perf hists: Allow for max_stack greater than PERF_MAX_STACK_DEPTH

Use the max_stack value instead of PERF_MAX_STACK_DEPTH so that
arbitrary-sized callchains can be supported.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1443186956-18718-17-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/hist.c

@@ -695,7 +695,7 @@ iter_finish_normal_entry(struct hist_entry_iter *iter,
 }
 
 static int
-iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused,
+iter_prepare_cumulative_entry(struct hist_entry_iter *iter,
 			      struct addr_location *al __maybe_unused)
 {
 	struct hist_entry **he_cache;
@@ -707,7 +707,7 @@ iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused,
 	 * cumulated only one time to prevent entries more than 100%
 	 * overhead.
 	 */
-	he_cache = malloc(sizeof(*he_cache) * (PERF_MAX_STACK_DEPTH + 1));
+	he_cache = malloc(sizeof(*he_cache) * (iter->max_stack + 1));
 	if (he_cache == NULL)
 		return -ENOMEM;
 
@@ -868,6 +868,8 @@ int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
 	if (err)
 		return err;
 
+	iter->max_stack = max_stack_depth;
+
 	err = iter->ops->prepare_entry(iter, al);
 	if (err)
 		goto out;

tools/perf/util/hist.h

@@ -90,6 +90,7 @@ struct hist_entry_iter {
 	int curr;
 
 	bool hide_unresolved;
+	int max_stack;
 
 	struct perf_evsel *evsel;
 	struct perf_sample *sample;