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-rw-r--r--tools/perf/util/symbol.c407
1 files changed, 337 insertions, 70 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 86e14375e74..16ddca20294 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -7,8 +7,23 @@
#include <gelf.h>
#include <elf.h>
+#ifndef NO_DEMANGLE
+#include <bfd.h>
+#else
+static inline
+char *bfd_demangle(void __used *v, const char __used *c, int __used i)
+{
+ return NULL;
+}
+#endif
+
const char *sym_hist_filter;
+#ifndef DMGL_PARAMS
+#define DMGL_PARAMS (1 << 0) /* Include function args */
+#define DMGL_ANSI (1 << 1) /* Include const, volatile, etc */
+#endif
+
static struct symbol *symbol__new(u64 start, u64 len,
const char *name, unsigned int priv_size,
u64 obj_start, int verbose)
@@ -35,7 +50,7 @@ static struct symbol *symbol__new(u64 start, u64 len,
self = ((void *)self) + priv_size;
}
self->start = start;
- self->end = start + len - 1;
+ self->end = len ? start + len - 1 : start;
memcpy(self->name, name, namelen);
return self;
@@ -48,8 +63,12 @@ static void symbol__delete(struct symbol *self, unsigned int priv_size)
static size_t symbol__fprintf(struct symbol *self, FILE *fp)
{
- return fprintf(fp, " %llx-%llx %s\n",
+ if (!self->module)
+ return fprintf(fp, " %llx-%llx %s\n",
self->start, self->end, self->name);
+ else
+ return fprintf(fp, " %llx-%llx %s \t[%s]\n",
+ self->start, self->end, self->name, self->module->name);
}
struct dso *dso__new(const char *name, unsigned int sym_priv_size)
@@ -61,6 +80,7 @@ struct dso *dso__new(const char *name, unsigned int sym_priv_size)
self->syms = RB_ROOT;
self->sym_priv_size = sym_priv_size;
self->find_symbol = dso__find_symbol;
+ self->slen_calculated = 0;
}
return self;
@@ -146,6 +166,7 @@ static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int verb
char *line = NULL;
size_t n;
FILE *file = fopen("/proc/kallsyms", "r");
+ int count = 0;
if (file == NULL)
goto out_failure;
@@ -188,8 +209,10 @@ static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int verb
if (filter && filter(self, sym))
symbol__delete(sym, self->sym_priv_size);
- else
+ else {
dso__insert_symbol(self, sym);
+ count++;
+ }
}
/*
@@ -212,7 +235,7 @@ static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int verb
free(line);
fclose(file);
- return 0;
+ return count;
out_delete_line:
free(line);
@@ -307,6 +330,26 @@ static inline int elf_sym__is_function(const GElf_Sym *sym)
sym->st_size != 0;
}
+static inline int elf_sym__is_label(const GElf_Sym *sym)
+{
+ return elf_sym__type(sym) == STT_NOTYPE &&
+ sym->st_name != 0 &&
+ sym->st_shndx != SHN_UNDEF &&
+ sym->st_shndx != SHN_ABS;
+}
+
+static inline const char *elf_sec__name(const GElf_Shdr *shdr,
+ const Elf_Data *secstrs)
+{
+ return secstrs->d_buf + shdr->sh_name;
+}
+
+static inline int elf_sec__is_text(const GElf_Shdr *shdr,
+ const Elf_Data *secstrs)
+{
+ return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
+}
+
static inline const char *elf_sym__name(const GElf_Sym *sym,
const Elf_Data *symstrs)
{
@@ -346,36 +389,61 @@ static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
idx < nr_entries; \
++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
-static int dso__synthesize_plt_symbols(struct dso *self, Elf *elf,
- GElf_Ehdr *ehdr, Elf_Scn *scn_dynsym,
- GElf_Shdr *shdr_dynsym,
- size_t dynsym_idx, int verbose)
+/*
+ * We need to check if we have a .dynsym, so that we can handle the
+ * .plt, synthesizing its symbols, that aren't on the symtabs (be it
+ * .dynsym or .symtab).
