9 #include "demangle-java.h"
10 #include "demangle-rust.h"
13 #include <symbol/kallsyms.h>
17 #define EM_AARCH64 183 /* ARM 64 bit */
20 typedef Elf64_Nhdr GElf_Nhdr
;
22 #ifdef HAVE_CPLUS_DEMANGLE_SUPPORT
23 extern char *cplus_demangle(const char *, int);
25 static inline char *bfd_demangle(void __maybe_unused
*v
, const char *c
, int i
)
27 return cplus_demangle(c
, i
);
31 static inline char *bfd_demangle(void __maybe_unused
*v
,
32 const char __maybe_unused
*c
,
38 #define PACKAGE 'perf'
43 #ifndef HAVE_ELF_GETPHDRNUM_SUPPORT
44 static int elf_getphdrnum(Elf
*elf
, size_t *dst
)
49 ehdr
= gelf_getehdr(elf
, &gehdr
);
59 #ifndef HAVE_ELF_GETSHDRSTRNDX_SUPPORT
60 static int elf_getshdrstrndx(Elf
*elf __maybe_unused
, size_t *dst __maybe_unused
)
62 pr_err("%s: update your libelf to > 0.140, this one lacks elf_getshdrstrndx().\n", __func__
);
67 #ifndef NT_GNU_BUILD_ID
68 #define NT_GNU_BUILD_ID 3
72 * elf_symtab__for_each_symbol - iterate thru all the symbols
74 * @syms: struct elf_symtab instance to iterate
76 * @sym: GElf_Sym iterator
78 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
79 for (idx = 0, gelf_getsym(syms, idx, &sym);\
81 idx++, gelf_getsym(syms, idx, &sym))
83 static inline uint8_t elf_sym__type(const GElf_Sym
*sym
)
85 return GELF_ST_TYPE(sym
->st_info
);
89 #define STT_GNU_IFUNC 10
92 static inline int elf_sym__is_function(const GElf_Sym
*sym
)
94 return (elf_sym__type(sym
) == STT_FUNC
||
95 elf_sym__type(sym
) == STT_GNU_IFUNC
) &&
97 sym
->st_shndx
!= SHN_UNDEF
;
100 static inline bool elf_sym__is_object(const GElf_Sym
*sym
)
102 return elf_sym__type(sym
) == STT_OBJECT
&&
104 sym
->st_shndx
!= SHN_UNDEF
;
107 static inline int elf_sym__is_label(const GElf_Sym
*sym
)
109 return elf_sym__type(sym
) == STT_NOTYPE
&&
111 sym
->st_shndx
!= SHN_UNDEF
&&
112 sym
->st_shndx
!= SHN_ABS
;
115 static bool elf_sym__is_a(GElf_Sym
*sym
, enum map_type type
)
119 return elf_sym__is_function(sym
);
121 return elf_sym__is_object(sym
);
127 static inline const char *elf_sym__name(const GElf_Sym
*sym
,
128 const Elf_Data
*symstrs
)
130 return symstrs
->d_buf
+ sym
->st_name
;
133 static inline const char *elf_sec__name(const GElf_Shdr
*shdr
,
134 const Elf_Data
*secstrs
)
136 return secstrs
->d_buf
+ shdr
->sh_name
;
139 static inline int elf_sec__is_text(const GElf_Shdr
*shdr
,
140 const Elf_Data
*secstrs
)
142 return strstr(elf_sec__name(shdr
, secstrs
), "text") != NULL
;
145 static inline bool elf_sec__is_data(const GElf_Shdr
*shdr
,
146 const Elf_Data
*secstrs
)
148 return strstr(elf_sec__name(shdr
, secstrs
), "data") != NULL
;
151 static bool elf_sec__is_a(GElf_Shdr
*shdr
, Elf_Data
*secstrs
,
156 return elf_sec__is_text(shdr
, secstrs
);
158 return elf_sec__is_data(shdr
, secstrs
);
164 static size_t elf_addr_to_index(Elf
*elf
, GElf_Addr addr
)
170 while ((sec
= elf_nextscn(elf
, sec
)) != NULL
) {
171 gelf_getshdr(sec
, &shdr
);
173 if ((addr
>= shdr
.sh_addr
) &&
174 (addr
< (shdr
.sh_addr
+ shdr
.sh_size
)))
183 Elf_Scn
*elf_section_by_name(Elf
*elf
, GElf_Ehdr
*ep
,
184 GElf_Shdr
*shp
, const char *name
, size_t *idx
)
189 /* Elf is corrupted/truncated, avoid calling elf_strptr. */
190 if (!elf_rawdata(elf_getscn(elf
, ep
->e_shstrndx
), NULL
))
193 while ((sec
= elf_nextscn(elf
, sec
)) != NULL
) {
196 gelf_getshdr(sec
, shp
);
197 str
= elf_strptr(elf
, ep
->e_shstrndx
, shp
->sh_name
);
198 if (str
&& !strcmp(name
, str
)) {
209 static bool want_demangle(bool is_kernel_sym
)
211 return is_kernel_sym
? symbol_conf
.demangle_kernel
: symbol_conf
.demangle
;
214 static char *demangle_sym(struct dso
*dso
, int kmodule
, const char *elf_name
)
216 int demangle_flags
= verbose
> 0 ? (DMGL_PARAMS
| DMGL_ANSI
) : DMGL_NO_OPTS
;
217 char *demangled
= NULL
;
220 * We need to figure out if the object was created from C++ sources
221 * DWARF DW_compile_unit has this, but we don't always have access
224 if (!want_demangle(dso
->kernel
|| kmodule
))
227 demangled
= bfd_demangle(NULL
, elf_name
, demangle_flags
);
228 if (demangled
== NULL
)
229 demangled
= java_demangle_sym(elf_name
, JAVA_DEMANGLE_NORET
);
230 else if (rust_is_mangled(demangled
))
232 * Input to Rust demangling is the BFD-demangled
233 * name which it Rust-demangles in place.
235 rust_demangle_sym(demangled
);
240 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
241 for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
243 ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
245 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
246 for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
248 ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
251 * We need to check if we have a .dynsym, so that we can handle the
252 * .plt, synthesizing its symbols, that aren't on the symtabs (be it
253 * .dynsym or .symtab).
