diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
index 17465d454a0e..f76b1a9d5a6e 100644
--- a/tools/lib/perf/evlist.c
+++ b/tools/lib/perf/evlist.c
@@ -571,7 +571,6 @@ int perf_evlist__mmap_ops(struct perf_evlist *evlist,
 {
 	struct perf_evsel *evsel;
 	const struct perf_cpu_map *cpus = evlist->cpus;
-	const struct perf_thread_map *threads = evlist->threads;
 
 	if (!ops || !ops->get || !ops->mmap)
 		return -EINVAL;
@@ -583,7 +582,7 @@ int perf_evlist__mmap_ops(struct perf_evlist *evlist,
 	perf_evlist__for_each_entry(evlist, evsel) {
 		if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
 		    evsel->sample_id == NULL &&
-		    perf_evsel__alloc_id(evsel, perf_cpu_map__nr(cpus), threads->nr) < 0)
+		    perf_evsel__alloc_id(evsel, evsel->fd->max_x, evsel->fd->max_y) < 0)
 			return -ENOMEM;
 	}