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-rw-r--r--tools/perf/builtin-report.c397
-rw-r--r--tools/perf/util/hist.c384
-rw-r--r--tools/perf/util/hist.h1
3 files changed, 385 insertions, 397 deletions
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 26f4de6d9a51..24d20e7d125a 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -43,316 +43,6 @@ static char *pretty_printing_style = default_pretty_printing_style;
static char callchain_default_opt[] = "fractal,0.5";
-static size_t
-callchain__fprintf_left_margin(FILE *fp, int left_margin)
-{
- int i;
- int ret;
-
- ret = fprintf(fp, " ");
-
- for (i = 0; i < left_margin; i++)
- ret += fprintf(fp, " ");
-
- return ret;
-}
-
-static size_t ipchain__fprintf_graph_line(FILE *fp, int depth, int depth_mask,
- int left_margin)
-{
- int i;
- size_t ret = 0;
-
- ret += callchain__fprintf_left_margin(fp, left_margin);
-
- for (i = 0; i < depth; i++)
- if (depth_mask & (1 << i))
- ret += fprintf(fp, "| ");
- else
- ret += fprintf(fp, " ");
-
- ret += fprintf(fp, "\n");
-
- return ret;
-}
-static size_t
-ipchain__fprintf_graph(FILE *fp, struct callchain_list *chain, int depth,
- int depth_mask, int count, u64 total_samples,
- int hits, int left_margin)
-{
- int i;
- size_t ret = 0;
-
- ret += callchain__fprintf_left_margin(fp, left_margin);
- for (i = 0; i < depth; i++) {
- if (depth_mask & (1 << i))
- ret += fprintf(fp, "|");
- else
- ret += fprintf(fp, " ");
- if (!count && i == depth - 1) {
- double percent;
-
- percent = hits * 100.0 / total_samples;
- ret += percent_color_fprintf(fp, "--%2.2f%%-- ", percent);
- } else
- ret += fprintf(fp, "%s", " ");
- }
- if (chain->sym)
- ret += fprintf(fp, "%s\n", chain->sym->name);
- else
- ret += fprintf(fp, "%p\n", (void *)(long)chain->ip);
-
- return ret;
-}
-
-static struct symbol *rem_sq_bracket;
-static struct callchain_list rem_hits;
-
-static void init_rem_hits(void)
-{
- rem_sq_bracket = malloc(sizeof(*rem_sq_bracket) + 6);
- if (!rem_sq_bracket) {
- fprintf(stderr, "Not enough memory to display remaining hits\n");
- return;
- }
-
- strcpy(rem_sq_bracket->name, "[...]");
- rem_hits.sym = rem_sq_bracket;
-}
-
-static size_t
-__callchain__fprintf_graph(FILE *fp, struct callchain_node *self,
- u64 total_samples, int depth, int depth_mask,
- int left_margin)
-{
- struct rb_node *node, *next;
- struct callchain_node *child;
- struct callchain_list *chain;
- int new_depth_mask = depth_mask;
- u64 new_total;
- u64 remaining;
- size_t ret = 0;
- int i;
-
- if (callchain_param.mode == CHAIN_GRAPH_REL)
- new_total = self->children_hit;
- else
- new_total = total_samples;
-
- remaining = new_total;
-
- node = rb_first(&self->rb_root);
- while (node) {
- u64 cumul;
-
- child = rb_entry(node, struct callchain_node, rb_node);
- cumul = cumul_hits(child);
- remaining -= cumul;
-
- /*
- * The depth mask manages the output of pipes that show
- * the depth. We don't want to keep the pipes of the current
- * level for the last child of this depth.