254 * And always look at the original dso, not at debuginfo packages, that
255 * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
257 int dso__synthesize_plt_symbols(struct dso
*dso
, struct symsrc
*ss
, struct map
*map
)
259 uint32_t nr_rel_entries
, idx
;
264 GElf_Shdr shdr_rel_plt
, shdr_dynsym
;
265 Elf_Data
*reldata
, *syms
, *symstrs
;
266 Elf_Scn
*scn_plt_rel
, *scn_symstrs
, *scn_dynsym
;
269 char sympltname
[1024];
271 int nr
= 0, symidx
, err
= 0;
279 scn_dynsym
= ss
->dynsym
;
280 shdr_dynsym
= ss
->dynshdr
;
281 dynsym_idx
= ss
->dynsym_idx
;
283 if (scn_dynsym
== NULL
)
286 scn_plt_rel
= elf_section_by_name(elf
, &ehdr
, &shdr_rel_plt
,
288 if (scn_plt_rel
== NULL
) {
289 scn_plt_rel
= elf_section_by_name(elf
, &ehdr
, &shdr_rel_plt
,
291 if (scn_plt_rel
== NULL
)
297 if (shdr_rel_plt
.sh_link
!= dynsym_idx
)
300 if (elf_section_by_name(elf
, &ehdr
, &shdr_plt
, ".plt", NULL
) == NULL
)
304 * Fetch the relocation section to find the idxes to the GOT
305 * and the symbols in the .dynsym they refer to.
307 reldata
= elf_getdata(scn_plt_rel
, NULL
);
311 syms
= elf_getdata(scn_dynsym
, NULL
);
315 scn_symstrs
= elf_getscn(elf
, shdr_dynsym
.sh_link
);
316 if (scn_symstrs
== NULL
)
319 symstrs
= elf_getdata(scn_symstrs
, NULL
);
323 if (symstrs
->d_size
== 0)
326 nr_rel_entries
= shdr_rel_plt
.sh_size
/ shdr_rel_plt
.sh_entsize
;
327 plt_offset
= shdr_plt
.sh_offset
;
329 if (shdr_rel_plt
.sh_type
== SHT_RELA
) {
330 GElf_Rela pos_mem
, *pos
;
332 elf_section__for_each_rela(reldata
, pos
, pos_mem
, idx
,
334 const char *elf_name
= NULL
;
335 char *demangled
= NULL
;
336 symidx
= GELF_R_SYM(pos
->r_info
);
337 plt_offset
+= shdr_plt
.sh_entsize
;
338 gelf_getsym(syms
, symidx
, &sym
);
340 elf_name
= elf_sym__name(&sym
, symstrs
);
341 demangled
= demangle_sym(dso
, 0, elf_name
);
342 if (demangled
!= NULL
)
343 elf_name
= demangled
;
344 snprintf(sympltname
, sizeof(sympltname
),
348 f
= symbol__new(plt_offset
, shdr_plt
.sh_entsize
,
349 STB_GLOBAL
, sympltname
);
353 symbols__insert(&dso
->symbols
[map
->type
], f
);
356 } else if (shdr_rel_plt
.sh_type
== SHT_REL
) {
357 GElf_Rel pos_mem
, *pos
;
358 elf_section__for_each_rel(reldata
, pos
, pos_mem
, idx
,
360 const char *elf_name
= NULL
;
361 char *demangled
= NULL
;
362 symidx
= GELF_R_SYM(pos
->r_info
);
363 plt_offset
+= shdr_plt
.sh_entsize
;
364 gelf_getsym(syms
, symidx
, &sym
);
366 elf_name
= elf_sym__name(&sym
, symstrs
);
367 demangled
= demangle_sym(dso
, 0, elf_name
);
368 if (demangled
!= NULL
)
369 elf_name
= demangled
;
370 snprintf(sympltname
, sizeof(sympltname
),
374 f
= symbol__new(plt_offset
, shdr_plt
.sh_entsize
,
375 STB_GLOBAL
, sympltname
);
379 symbols__insert(&dso
->symbols
[map
->type
], f
);
388 pr_debug("%s: problems reading %s PLT info.\n",
389 __func__
, dso
->long_name
);
394 * Align offset to 4 bytes as needed for note name and descriptor data.
396 #define NOTE_ALIGN(n) (((n) + 3) & -4U)
398 static int elf_read_build_id(Elf
*elf
, void *bf
, size_t size
)
408 if (size
< BUILD_ID_SIZE
)
415 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
416 pr_err("%s: cannot get elf header.\n", __func__
);
421 * Check following sections for notes:
422 * '.note.gnu.build-id'
424 * '.note' (VDSO specific)
427 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
428 ".note.gnu.build-id", NULL
);
432 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
437 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
446 data
= elf_getdata(sec
, NULL
);
451 while (ptr
< (data
->d_buf
+ data
->d_size
)) {
452 GElf_Nhdr
*nhdr
= ptr
;
453 size_t namesz
= NOTE_ALIGN(nhdr
->n_namesz
),
454 descsz
= NOTE_ALIGN(nhdr
->n_descsz
);
457 ptr
+= sizeof(*nhdr
);
460 if (nhdr
->n_type
== NT_GNU_BUILD_ID
&&
461 nhdr
->n_namesz
== sizeof("GNU")) {
462 if (memcmp(name
, "GNU", sizeof("GNU")) == 0) {
463 size_t sz
= min(size
, descsz
);
465 memset(bf
+ sz
, 0, size
- sz
);
477 int filename__read_build_id(const char *filename
, void *bf
, size_t size
)
482 if (size
< BUILD_ID_SIZE
)
485 fd
= open(filename
, O_RDONLY
);
489 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
491 pr_debug2("%s: cannot read %s ELF file.\n", __func__
, filename
);
495 err
= elf_read_build_id(elf
, bf
, size
);
504 int sysfs__read_build_id(const char *filename
, void *build_id
, size_t size
)
508 if (size
< BUILD_ID_SIZE
)
511 fd
= open(filename
, O_RDONLY
);
518 size_t namesz
, descsz
;
520 if (read(fd
, &nhdr
, sizeof(nhdr
)) != sizeof(nhdr
))
523 namesz
= NOTE_ALIGN(nhdr
.n_namesz
);
524 descsz
= NOTE_ALIGN(nhdr
.n_descsz
);
525 if (nhdr
.n_type
== NT_GNU_BUILD_ID
&&
526 nhdr
.n_namesz
== sizeof("GNU")) {
527 if (read(fd
, bf
, namesz
) != (ssize_t
)namesz
)
529 if (memcmp(bf
, "GNU", sizeof("GNU")) == 0) {
530 size_t sz
= min(descsz
, size
);
531 if (read(fd
, build_id
, sz
) == (ssize_t
)sz
) {
532 memset(build_id
+ sz
, 0, size
- sz
);
536 } else if (read(fd
, bf
, descsz
) != (ssize_t
)descsz
)
539 int n
= namesz
+ descsz
;
541 if (n
> (int)sizeof(bf
)) {
543 pr_debug("%s: truncating reading of build id in sysfs file %s: n_namesz=%u, n_descsz=%u.\n",
544 __func__
, filename
, nhdr
.n_namesz
, nhdr
.n_descsz
);
546 if (read(fd
, bf
, n
) != n
)
555 int filename__read_debuglink(const char *filename
, char *debuglink
,
566 fd
= open(filename
, O_RDONLY
);
570 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
572 pr_debug2("%s: cannot read %s ELF file.\n", __func__
, filename
);
