perf symbols: Improve debugging information about symtab origins

Be more clear about DSO long names and tell from which file
kernel symbols were obtained, all in --verbose mode:

    [root@mica ~]# perf report -v > /dev/null
    Looking at the vmlinux_path (5 entries long)
    Using /lib/modules/2.6.33-rc8-tip-00777-g0918527-dirty/build/vmlinux for symbols
    [root@mica ~]# mv /lib/modules/2.6.33-rc8-tip-00777-g0918527-dirty/build/vmlinux /tmp/dd
    [root@mica ~]# perf report -v > /dev/null
    Looking at the vmlinux_path (5 entries long)
    Using /proc/kallsyms for symbols
    [root@mica ~]#

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1266866139-6361-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

4 files changed, 21 insertions, 7 deletions

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index 138e3cb2b727..e509cd59c67d 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -5,6 +5,11 @@
 #include <stdio.h>
 #include "debug.h"
 
+const char *map_type__name[MAP__NR_TYPES] = {
+        [MAP__FUNCTION] = "Functions",
+        [MAP__VARIABLE] = "Variables",
+};
+
 static inline int is_anon_memory(const char *filename)
 {
         return strcmp(filename, "//anon") == 0;
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index 86f77cb1d060..b756368076c6 100644
--- a/tools/perf/util/map.h
+++ b/tools/perf/util/map.h
@@ -13,6 +13,8 @@ enum map_type {
 
 #define MAP__NR_TYPES (MAP__VARIABLE + 1)
 
+extern const char *map_type__name[MAP__NR_TYPES];
+
 struct dso;
 struct ref_reloc_sym;
 struct map_groups;
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 320b15178e95..7aab4e5f3669 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -367,6 +367,10 @@ size_t dso__fprintf(struct dso *self, enum map_type type, FILE *fp)
         struct rb_node *nd;
         size_t ret = fprintf(fp, "dso: %s (", self->short_name);
 
+        if (self->short_name != self->long_name)
+                ret += fprintf(fp, "%s, ", self->long_name);
+        ret += fprintf(fp, "%s, %sloaded, ", map_type__name[type],
+                       self->loaded ? "" : "NOT ");
         ret += dso__fprintf_buildid(self, fp);
         ret += fprintf(fp, ")\n");
         for (nd = rb_first(&self->symbols[type]); nd; nd = rb_next(nd)) {
@@ -1580,6 +1584,9 @@ static int dso__load_vmlinux(struct dso *self, struct map *map,
         err = dso__load_sym(self, map, vmlinux, fd, filter, 0);
         close(fd);
 
+        if (err > 0)
+                pr_debug("Using %s for symbols\n", vmlinux);
+
         return err;
 }
 
@@ -1594,7 +1601,6 @@ int dso__load_vmlinux_path(struct dso *self, struct map *map,
         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
                 err = dso__load_vmlinux(self, map, vmlinux_path[i], filter);
                 if (err > 0) {
-                        pr_debug("Using %s for symbols\n", vmlinux_path[i]);
                         dso__set_long_name(self, strdup(vmlinux_path[i]));
                         break;
                 }
@@ -1661,12 +1667,16 @@ static int dso__load_kernel_sym(struct dso *self, struct map *map,
 
                 if (asprintf(&kallsyms_allocated_filename,
                              "%s/.debug/[kernel.kallsyms]/%s",
-                             getenv("HOME"), sbuild_id) == -1)
+                             getenv("HOME"), sbuild_id) == -1) {
+                        pr_err("Not enough memory for kallsyms file lookup\n");
                         return -1;
+                }
 
                 kallsyms_filename = kallsyms_allocated_filename;
 
                 if (access(kallsyms_filename, F_OK)) {
+                        pr_err("No kallsyms or vmlinux with build-id %s "
+                               "was found\n", sbuild_id);
                         free(kallsyms_allocated_filename);
                         return -1;
                 }
@@ -1680,6 +1690,8 @@ static int dso__load_kernel_sym(struct dso *self, struct map *map,
 
 do_kallsyms:
         err = dso__load_kallsyms(self, kallsyms_filename, map, filter);
+        if (err > 0)
+                pr_debug("Using %s for symbols\n", kallsyms_filename);
         free(kallsyms_allocated_filename);
 
 out_try_fixup:
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index 9e8995eaf2b6..c090654cb6c0 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -53,11 +53,6 @@ int thread__comm_len(struct thread *self)
         return self->comm_len;
 }
 
-static const char *map_type__name[MAP__NR_TYPES] = {
-        [MAP__FUNCTION] = "Functions",
-        [MAP__VARIABLE] = "Variables",
-};
-
 static size_t __map_groups__fprintf_maps(struct map_groups *self,
                                          enum map_type type, FILE *fp)
 {