+ * And always look at the original dso, not at debuginfo packages, that
+ * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
+ */
+static int dso__synthesize_plt_symbols(struct dso *self, int verbose)
{
uint32_t nr_rel_entries, idx;
GElf_Sym sym;
u64 plt_offset;
GElf_Shdr shdr_plt;
struct symbol *f;
- GElf_Shdr shdr_rel_plt;
+ GElf_Shdr shdr_rel_plt, shdr_dynsym;
Elf_Data *reldata, *syms, *symstrs;
- Elf_Scn *scn_plt_rel, *scn_symstrs;
+ Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
+ size_t dynsym_idx;
+ GElf_Ehdr ehdr;
char sympltname[1024];
- int nr = 0, symidx;
+ Elf *elf;
+ int nr = 0, symidx, fd, err = 0;
+
+ fd = open(self->name, O_RDONLY);
+ if (fd < 0)
+ goto out;
+
+ elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
+ if (elf == NULL)
+ goto out_close;
+
+ if (gelf_getehdr(elf, &ehdr) == NULL)
+ goto out_elf_end;
+
+ scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
+ ".dynsym", &dynsym_idx);
+ if (scn_dynsym == NULL)
+ goto out_elf_end;
- scn_plt_rel = elf_section_by_name(elf, ehdr, &shdr_rel_plt,
+ scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
".rela.plt", NULL);
if (scn_plt_rel == NULL) {
- scn_plt_rel = elf_section_by_name(elf, ehdr, &shdr_rel_plt,
+ scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
".rel.plt", NULL);
if (scn_plt_rel == NULL)
- return 0;
+ goto out_elf_end;
}
+ err = -1;
+
if (shdr_rel_plt.sh_link != dynsym_idx)
- return 0;
+ goto out_elf_end;
- if (elf_section_by_name(elf, ehdr, &shdr_plt, ".plt", NULL) == NULL)
- return 0;
+ if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
+ goto out_elf_end;
/*
* Fetch the relocation section to find the indexes to the GOT
@@ -383,19 +451,19 @@ static int dso__synthesize_plt_symbols(struct dso *self, Elf *elf,
*/
reldata = elf_getdata(scn_plt_rel, NULL);
if (reldata == NULL)
- return -1;
+ goto out_elf_end;
syms = elf_getdata(scn_dynsym, NULL);
if (syms == NULL)
- return -1;
+ goto out_elf_end;
- scn_symstrs = elf_getscn(elf, shdr_dynsym->sh_link);
+ scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
if (scn_symstrs == NULL)
- return -1;
+ goto out_elf_end;
symstrs = elf_getdata(scn_symstrs, NULL);
if (symstrs == NULL)
- return -1;
+ goto out_elf_end;
nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
plt_offset = shdr_plt.sh_offset;
@@ -414,7 +482,7 @@ static int dso__synthesize_plt_symbols(struct dso *self, Elf *elf,
f = symbol__new(plt_offset, shdr_plt.sh_entsize,
sympltname, self->sym_priv_size, 0, verbose);
if (!f)
- return -1;
+ goto out_elf_end;
dso__insert_symbol(self, f);
++nr;
@@ -432,25 +500,31 @@ static int dso__synthesize_plt_symbols(struct dso *self, Elf *elf,
f = symbol__new(plt_offset, shdr_plt.sh_entsize,
sympltname, self->sym_priv_size, 0, verbose);
if (!f)
- return -1;
+ goto out_elf_end;
dso__insert_symbol(self, f);
++nr;
}
- } else {
- /*
- * TODO: There are still one more shdr_rel_plt.sh_type
- * I have to investigate, but probably should be ignored.