580 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
581 pr_err("%s: cannot get elf header.\n", __func__
);
585 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
586 ".gnu_debuglink", NULL
);
590 data
= elf_getdata(sec
, NULL
);
594 /* the start of this section is a zero-terminated string */
595 strncpy(debuglink
, data
->d_buf
, size
);
607 static int dso__swap_init(struct dso
*dso
, unsigned char eidata
)
609 static unsigned int const endian
= 1;
611 dso
->needs_swap
= DSO_SWAP__NO
;
615 /* We are big endian, DSO is little endian. */
616 if (*(unsigned char const *)&endian
!= 1)
617 dso
->needs_swap
= DSO_SWAP__YES
;
621 /* We are little endian, DSO is big endian. */
622 if (*(unsigned char const *)&endian
!= 0)
623 dso
->needs_swap
= DSO_SWAP__YES
;
627 pr_err("unrecognized DSO data encoding %d\n", eidata
);
634 static int decompress_kmodule(struct dso
*dso
, const char *name
,
635 enum dso_binary_type type
)
638 char tmpbuf
[] = "/tmp/perf-kmod-XXXXXX";
641 if (type
!= DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP
&&
642 type
!= DSO_BINARY_TYPE__GUEST_KMODULE_COMP
&&
643 type
!= DSO_BINARY_TYPE__BUILD_ID_CACHE
)
646 if (type
== DSO_BINARY_TYPE__BUILD_ID_CACHE
)
647 name
= dso
->long_name
;
649 if (kmod_path__parse_ext(&m
, name
) || !m
.comp
)
652 fd
= mkstemp(tmpbuf
);
654 dso
->load_errno
= errno
;
658 if (!decompress_to_file(m
.ext
, name
, fd
)) {
659 dso
->load_errno
= DSO_LOAD_ERRNO__DECOMPRESSION_FAILURE
;
671 bool symsrc__possibly_runtime(struct symsrc
*ss
)
673 return ss
->dynsym
|| ss
->opdsec
;
676 bool symsrc__has_symtab(struct symsrc
*ss
)
678 return ss
->symtab
!= NULL
;
681 void symsrc__destroy(struct symsrc
*ss
)
688 bool __weak
elf__needs_adjust_symbols(GElf_Ehdr ehdr
)
690 return ehdr
.e_type
== ET_EXEC
|| ehdr
.e_type
== ET_REL
;
693 int symsrc__init(struct symsrc
*ss
, struct dso
*dso
, const char *name
,
694 enum dso_binary_type type
)
701 if (dso__needs_decompress(dso
)) {
702 fd
= decompress_kmodule(dso
, name
, type
);
706 fd
= open(name
, O_RDONLY
);
708 dso
->load_errno
= errno
;
713 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
715 pr_debug("%s: cannot read %s ELF file.\n", __func__
, name
);
716 dso
->load_errno
= DSO_LOAD_ERRNO__INVALID_ELF
;
720 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
721 dso
->load_errno
= DSO_LOAD_ERRNO__INVALID_ELF
;
722 pr_debug("%s: cannot get elf header.\n", __func__
);
726 if (dso__swap_init(dso
, ehdr
.e_ident
[EI_DATA
])) {
727 dso
->load_errno
= DSO_LOAD_ERRNO__INTERNAL_ERROR
;
731 /* Always reject images with a mismatched build-id: */
732 if (dso
->has_build_id
&& !symbol_conf
.ignore_vmlinux_buildid
) {
733 u8 build_id
[BUILD_ID_SIZE
];
735 if (elf_read_build_id(elf
, build_id
, BUILD_ID_SIZE
) < 0) {
736 dso
->load_errno
= DSO_LOAD_ERRNO__CANNOT_READ_BUILDID
;
740 if (!dso__build_id_equal(dso
, build_id
)) {
741 pr_debug("%s: build id mismatch for %s.\n", __func__
, name
);
742 dso
->load_errno
= DSO_LOAD_ERRNO__MISMATCHING_BUILDID
;
747 ss
->is_64_bit
= (gelf_getclass(elf
) == ELFCLASS64
);
749 ss
->symtab
= elf_section_by_name(elf
, &ehdr
, &ss
->symshdr
, ".symtab",
751 if (ss
->symshdr
.sh_type
!= SHT_SYMTAB
)
755 ss
->dynsym
= elf_section_by_name(elf
, &ehdr
, &ss
->dynshdr
, ".dynsym",
757 if (ss
->dynshdr
.sh_type
!= SHT_DYNSYM
)
761 ss
->opdsec
= elf_section_by_name(elf
, &ehdr
, &ss
->opdshdr
, ".opd",
763 if (ss
->opdshdr
.sh_type
!= SHT_PROGBITS
)
766 if (dso
->kernel
== DSO_TYPE_USER
)
767 ss
->adjust_symbols
= true;
769 ss
->adjust_symbols
= elf__needs_adjust_symbols(ehdr
);
771 ss
->name
= strdup(name
);
773 dso
->load_errno
= errno
;
792 * ref_reloc_sym_not_found - has kernel relocation symbol been found.
793 * @kmap: kernel maps and relocation reference symbol
795 * This function returns %true if we are dealing with the kernel maps and the
796 * relocation reference symbol has not yet been found. Otherwise %false is
799 static bool ref_reloc_sym_not_found(struct kmap
*kmap
)
801 return kmap
&& kmap
->ref_reloc_sym
&& kmap
->ref_reloc_sym
->name
&&
802 !kmap
->ref_reloc_sym
->unrelocated_addr
;
806 * ref_reloc - kernel relocation offset.
807 * @kmap: kernel maps and relocation reference symbol
809 * This function returns the offset of kernel addresses as determined by using
810 * the relocation reference symbol i.e. if the kernel has not been relocated
811 * then the return value is zero.
813 static u64
ref_reloc(struct kmap
*kmap
)
815 if (kmap
&& kmap
->ref_reloc_sym
&&
816 kmap
->ref_reloc_sym
->unrelocated_addr
)
817 return kmap
->ref_reloc_sym
->addr
-
818 kmap
->ref_reloc_sym
->unrelocated_addr
;
822 void __weak
arch__sym_update(struct symbol
*s __maybe_unused
,
823 GElf_Sym
*sym __maybe_unused
) { }
825 int dso__load_sym(struct dso
*dso
, struct map
*map
, struct symsrc
*syms_ss
,
826 struct symsrc
*runtime_ss
, int kmodule
)
828 struct kmap
*kmap
= dso
->kernel
? map__kmap(map
) : NULL
;
829 struct map_groups
*kmaps
= kmap
? map__kmaps(map
) : NULL
;
830 struct map
*curr_map
= map
;
831 struct dso
*curr_dso
= dso
;
832 Elf_Data
*symstrs
, *secstrs
;
839 Elf_Data
*syms
, *opddata
= NULL
;
841 Elf_Scn
*sec
, *sec_strndx
;
844 bool remap_kernel
= false, adjust_kernel_syms
= false;
849 dso
->symtab_type
= syms_ss
->type
;
850 dso
->is_64_bit
= syms_ss
->is_64_bit
;
851 dso
->rel
= syms_ss
->ehdr
.e_type
== ET_REL
;
854 * Modules may already have symbols from kallsyms, but those symbols
855 * have the wrong values for the dso maps, so remove them.
