Message ID | 20210220034959.27006-3-iii@linux.ibm.com (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | BPF |
Headers | show |
Series | Add BTF_KIND_FLOAT support | expand |
Context | Check | Description |
---|---|---|
netdev/cover_letter | success | Link |
netdev/fixes_present | success | Link |
netdev/patch_count | success | Link |
netdev/tree_selection | success | Clearly marked for bpf-next |
netdev/subject_prefix | success | Link |
netdev/cc_maintainers | warning | 4 maintainers not CCed: songliubraving@fb.com kpsingh@kernel.org netdev@vger.kernel.org kafai@fb.com |
netdev/source_inline | success | Was 0 now: 0 |
netdev/verify_signedoff | success | Link |
netdev/module_param | success | Was 0 now: 0 |
netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
netdev/verify_fixes | success | Link |
netdev/checkpatch | warning | WARNING: line length of 81 exceeds 80 columns |
netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
netdev/header_inline | success | Link |
netdev/stable | success | Stable not CCed |
On 2/19/21 7:49 PM, Ilya Leoshkevich wrote: > The logic follows that of BTF_KIND_INT most of the time. Sanitization > replaces BTF_KIND_FLOATs with BTF_KIND_CONSTs pointing to > equally-sized BTF_KIND_ARRAYs on older kernels. > > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > --- > tools/lib/bpf/btf.c | 44 ++++++++++++++++++++++++++++++ > tools/lib/bpf/btf.h | 8 ++++++ > tools/lib/bpf/btf_dump.c | 4 +++ > tools/lib/bpf/libbpf.c | 48 ++++++++++++++++++++++++++++++++- > tools/lib/bpf/libbpf.map | 5 ++++ > tools/lib/bpf/libbpf_internal.h | 2 ++ > 6 files changed, 110 insertions(+), 1 deletion(-) > > diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c > index fdfff544f59a..1ebfcc687dab 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); > @@ -2400,6 +2404,42 @@ int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz) > return btf_commit_type(btf, sz); > } [...] I skipped deduplication part, Andrii can take a look later. > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > index d43cc3f29dae..b79a6a2e6faa 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"; > } > } > @@ -2384,18 +2387,22 @@ 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 t_uchar = 0; > int i, j, vlen; > + int t_uint = 0; > > for (i = 1; i <= btf__get_nr_types(btf); i++) { > t = (struct btf_type *)btf__type_by_id(btf, i); > @@ -2445,6 +2452,26 @@ 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 TYPEDEF(u8[]) */ replace FLOAT with CONST(u8[]). > + int t_array; > + __u32 size; > + > + size = t->size; > + if (!t_uchar) > + t_uchar = btf__add_int(btf, "unsigned char", 1, > + 0); > + if (!t_uint) > + t_uint = btf__add_int(btf, "unsigned int", 4, > + 0); > + t_array = btf__add_array(btf, t_uint, t_uchar, size); Checking whether t_array is valid here or not? We do not need to check t_uchar/t_uint. If they are invalid btf__add_array() will return -EINVAL. > + > + /* adding new types may have invalidated t */ > + t = (struct btf_type *)btf__type_by_id(btf, i); > + > + t->name_off = 0; > + t->info = BTF_INFO_ENC(BTF_KIND_CONST, 0, 0); > + t->type = t_array; > } > } > } > @@ -3882,6 +3909,18 @@ 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 +4100,9 @@ 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) > @@ -4940,6 +4982,8 @@ static int bpf_core_fields_are_compat(const struct btf *local_btf, > local_id = btf_array(local_type)->type; > targ_id = btf_array(targ_type)->type; > goto recur; > + case BTF_KIND_FLOAT: > + return local_type->size == targ_type->size; > default: > pr_warn("unexpected kind %d relocated, local [%d], target [%d]\n", > btf_kind(local_type), local_id, targ_id); > @@ -5122,6 +5166,8 @@ static int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id > skip_mods_and_typedefs(targ_btf, targ_type->type, &targ_id); > goto recur; > } > + case BTF_KIND_FLOAT: > + return local_type->size == targ_type->size; > default: > pr_warn("unexpected kind %s relocated, local [%d], target [%d]\n", > btf_kind_str(local_type), local_id, targ_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) >
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index fdfff544f59a..1ebfcc687dab 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); @@ -2400,6 +2404,42 @@ int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz) 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; + + 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); +} + /* * Append new data section variable information entry for current DATASEC type: * - *var_type_id* - type ID, describing type of the variable; @@ -3653,6 +3693,7 @@ 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 +3790,7 @@ 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 +4052,7 @@ 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 +4549,7 @@ 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..c3b11bcebeda 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -132,6 +132,9 @@ LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id, __u32 offset, __u32 byte_sz); +/* float construction APIs */ +LIBBPF_API int btf__add_float(struct btf *btf, const char *name, size_t byte_sz); + struct btf_dedup_opts { unsigned int dedup_table_size; bool dont_resolve_fwds; @@ -294,6 +297,11 @@ 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..b79a6a2e6faa 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"; } } @@ -2384,18 +2387,22 @@ 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 t_uchar = 0; int i, j, vlen; + int t_uint = 0; for (i = 1; i <= btf__get_nr_types(btf); i++) { t = (struct btf_type *)btf__type_by_id(btf, i); @@ -2445,6 +2452,26 @@ 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 TYPEDEF(u8[]) */ + int t_array; + __u32 size; + + size = t->size; + if (!t_uchar) + t_uchar = btf__add_int(btf, "unsigned char", 1, + 0); + if (!t_uint) + t_uint = btf__add_int(btf, "unsigned int", 4, + 0); + t_array = btf__add_array(btf, t_uint, t_uchar, size); + + /* adding new types may have invalidated t */ + t = (struct btf_type *)btf__type_by_id(btf, i); + + t->name_off = 0; + t->info = BTF_INFO_ENC(BTF_KIND_CONST, 0, 0); + t->type = t_array; } } } @@ -3882,6 +3909,18 @@ 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 +4100,9 @@ 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) @@ -4940,6 +4982,8 @@ static int bpf_core_fields_are_compat(const struct btf *local_btf, local_id = btf_array(local_type)->type; targ_id = btf_array(targ_type)->type; goto recur; + case BTF_KIND_FLOAT: + return local_type->size == targ_type->size; default: pr_warn("unexpected kind %d relocated, local [%d], target [%d]\n", btf_kind(local_type), local_id, targ_id); @@ -5122,6 +5166,8 @@ static int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id skip_mods_and_typedefs(targ_btf, targ_type->type, &targ_id); goto recur; } + case BTF_KIND_FLOAT: + return local_type->size == targ_type->size; default: pr_warn("unexpected kind %s relocated, local [%d], target [%d]\n", btf_kind_str(local_type), local_id, targ_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)
The logic follows that of BTF_KIND_INT most of the time. Sanitization replaces BTF_KIND_FLOATs with BTF_KIND_CONSTs pointing to equally-sized BTF_KIND_ARRAYs on older kernels. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> --- tools/lib/bpf/btf.c | 44 ++++++++++++++++++++++++++++++ tools/lib/bpf/btf.h | 8 ++++++ tools/lib/bpf/btf_dump.c | 4 +++ tools/lib/bpf/libbpf.c | 48 ++++++++++++++++++++++++++++++++- tools/lib/bpf/libbpf.map | 5 ++++ tools/lib/bpf/libbpf_internal.h | 2 ++ 6 files changed, 110 insertions(+), 1 deletion(-)