- * Except if we have remaining filtered hits. They will
- * supersede the last child
- */
- next = rb_next(node);
- if (!next && (callchain_param.mode != CHAIN_GRAPH_REL || !remaining))
- new_depth_mask &= ~(1 << (depth - 1));
-
- /*
- * But we keep the older depth mask for the line seperator
- * to keep the level link until we reach the last child
- */
- ret += ipchain__fprintf_graph_line(fp, depth, depth_mask,
- left_margin);
- i = 0;
- list_for_each_entry(chain, &child->val, list) {
- if (chain->ip >= PERF_CONTEXT_MAX)
- continue;
- ret += ipchain__fprintf_graph(fp, chain, depth,
- new_depth_mask, i++,
- new_total,
- cumul,
- left_margin);
- }
- ret += __callchain__fprintf_graph(fp, child, new_total,
- depth + 1,
- new_depth_mask | (1 << depth),
- left_margin);
- node = next;
- }
-
- if (callchain_param.mode == CHAIN_GRAPH_REL &&
- remaining && remaining != new_total) {
-
- if (!rem_sq_bracket)
- return ret;
-
- new_depth_mask &= ~(1 << (depth - 1));
-
- ret += ipchain__fprintf_graph(fp, &rem_hits, depth,
- new_depth_mask, 0, new_total,
- remaining, left_margin);
- }
-
- return ret;
-}
-
-
-static size_t
-callchain__fprintf_graph(FILE *fp, struct callchain_node *self,
- u64 total_samples, int left_margin)
-{
- struct callchain_list *chain;
- bool printed = false;
- int i = 0;
- int ret = 0;
-
- list_for_each_entry(chain, &self->val, list) {
- if (chain->ip >= PERF_CONTEXT_MAX)
- continue;
-
- if (!i++ && sort__first_dimension == SORT_SYM)
- continue;
-
- if (!printed) {
- ret += callchain__fprintf_left_margin(fp, left_margin);
- ret += fprintf(fp, "|\n");
- ret += callchain__fprintf_left_margin(fp, left_margin);
- ret += fprintf(fp, "---");
-
- left_margin += 3;
- printed = true;
- } else
- ret += callchain__fprintf_left_margin(fp, left_margin);
-
- if (chain->sym)
- ret += fprintf(fp, " %s\n", chain->sym->name);
- else
- ret += fprintf(fp, " %p\n", (void *)(long)chain->ip);
- }
-
- ret += __callchain__fprintf_graph(fp, self, total_samples, 1, 1, left_margin);
-
- return ret;
-}
-
-static size_t
-callchain__fprintf_flat(FILE *fp, struct callchain_node *self,
- u64 total_samples)
-{
- struct callchain_list *chain;
- size_t ret = 0;
-
- if (!self)
- return 0;
-
- ret += callchain__fprintf_flat(fp, self->parent, total_samples);
-
-
- list_for_each_entry(chain, &self->val, list) {
- if (chain->ip >= PERF_CONTEXT_MAX)
- continue;
- if (chain->sym)
- ret += fprintf(fp, " %s\n", chain->sym->name);
- else
- ret += fprintf(fp, " %p\n",
- (void *)(long)chain->ip);
- }
-
- return ret;
-}
-
-static size_t
-hist_entry_callchain__fprintf(FILE *fp, struct hist_entry *self,
- u64 total_samples, int left_margin)
-{
- struct rb_node *rb_node;
- struct callchain_node *chain;
- size_t ret = 0;
-
- rb_node = rb_first(&self->sorted_chain);
- while (rb_node) {
- double percent;
-
- chain = rb_entry(rb_node, struct callchain_node, rb_node);
- percent = chain->hit * 100.0 / total_samples;
- switch (callchain_param.mode) {
- case CHAIN_FLAT:
- ret += percent_color_fprintf(fp, " %6.2f%%\n",
- percent);
- ret += callchain__fprintf_flat(fp, chain, total_samples);
- break;
- case CHAIN_GRAPH_ABS: /* Falldown */
- case CHAIN_GRAPH_REL:
- ret += callchain__fprintf_graph(fp, chain, total_samples,
- left_margin);
