



On 2/26/21 12:22 PM, Ilya Leoshkevich wrote:
> Remove trailing space.
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>

Acked-by: Yonghong Song <yhs@fb.com>

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH v7 bpf-next 06/10] bpf: Add BTF_KIND_FLOAT support
  2021-02-26 20:22 ` [PATCH v7 bpf-next 06/10] bpf: Add BTF_KIND_FLOAT support Ilya Leoshkevich
@ 2021-02-26 23:33   ` Yonghong Song
  0 siblings, 0 replies; 14+ messages in thread
From: Yonghong Song @ 2021-02-26 23:33 UTC (permalink / raw)
  To: Ilya Leoshkevich, Alexei Starovoitov, Daniel Borkmann,
	Andrii Nakryiko, Arnaldo Carvalho de Melo, John Fastabend
  Cc: bpf, Heiko Carstens, Vasily Gorbik



On 2/26/21 12:22 PM, Ilya Leoshkevich wrote:
> On the kernel side, introduce a new btf_kind_operations. It is
> similar to that of BTF_KIND_INT, however, it does not need to
> handle encodings and bit offsets. Do not implement printing, since
> the kernel does not know how to format floating-point values.
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>

Acked-by: Yonghong Song <yhs@fb.com>

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support
  2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
                   ` (9 preceding siblings ...)
  2021-02-26 20:22 ` [PATCH v7 bpf-next 10/10] bpf: Document BTF_KIND_FLOAT in btf.rst Ilya Leoshkevich
@ 2021-03-05  2:36 ` Alexei Starovoitov
  10 siblings, 0 replies; 14+ messages in thread
From: Alexei Starovoitov @ 2021-03-05  2:36 UTC (permalink / raw)
  To: Ilya Leoshkevich
  Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
	Yonghong Song, Arnaldo Carvalho de Melo, John Fastabend, bpf,
	Heiko Carstens, Vasily Gorbik

On Fri, Feb 26, 2021 at 12:23 PM Ilya Leoshkevich <iii@linux.ibm.com> wrote:
>
> Some BPF programs compiled on s390 fail to load, because s390
> arch-specific linux headers contain float and double types.
>
> Introduce support for such types by representing them using the new
> BTF_KIND_FLOAT. This series deals with libbpf, bpftool, in-kernel BTF
> parser as well as selftests and documentation.
>
> There are also pahole and LLVM parts:
>
> * https://github.com/iii-i/dwarves/commit/btf-kind-float-v2
> * https://reviews.llvm.org/D83289
...
> v6 -> v7: John suggested to add a comment explaining why sanitization
>           does not preserve the type name, as well as what effect it has
>           on running the code on the older kernels.
>           Yonghong has asked to add a comment explaining why we are not
>           checking the alignment very precisely in the kernel.
>           John suggested to add a bpf_core_field_size test (commit #9).

Applied without patch 9, since it crashes current llvm.
Please work with Yonghong to land llvm support
and resubmit the selftest along with an update to selftest/bpf/README.rst
that needs to explain which llvm commit is needed to pass the test.

Thanks!

^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2021-03-05  2:37 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-02-26 20:22 [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Ilya Leoshkevich
2021-02-26 20:22 ` [PATCH v7 bpf-next 01/10] bpf: Add BTF_KIND_FLOAT to uapi Ilya Leoshkevich
2021-02-26 20:22 ` [PATCH v7 bpf-next 02/10] libbpf: Fix whitespace in btf_add_composite() comment Ilya Leoshkevich
2021-02-26 23:32   ` Yonghong Song
2021-02-26 20:22 ` [PATCH v7 bpf-next 03/10] libbpf: Add BTF_KIND_FLOAT support Ilya Leoshkevich
2021-02-26 20:22 ` [PATCH v7 bpf-next 04/10] tools/bpftool: " Ilya Leoshkevich
2021-02-26 20:22 ` [PATCH v7 bpf-next 05/10] selftests/bpf: Use the 25th bit in the "invalid BTF_INFO" test Ilya Leoshkevich
2021-02-26 20:22 ` [PATCH v7 bpf-next 06/10] bpf: Add BTF_KIND_FLOAT support Ilya Leoshkevich
2021-02-26 23:33   ` Yonghong Song
2021-02-26 20:22 ` [PATCH v7 bpf-next 07/10] selftest/bpf: Add BTF_KIND_FLOAT tests Ilya Leoshkevich
2021-02-26 20:22 ` [PATCH v7 bpf-next 08/10] selftests/bpf: Add BTF_KIND_FLOAT to the existing deduplication tests Ilya Leoshkevich
2021-02-26 20:22 ` [PATCH v7 bpf-next 09/10] selftests/bpf: Add BTF_KIND_FLOAT to test_core_reloc_size Ilya Leoshkevich
2021-02-26 20:22 ` [PATCH v7 bpf-next 10/10] bpf: Document BTF_KIND_FLOAT in btf.rst Ilya Leoshkevich
2021-03-05  2:36 ` [PATCH v7 bpf-next 00/10] Add BTF_KIND_FLOAT support Alexei Starovoitov

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).