- */
}
- return nr;
+ err = 0;
+out_elf_end:
+ elf_end(elf);
+out_close:
+ close(fd);
+
+ if (err == 0)
+ return nr;
+out:
+ fprintf(stderr, "%s: problems reading %s PLT info.\n",
+ __func__, self->name);
+ return 0;
}
static int dso__load_sym(struct dso *self, int fd, const char *name,
- symbol_filter_t filter, int verbose)
+ symbol_filter_t filter, int verbose, struct module *mod)
{
- Elf_Data *symstrs;
+ Elf_Data *symstrs, *secstrs;
uint32_t nr_syms;
int err = -1;
uint32_t index;
@@ -458,10 +532,9 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
GElf_Shdr shdr;
Elf_Data *syms;
GElf_Sym sym;
- Elf_Scn *sec, *sec_dynsym;
+ Elf_Scn *sec, *sec_strndx;
Elf *elf;
- size_t dynsym_idx;
- int nr = 0;
+ int nr = 0, kernel = !strcmp("[kernel]", self->name);
elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
if (elf == NULL) {
@@ -477,32 +550,11 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
goto out_elf_end;
}
- /*
- * We need to check if we have a .dynsym, so that we can handle the
- * .plt, synthesizing its symbols, that aren't on the symtabs (be it
- * .dynsym or .symtab)
- */
- sec_dynsym = elf_section_by_name(elf, &ehdr, &shdr,
- ".dynsym", &dynsym_idx);
- if (sec_dynsym != NULL) {
- nr = dso__synthesize_plt_symbols(self, elf, &ehdr,
- sec_dynsym, &shdr,
- dynsym_idx, verbose);
- if (nr < 0)
- goto out_elf_end;
- }
-
- /*
- * But if we have a full .symtab (that is a superset of .dynsym) we
- * should add the symbols not in the .dynsyn
- */
sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
if (sec == NULL) {
- if (sec_dynsym == NULL)
+ sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
+ if (sec == NULL)
goto out_elf_end;
-
- sec = sec_dynsym;
- gelf_getshdr(sec, &shdr);
}
syms = elf_getdata(sec, NULL);
@@ -517,15 +569,34 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
if (symstrs == NULL)
goto out_elf_end;
+ sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
+ if (sec_strndx == NULL)
+ goto out_elf_end;
+
+ secstrs = elf_getdata(sec_strndx, NULL);
+ if (secstrs == NULL)
+ goto out_elf_end;
+
nr_syms = shdr.sh_size / shdr.sh_entsize;
memset(&sym, 0, sizeof(sym));
+ if (!kernel) {
+ self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
+ elf_section_by_name(elf, &ehdr, &shdr,
+ ".gnu.prelink_undo",
+ NULL) != NULL);
+ } else self->adjust_symbols = 0;
elf_symtab__for_each_symbol(syms, nr_syms, index, sym) {
struct symbol *f;
+ const char *name;
+ char *demangled;
u64 obj_start;
+ struct section *section = NULL;
+ int is_label = elf_sym__is_label(&sym);
+ const char *section_name;
- if (!elf_sym__is_function(&sym))
+ if (!is_label && !elf_sym__is_function(&sym))
continue;
sec = elf_getscn(elf, sym.st_shndx);
@@ -533,19 +604,51 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
goto out_elf_end;
gelf_getshdr(sec, &shdr);
+
+ if (is_label && !elf_sec__is_text(&shdr, secstrs))
+ continue;
+
+ section_name = elf_sec__name(&shdr, secstrs);
obj_start = sym.st_value;
- sym.st_value -= shdr.sh_addr - shdr.sh_offset;
+ if (self->adjust_symbols) {
+ if (verbose >= 2)
+ printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n",
+ (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset);
+
+ sym.st_value -= shdr.sh_addr - shdr.sh_offset;
+ }
- f = symbol__new(sym.st_value, sym.st_size,
- elf_sym__name(&sym, symstrs),
+ if (mod) {
+ section = mod->sections->find_section(mod->sections, section_name);
+ if (section)
+ sym.st_value += section->vma;
+ else {
+ fprintf(stderr, "dso__load_sym() module %s lookup of %s failed\n",
+ mod->name, section_name);
+ goto out_elf_end;
+ }
+ }
+ /*
+ * We need to figure out if the object was created from C++ sources
+ * DWARF DW_compile_unit has this, but we don't always have access
+ * to it...
