perf top: Remove redundant perf_top->sym_counter

We can get that counter index from perf_top->sym_evsel->idx instead.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-top.c

@@ -515,24 +515,25 @@ static void handle_keypress(struct perf_session *session, int c)
 			break;
 		case 'E':
 			if (top.evlist->nr_entries > 1) {
+				int counter;
 				fprintf(stderr, "\nAvailable events:");
 
 				list_for_each_entry(top.sym_evsel, &top.evlist->entries, node)
 					fprintf(stderr, "\n\t%d %s", top.sym_evsel->idx, event_name(top.sym_evsel));
 
-				prompt_integer(&top.sym_counter, "Enter details event counter");
+				prompt_integer(&counter, "Enter details event counter");
 
-				if (top.sym_counter >= top.evlist->nr_entries) {
+				if (counter >= top.evlist->nr_entries) {
 					top.sym_evsel = list_entry(top.evlist->entries.next, struct perf_evsel, node);
-					top.sym_counter = 0;
 					fprintf(stderr, "Sorry, no such event, using %s.\n", event_name(top.sym_evsel));
 					sleep(1);
 					break;
 				}
 				list_for_each_entry(top.sym_evsel, &top.evlist->entries, node)
-					if (top.sym_evsel->idx == top.sym_counter)
+					if (top.sym_evsel->idx == counter)
 						break;
-			} else top.sym_counter = 0;
+			} else
+				top.sym_evsel = list_entry(top.evlist->entries.next, struct perf_evsel, node);
 			break;
 		case 'f':
 			prompt_integer(&top.count_filter, "Enter display event count filter");

tools/perf/util/top.c

@@ -171,7 +171,7 @@ float perf_top__decay_samples(struct perf_top *top, struct rb_root *root)
 {
 	struct sym_entry *syme, *n;
 	float sum_ksamples = 0.0;
-	int snap = !top->display_weighted ? top->sym_counter : 0, j;
+	int snap = !top->display_weighted ? top->sym_evsel->idx : 0, j;
 
 	/* Sort the active symbols */
 	pthread_mutex_lock(&top->active_symbols_lock);

tools/perf/util/top.h

@@ -41,7 +41,7 @@ struct perf_top {
 	u64		   exact_samples;
 	u64		   guest_us_samples, guest_kernel_samples;
 	int		   print_entries, count_filter, delay_secs;
-	int		   display_weighted, freq, rb_entries, sym_counter;
+	int		   display_weighted, freq, rb_entries;
 	pid_t		   target_pid, target_tid;
 	bool		   hide_kernel_symbols, hide_user_symbols, zero;
 	const char	   *cpu_list;