return self;
 }
 
+/*
+ * When debugging newt problems it was useful to be able to "unroll"
+ * the calls to newtCheckBoxTreeAdd{Array,Item}, so that we can generate
+ * a source file with the sequence of calls to these methods, to then
+ * tweak the arrays to get the intended results, so I'm keeping this code
+ * here, may be useful again in the future.
+ */
+#undef NEWT_DEBUG
+
+static void newt_checkbox_tree__add(newtComponent tree, const char *str,
+                                   void *priv, int *indexes)
+{
+#ifdef NEWT_DEBUG
+       /* Print the newtCheckboxTreeAddArray to tinker with its index arrays */
+       int i = 0, len = 40 - strlen(str);
+
+       fprintf(stderr,
+               "\tnewtCheckboxTreeAddItem(tree, %*.*s\"%s\", (void *)%p, 0, ",
+               len, len, " ", str, priv);
+       while (indexes[i] != NEWT_ARG_LAST) {
+               if (indexes[i] != NEWT_ARG_APPEND)
+                       fprintf(stderr, " %d,", indexes[i]);
+               else
+                       fprintf(stderr, " %s,", "NEWT_ARG_APPEND");
+               ++i;
+       }
+       fprintf(stderr, " %s", " NEWT_ARG_LAST);\n");
+       fflush(stderr);
+#endif
+       newtCheckboxTreeAddArray(tree, str, priv, 0, indexes);
+}
+
+static char *callchain_list__sym_name(struct callchain_list *self,
+                                     char *bf, size_t bfsize)
+{
+       if (self->sym)
+               return self->sym->name;
+
+       snprintf(bf, bfsize, "%#Lx", self->ip);
+       return bf;
+}
+
+static void __callchain__append_graph_browser(struct callchain_node *self,
+                                             newtComponent tree, u64 total,
+                                             int *indexes, int depth)
+{
+       struct rb_node *node;
+       u64 new_total, remaining;
+       int idx = 0;
+
+       if (callchain_param.mode == CHAIN_GRAPH_REL)
+               new_total = self->children_hit;
+       else
+               new_total = total;
+
+       remaining = new_total;
+       node = rb_first(&self->rb_root);
+       while (node) {
+               struct callchain_node *child = rb_entry(node, struct callchain_node, rb_node);
+               struct rb_node *next = rb_next(node);
+               u64 cumul = cumul_hits(child);
+               struct callchain_list *chain;
+               int first = true, printed = 0;
+               int chain_idx = -1;
+               remaining -= cumul;
+
+               indexes[depth] = NEWT_ARG_APPEND;
+               indexes[depth + 1] = NEWT_ARG_LAST;
+
+               list_for_each_entry(chain, &child->val, list) {
+                       char ipstr[BITS_PER_LONG / 4 + 1],
+                            *alloc_str = NULL;
+                       const char *str = callchain_list__sym_name(chain, ipstr, sizeof(ipstr));
+
+                       if (first) {
+                               double percent = cumul * 100.0 / new_total;
+
+                               first = false;
+                               if (asprintf(&alloc_str, "%2.2f%% %s", percent, str) < 0)
+                                       str = "Not enough memory!";
+                               else
+                                       str = alloc_str;
+                       } else {
+                               indexes[depth] = idx;
+                               indexes[depth + 1] = NEWT_ARG_APPEND;
+                               indexes[depth + 2] = NEWT_ARG_LAST;
+                               ++chain_idx;
+                       }
+                       newt_checkbox_tree__add(tree, str, chain->sym, indexes);
+                       free(alloc_str);
+                       ++printed;
+               }
+
+               indexes[depth] = idx;
+               if (chain_idx != -1)
+                       indexes[depth + 1] = chain_idx;
+               if (printed != 0)
+                       ++idx;
+               __callchain__append_graph_browser(child, tree, new_total, indexes,
+                                                 depth + (chain_idx != -1 ? 2 : 1));
+               node = next;
+       }
+}
+
+static void callchain__append_graph_browser(struct callchain_node *self,
+                                           newtComponent tree, u64 total,
+                                           int *indexes, int parent_idx)
+{
+       struct callchain_list *chain;
+       int i = 0;
+
+       indexes[1] = NEWT_ARG_APPEND;
+       indexes[2] = NEWT_ARG_LAST;
+
+       list_for_each_entry(chain, &self->val, list) {
+               char ipstr[BITS_PER_LONG / 4 + 1], *str;
+
+               if (chain->ip >= PERF_CONTEXT_MAX)
+                       continue;
+
+               if (!i++ && sort__first_dimension == SORT_SYM)
+                       continue;
+
+               str = callchain_list__sym_name(chain, ipstr, sizeof(ipstr));
+               newt_checkbox_tree__add(tree, str, chain->sym, indexes);
+       }
+
+       indexes[1] = parent_idx;
+       indexes[2] = NEWT_ARG_APPEND;
+       indexes[3] = NEWT_ARG_LAST;
+       __callchain__append_graph_browser(self, tree, total, indexes, 2);
+}
+
+static void hist_entry__append_callchain_browser(struct hist_entry *self,
+                                                newtComponent tree, u64 total, int parent_idx)
+{
+       struct rb_node *rb_node;
+       int indexes[1024] = { [0] = parent_idx, };
+       int idx = 0;
+       struct callchain_node *chain;
+
+       rb_node = rb_first(&self->sorted_chain);
+       while (rb_node) {
+               chain = rb_entry(rb_node, struct callchain_node, rb_node);
+               switch (callchain_param.mode) {
+               case CHAIN_FLAT:
+                       break;
+               case CHAIN_GRAPH_ABS: /* falldown */
+               case CHAIN_GRAPH_REL:
+                       callchain__append_graph_browser(chain, tree, total, indexes, idx++);
+                       break;
+               case CHAIN_NONE:
+               default:
+                       break;
+               }
+               rb_node = rb_next(rb_node);
+       }
+}
+
+/*
+ * FIXME: get lib/string.c linked with perf somehow
+ */
+static char *skip_spaces(const char *str)
+{
+       while (isspace(*str))
+               ++str;
+       return (char *)str;
+}
+
+static char *strim(char *s)
+{
+       size_t size;
+       char *end;
+
+       s = skip_spaces(s);
+       size = strlen(s);
+       if (!size)
+               return s;
+
+       end = s + size - 1;
+       while (end >= s && isspace(*end))
+               end--;
+       *(end + 1) = '\0';
+
+       return s;
+}
+
 static size_t hist_entry__append_browser(struct hist_entry *self,
-                                        newtComponent listbox, u64 total)
+                                        newtComponent tree, u64 total)
 {
-       char bf[1024];
-       size_t len;
+       char bf[1024], *s;
        FILE *fp;
 
