[PATCH -tip v2 2/6] perf script: add magic word to indicate the failure of resolving symbols

Akihiro Nagai
2011-07-17T09:30:24Z

Latest perf-script doesn't output symbol name when it failed to
resolve symbol name. This output is not friendly for external scripts
because it causes misaligment. So, this patch adds the magic word
"(unknown)" when perf-script failed to resolve symbols.

At the same time, this patch changes perf-script to output "[unknown]"
in the DSO field, when it failed to resolve the path of DSOs.

Changes in v2:
- add this patch

Signed-off-by: Akihiro Nagai <akihiro.nagai.hw@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---

tools/perf/builtin-script.c | 18 +++++-------------
tools/perf/util/map.c | 12 ++++++++++++
tools/perf/util/map.h | 1 +
tools/perf/util/session.c | 35 ++++++++++-------------------------
tools/perf/util/symbol.c | 12 ++++++++++++
tools/perf/util/symbol.h | 1 +
6 files changed, 41 insertions(+), 38 deletions(-)

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 09024ec..b3e0951 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -320,7 +320,6 @@ static void print_sample_addr(union perf_event *event,
{
struct addr_location al;
u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
- const char *symname, *dsoname;

printf("%16" PRIx64, sample->addr);

@@ -340,21 +339,14 @@ static void print_sample_addr(union perf_event *event,
al.sym = map__find_symbol(al.map, al.addr, NULL);

if (PRINT_FIELD(SYM)) {
- if (al.sym && al.sym->name)
- symname = al.sym->name;
- else
- symname = "";
-
- printf(" %16s", symname);
+ printf(" ");
+ symbol__print_symname(al.sym);
}

if (PRINT_FIELD(DSO)) {
- if (al.map && al.map->dso && al.map->dso->name)
- dsoname = al.map->dso->name;
- else
- dsoname = "";
-
- printf(" (%s)", dsoname);
+ printf(" (");
+ map__print_dsoname(al.map);
+ printf(")");
}
}

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index a16ecab..dddc0f3 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -200,6 +200,18 @@ size_t map__fprintf(struct map *self, FILE *fp)
self->start, self->end, self->pgoff, self->dso->name);
}

+void map__print_dsoname(struct map *self)
+{
+ const char *dsoname;
+
+ if (self && self->dso && self->dso->name)
+ dsoname = self->dso->name;
+ else
+ dsoname = "[unknown]";
+
+ printf("%s", dsoname);
+}
+
/*
* objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
* map->dso->adjust_symbols==1 for ET_EXEC-like cases.
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index b397c03..6f452b9 100644
--- a/tools/perf/util/map.h
+++ b/tools/perf/util/map.h
@@ -112,6 +112,7 @@ void map__delete(struct map *self);
struct map *map__clone(struct map *self);
int map__overlap(struct map *l, struct map *r);
size_t map__fprintf(struct map *self, FILE *fp);
+void map__print_dsoname(struct map *self);

int map__load(struct map *self, symbol_filter_t filter);
struct symbol *map__find_symbol(struct map *self,
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 453a010..442be3a 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1214,7 +1214,6 @@ void perf_session__print_ip(union perf_event *event,
int print_sym, int print_dso)
{
struct addr_location al;
- const char *symname, *dsoname;
struct callchain_cursor *cursor = &session->callchain_cursor;
struct callchain_cursor_node *node;

@@ -1242,20 +1241,13 @@ void perf_session__print_ip(union perf_event *event,

printf("\t%16" PRIx64, node->ip);
if (print_sym) {
- if (node->sym && node->sym->name)
- symname = node->sym->name;
- else
- symname = "";
-
- printf(" %s", symname);
+ printf(" ");
+ symbol__print_symname(node->sym);
}
if (print_dso) {
- if (node->map && node->map->dso && node->map->dso->name)
- dsoname = node->map->dso->name;
- else
- dsoname = "";
-
- printf(" (%s)", dsoname);
+ printf(" (");
+ map__print_dsoname(al.map);
+ printf(")");
}
printf("\n");

@@ -1265,21 +1257,14 @@ void perf_session__print_ip(union perf_event *event,
} else {
printf("%16" PRIx64, sample->ip);
if (print_sym) {
- if (al.sym && al.sym->name)
- symname = al.sym->name;
- else
- symname = "";
-
- printf(" %s", symname);
+ printf(" ");
+ symbol__print_symname(al.sym);
}

if (print_dso) {
- if (al.map && al.map->dso && al.map->dso->name)
- dsoname = al.map->dso->name;
- else
- dsoname = "";
-
- printf(" (%s)", dsoname);
+ printf(" (");
+ map__print_dsoname(al.map);
+ printf(")");
}
}
}
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index eec1963..85e19c4 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -175,6 +175,18 @@ static size_t symbol__fprintf(struct symbol *sym, FILE *fp)
sym->name);
}

+void symbol__print_symname(const struct symbol *sym)
+{
+ const char *symname;
+
+ if (sym && sym->name)
+ symname = sym->name;
+ else
+ symname = "(unknown)";
+
+ printf("%s", symname);
+}
+
void dso__set_long_name(struct dso *dso, char *name)
{
if (name == NULL)
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 325ee36..1ec17b4 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -238,6 +238,7 @@ void machines__destroy_guest_kernel_maps(struct rb_root *machines);

int symbol__init(void);
void symbol__exit(void);
+void symbol__print_symname(const struct symbol *sym);
bool symbol_type__is_a(char symbol_type, enum map_type map_type);

size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp);