Re: [PATCH 16/35] perf annotate: Add samples into struct annotation_line

[Ravi Bangoria]

Hi Jiri,

This patch seems to be causing segfault with "perf top --stdio".
Steps to reproduce:
1. start "perf top --stdio" in one terminal
2. run some simple workload in another terminal, let it get finished.
3. annotate function from previous workload in perf top (press 'a' 
followed by 's')

Perf will crash with:

  perf: Segmentation fault
  Obtained 8 stack frames.
  ./perf(sighandler_dump_stack+0x3e) [0x4f1b6e]
  /lib64/libc.so.6(+0x36a7f) [0x7ff3aa7e4a7f]
  ./perf() [0x4a27fd]
  ./perf(symbol__annotate+0x199) [0x4a4439]
  ./perf() [0x44e32d]
  ./perf() [0x44f098]
  /lib64/libpthread.so.0(+0x736c) [0x7ff3acee836c]
  /lib64/libc.so.6(clone+0x3e) [0x7ff3aa8bee1e]

Can you please check.

Thanks,
Ravi


On 10/11/2017 08:31 PM, Jiri Olsa wrote:
Adding samples array into struct annotation_line to
hold the annotation data. The data are populated in
the following patches.

Link: http://lkml.kernel.org/n/tip-97yja5m7z9brrcuf2gwr5...@git.kernel.org
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
  tools/perf/util/annotate.c |  8 ++++++++
  tools/perf/util/annotate.h | 17 ++++++++++++-----
  2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 8e1e88aab45a..1b5c7d0a53e8 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -901,7 +901,14 @@ static struct annotation_line*
  annotation_line__new(struct annotate_args *args, size_t privsize)
  {
        struct annotation_line *al;
+       struct perf_evsel *evsel = args->evsel;
        size_t size = privsize + sizeof(*al);
+       int nr = 1;
+
+       if (perf_evsel__is_group_event(evsel))
+               nr = evsel->nr_members;
+
+       size += sizeof(al->samples[0]) * nr;

        al = zalloc(size);
        if (al) {
@@ -910,6 +917,7 @@ annotation_line__new(struct annotate_args *args, size_t 
privsize)
                al->offset     = args->offset;
                al->line       = strdup(args->line);
                al->line_nr    = args->line_nr;
+               al->samples_nr = nr;
        }

        return al;
diff --git a/tools/perf/util/annotate.h b/tools/perf/util/annotate.h
index a02a2bf4f2ab..9c722a7e5f6d 100644
--- a/tools/perf/util/annotate.h
+++ b/tools/perf/util/annotate.h
@@ -58,6 +58,16 @@ bool ins__is_fused(struct arch *arch, const char *ins1, 
const char *ins2);

  struct annotation;

+struct sym_hist_entry {
+       u64             nr_samples;
+       u64             period;
+};
+
+struct annotation_data {
+       double                   percent;
+       struct sym_hist_entry    he;
+};
+
  struct annotation_line {
        struct list_head         node;
        struct rb_node           rb_node;
@@ -67,6 +77,8 @@ struct annotation_line {
        float                    ipc;
        u64                      cycles;
        size_t                   privsize;
+       int                      samples_nr;
+       struct annotation_data   samples[0];
  };

  struct disasm_line {
@@ -87,11 +99,6 @@ static inline bool disasm_line__has_offset(const struct 
disasm_line *dl)
        return dl->ops.target.offset_avail;
  }

-struct sym_hist_entry {
-       u64             nr_samples;
-       u64             period;
-};
-
  void disasm_line__free(struct disasm_line *dl);
  struct annotation_line*
  annotation_line__next(struct annotation_line *pos, struct list_head *head);