        if (symbol_conf.exclude_other && !self->parent)
        if (fp == NULL)
                return 0;
 
-       len = hist_entry__fprintf(self, NULL, false, 0, fp, total);
-
+       hist_entry__fprintf(self, NULL, false, 0, fp, total);
        fclose(fp);
-       newtListboxAppendEntry(listbox, bf, self);
-       return len;
+
+       /*
+        * FIXME: We shouldn't need to trim, as the printing routines shouldn't
+        * add spaces it in the first place, the stdio output routines should
+        * call a __snprintf method instead of the current __print (that
+        * actually is a __fprintf) one, but get the raw string and _then_ add
+        * the newline, as this is a detail of stdio printing, not needed in
+        * other UIs, e.g. newt.
+        */
+       s = strim(bf);
+
+       if (symbol_conf.use_callchain) {
+               int indexes[2];
+
+               indexes[0] = NEWT_ARG_APPEND;
+               indexes[1] = NEWT_ARG_LAST;
+               newt_checkbox_tree__add(tree, s, self->sym, indexes);
+       } else
+               newtListboxAppendEntry(tree, s, self->sym);
+
+       return strlen(s);
 }
 
-static void hist_entry__annotate_browser(struct hist_entry *self)
+static void symbol__annotate_browser(const struct symbol *self)
 {
        FILE *fp;
        int cols, rows;
-       newtComponent form, listbox;
+       newtComponent form, tree;
        struct newtExitStruct es;
        char *str;
        size_t line_len, max_line_len = 0;
        size_t max_usable_width;
        char *line = NULL;
 
-       if (self->sym == NULL)
+       if (self == NULL)
                return;
 
