perf tools: Add ->unmap_ip operation to struct map

We need this because we get section relative addresses when
reading the symtabs, but when a tool like 'perf annotate' needs
to match these address to what 'objdump -dS' produces we need
the address + section back again.

So in annotate now we look at the 'struct hist_entry' instances
(that weren't really being used) so that we iterate only over
the symbols that had some hit and get the map where that
particular hit happened so that we can get the right address to
match with annotate.

Verified that at least:

 perf annotate mmap_read_counter # Uses the ~/bin/perf binary
 perf annotate --vmlinux /home/acme/git/build/perf/vmlinux intel_pmu_enable_all

on a 'perf record perf top' session seems to work.

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: <1255979877-12533-1-git-send-email-acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index c2e62be..6b5be56 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -82,6 +82,7 @@
 	u64			end;
 	u64			pgoff;
 	u64			(*map_ip)(struct map *, u64);
+	u64			(*unmap_ip)(struct map *, u64);
 	struct dso		*dso;
 };
 
@@ -90,7 +91,12 @@
 	return ip - map->start + map->pgoff;
 }
 
-static inline u64 vdso__map_ip(struct map *map __used, u64 ip)
+static inline u64 map__unmap_ip(struct map *map, u64 ip)
+{
+	return ip + map->start - map->pgoff;
+}
+
+static inline u64 identity__map_ip(struct map *map __used, u64 ip)
 {
 	return ip;
 }