perf tools: Improve message about missing symtabs for deleted DSOs

Instead of:

  no symbols found in /usr/lib/gstreamer-0.10/libgsttypefindfunctions.so (deleted), maybe install a debug package?
  no symbols found in /usr/lib/gstreamer-0.10/libgstaudioconvert.so (deleted), maybe install a debug package?

We now emit:

  /usr/lib/gstreamer-0.10/libgsttypefindfunctions.so was updated, restart the long running apps that use it!
  /usr/lib/gstreamer-0.10/libgstaudioconvert.so was updated, restart the long running apps that use it!

Which is far less misleading about what the cause of the
symbol mismatch is.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256927305-4628-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 14 insertions, 2 deletions

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index 679011c1b6d1..f1e216955420 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -75,6 +75,8 @@ out_delete:
         return NULL;
 }
 
+#define DSO__DELETED "(deleted)"
+
 struct symbol *
 map__find_symbol(struct map *self, u64 ip, symbol_filter_t filter)
 {
@@ -86,8 +88,18 @@ map__find_symbol(struct map *self, u64 ip, symbol_filter_t filter)
                                    self->dso->long_name);
                         return NULL;
                 } else if (nr == 0) {
-                        pr_warning("No symbols found in %s, maybe install a debug package?\n",
-                                   self->dso->long_name);
+                        const char *name = self->dso->long_name;
+                        const size_t len = strlen(name);
+                        const size_t real_len = len - sizeof(DSO__DELETED);
+
+                        if (len > sizeof(DSO__DELETED) &&
+                            strcmp(name + real_len + 1, DSO__DELETED) == 0)
+                                pr_warning("%.*s was updated, restart the "
+                                           "long running apps that use it!\n",
+                                           real_len, name);
+                        else
+                                pr_warning("no symbols found in %s, maybe "
+                                           "install a debug package?\n", name);
                         return NULL;
                 }
         }