+ */
+ name = elf_sym__name(&sym, symstrs);
+ demangled = bfd_demangle(NULL, name, DMGL_PARAMS | DMGL_ANSI);
+ if (demangled != NULL)
+ name = demangled;
+
+ f = symbol__new(sym.st_value, sym.st_size, name,
self->sym_priv_size, obj_start, verbose);
+ free(demangled);
if (!f)
goto out_elf_end;
if (filter && filter(self, f))
symbol__delete(f, self->sym_priv_size);
else {
+ f->module = mod;
dso__insert_symbol(self, f);
nr++;
}
@@ -558,10 +661,69 @@ out_close:
return err;
}
+#define BUILD_ID_SIZE 128
+
+static char *dso__read_build_id(struct dso *self, int verbose)
+{
+ int i;
+ GElf_Ehdr ehdr;
+ GElf_Shdr shdr;
+ Elf_Data *build_id_data;
+ Elf_Scn *sec;
+ char *build_id = NULL, *bid;
+ unsigned char *raw;
+ Elf *elf;
+ int fd = open(self->name, O_RDONLY);
+
+ if (fd < 0)
+ goto out;
+
+ elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
+ if (elf == NULL) {
+ if (verbose)
+ fprintf(stderr, "%s: cannot read %s ELF file.\n",
+ __func__, self->name);
+ goto out_close;
+ }
+
+ if (gelf_getehdr(elf, &ehdr) == NULL) {
+ if (verbose)
+ fprintf(stderr, "%s: cannot get elf header.\n", __func__);
+ goto out_elf_end;
+ }
+
+ sec = elf_section_by_name(elf, &ehdr, &shdr, ".note.gnu.build-id", NULL);
+ if (sec == NULL)
+ goto out_elf_end;
+
+ build_id_data = elf_getdata(sec, NULL);
+ if (build_id_data == NULL)
+ goto out_elf_end;
+ build_id = malloc(BUILD_ID_SIZE);
+ if (build_id == NULL)
+ goto out_elf_end;
+ raw = build_id_data->d_buf + 16;
+ bid = build_id;
+
+ for (i = 0; i < 20; ++i) {
+ sprintf(bid, "%02x", *raw);
+ ++raw;
+ bid += 2;
+ }
+ if (verbose)
+ printf("%s(%s): %s\n", __func__, self->name, build_id);
+out_elf_end:
+ elf_end(elf);
+out_close:
+ close(fd);
+out:
+ return build_id;
+}
+
int dso__load(struct dso *self, symbol_filter_t filter, int verbose)
{
- int size = strlen(self->name) + sizeof("/usr/lib/debug%s.debug");
- char *name = malloc(size);
+ int size = PATH_MAX;
+ char *name = malloc(size), *build_id = NULL;
int variant = 0;
int ret = -1;
int fd;
@@ -569,6 +731,8 @@ int dso__load(struct dso *self, symbol_filter_t filter, int verbose)
if (!name)
return -1;
+ self->adjust_symbols = 0;
+
if (strncmp(self->name, "/tmp/perf-", 10) == 0)
return dso__load_perf_map(self, filter, verbose);
@@ -581,7 +745,18 @@ more:
case 1: /* Ubuntu */
snprintf(name, size, "/usr/lib/debug%s", self->name);
break;
- case 2: /* Sane people */
+ case 2:
+ build_id = dso__read_build_id(self, verbose);
+ if (build_id != NULL) {
+ snprintf(name, size,
+ "/usr/lib/debug/.build-id/%.2s/%s.debug",
+ build_id, build_id + 2);
+ free(build_id);
+ break;
+ }
+ variant++;
+ /* Fall thru */
+ case 3: /* Sane people */
snprintf(name, size, "%s", self->name);
break;
@@ -593,7 +768,7 @@ more:
fd = open(name, O_RDONLY);
} while (fd < 0);
- ret = dso__load_sym(self, fd, name, filter, verbose);