857 if (kmodule
&& syms_ss
->symtab
)
858 symbols__delete(&dso
->symbols
[map
->type
]);
860 if (!syms_ss
->symtab
) {
862 * If the vmlinux is stripped, fail so we will fall back
863 * to using kallsyms. The vmlinux runtime symbols aren't
869 syms_ss
->symtab
= syms_ss
->dynsym
;
870 syms_ss
->symshdr
= syms_ss
->dynshdr
;
874 ehdr
= syms_ss
->ehdr
;
875 sec
= syms_ss
->symtab
;
876 shdr
= syms_ss
->symshdr
;
878 if (elf_section_by_name(runtime_ss
->elf
, &runtime_ss
->ehdr
, &tshdr
,
880 dso
->text_offset
= tshdr
.sh_addr
- tshdr
.sh_offset
;
882 if (runtime_ss
->opdsec
)
883 opddata
= elf_rawdata(runtime_ss
->opdsec
, NULL
);
885 syms
= elf_getdata(sec
, NULL
);
889 sec
= elf_getscn(elf
, shdr
.sh_link
);
893 symstrs
= elf_getdata(sec
, NULL
);
897 sec_strndx
= elf_getscn(runtime_ss
->elf
, runtime_ss
->ehdr
.e_shstrndx
);
898 if (sec_strndx
== NULL
)
901 secstrs
= elf_getdata(sec_strndx
, NULL
);
905 nr_syms
= shdr
.sh_size
/ shdr
.sh_entsize
;
907 memset(&sym
, 0, sizeof(sym
));
910 * The kernel relocation symbol is needed in advance in order to adjust
911 * kernel maps correctly.
913 if (ref_reloc_sym_not_found(kmap
)) {
914 elf_symtab__for_each_symbol(syms
, nr_syms
, idx
, sym
) {
915 const char *elf_name
= elf_sym__name(&sym
, symstrs
);
917 if (strcmp(elf_name
, kmap
->ref_reloc_sym
->name
))
919 kmap
->ref_reloc_sym
->unrelocated_addr
= sym
.st_value
;
920 map
->reloc
= kmap
->ref_reloc_sym
->addr
-
921 kmap
->ref_reloc_sym
->unrelocated_addr
;
927 * Handle any relocation of vdso necessary because older kernels
928 * attempted to prelink vdso to its virtual address.
930 if (dso__is_vdso(dso
))
931 map
->reloc
= map
->start
- dso
->text_offset
;
933 dso
->adjust_symbols
= runtime_ss
->adjust_symbols
|| ref_reloc(kmap
);
935 * Initial kernel and module mappings do not map to the dso. For
936 * function mappings, flag the fixups.
938 if (map
->type
== MAP__FUNCTION
&& (dso
->kernel
|| kmodule
)) {
940 adjust_kernel_syms
= dso
->adjust_symbols
;
942 elf_symtab__for_each_symbol(syms
, nr_syms
, idx
, sym
) {
944 const char *elf_name
= elf_sym__name(&sym
, symstrs
);
945 char *demangled
= NULL
;
946 int is_label
= elf_sym__is_label(&sym
);
947 const char *section_name
;
948 bool used_opd
= false;
950 if (!is_label
&& !elf_sym__is_a(&sym
, map
->type
))
953 /* Reject ARM ELF "mapping symbols": these aren't unique and
954 * don't identify functions, so will confuse the profile
956 if (ehdr
.e_machine
== EM_ARM
|| ehdr
.e_machine
== EM_AARCH64
) {
957 if (elf_name
[0] == '$' && strchr("adtx", elf_name
[1])
958 && (elf_name
[2] == '\0' || elf_name
[2] == '.'))
962 if (runtime_ss
->opdsec
&& sym
.st_shndx
== runtime_ss
->opdidx
) {
963 u32 offset
= sym
.st_value
- syms_ss
->opdshdr
.sh_addr
;
964 u64
*opd
= opddata
->d_buf
+ offset
;
965 sym
.st_value
= DSO__SWAP(dso
, u64
, *opd
);
966 sym
.st_shndx
= elf_addr_to_index(runtime_ss
->elf
,
971 * When loading symbols in a data mapping, ABS symbols (which
972 * has a value of SHN_ABS in its st_shndx) failed at
973 * elf_getscn(). And it marks the loading as a failure so
974 * already loaded symbols cannot be fixed up.
976 * I'm not sure what should be done. Just ignore them for now.
979 if (sym
.st_shndx
== SHN_ABS
)
982 sec
= elf_getscn(runtime_ss
->elf
, sym
.st_shndx
);
986 gelf_getshdr(sec
, &shdr
);
988 if (is_label
&& !elf_sec__is_a(&shdr
, secstrs
, map
->type
))
991 section_name
= elf_sec__name(&shdr
, secstrs
);
993 /* On ARM, symbols for thumb functions have 1 added to
994 * the symbol address as a flag - remove it */
995 if ((ehdr
.e_machine
== EM_ARM
) &&
996 (map
->type
== MAP__FUNCTION
) &&
1000 if (dso
->kernel
|| kmodule
) {
1001 char dso_name
[PATH_MAX
];
1003 /* Adjust symbol to map to file offset */
1004 if (adjust_kernel_syms
)
1005 sym
.st_value
-= shdr
.sh_addr
- shdr
.sh_offset
;
1007 if (strcmp(section_name
,
1008 (curr_dso
->short_name
+
1009 dso
->short_name_len
)) == 0)
1012 if (strcmp(section_name
, ".text") == 0) {
1014 * The initial kernel mapping is based on
1015 * kallsyms and identity maps. Overwrite it to
1016 * map to the kernel dso.
1018 if (remap_kernel
&& dso
->kernel
) {
1019 remap_kernel
= false;
1020 map
->start
= shdr
.sh_addr
+
1022 map
->end
= map
->start
+ shdr
.sh_size
;
1023 map
->pgoff
= shdr
.sh_offset
;
1024 map
->map_ip
= map__map_ip
;
1025 map
->unmap_ip
= map__unmap_ip
;
1026 /* Ensure maps are correctly ordered */
1029 map_groups__remove(kmaps
, map
);
1030 map_groups__insert(kmaps
, map
);
1036 * The initial module mapping is based on
1037 * /proc/modules mapped to offset zero.
1038 * Overwrite it to map to the module dso.