- case CHAIN_NONE:
- default:
- break;
- }
- ret += fprintf(fp, "\n");
- rb_node = rb_next(rb_node);
- }
-
- return ret;
-}
-
-static size_t hist_entry__fprintf(FILE *fp, struct hist_entry *self,
- struct perf_session *session)
-{
- struct sort_entry *se;
- size_t ret;
-
- if (symbol_conf.exclude_other && !self->parent)
- return 0;
-
- if (session->events_stats.total)
- ret = percent_color_fprintf(fp,
- symbol_conf.field_sep ? "%.2f" : " %6.2f%%",
- (self->count * 100.0) / session->events_stats.total);
- else
- ret = fprintf(fp, symbol_conf.field_sep ? "%lld" : "%12lld ", self->count);
-
- if (symbol_conf.show_nr_samples) {
- if (symbol_conf.field_sep)
- fprintf(fp, "%c%lld", *symbol_conf.field_sep, self->count);
- else
- fprintf(fp, "%11lld", self->count);
- }
-
- list_for_each_entry(se, &hist_entry__sort_list, list) {
- if (se->elide)
- continue;
-
- fprintf(fp, "%s", symbol_conf.field_sep ?: " ");
- ret += se->print(fp, self, se->width ? *se->width : 0);
- }
-
- ret += fprintf(fp, "\n");
-
- if (symbol_conf.use_callchain) {
- int left_margin = 0;
-
- if (sort__first_dimension == SORT_COMM) {
- se = list_first_entry(&hist_entry__sort_list, typeof(*se),
- list);
- left_margin = se->width ? *se->width : 0;
- left_margin -= thread__comm_len(self->thread);
- }
-
- hist_entry_callchain__fprintf(fp, self, session->events_stats.total,
- left_margin);
- }
-
- return ret;
-}
-
-/*
- * collect histogram counts
- */
-
static int perf_session__add_hist_entry(struct perf_session *self,
struct addr_location *al,
struct ip_callchain *chain, u64 count)
@@ -381,93 +71,6 @@ static int perf_session__add_hist_entry(struct perf_session *self,
return 0;
}
-static size_t perf_session__fprintf_hists(struct perf_session *self, FILE *fp)
-{
- struct hist_entry *pos;
- struct sort_entry *se;
- struct rb_node *nd;
- size_t ret = 0;
- unsigned int width;
- char *col_width = symbol_conf.col_width_list_str;
-
- init_rem_hits();
-
- fprintf(fp, "# Samples: %ld\n", self->events_stats.total);
- fprintf(fp, "#\n");
-
- fprintf(fp, "# Overhead");
- if (symbol_conf.show_nr_samples) {
- if (symbol_conf.field_sep)
- fprintf(fp, "%cSamples", *symbol_conf.field_sep);
- else
- fputs(" Samples ", fp);
- }
- list_for_each_entry(se, &hist_entry__sort_list, list) {
- if (se->elide)
- continue;
- if (symbol_conf.field_sep) {
- fprintf(fp, "%c%s", *symbol_conf.field_sep, se->header);
- continue;
- }
- width = strlen(se->header);
- if (se->width) {
- if (symbol_conf.col_width_list_str) {
- if (col_width) {
- *se->width = atoi(col_width);
- col_width = strchr(col_width, ',');
- if (col_width)
- ++col_width;
- }
- }
- width = *se->width = max(*se->width, width);
- }
- fprintf(fp, " %*s", width, se->header);
- }
- fprintf(fp, "\n");
-
- if (symbol_conf.field_sep)
- goto print_entries;
-
- fprintf(fp, "# ........");
- if (symbol_conf.show_nr_samples)
- fprintf(fp, " ..........");
- list_for_each_entry(se, &hist_entry__sort_list, list) {
- unsigned int i;
-
- if (se->elide)
- continue;
-
- fprintf(fp, " ");
- if (se->width)
- width = *se->width;
- else
- width = strlen(se->header);
- for (i = 0; i < width; i++)
- fprintf(fp, ".");
- }
- fprintf(fp, "\n");
-
- fprintf(fp, "#\n");
-
-print_entries:
- for (nd = rb_first(&self->hists); nd; nd = rb_next(nd)) {
