perf hists: Introduce hist_entry__init function

Move the 'struct hist_entry' initialization code to a separate function.
It'll be useful and more clear for the following patches that introduce
allocation callbacks.

Releasing the hist_entry object in hist_entry__new function
(where it's allocated) rather than in hist_entry__init.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1467701765-26194-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/hist.c

@@ -352,86 +352,93 @@ void hists__delete_entries(struct hists *hists)
  * histogram, sorted on item, collects periods
  */
 
-static struct hist_entry *hist_entry__new(struct hist_entry *template,
-					  bool sample_self)
-{
-	size_t callchain_size = 0;
-	struct hist_entry *he;
+static int hist_entry__init(struct hist_entry *he,
+			    struct hist_entry *template,
+			    bool sample_self)
+{
+	*he = *template;
+
+	if (symbol_conf.cumulate_callchain) {
+		he->stat_acc = malloc(sizeof(he->stat));
+		if (he->stat_acc == NULL)
+			return -ENOMEM;
+		memcpy(he->stat_acc, &he->stat, sizeof(he->stat));
+		if (!sample_self)
+			memset(&he->stat, 0, sizeof(he->stat));
+	}
 
-	if (symbol_conf.use_callchain)
-		callchain_size = sizeof(struct callchain_root);
+	map__get(he->ms.map);
 
-	he = zalloc(sizeof(*he) + callchain_size);
+	if (he->branch_info) {
+		/*
+		 * This branch info is (a part of) allocated from
+		 * sample__resolve_bstack() and will be freed after
+		 * adding new entries.  So we need to save a copy.
+		 */
+		he->branch_info = malloc(sizeof(*he->branch_info));
+		if (he->branch_info == NULL) {
+			map__zput(he->ms.map);
+			free(he->stat_acc);
+			return -ENOMEM;
+		}
 
-	if (he != NULL) {
-		*he = *template;
+		memcpy(he->branch_info, template->branch_info,
+		       sizeof(*he->branch_info));
 
-		if (symbol_conf.cumulate_callchain) {
-			he->stat_acc = malloc(sizeof(he->stat));
-			if (he->stat_acc == NULL) {
-				free(he);
-				return NULL;
-			}
-			memcpy(he->stat_acc, &he->stat, sizeof(he->stat));
-			if (!sample_self)
-				memset(&he->stat, 0, sizeof(he->stat));
-		}
+		map__get(he->branch_info->from.map);
+		map__get(he->branch_info->to.map);
+	}
 
-		map__get(he->ms.map);
+	if (he->mem_info) {
+		map__get(he->mem_info->iaddr.map);
+		map__get(he->mem_info->daddr.map);
+	}
 
-		if (he->branch_info) {
-			/*
-			 * This branch info is (a part of) allocated from
-			 * sample__resolve_bstack() and will be freed after
-			 * adding new entries.  So we need to save a copy.
-			 */
-			he->branch_info = malloc(sizeof(*he->branch_info));
-			if (he->branch_info == NULL) {
-				map__zput(he->ms.map);
-				free(he->stat_acc);
-				free(he);
-				return NULL;
-			}
+	if (symbol_conf.use_callchain)
+		callchain_init(he->callchain);
 
-			memcpy(he->branch_info, template->branch_info,
-			       sizeof(*he->branch_info));
+	if (he->raw_data) {
+		he->raw_data = memdup(he->raw_data, he->raw_size);
 
-			map__get(he->branch_info->from.map);
-			map__get(he->branch_info->to.map);
+		if (he->raw_data == NULL) {
+			map__put(he->ms.map);
+			if (he->branch_info) {
+				map__put(he->branch_info->from.map);
+				map__put(he->branch_info->to.map);
+				free(he->branch_info);
+			}
+			if (he->mem_info) {
+				map__put(he->mem_info->iaddr.map);
+				map__put(he->mem_info->daddr.map);
+			}
+			free(he->stat_acc);
+			return -ENOMEM;
 		}
+	}
+	INIT_LIST_HEAD(&he->pairs.node);
+	thread__get(he->thread);
 
-		if (he->mem_info) {
-			map__get(he->mem_info->iaddr.map);
-			map__get(he->mem_info->daddr.map);
-		}
+	if (!symbol_conf.report_hierarchy)
+		he->leaf = true;
 
-		if (symbol_conf.use_callchain)
-			callchain_init(he->callchain);
+	return 0;
+}
 
-		if (he->raw_data) {
-			he->raw_data = memdup(he->raw_data, he->raw_size);
+static struct hist_entry *hist_entry__new(struct hist_entry *template,
+					  bool sample_self)
+{
+	size_t callchain_size = 0;
+	struct hist_entry *he;
+	int err = 0;
 
-			if (he->raw_data == NULL) {
-				map__put(he->ms.map);
-				if (he->branch_info) {
-					map__put(he->branch_info->from.map);
-					map__put(he->branch_info->to.map);
-					free(he->branch_info);
-				}
-				if (he->mem_info) {
-					map__put(he->mem_info->iaddr.map);
-					map__put(he->mem_info->daddr.map);
-				}
-				free(he->stat_acc);
-				free(he);
-				return NULL;
-			}
-		}
-		INIT_LIST_HEAD(&he->pairs.node);
-		thread__get(he->thread);
+	if (symbol_conf.use_callchain)
+		callchain_size = sizeof(struct callchain_root);
 
-		if (!symbol_conf.report_hierarchy)
-			he->leaf = true;
+	he = zalloc(sizeof(*he) + callchain_size);
+	if (he) {
+		err = hist_entry__init(he, template, sample_self);
+		if (err)
+			zfree(&he);
 	}
 
 	return he;