1040 if (remap_kernel
&& kmodule
) {
1041 remap_kernel
= false;
1042 map
->pgoff
= shdr
.sh_offset
;
1053 snprintf(dso_name
, sizeof(dso_name
),
1054 "%s%s", dso
->short_name
, section_name
);
1056 curr_map
= map_groups__find_by_name(kmaps
, map
->type
, dso_name
);
1057 if (curr_map
== NULL
) {
1058 u64 start
= sym
.st_value
;
1061 start
+= map
->start
+ shdr
.sh_offset
;
1063 curr_dso
= dso__new(dso_name
);
1064 if (curr_dso
== NULL
)
1066 curr_dso
->kernel
= dso
->kernel
;
1067 curr_dso
->long_name
= dso
->long_name
;
1068 curr_dso
->long_name_len
= dso
->long_name_len
;
1069 curr_map
= map__new2(start
, curr_dso
,
1072 if (curr_map
== NULL
) {
1075 if (adjust_kernel_syms
) {
1076 curr_map
->start
= shdr
.sh_addr
+
1078 curr_map
->end
= curr_map
->start
+
1080 curr_map
->pgoff
= shdr
.sh_offset
;
1082 curr_map
->map_ip
= identity__map_ip
;
1083 curr_map
->unmap_ip
= identity__map_ip
;
1085 curr_dso
->symtab_type
= dso
->symtab_type
;
1086 map_groups__insert(kmaps
, curr_map
);
1088 * Add it before we drop the referece to curr_map,
1089 * i.e. while we still are sure to have a reference
1090 * to this DSO via curr_map->dso.
1092 dsos__add(&map
->groups
->machine
->dsos
, curr_dso
);
1093 /* kmaps already got it */
1095 dso__set_loaded(curr_dso
, map
->type
);
1097 curr_dso
= curr_map
->dso
;
1102 if ((used_opd
&& runtime_ss
->adjust_symbols
)
1103 || (!used_opd
&& syms_ss
->adjust_symbols
)) {
1104 pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64
" "
1105 "sh_addr: %#" PRIx64
" sh_offset: %#" PRIx64
"\n", __func__
,
1106 (u64
)sym
.st_value
, (u64
)shdr
.sh_addr
,
1107 (u64
)shdr
.sh_offset
);
1108 sym
.st_value
-= shdr
.sh_addr
- shdr
.sh_offset
;
1111 demangled
= demangle_sym(dso
, kmodule
, elf_name
);
1112 if (demangled
!= NULL
)
1113 elf_name
= demangled
;
1115 f
= symbol__new(sym
.st_value
, sym
.st_size
,
1116 GELF_ST_BIND(sym
.st_info
), elf_name
);
1121 arch__sym_update(f
, &sym
);
1123 __symbols__insert(&curr_dso
->symbols
[curr_map
->type
], f
, dso
->kernel
);
1128 * For misannotated, zeroed, ASM function sizes.
1131 symbols__fixup_end(&dso
->symbols
[map
->type
]);
1132 symbols__fixup_duplicate(&dso
->symbols
[map
->type
]);
1135 * We need to fixup this here too because we create new
1136 * maps here, for things like vsyscall sections.
1138 __map_groups__fixup_end(kmaps
, map
->type
);
1146 static int elf_read_maps(Elf
*elf
, bool exe
, mapfn_t mapfn
, void *data
)
1153 if (elf_getphdrnum(elf
, &phdrnum
))
1156 for (i
= 0; i
< phdrnum
; i
++) {
1157 if (gelf_getphdr(elf
, i
, &phdr
) == NULL
)
1159 if (phdr
.p_type
!= PT_LOAD
)
1162 if (!(phdr
.p_flags
& PF_X
))
1165 if (!(phdr
.p_flags
& PF_R
))
1168 sz
= min(phdr
.p_memsz
, phdr
.p_filesz
);
1171 err
= mapfn(phdr
.p_vaddr
, sz
, phdr
.p_offset
, data
);
1178 int file__read_maps(int fd
, bool exe
, mapfn_t mapfn
, void *data
,
1184 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
1189 *is_64_bit
= (gelf_getclass(elf
) == ELFCLASS64
);
1191 err
= elf_read_maps(elf
, exe
, mapfn
, data
);
1197 enum dso_type
dso__type_fd(int fd
)
1199 enum dso_type dso_type
= DSO__TYPE_UNKNOWN
;
1204 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
1209 if (ek
!= ELF_K_ELF
)
1212 if (gelf_getclass(elf
) == ELFCLASS64
) {
1213 dso_type
= DSO__TYPE_64BIT
;
1217 if (gelf_getehdr(elf
, &ehdr
) == NULL
)
1220 if (ehdr
.e_machine
== EM_X86_64
)
1221 dso_type
= DSO__TYPE_X32BIT
;
1223 dso_type
= DSO__TYPE_32BIT
;
1230 static int copy_bytes(int from
, off_t from_offs
, int to
, off_t to_offs
, u64 len
)
1235 char *buf
= malloc(page_size
);
1240 if (lseek(to
, to_offs
, SEEK_SET
) != to_offs
)
1243 if (lseek(from
, from_offs
, SEEK_SET
) != from_offs
)
1250 /* Use read because mmap won't work on proc files */
1251 r
= read(from
, buf
, n
);
1257 r
= write(to
, buf
, n
);
1278 static int kcore__open(struct kcore
*kcore
, const char *filename
)
1282 kcore
->fd
= open(filename
, O_RDONLY
);
1283 if (kcore
->fd
== -1)
1286 kcore
->elf
= elf_begin(kcore
->fd
, ELF_C_READ
, NULL
);
1290 kcore
->elfclass
= gelf_getclass(kcore
->elf
);
1291 if (kcore
->elfclass
== ELFCLASSNONE
)
1294 ehdr
= gelf_getehdr(kcore
->elf
, &kcore
->ehdr
);
1301 elf_end(kcore
->elf
);
1307 static int kcore__init(struct kcore
*kcore
, char *filename
, int elfclass
,
1310 kcore
->elfclass
= elfclass
;
1313 kcore
->fd
= mkstemp(filename
);
1315 kcore
->fd
= open(filename
, O_WRONLY
| O_CREAT
| O_EXCL
, 0400);
1316 if (kcore
->fd
== -1)
1319 kcore
->elf
= elf_begin(kcore
->fd
, ELF_C_WRITE
, NULL
);
1323 if (!gelf_newehdr(kcore
->elf
, elfclass
))
1326 memset(&kcore
->ehdr
, 0, sizeof(GElf_Ehdr
));
1331 elf_end(kcore
->elf
);
1338 static void kcore__close(struct kcore
*kcore
)
1340 elf_end(kcore
->elf
);
1344 static int kcore__copy_hdr(struct kcore
*from
, struct kcore
*to
, size_t count
)
1346 GElf_Ehdr
*ehdr
= &to
->ehdr
;
1347 GElf_Ehdr
*kehdr
= &from
->ehdr
;
1349 memcpy(ehdr
->e_ident
, kehdr
->e_ident
, EI_NIDENT
);
1350 ehdr
->e_type
= kehdr
->e_type
;
1351 ehdr
->e_machine
= kehdr
->e_machine
;
1352 ehdr
->e_version
= kehdr
->e_version
;
1355 ehdr
->e_flags
= kehdr
->e_flags
;
1356 ehdr
->e_phnum
= count
;
1357 ehdr
->e_shentsize
= 0;
1359 ehdr
->e_shstrndx
= 0;
1361 if (from
->elfclass
== ELFCLASS32
) {
1362 ehdr
->e_phoff
= sizeof(Elf32_Ehdr
);
1363 ehdr
->e_ehsize
= sizeof(Elf32_Ehdr
);
1364 ehdr
->e_phentsize
= sizeof(Elf32_Phdr
