[tip:perf/urgent] perf report: Do not drop last inlined frame

[tip-bot for Milian Wolff <tipbot@zytor.com>]

Commit-ID:  4d53b9d546f9f4505e6e3d58c8eed894d6f684e7
Gitweb:     http://git.kernel.org/tip/4d53b9d546f9f4505e6e3d58c8eed894d6f684e7
Author:     Milian Wolff <milian.wolff@kdab.com>
AuthorDate: Wed, 24 May 2017 15:21:28 +0900
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Wed, 24 May 2017 08:41:48 +0200

perf report: Do not drop last inlined frame

The very last inlined frame, i.e. the one furthest away from the
non-inlined frame, was silently dropped. This is apparent when
comparing the output of `perf script` and `addr2line`:

~~~~~~
  $ perf script --inline
  ...
  a.out 26722 80836.309329:      72425 cycles:
                     21561 __hypot_finite (/usr/lib/libm-2.25.so)
                      ace3 hypot (/usr/lib/libm-2.25.so)
                       a4a main (a.out)
                           std::abs<double>
                           std::_Norm_helper<true>::_S_do_it<double>
                           std::norm<double>
                           main
                     20510 __libc_start_main (/usr/lib/libc-2.25.so)
                       bd9 _start (a.out)

  $ addr2line -a -f -i -e /tmp/a.out a4a | c++filt
  0x0000000000000a4a
  std::__complex_abs(doublecomplex )
  /usr/include/c++/6.3.1/complex:589
  double std::abs<double>(std::complex<double> const&)
  /usr/include/c++/6.3.1/complex:597
  double std::_Norm_helper<true>::_S_do_it<double>(std::complex<double> const&)
  /usr/include/c++/6.3.1/complex:654
  double std::norm<double>(std::complex<double> const&)
  /usr/include/c++/6.3.1/complex:664
  main
  /tmp/inlining.cpp:14
~~~~~

Note how `std::__complex_abs` is missing from the `perf script`
output. This is similarly showing up in `perf report`. The patch
here fixes this issue, and the output becomes:

~~~~~
  a.out 26722 80836.309329:      72425 cycles:
                     21561 __hypot_finite (/usr/lib/libm-2.25.so)
                      ace3 hypot (/usr/lib/libm-2.25.so)
                       a4a main (a.out)
                           std::__complex_abs
                           std::abs<double>
                           std::_Norm_helper<true>::_S_do_it<double>
                           std::norm<double>
                           main
                     20510 __libc_start_main (/usr/lib/libc-2.25.so)
                       bd9 _start (a.out)
~~~~~

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-7-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 tools/perf/util/srcline.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
index 6af0364..ebc88a7 100644
--- a/tools/perf/util/srcline.c
+++ b/tools/perf/util/srcline.c
@@ -203,6 +203,16 @@ static void addr2line_cleanup(struct a2l_data *a2l)
 
 #define MAX_INLINE_NEST 1024
 
+static int inline_list__append_dso_a2l(struct dso *dso,
+				       struct inline_node *node)
+{
+	struct a2l_data *a2l = dso->a2l;
+	char *funcname = a2l->funcname ? strdup(a2l->funcname) : NULL;
+	char *filename = a2l->filename ? strdup(a2l->filename) : NULL;
+
+	return inline_list__append(filename, funcname, a2l->line, node, dso);
+}
+
 static int addr2line(const char *dso_name, u64 addr,
 		     char **file, unsigned int *line, struct dso *dso,
 		     bool unwind_inlines, struct inline_node *node)
@@ -231,15 +241,15 @@ static int addr2line(const char *dso_name, u64 addr,
 	if (unwind_inlines) {
 		int cnt = 0;
 
+		if (node && inline_list__append_dso_a2l(dso, node))
+			return 0;
+
 		while (bfd_find_inliner_info(a2l->abfd, &a2l->filename,
 					     &a2l->funcname, &a2l->line) &&
 		       cnt++ < MAX_INLINE_NEST) {
 
 			if (node != NULL) {
-				if (inline_list__append(strdup(a2l->filename),
-							strdup(a2l->funcname),
-							a2l->line, node,
-							dso) != 0)
+				if (inline_list__append_dso_a2l(dso, node))
 					return 0;
 				// found at least one inline frame
 				ret = 1;