-       if (asprintf(&str, "perf annotate %s 2>&1 | expand", self->sym->name) < 0)
+       if (asprintf(&str, "perf annotate %s 2>&1 | expand", self->name) < 0)
                return;
 
        fp = popen(str, "r");
 
        newtPushHelpLine("Press ESC to exit");
        newtGetScreenSize(&cols, &rows);
-       listbox = newtListbox(0, 0, rows - 5, NEWT_FLAG_SCROLL);
+       tree = newtListbox(0, 0, rows - 5, NEWT_FLAG_SCROLL);
 
        while (!feof(fp)) {
                if (getline(&line, &line_len, fp) < 0 || !line_len)
 
                if (line_len > max_line_len)
                        max_line_len = line_len;
-               newtListboxAppendEntry(listbox, line, NULL);
+               newtListboxAppendEntry(tree, line, NULL);
        }
        fclose(fp);
        free(line);
        if (max_line_len > max_usable_width)
                max_line_len = max_usable_width;
 
-       newtListboxSetWidth(listbox, max_line_len);
+       newtListboxSetWidth(tree, max_line_len);
 
-       newtCenteredWindow(max_line_len + 2, rows - 5, self->sym->name);
+       newtCenteredWindow(max_line_len + 2, rows - 5, self->name);
        form = newt_form__new();
-       newtFormAddComponents(form, listbox, NULL);
+       newtFormAddComponents(form, tree, NULL);
 
        newtFormRun(form, &es);
        newtFormDestroy(form);
 {
        struct sort_entry *se;
        struct rb_node *nd;
+       char seq[] = ".";
        unsigned int width;
        char *col_width = symbol_conf.col_width_list_str;
-       int rows;
-       size_t max_len = 0;
+       int rows, cols, idx;
+       int max_len = 0;
        char str[1024];
-       newtComponent form, listbox;
+       newtComponent form, tree;
        struct newtExitStruct es;
 
        snprintf(str, sizeof(str), "Samples: %Ld", session_total);
        newtDrawRootText(0, 0, str);
        newtPushHelpLine(helpline);
 
-       newtGetScreenSize(NULL, &rows);
-
-       form = newt_form__new();
+       newtGetScreenSize(&cols, &rows);
 
-       listbox = newtListbox(1, 1, rows - 2, (NEWT_FLAG_SCROLL |
-                                              NEWT_FLAG_BORDER |
-                                              NEWT_FLAG_RETURNEXIT));
+       if (symbol_conf.use_callchain)
+               tree = newtCheckboxTreeMulti(0, 0, rows - 5, seq,
+                                               NEWT_FLAG_SCROLL);
+       else
+               tree = newtListbox(0, 0, rows - 5, (NEWT_FLAG_SCROLL |
+                                                      NEWT_FLAG_RETURNEXIT));
 
        list_for_each_entry(se, &hist_entry__sort_list, list) {
                if (se->elide)
                }
        }
 
+       idx = 0;
        for (nd = rb_first(hists); nd; nd = rb_next(nd)) {
                struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
-               size_t len = hist_entry__append_browser(h, listbox, session_total);
+               int len = hist_entry__append_browser(h, tree, session_total);
                if (len > max_len)
                        max_len = len;
+               if (symbol_conf.use_callchain) {
+                       hist_entry__append_callchain_browser(h, tree, session_total, idx++);
+                       if (idx > 3300)
+                               break;
+               }
        }
 
-       newtListboxSetWidth(listbox, max_len);
-       newtFormAddComponents(form, listbox, NULL);
+       if (max_len > cols)
+               max_len = cols - 3;
+
+       if (!symbol_conf.use_callchain)
+               newtListboxSetWidth(tree, max_len);
+
+       newtCenteredWindow(max_len + (symbol_conf.use_callchain ? 5 : 0),
+                          rows - 5, "Report");
+       form = newt_form__new();
+       newtFormAddHotKey(form, 'A');
+       newtFormAddHotKey(form, 'a');
+       newtFormAddComponents(form, tree, NULL);
 
        while (1) {
-               struct hist_entry *selection;
+               const struct symbol *selection;
 
                newtFormRun(form, &es);
-               if (es.reason == NEWT_EXIT_HOTKEY)
+               if (es.reason == NEWT_EXIT_HOTKEY &&
+                   toupper(es.u.key) != 'A')
                        break;
-               selection = newtListboxGetCurrent(listbox);
-               hist_entry__annotate_browser(selection);
+               if (!symbol_conf.use_callchain)
+                       selection = newtListboxGetCurrent(tree);
+               else
+                       selection = newtCheckboxTreeGetCurrent(tree);
+               symbol__annotate_browser(selection);
        }
 
        newtFormDestroy(form);
+       newtPopWindow();
 }
 
 static char browser__last_msg[1024];