perf hists: Threaded addition and sorting of entries

By using a mutex just for inserting and rotating two hist_entry rb
trees, so that when sorting we can get the last batch of entries created
from the ring buffer, merge it with whatever we have processed so far
and show the output while new entries are being added.

The 'report' tool continues, for now, to do it without threading, but
will use this in the future to allow visualization of results in long
perf.data sessions while the entries are being processed.

The new 'top' tool will be the first user.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-9b05atsn0q6m7fqgrug8fk2i@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/tools/perf/util/sort.h b/tools/perf/util/sort.h
index 77d0388..03851e3 100644
--- a/tools/perf/util/sort.h
+++ b/tools/perf/util/sort.h
@@ -45,6 +45,7 @@ extern enum sort_type sort__first_dimension;
  * @nr_rows - rows expanded in callchain, recalculated on folding/unfolding
  */
 struct hist_entry {
+	struct rb_node		rb_node_in;
 	struct rb_node		rb_node;
 	u64			period;
 	u64			period_sys;