perf tools: Always use non inlined file name for 'srcfile' sort key

When profiling the kernel with the 'srcfile' sort key it's common to
"get stuck" in include. For example a lot of code uses current or other
inlines, so they get accounted to some random include file. This is not
very useful as a high level categorization.

For example just profiling the idle loop usually shows mostly inlines,
so you never see the actual cpuidle file.

This patch changes the 'srcfile' sort key to always unwind the inline
stack using BFD/DWARF. So we always account to the base function that
called the inline.

In a few cases include is still shown (for example for MSR accesses),
but that is because they get inlining expanded as part of assigning to a
global function pointer. For the majority it works fine though.

v2: Use simpler while loop. Add maximum iteration count.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1441133239-31254-1-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 291be1d84bc3..09c1a8b7b4c2 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -321,6 +321,8 @@ struct symbol;
 extern bool srcline_full_filename;
 char *get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
 		  bool show_sym);
+char *__get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
+		  bool show_sym, bool unwind_inlines);
 void free_srcline(char *srcline);
 
 int filename__read_str(const char *filename, char **buf, size_t *sizep);