);
1366 ehdr
->e_phoff
= sizeof(Elf64_Ehdr
);
1367 ehdr
->e_ehsize
= sizeof(Elf64_Ehdr
);
1368 ehdr
->e_phentsize
= sizeof(Elf64_Phdr
);
1371 if (!gelf_update_ehdr(to
->elf
, ehdr
))
1374 if (!gelf_newphdr(to
->elf
, count
))
1380 static int kcore__add_phdr(struct kcore
*kcore
, int idx
, off_t offset
,
1385 .p_flags
= PF_R
| PF_W
| PF_X
,
1391 .p_align
= page_size
,
1394 if (!gelf_update_phdr(kcore
->elf
, idx
, &phdr
))
1400 static off_t
kcore__write(struct kcore
*kcore
)
1402 return elf_update(kcore
->elf
, ELF_C_WRITE
);
1411 struct kcore_copy_info
{
1417 u64 last_module_symbol
;
1418 struct phdr_data kernel_map
;
1419 struct phdr_data modules_map
;
1422 static int kcore_copy__process_kallsyms(void *arg
, const char *name
, char type
,
1425 struct kcore_copy_info
*kci
= arg
;
1427 if (!symbol_type__is_a(type
, MAP__FUNCTION
))
1430 if (strchr(name
, '[')) {
1431 if (start
> kci
->last_module_symbol
)
1432 kci
->last_module_symbol
= start
;
1436 if (!kci
->first_symbol
|| start
< kci
->first_symbol
)
1437 kci
->first_symbol
= start
;
1439 if (!kci
->last_symbol
|| start
> kci
->last_symbol
)
1440 kci
->last_symbol
= start
;
1442 if (!strcmp(name
, "_stext")) {
1447 if (!strcmp(name
, "_etext")) {
1455 static int kcore_copy__parse_kallsyms(struct kcore_copy_info
*kci
,
1458 char kallsyms_filename
[PATH_MAX
];
1460 scnprintf(kallsyms_filename
, PATH_MAX
, "%s/kallsyms", dir
);
1462 if (symbol__restricted_filename(kallsyms_filename
, "/proc/kallsyms"))
1465 if (kallsyms__parse(kallsyms_filename
, kci
,
1466 kcore_copy__process_kallsyms
) < 0)
1472 static int kcore_copy__process_modules(void *arg
,
1473 const char *name __maybe_unused
,
1476 struct kcore_copy_info
*kci
= arg
;
1478 if (!kci
->first_module
|| start
< kci
->first_module
)
1479 kci
->first_module
= start
;
1484 static int kcore_copy__parse_modules(struct kcore_copy_info
*kci
,
1487 char modules_filename
[PATH_MAX
];
1489 scnprintf(modules_filename
, PATH_MAX
, "%s/modules", dir
);
1491 if (symbol__restricted_filename(modules_filename
, "/proc/modules"))
1494 if (modules__parse(modules_filename
, kci
,
1495 kcore_copy__process_modules
) < 0)
1501 static void kcore_copy__map(struct phdr_data
*p
, u64 start
, u64 end
, u64 pgoff
,
1504 if (p
->addr
|| s
< start
|| s
>= end
)
1508 p
->offset
= (s
- start
) + pgoff
;
1509 p
->len
= e
< end
? e
- s
: end
- s
;
1512 static int kcore_copy__read_map(u64 start
, u64 len
, u64 pgoff
, void *data
)
1514 struct kcore_copy_info
*kci
= data
;
1515 u64 end
= start
+ len
;
1517 kcore_copy__map(&kci
->kernel_map
, start
, end
, pgoff
, kci
->stext
,
1520 kcore_copy__map(&kci
->modules_map
, start
, end
, pgoff
, kci
->first_module
,
1521 kci
->last_module_symbol
);
1526 static int kcore_copy__read_maps(struct kcore_copy_info
*kci
, Elf
*elf
)
1528 if (elf_read_maps(elf
, true, kcore_copy__read_map
, kci
) < 0)
1534 static int kcore_copy__calc_maps(struct kcore_copy_info
*kci
, const char *dir
,
1537 if (kcore_copy__parse_kallsyms(kci
, dir
))
1540 if (kcore_copy__parse_modules(kci
, dir
))
1544 kci
->stext
= round_down(kci
->stext
, page_size
);
1546 kci
->stext
= round_down(kci
->first_symbol
, page_size
);
1549 kci
->etext
= round_up(kci
->etext
, page_size
);
1550 } else if (kci
->last_symbol
) {
1551 kci
->etext
= round_up(kci
->last_symbol
, page_size
);
1552 kci
->etext
+= page_size
;
1555 kci
->first_module
= round_down(kci
->first_module
, page_size
);
1557 if (kci
->last_module_symbol
) {
1558 kci
->last_module_symbol
= round_up(kci
->last_module_symbol
,
1560 kci
->last_module_symbol
+= page_size
;
1563 if (!kci
->stext
|| !kci
->etext
)
1566 if (kci
->first_module
&& !kci
->last_module_symbol
)
1569 return kcore_copy__read_maps(kci
, elf
);
1572 static int kcore_copy__copy_file(const char *from_dir
, const char *to_dir
,
1575 char from_filename
[PATH_MAX
];
1576 char to_filename
[PATH_MAX
];
1578 scnprintf(from_filename
, PATH_MAX
, "%s/%s", from_dir
, name
);
1579 scnprintf(to_filename
, PATH_MAX
, "%s/%s", to_dir
, name
);
1581 return copyfile_mode(from_filename
, to_filename
, 0400);
1584 static int kcore_copy__unlink(const char *dir
, const char *name
)
1586 char filename
[PATH_MAX
];
1588 scnprintf(filename
, PATH_MAX
, "%s/%s", dir
, name
);
1590 return unlink(filename
);
1593 static int kcore_copy__compare_fds(int from
, int to
)
1601 buf_from
= malloc(page_size
);
1602 buf_to
= malloc(page_size
);
1603 if (!buf_from
|| !buf_to
)
1607 /* Use read because mmap won't work on proc files */
1608 ret
= read(from
, buf_from
, page_size
);
1617 if (readn(to
, buf_to
, len
) != (int)len
)
1620 if (memcmp(buf_from
, buf_to
, len
))
1631 static int kcore_copy__compare_files(const char *from_filename
,
1632 const char *to_filename
)
1634 int from
, to
, err
= -1;
1636 from
= open(from_filename
, O_RDONLY
);
1640 to
= open(to_filename
, O_RDONLY
);
1642 goto out_close_from
;
1644 err
= kcore_copy__compare_fds(from
, to
);
1652 static int kcore_copy__compare_file(const char *from_dir
, const char *to_dir
,
1655 char from_filename
[PATH_MAX
];
1656 char to_filename
[PATH_MAX
];
1658 scnprintf(from_filename
, PATH_MAX
, "%s/%s", from_dir
, name
);
1659 scnprintf(to_filename
, PATH_MAX
, "%s/%s", to_dir
, name
);
1661 return kcore_copy__compare_files(from_filename
, to_filename
);
1665 * kcore_copy - copy kallsyms, modules and kcore from one directory to another.
