perf top: Fix -z option behavior

The current -z option does almost nothing.  It doesn't zero the existing
samples so that we can see profiles of exited process after last
refresh.  It seems it only affects annotation.

This patch clears existing entries before processing if -z option is
given.  For this original decaying logic also moved before processing.

Reported-by: Stephane Eranian <eranian@google.com>
Tested-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1407831366-28892-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 17 insertions, 6 deletions

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 4b0e15c2b2a8..87a6615a40fa 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -276,11 +276,17 @@ static void perf_top__print_sym_table(struct perf_top *top)
                 return;
         }
 
+        if (top->zero) {
+                hists__delete_entries(&top->sym_evsel->hists);
+        } else {
+                hists__decay_entries(&top->sym_evsel->hists,
+                                     top->hide_user_symbols,
+                                     top->hide_kernel_symbols);
+        }
+
         hists__collapse_resort(&top->sym_evsel->hists, NULL);
         hists__output_resort(&top->sym_evsel->hists);
-        hists__decay_entries(&top->sym_evsel->hists,
-                             top->hide_user_symbols,
-                             top->hide_kernel_symbols);
+
         hists__output_recalc_col_len(&top->sym_evsel->hists,
                                      top->print_entries - printed);
         putchar('\n');
@@ -542,11 +548,16 @@ static void perf_top__sort_new_samples(void *arg)
         if (t->evlist->selected != NULL)
                 t->sym_evsel = t->evlist->selected;
 
+        if (t->zero) {
+                hists__delete_entries(&t->sym_evsel->hists);
+        } else {
+                hists__decay_entries(&t->sym_evsel->hists,
+                                     t->hide_user_symbols,
+                                     t->hide_kernel_symbols);
+        }
+
         hists__collapse_resort(&t->sym_evsel->hists, NULL);
         hists__output_resort(&t->sym_evsel->hists);
-        hists__decay_entries(&t->sym_evsel->hists,
-                             t->hide_user_symbols,
-                             t->hide_kernel_symbols);
 }
 
 static void *display_thread_tui(void *arg)