- pos = rb_entry(nd, struct hist_entry, rb_node);
- ret += hist_entry__fprintf(fp, pos, self);
- }
-
- if (sort_order == default_sort_order &&
- parent_pattern == default_parent_pattern) {
- fprintf(fp, "#\n");
- fprintf(fp, "# (For a higher level overview, try: perf report --sort comm,dso)\n");
- fprintf(fp, "#\n");
- }
- fprintf(fp, "\n");
-
- free(rem_sq_bracket);
-
- return ret;
-}
-
static int validate_chain(struct ip_callchain *chain, event_t *event)
{
unsigned int chain_size;
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index d9a5a19391dc..270eb8f3dcee 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -206,3 +206,387 @@ void perf_session__output_resort(struct perf_session *self, u64 total_samples)
self->hists = tmp;
}
+
+static size_t callchain__fprintf_left_margin(FILE *fp, int left_margin)
+{
+ int i;
+ int ret = fprintf(fp, " ");
+
+ for (i = 0; i < left_margin; i++)
+ ret += fprintf(fp, " ");
+
+ return ret;
+}
+
+static size_t ipchain__fprintf_graph_line(FILE *fp, int depth, int depth_mask,
+ int left_margin)
+{
+ int i;
+ size_t ret = callchain__fprintf_left_margin(fp, left_margin);
+
+ for (i = 0; i < depth; i++)
+ if (depth_mask & (1 << i))
+ ret += fprintf(fp, "| ");
+ else
+ ret += fprintf(fp, " ");
+
+ ret += fprintf(fp, "\n");
+
+ return ret;
+}
+
+static size_t ipchain__fprintf_graph(FILE *fp, struct callchain_list *chain,
+ int depth, int depth_mask, int count,
+ u64 total_samples, int hits,
+ int left_margin)
+{
+ int i;
+ size_t ret = 0;
+
+ ret += callchain__fprintf_left_margin(fp, left_margin);
+ for (i = 0; i < depth; i++) {
+ if (depth_mask & (1 << i))
+ ret += fprintf(fp, "|");
+ else
+ ret += fprintf(fp, " ");
+ if (!count && i == depth - 1) {
+ double percent;
+
+ percent = hits * 100.0 / total_samples;
+ ret += percent_color_fprintf(fp, "--%2.2f%%-- ", percent);
+ } else
+ ret += fprintf(fp, "%s", " ");
+ }
+ if (chain->sym)
+ ret += fprintf(fp, "%s\n", chain->sym->name);
+ else
+ ret += fprintf(fp, "%p\n", (void *)(long)chain->ip);
+
+ return ret;
+}
+
+static struct symbol *rem_sq_bracket;
+static struct callchain_list rem_hits;
+
+static void init_rem_hits(void)
+{
+ rem_sq_bracket = malloc(sizeof(*rem_sq_bracket) + 6);
+ if (!rem_sq_bracket) {
+ fprintf(stderr, "Not enough memory to display remaining hits\n");
+ return;
+ }
+
+ strcpy(rem_sq_bracket->name, "[...]");
+ rem_hits.sym = rem_sq_bracket;
+}
+
+static size_t __callchain__fprintf_graph(FILE *fp, struct callchain_node *self,
+ u64 total_samples, int depth,
+ int depth_mask, int left_margin)
+{
+ struct rb_node *node, *next;
+ struct callchain_node *child;
+ struct callchain_list *chain;
+ int new_depth_mask = depth_mask;
+ u64 new_total;
+ u64 remaining;
+ size_t ret = 0;
+ int i;
+
+ if (callchain_param.mode == CHAIN_GRAPH_REL)
+ new_total = self->children_hit;
+ else
+ new_total = total_samples;
+
+ remaining = new_total;
+
+ node = rb_first(&self->rb_root);
+ while (node) {
+ u64 cumul;
+
+ child = rb_entry(node, struct callchain_node, rb_node);
+ cumul = cumul_hits(child);
+ remaining -= cumul;
+
+ /*
+ * The depth mask manages the output of pipes that show
+ * the depth. We don't want to keep the pipes of the current
+ * level for the last child of this depth.
