perf stream: Use evsel rather than evsel->idx

An evsel idx may not be stable due to sorting, evlist removal,
etc. Avoid use of the idx where the evsel itself can be used to avoid
these problems.

Reviewed-by: James Clark <[e-mail]>
Reviewed-by: Namhyung Kim <[e-mail]>
Signed-off-by: Ian Rogers <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Ahelenia Ziemiańska <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Cc: Chen Ni <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Kan Liang <[e-mail]>
Cc: Mark Rutland <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/builtin-diff.c

···
 			continue;
 
 		es_base = evsel_streams__entry(data_base->evlist_streams,
-					       evsel_base->core.idx);
+					       evsel_base);
 		if (!es_base)
 			return -1;
 
 		es_pair = evsel_streams__entry(data_pair->evlist_streams,
-					       evsel_pair->core.idx);
+					       evsel_pair);
 		if (!es_pair)
 			return -1;
 

tools/perf/util/stream.c

···
 			goto err;
 
 		s->nr_streams_max = nr_streams_max;
-		s->evsel_idx = -1;
 	}
 
 	els->ev_streams = es;
···
 
 		hists__output_resort(hists, NULL);
 		init_hot_callchain(hists, &es[i]);
-		es[i].evsel_idx = pos->core.idx;
+		es[i].evsel = pos;
 		i++;
 	}
 
···
 }
 
 struct evsel_streams *evsel_streams__entry(struct evlist_streams *els,
-					   int evsel_idx)
+					   const struct evsel *evsel)
 {
 	struct evsel_streams *es = els->ev_streams;
 
 	for (int i = 0; i < els->nr_evsel; i++) {
-		if (es[i].evsel_idx == evsel_idx)
+		if (es[i].evsel == evsel)
 			return &es[i];
 	}
 

tools/perf/util/stream.h

···
 #ifndef __PERF_STREAM_H
 #define __PERF_STREAM_H
 
-#include "callchain.h"
+struct callchain_node;
+struct evlist;
+struct evsel;
 
 struct stream {
 	struct callchain_node	*cnode;
···
 
 struct evsel_streams {
 	struct stream		*streams;
+	const struct evsel	*evsel;
 	int			nr_streams_max;
 	int			nr_streams;
-	int			evsel_idx;
 	u64			streams_hits;
 };
 
···
 	int			nr_evsel;
 };
 
-struct evlist;
-
 void evlist_streams__delete(struct evlist_streams *els);
 
 struct evlist_streams *evlist__create_streams(struct evlist *evlist,
 					      int nr_streams_max);
 
 struct evsel_streams *evsel_streams__entry(struct evlist_streams *els,
-					   int evsel_idx);
+					   const struct evsel *evsel);
 
 void evsel_streams__match(struct evsel_streams *es_base,
 			  struct evsel_streams *es_pair);