[PATCH/RFC 09/16] perf tools: Update hist entry's hists pointer

[Namhyung Kim <namhyung@kernel.org>]

When sample is processed using multi-thread, each sample is gathered on
each thread's hist tree and then merged into the real hist tree.  But
hist_entry->hists pointer was not updated so it could refer wrong hists
resulted in missing outputs.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/hist.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index ea4f3ad978b0..a12e5022fe04 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -1008,6 +1008,14 @@ bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
 	}
 	hists->nr_entries++;
 
+	/*
+	 * If a hist entry is processed in multi-threaded environment,
+	 * it points to a dummy local hists which was used only for
+	 * intermidate processing.  So update it to a real one so that
+	 * it can find the correct info later.
+	 */
+	he->hists = hists;
+
 	rb_link_node(&he->rb_node_in, parent, p);
 	rb_insert_color(&he->rb_node_in, root);
 	return true;
-- 
2.6.2