+ * Except if we have remaining filtered hits. They will
+ * supersede the last child
+ */
+ next = rb_next(node);
+ if (!next && (callchain_param.mode != CHAIN_GRAPH_REL || !remaining))
+ new_depth_mask &= ~(1 << (depth - 1));
+
+ /*
+ * But we keep the older depth mask for the line seperator
+ * to keep the level link until we reach the last child
+ */
+ ret += ipchain__fprintf_graph_line(fp, depth, depth_mask,
+ left_margin);
+ i = 0;
+ list_for_each_entry(chain, &child->val, list) {
+ if (chain->ip >= PERF_CONTEXT_MAX)
+ continue;
+ ret += ipchain__fprintf_graph(fp, chain, depth,
+ new_depth_mask, i++,
+ new_total,
+ cumul,
+ left_margin);
+ }
+ ret += __callchain__fprintf_graph(fp, child, new_total,
+ depth + 1,
+ new_depth_mask | (1 << depth),
+ left_margin);
+ node = next;
+ }
+
+ if (callchain_param.mode == CHAIN_GRAPH_REL &&
+ remaining && remaining != new_total) {
+
+ if (!rem_sq_bracket)
+ return ret;
+
+ new_depth_mask &= ~(1 << (depth - 1));
+
+ ret += ipchain__fprintf_graph(fp, &rem_hits, depth,
+ new_depth_mask, 0, new_total,
+ remaining, left_margin);
+ }
+
+ return ret;
+}
+
+static size_t callchain__fprintf_graph(FILE *fp, struct callchain_node *self,
+ u64 total_samples, int left_margin)
+{
+ struct callchain_list *chain;
+ bool printed = false;
+ int i = 0;
+ int ret = 0;
+
+ list_for_each_entry(chain, &self->val, list) {
+ if (chain->ip >= PERF_CONTEXT_MAX)
+ continue;
+
+ if (!i++ && sort__first_dimension == SORT_SYM)
+ continue;
+
+ if (!printed) {
+ ret += callchain__fprintf_left_margin(fp, left_margin);
+ ret += fprintf(fp, "|\n");
+ ret += callchain__fprintf_left_margin(fp, left_margin);
+ ret += fprintf(fp, "---");
+
+ left_margin += 3;
+ printed = true;
+ } else
+ ret += callchain__fprintf_left_margin(fp, left_margin);
+
+ if (chain->sym)
+ ret += fprintf(fp, " %s\n", chain->sym->name);
+ else
+ ret += fprintf(fp, " %p\n", (void *)(long)chain->ip);
+ }
+
+ ret += __callchain__fprintf_graph(fp, self, total_samples, 1, 1, left_margin);
+
+ return ret;
+}
+
+static size_t callchain__fprintf_flat(FILE *fp, struct callchain_node *self,
+ u64 total_samples)
+{
+ struct callchain_list *chain;
+ size_t ret = 0;
+
+ if (!self)
+ return 0;
+
+ ret += callchain__fprintf_flat(fp, self->parent, total_samples);
+
+
+ list_for_each_entry(chain, &self->val, list) {
+ if (chain->ip >= PERF_CONTEXT_MAX)
+ continue;
+ if (chain->sym)
+ ret += fprintf(fp, " %s\n", chain->sym->name);
+ else
+ ret += fprintf(fp, " %p\n",
+ (void *)(long)chain->ip);
+ }
+
+ return ret;
+}
+
+static size_t hist_entry_callchain__fprintf(FILE *fp, struct hist_entry *self,
+ u64 total_samples, int left_margin)
+{
+ struct rb_node *rb_node;
+ struct callchain_node *chain;
+ size_t ret = 0;
+
+ rb_node = rb_first(&self->sorted_chain);
+ while (rb_node) {
+ double percent;
+
+ chain = rb_entry(rb_node, struct callchain_node, rb_node);
+ percent = chain->hit * 100.0 / total_samples;
+ switch (callchain_param.mode) {
+ case CHAIN_FLAT:
+ ret += percent_color_fprintf(fp, " %6.2f%%\n",
+ percent);
+ ret += callchain__fprintf_flat(fp, chain, total_samples);
+ break;
+ case CHAIN_GRAPH_ABS: /* Falldown */
+ case CHAIN_GRAPH_REL:
+ ret += callchain__fprintf_graph(fp, chain, total_samples,
+ left_margin);
+ case CHAIN_NONE:
+ default:
+ break;
+ }
+ ret += fprintf(fp, "\n");
+ rb_node = rb_next(rb_node);
+ }
+
+ return ret;
+}
+
+static size_t hist_entry__fprintf(FILE *fp, struct hist_entry *self,
+ struct perf_session *session)
+{
+ struct sort_entry *se;
+ size_t ret;
+
