perf hists: Fix formatting of long symbol names

We had a hardcoded buffer for formatting histogram entries, truncating
long symbol names (C++ anyone?).

Fix it by using hists__sort_list_width() before formatting the first
histogram entry to calculate the max lenght needed by traversing the
overheads and columns lists (sort order).

Reported-by: Stephane Eranian <eranian@google.com>
Tested-by: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-vdfkkyfdp8rboh7j9344o3ss@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/ui/stdio/hist.c b/tools/perf/ui/stdio/hist.c
index 5b4fb33..194e2f4 100644 (file)
--- a/tools/perf/ui/stdio/hist.c
+++ b/tools/perf/ui/stdio/hist.c
@@ -350,9 +350,9 @@ static int hist_entry__period_snprintf(struct perf_hpp *hpp,
 }
 
 static int hist_entry__fprintf(struct hist_entry *he, size_t size,
-                              struct hists *hists, FILE *fp)
+                              struct hists *hists,
+                              char *bf, size_t bfsz, FILE *fp)
 {
-       char bf[512];
        int ret;
        struct perf_hpp hpp = {
                .buf            = bf,
@@ -360,8 +360,8 @@ static int hist_entry__fprintf(struct hist_entry *he, size_t size,
        };
        bool color = !symbol_conf.field_sep;
 
-       if (size == 0 || size > sizeof(bf))
-               size = hpp.size = sizeof(bf);
+       if (size == 0 || size > bfsz)
+               size = hpp.size = bfsz;
 
        ret = hist_entry__period_snprintf(&hpp, he, color);
        hist_entry__sort_snprintf(he, bf + ret, size - ret, hists);
@@ -392,6 +392,8 @@ size_t hists__fprintf(struct hists *hists, bool show_header, int max_rows,
                .ptr    = hists_to_evsel(hists),
        };
        bool first = true;
+       size_t linesz;
+       char *line = NULL;
 
        init_rem_hits();
 
@@ -479,6 +481,13 @@ size_t hists__fprintf(struct hists *hists, bool show_header, int max_rows,
                goto out;
 
 print_entries:
+       linesz = hists__sort_list_width(hists) + 3 + 1;
+       line = malloc(linesz);
+       if (line == NULL) {
+               ret = -1;
+               goto out;
+       }
+
        for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
                struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
                float percent = h->stat.period * 100.0 /
@@ -490,10 +499,10 @@ print_entries:
                if (percent < min_pcnt)
                        continue;
 
-               ret += hist_entry__fprintf(h, max_cols, hists, fp);
+               ret += hist_entry__fprintf(h, max_cols, hists, line, linesz, fp);
 
                if (max_rows && ++nr_rows >= max_rows)
-                       goto out;
+                       break;
 
                if (h->ms.map == NULL && verbose > 1) {
                        __map_groups__fprintf_maps(&h->thread->mg,
@@ -501,6 +510,8 @@ print_entries:
                        fprintf(fp, "%.10s end\n", graph_dotted_line);
                }
        }
+
+       free(line);
 out:
        free(rem_sq_bracket);