+ ret = dso__load_sym(self, fd, name, filter, verbose, NULL);
close(fd);
/*
@@ -602,11 +777,96 @@ more:
if (!ret)
goto more;
+ if (ret > 0) {
+ int nr_plt = dso__synthesize_plt_symbols(self, verbose);
+ if (nr_plt > 0)
+ ret += nr_plt;
+ }
out:
free(name);
return ret;
}
+static int dso__load_module(struct dso *self, struct mod_dso *mods, const char *name,
+ symbol_filter_t filter, int verbose)
+{
+ struct module *mod = mod_dso__find_module(mods, name);
+ int err = 0, fd;
+
+ if (mod == NULL || !mod->active)
+ return err;
+
+ fd = open(mod->path, O_RDONLY);
+
+ if (fd < 0)
+ return err;
+
+ err = dso__load_sym(self, fd, name, filter, verbose, mod);
+ close(fd);
+
+ return err;
+}
+
+int dso__load_modules(struct dso *self, symbol_filter_t filter, int verbose)
+{
+ struct mod_dso *mods = mod_dso__new_dso("modules");
+ struct module *pos;
+ struct rb_node *next;
+ int err;
+
+ err = mod_dso__load_modules(mods);
+
+ if (err <= 0)
+ return err;
+
+ /*
+ * Iterate over modules, and load active symbols.
+ */
+ next = rb_first(&mods->mods);
+ while (next) {
+ pos = rb_entry(next, struct module, rb_node);
+ err = dso__load_module(self, mods, pos->name, filter, verbose);
+
+ if (err < 0)
+ break;
+
+ next = rb_next(&pos->rb_node);
+ }
+
+ if (err < 0) {
+ mod_dso__delete_modules(mods);
+ mod_dso__delete_self(mods);
+ }
+
+ return err;
+}
+
+static inline void dso__fill_symbol_holes(struct dso *self)
+{
+ struct symbol *prev = NULL;
+ struct rb_node *nd;
+
+ for (nd = rb_last(&self->syms); nd; nd = rb_prev(nd)) {
+ struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
+
+ if (prev) {
+ u64 hole = 0;
+ int alias = pos->start == prev->start;
+
+ if (!alias)
+ hole = prev->start - pos->end - 1;
+
+ if (hole || alias) {
+ if (alias)
+ pos->end = prev->end;
+ else if (hole)
+ pos->end = prev->start - 1;
+ }
+ }
+ prev = pos;
+ }
+}
+
static int dso__load_vmlinux(struct dso *self, const char *vmlinux,
symbol_filter_t filter, int verbose)
{
@@ -615,21 +875,28 @@ static int dso__load_vmlinux(struct dso *self, const char *vmlinux,
if (fd < 0)
return -1;
- err = dso__load_sym(self, fd, vmlinux, filter, verbose);
+ err = dso__load_sym(self, fd, vmlinux, filter, verbose, NULL);
+
+ if (err > 0)
+ dso__fill_symbol_holes(self);
+
close(fd);
return err;
}
int dso__load_kernel(struct dso *self, const char *vmlinux,
- symbol_filter_t filter, int verbose)
+ symbol_filter_t filter, int verbose, int modules)
{
int err = -1;
- if (vmlinux)
+ if (vmlinux) {
err = dso__load_vmlinux(self, vmlinux, filter, verbose);
+ if (err > 0 && modules)
+ err = dso__load_modules(self, filter, verbose);
+ }
- if (err)
+ if (err <= 0)
err = dso__load_kallsyms(self, filter, verbose);
return err;
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-11 14:53:04 +0000