+ if (symbol_conf.exclude_other && !self->parent)
+ return 0;
+
+ if (session->events_stats.total)
+ ret = percent_color_fprintf(fp,
+ symbol_conf.field_sep ? "%.2f" : " %6.2f%%",
+ (self->count * 100.0) / session->events_stats.total);
+ else
+ ret = fprintf(fp, symbol_conf.field_sep ? "%lld" : "%12lld ", self->count);
+
+ if (symbol_conf.show_nr_samples) {
+ if (symbol_conf.field_sep)
+ fprintf(fp, "%c%lld", *symbol_conf.field_sep, self->count);
+ else
+ fprintf(fp, "%11lld", self->count);
+ }
+
+ list_for_each_entry(se, &hist_entry__sort_list, list) {
+ if (se->elide)
+ continue;
+
+ fprintf(fp, "%s", symbol_conf.field_sep ?: " ");
+ ret += se->print(fp, self, se->width ? *se->width : 0);
+ }
+
+ ret += fprintf(fp, "\n");
+
+ if (symbol_conf.use_callchain) {
+ int left_margin = 0;
+
+ if (sort__first_dimension == SORT_COMM) {
+ se = list_first_entry(&hist_entry__sort_list, typeof(*se),
+ list);
+ left_margin = se->width ? *se->width : 0;
+ left_margin -= thread__comm_len(self->thread);
+ }
+
+ hist_entry_callchain__fprintf(fp, self, session->events_stats.total,
+ left_margin);
+ }
+
+ return ret;
+}
+
+size_t perf_session__fprintf_hists(struct perf_session *self, FILE *fp)
+{
+ struct hist_entry *pos;
+ struct sort_entry *se;
+ struct rb_node *nd;
+ size_t ret = 0;
+ unsigned int width;
+ char *col_width = symbol_conf.col_width_list_str;
+
+ init_rem_hits();
+
+ fprintf(fp, "# Samples: %ld\n", self->events_stats.total);
+ fprintf(fp, "#\n");
+
+ fprintf(fp, "# Overhead");
+ if (symbol_conf.show_nr_samples) {
+ if (symbol_conf.field_sep)
+ fprintf(fp, "%cSamples", *symbol_conf.field_sep);
+ else
+ fputs(" Samples ", fp);
+ }
+ list_for_each_entry(se, &hist_entry__sort_list, list) {
+ if (se->elide)
+ continue;
+ if (symbol_conf.field_sep) {
+ fprintf(fp, "%c%s", *symbol_conf.field_sep, se->header);
+ continue;
+ }
+ width = strlen(se->header);
+ if (se->width) {
+ if (symbol_conf.col_width_list_str) {
+ if (col_width) {
+ *se->width = atoi(col_width);
+ col_width = strchr(col_width, ',');
+ if (col_width)
+ ++col_width;
+ }
+ }
+ width = *se->width = max(*se->width, width);
+ }
+ fprintf(fp, " %*s", width, se->header);
+ }
+ fprintf(fp, "\n");
+
+ if (symbol_conf.field_sep)
+ goto print_entries;
+
+ fprintf(fp, "# ........");
+ if (symbol_conf.show_nr_samples)
+ fprintf(fp, " ..........");
+ list_for_each_entry(se, &hist_entry__sort_list, list) {
+ unsigned int i;
+
+ if (se->elide)
+ continue;
+
+ fprintf(fp, " ");
+ if (se->width)
+ width = *se->width;
+ else
+ width = strlen(se->header);
+ for (i = 0; i < width; i++)
+ fprintf(fp, ".");
+ }
+ fprintf(fp, "\n");
+
+ fprintf(fp, "#\n");
+
+print_entries:
+ for (nd = rb_first(&self->hists); nd; nd = rb_next(nd)) {
+ pos = rb_entry(nd, struct hist_entry, rb_node);
+ ret += hist_entry__fprintf(fp, pos, self);
+ }
+
+ if (sort_order == default_sort_order &&
+ parent_pattern == default_parent_pattern) {
+ fprintf(fp, "#\n");
+ fprintf(fp, "# (For a higher level overview, try: perf report --sort comm,dso)\n");
+ fprintf(fp, "#\n");
+ }
+ fprintf(fp, "\n");
+
+ free(rem_sq_bracket);
+
+ return ret;
+}
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index 7efdb1b6d8c8..c7ac78d93b0c 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -21,5 +21,6 @@ void hist_entry__free(struct hist_entry *);
void perf_session__output_resort(struct perf_session *self, u64 total_samples);
void perf_session__collapse_resort(struct perf_session *self);
+size_t perf_session__fprintf_hists(struct perf_session *self, FILE *fp);
#endif /* __PERF_HIST_H */