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-rw-r--r--tools/perf/util/symbol.c153
1 files changed, 118 insertions, 35 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 469c0264ed29..40eeaf07725b 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -74,16 +74,104 @@ static void dso__set_sorted_by_name(struct dso *dso, enum map_type type)
bool symbol_type__is_a(char symbol_type, enum map_type map_type)
{
+ symbol_type = toupper(symbol_type);
+
switch (map_type) {
case MAP__FUNCTION:
return symbol_type == 'T' || symbol_type == 'W';
case MAP__VARIABLE:
- return symbol_type == 'D' || symbol_type == 'd';
+ return symbol_type == 'D';
default:
return false;
}
}
+static int prefix_underscores_count(const char *str)
+{
+ const char *tail = str;
+
+ while (*tail == '_')
+ tail++;
+
+ return tail - str;
+}
+
+#define SYMBOL_A 0
+#define SYMBOL_B 1
+
+static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
+{
+ s64 a;
+ s64 b;
+
+ /* Prefer a symbol with non zero length */
+ a = syma->end - syma->start;
+ b = symb->end - symb->start;
+ if ((b == 0) && (a > 0))
+ return SYMBOL_A;
+ else if ((a == 0) && (b > 0))
+ return SYMBOL_B;
+
+ /* Prefer a non weak symbol over a weak one */
+ a = syma->binding == STB_WEAK;
+ b = symb->binding == STB_WEAK;
+ if (b && !a)
+ return SYMBOL_A;
+ if (a && !b)
+ return SYMBOL_B;
+
+ /* Prefer a global symbol over a non global one */
+ a = syma->binding == STB_GLOBAL;
+ b = symb->binding == STB_GLOBAL;
+ if (a && !b)
+ return SYMBOL_A;
+ if (b && !a)
+ return SYMBOL_B;
+
+ /* Prefer a symbol with less underscores */
+ a = prefix_underscores_count(syma->name);
+ b = prefix_underscores_count(symb->name);
+ if (b > a)
+ return SYMBOL_A;
+ else if (a > b)
+ return SYMBOL_B;
+
+ /* If all else fails, choose the symbol with the longest name */
+ if (strlen(syma->name) >= strlen(symb->name))
+ return SYMBOL_A;
+ else
+ return SYMBOL_B;
+}
+
+static void symbols__fixup_duplicate(struct rb_root *symbols)
+{
+ struct rb_node *nd;
+ struct symbol *curr, *next;
+
+ nd = rb_first(symbols);
+
+ while (nd) {
+ curr = rb_entry(nd, struct symbol, rb_node);
+again:
+ nd = rb_next(&curr->rb_node);
+ next = rb_entry(nd, struct symbol, rb_node);
+
+ if (!nd)
+ break;
+
+ if (curr->start != next->start)
+ continue;
+
+ if (choose_best_symbol(curr, next) == SYMBOL_A) {
+ rb_erase(&next->rb_node, symbols);
+ goto again;
+ } else {
+ nd = rb_next(&curr->rb_node);
+ rb_erase(&curr->rb_node, symbols);
+ }
+ }
+}
+
static void symbols__fixup_end(struct rb_root *symbols)
{
struct rb_node *nd, *prevnd = rb_first(symbols);
@@ -438,18 +526,11 @@ int kallsyms__parse(const char *filename, void *arg,
char *line = NULL;
size_t n;
int err = -1;
- u64 prev_start = 0;
- char prev_symbol_type = 0;
- char *prev_symbol_name;
FILE *file = fopen(filename, "r");
if (file == NULL)
goto out_failure;
- prev_symbol_name = malloc(KSYM_NAME_LEN);
- if (prev_symbol_name == NULL)
- goto out_close;
-
err = 0;
while (!feof(file)) {
@@ -470,7 +551,7 @@ int kallsyms__parse(const char *filename, void *arg,
if (len + 2 >= line_len)
continue;
- symbol_type = toupper(line[len]);
+ symbol_type = line[len];
len += 2;
symbol_name = line + len;
len = line_len - len;
@@ -480,24 +561,18 @@ int kallsyms__parse(const char *filename, void *arg,
break;
}
- if (prev_symbol_type) {
- u64 end = start;
- if (end != prev_start)
- --end;
- err = process_symbol(arg, prev_symbol_name,
- prev_symbol_type, prev_start, end);
- if (err)
- break;
- }
-
- memcpy(prev_symbol_name, symbol_name, len + 1);
- prev_symbol_type = symbol_type;
- prev_start = start;
+ /*
+ * module symbols are not sorted so we add all
+ * symbols with zero length and rely on
+ * symbols__fixup_end() to fix it up.