1666 * @from_dir: from directory
1667 * @to_dir: to directory
1669 * This function copies kallsyms, modules and kcore files from one directory to
1670 * another. kallsyms and modules are copied entirely. Only code segments are
1671 * copied from kcore. It is assumed that two segments suffice: one for the
1672 * kernel proper and one for all the modules. The code segments are determined
1673 * from kallsyms and modules files. The kernel map starts at _stext or the
1674 * lowest function symbol, and ends at _etext or the highest function symbol.
1675 * The module map starts at the lowest module address and ends at the highest
1676 * module symbol. Start addresses are rounded down to the nearest page. End
1677 * addresses are rounded up to the nearest page. An extra page is added to the
1678 * highest kernel symbol and highest module symbol to, hopefully, encompass that
1679 * symbol too. Because it contains only code sections, the resulting kcore is
1680 * unusual. One significant peculiarity is that the mapping (start -> pgoff)
1681 * is not the same for the kernel map and the modules map. That happens because
1682 * the data is copied adjacently whereas the original kcore has gaps. Finally,
1683 * kallsyms and modules files are compared with their copies to check that
1684 * modules have not been loaded or unloaded while the copies were taking place.
1686 * Return: %0 on success, %-1 on failure.
1688 int kcore_copy(const char *from_dir
, const char *to_dir
)
1691 struct kcore extract
;
1693 int idx
= 0, err
= -1;
1694 off_t offset
= page_size
, sz
, modules_offset
= 0;
1695 struct kcore_copy_info kci
= { .stext
= 0, };
1696 char kcore_filename
[PATH_MAX
];
1697 char extract_filename
[PATH_MAX
];
1699 if (kcore_copy__copy_file(from_dir
, to_dir
, "kallsyms"))
1702 if (kcore_copy__copy_file(from_dir
, to_dir
, "modules"))
1703 goto out_unlink_kallsyms
;
1705 scnprintf(kcore_filename
, PATH_MAX
, "%s/kcore", from_dir
);
1706 scnprintf(extract_filename
, PATH_MAX
, "%s/kcore", to_dir
);
1708 if (kcore__open(&kcore
, kcore_filename
))
1709 goto out_unlink_modules
;
1711 if (kcore_copy__calc_maps(&kci
, from_dir
, kcore
.elf
))
1712 goto out_kcore_close
;
1714 if (kcore__init(&extract
, extract_filename
, kcore
.elfclass
, false))
1715 goto out_kcore_close
;
1717 if (!kci
.modules_map
.addr
)
1720 if (kcore__copy_hdr(&kcore
, &extract
, count
))
1721 goto out_extract_close
;
1723 if (kcore__add_phdr(&extract
, idx
++, offset
, kci
.kernel_map
.addr
,
1724 kci
.kernel_map
.len
))
1725 goto out_extract_close
;
1727 if (kci
.modules_map
.addr
) {
1728 modules_offset
= offset
+ kci
.kernel_map
.len
;
1729 if (kcore__add_phdr(&extract
, idx
, modules_offset
,
1730 kci
.modules_map
.addr
, kci
.modules_map
.len
))
1731 goto out_extract_close
;
1734 sz
= kcore__write(&extract
);
1735 if (sz
< 0 || sz
> offset
)
1736 goto out_extract_close
;
1738 if (copy_bytes(kcore
.fd
, kci
.kernel_map
.offset
, extract
.fd
, offset
,
1739 kci
.kernel_map
.len
))
1740 goto out_extract_close
;
1742 if (modules_offset
&& copy_bytes(kcore
.fd
, kci
.modules_map
.offset
,
1743 extract
.fd
, modules_offset
,
1744 kci
.modules_map
.len
))
1745 goto out_extract_close
;
1747 if (kcore_copy__compare_file(from_dir
, to_dir
, "modules"))
1748 goto out_extract_close
;
1750 if (kcore_copy__compare_file(from_dir
, to_dir
, "kallsyms"))
1751 goto out_extract_close
;
1756 kcore__close(&extract
);
1758 unlink(extract_filename
);
1760 kcore__close(&kcore
);
1763 kcore_copy__unlink(to_dir
, "modules");
1764 out_unlink_kallsyms
:
1766 kcore_copy__unlink(to_dir
, "kallsyms");
1771 int kcore_extract__create(struct kcore_extract
*kce
)
1774 struct kcore extract
;
1776 int idx
= 0, err
= -1;
1777 off_t offset
= page_size
, sz
;
1779 if (kcore__open(&kcore
, kce
->kcore_filename
))
1782 strcpy(kce
->extract_filename
, PERF_KCORE_EXTRACT
);
1783 if (kcore__init(&extract
, kce
->extract_filename
, kcore
.elfclass
, true))
1784 goto out_kcore_close
;
1786 if (kcore__copy_hdr(&kcore
, &extract
, count
))
1787 goto out_extract_close
;
1789 if (kcore__add_phdr(&extract
, idx
, offset
, kce
->addr
, kce
->len
))
1790 goto out_extract_close
;
1792 sz
= kcore__write(&extract
);
1793 if (sz
< 0 || sz
> offset
)
1794 goto out_extract_close
;
1796 if (copy_bytes(kcore
.fd
, kce
->offs
, extract
.fd
, offset
, kce
->len
))
1797 goto out_extract_close
;
1802 kcore__close(&extract
);
1804 unlink(kce
->extract_filename
);
1806 kcore__close(&kcore
);
1811 void kcore_extract__delete(struct kcore_extract
*kce
)
1813 unlink(kce
->extract_filename
);
1816 #ifdef HAVE_GELF_GETNOTE_SUPPORT
1818 * populate_sdt_note : Parse raw data and identify SDT note
1819 * @elf: elf of the opened file
1820 * @data: raw data of a section with description offset applied
1821 * @len: note description size
1822 * @type: type of the note
1823 * @sdt_notes: List to add the SDT note
1825 * Responsible for parsing the @data in section .note.stapsdt in @elf and
1826 * if its an SDT note, it appends to @sdt_notes list.