+ */
+ err = process_symbol(arg, symbol_name,
+ symbol_type, start, start);
+ if (err)
+ break;
}
- free(prev_symbol_name);
free(line);
-out_close:
fclose(file);
return err;
@@ -703,6 +778,9 @@ int dso__load_kallsyms(struct dso *dso, const char *filename,
if (dso__load_all_kallsyms(dso, filename, map) < 0)
return -1;
+ symbols__fixup_duplicate(&dso->symbols[map->type]);
+ symbols__fixup_end(&dso->symbols[map->type]);
+
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
dso->symtab_type = SYMTAB__GUEST_KALLSYMS;
else
@@ -1092,8 +1170,7 @@ static int dso__load_sym(struct dso *dso, struct map *map, const char *name,
if (dso->has_build_id) {
u8 build_id[BUILD_ID_SIZE];
- if (elf_read_build_id(elf, build_id,
- BUILD_ID_SIZE) != BUILD_ID_SIZE)
+ if (elf_read_build_id(elf, build_id, BUILD_ID_SIZE) < 0)
goto out_elf_end;
if (!dso__build_id_equal(dso, build_id))
@@ -1111,6 +1188,8 @@ static int dso__load_sym(struct dso *dso, struct map *map, const char *name,
}
opdsec = elf_section_by_name(elf, &ehdr, &opdshdr, ".opd", &opdidx);
+ if (opdshdr.sh_type != SHT_PROGBITS)
+ opdsec = NULL;
if (opdsec)
opddata = elf_rawdata(opdsec, NULL);
@@ -1276,6 +1355,7 @@ new_symbol:
* For misannotated, zeroed, ASM function sizes.
*/
if (nr > 0) {
+ symbols__fixup_duplicate(&dso->symbols[map->type]);
symbols__fixup_end(&dso->symbols[map->type]);
if (kmap) {
/*
@@ -1362,8 +1442,8 @@ static int elf_read_build_id(Elf *elf, void *bf, size_t size)
ptr = data->d_buf;
while (ptr < (data->d_buf + data->d_size)) {
GElf_Nhdr *nhdr = ptr;
- int namesz = NOTE_ALIGN(nhdr->n_namesz),
- descsz = NOTE_ALIGN(nhdr->n_descsz);
+ size_t namesz = NOTE_ALIGN(nhdr->n_namesz),
+ descsz = NOTE_ALIGN(nhdr->n_descsz);
const char *name;
ptr += sizeof(*nhdr);
@@ -1372,8 +1452,10 @@ static int elf_read_build_id(Elf *elf, void *bf, size_t size)
if (nhdr->n_type == NT_GNU_BUILD_ID &&
nhdr->n_namesz == sizeof("GNU")) {
if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
- memcpy(bf, ptr, BUILD_ID_SIZE);
- err = BUILD_ID_SIZE;
+ size_t sz = min(size, descsz);
+ memcpy(bf, ptr, sz);
+ memset(bf + sz, 0, size - sz);
+ err = descsz;
break;
}
}
@@ -1425,7 +1507,7 @@ int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
while (1) {
char bf[BUFSIZ];
GElf_Nhdr nhdr;
- int namesz, descsz;
+ size_t namesz, descsz;
if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
break;
@@ -1434,15 +1516,16 @@ int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
descsz = NOTE_ALIGN(nhdr.n_descsz);
if (nhdr.n_type == NT_GNU_BUILD_ID &&
nhdr.n_namesz == sizeof("GNU")) {
- if (read(fd, bf, namesz) != namesz)
+ if (read(fd, bf, namesz) != (ssize_t)namesz)
break;
if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
- if (read(fd, build_id,
- BUILD_ID_SIZE) == BUILD_ID_SIZE) {
+ size_t sz = min(descsz, size);
+ if (read(fd, build_id, sz) == (ssize_t)sz) {
+ memset(build_id + sz, 0, size - sz);
err = 0;
break;
}
- } else if (read(fd, bf, descsz) != descsz)
+ } else if (read(fd, bf, descsz) != (ssize_t)descsz)
break;
} else {
int n = namesz + descsz;
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