1828 static int populate_sdt_note(Elf
**elf
, const char *data
, size_t len
,
1829 struct list_head
*sdt_notes
)
1831 const char *provider
, *name
, *args
;
1832 struct sdt_note
*tmp
= NULL
;
1834 GElf_Addr base_off
= 0;
1839 Elf64_Addr a64
[NR_ADDR
];
1840 Elf32_Addr a32
[NR_ADDR
];
1844 .d_buf
= &buf
, .d_type
= ELF_T_ADDR
, .d_version
= EV_CURRENT
,
1845 .d_size
= gelf_fsize((*elf
), ELF_T_ADDR
, NR_ADDR
, EV_CURRENT
),
1846 .d_off
= 0, .d_align
= 0
1849 .d_buf
= (void *) data
, .d_type
= ELF_T_ADDR
,
1850 .d_version
= EV_CURRENT
, .d_size
= dst
.d_size
, .d_off
= 0,
1854 tmp
= (struct sdt_note
*)calloc(1, sizeof(struct sdt_note
));
1860 INIT_LIST_HEAD(&tmp
->note_list
);
1862 if (len
< dst
.d_size
+ 3)
1865 /* Translation from file representation to memory representation */
1866 if (gelf_xlatetom(*elf
, &dst
, &src
,
1867 elf_getident(*elf
, NULL
)[EI_DATA
]) == NULL
) {
1868 pr_err("gelf_xlatetom : %s\n", elf_errmsg(-1));
1872 /* Populate the fields of sdt_note */
1873 provider
= data
+ dst
.d_size
;
1875 name
= (const char *)memchr(provider
, '\0', data
+ len
- provider
);
1879 tmp
->provider
= strdup(provider
);
1880 if (!tmp
->provider
) {
1884 tmp
->name
= strdup(name
);
1890 args
= memchr(name
, '\0', data
+ len
- name
);
1893 * There is no argument if:
1894 * - We reached the end of the note;
1895 * - There is not enough room to hold a potential string;
1896 * - The argument string is empty or just contains ':'.
1898 if (args
== NULL
|| data
+ len
- args
< 2 ||
1899 args
[1] == ':' || args
[1] == '\0')
1902 tmp
->args
= strdup(++args
);
1909 if (gelf_getclass(*elf
) == ELFCLASS32
) {
1910 memcpy(&tmp
->addr
, &buf
, 3 * sizeof(Elf32_Addr
));
1913 memcpy(&tmp
->addr
, &buf
, 3 * sizeof(Elf64_Addr
));
1917 if (!gelf_getehdr(*elf
, &ehdr
)) {
1918 pr_debug("%s : cannot get elf header.\n", __func__
);
1923 /* Adjust the prelink effect :
1924 * Find out the .stapsdt.base section.
1925 * This scn will help us to handle prelinking (if present).
1926 * Compare the retrieved file offset of the base section with the
1927 * base address in the description of the SDT note. If its different,
1928 * then accordingly, adjust the note location.
1930 if (elf_section_by_name(*elf
, &ehdr
, &shdr
, SDT_BASE_SCN
, NULL
)) {
1931 base_off
= shdr
.sh_offset
;
1934 tmp
->addr
.a32
[0] = tmp
->addr
.a32
[0] + base_off
-
1937 tmp
->addr
.a64
[0] = tmp
->addr
.a64
[0] + base_off
-
1942 list_add_tail(&tmp
->note_list
, sdt_notes
);
1950 free(tmp
->provider
);
1958 * construct_sdt_notes_list : constructs a list of SDT notes
1959 * @elf : elf to look into
1960 * @sdt_notes : empty list_head
1962 * Scans the sections in 'elf' for the section
1963 * .note.stapsdt. It, then calls populate_sdt_note to find
1964 * out the SDT events and populates the 'sdt_notes'.
1966 static int construct_sdt_notes_list(Elf
*elf
, struct list_head
*sdt_notes
)
1969 Elf_Scn
*scn
= NULL
;
1972 size_t shstrndx
, next
;
1974 size_t name_off
, desc_off
, offset
;
1977 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
1981 if (elf_getshdrstrndx(elf
, &shstrndx
) != 0) {
1986 /* Look for the required section */
1987 scn
= elf_section_by_name(elf
, &ehdr
, &shdr
, SDT_NOTE_SCN
, NULL
);
1993 if ((shdr
.sh_type
!= SHT_NOTE
) || (shdr
.sh_flags
& SHF_ALLOC
)) {
1998 data
= elf_getdata(scn
, NULL
);
2000 /* Get the SDT notes */
2001 for (offset
= 0; (next
= gelf_getnote(data
, offset
, &nhdr
, &name_off
,
2002 &desc_off
)) > 0; offset
= next
) {
2003 if (nhdr
.n_namesz
== sizeof(SDT_NOTE_NAME
) &&
2004 !memcmp(data
->d_buf
+ name_off
, SDT_NOTE_NAME
,
2005 sizeof(SDT_NOTE_NAME
))) {
2006 /* Check the type of the note */
2007 if (nhdr
.n_type
!= SDT_NOTE_TYPE
)
2010 ret
= populate_sdt_note(&elf
, ((data
->d_buf
) + desc_off
),
2011 nhdr
.n_descsz
, sdt_notes
);
2016 if (list_empty(sdt_notes
))
2024 * get_sdt_note_list : Wrapper to construct a list of sdt notes
2025 * @head : empty list_head
2026 * @target : file to find SDT notes from
2028 * This opens the file, initializes
2029 * the ELF and then calls construct_sdt_notes_list.
2031 int get_sdt_note_list(struct list_head
*head
, const char *target
)
2036 fd
= open(target
, O_RDONLY
);
2040 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
2045 ret
= construct_sdt_notes_list(elf
, head
);
2053 * cleanup_sdt_note_list : free the sdt notes' list
2054 * @sdt_notes: sdt notes' list
2056 * Free up the SDT notes in @sdt_notes.
2057 * Returns the number of SDT notes free'd.
2059 int cleanup_sdt_note_list(struct list_head
*sdt_notes
)
2061 struct sdt_note
*tmp
, *pos
;
2064 list_for_each_entry_safe(pos
, tmp
, sdt_notes
, note_list
) {
2065 list_del(&pos
->note_list
);
2067 free(pos
->provider
);
2075 * sdt_notes__get_count: Counts the number of sdt events
2076 * @start: list_head to sdt_notes list
2078 * Returns the number of SDT notes in a list
2080 int sdt_notes__get_count(struct list_head
*start
)
2082 struct sdt_note
*sdt_ptr
;
2085 list_for_each_entry(sdt_ptr
, start
, note_list
)
2091 void symbol__elf_init(void)
2093 elf_version(EV_CURRENT
);