perf trace: Add pagefault statistics

'perf trace' can show summary of events using -S option. This commit
also reports number of major/minor pagefault events in this summary.

$ perf trace -s --pf all -- sleep 1

 Summary of events:

 sleep (18604), 275 events, 99.6%, 197 minfaults, 0.000 msec

   syscall            calls      min       avg       max      stddev
                               (msec)    (msec)    (msec)        (%)
   --------------- -------- --------- --------- ---------     ------
   read                   2     0.000     0.001     0.002    100.00%
   open                   3     0.004     0.005     0.007     21.13%
   close                  3     0.001     0.001     0.001      1.37%
   fstat                  3     0.001     0.002     0.002     10.66%
   mmap                   8     0.002     0.004     0.006     10.69%
   mprotect               4     0.003     0.005     0.008     24.68%
   munmap                 1     0.005     0.005     0.005      0.00%
   brk                    3     0.001     0.002     0.003     28.08%
   access                 3     0.002     0.003     0.005     24.48%
   nanosleep              1  1000.747  1000.747  1000.747      0.00%
   execve                 8     0.000     0.033     0.246     91.00%
   arch_prctl             1     0.001     0.001     0.001      0.00%

Signed-off-by: Stanislav Fomichev <stfomichev@yandex-team.ru>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1404842716-19190-1-git-send-email-stfomichev@yandex-team.ru
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index dc7a694..b94dffc 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -1133,6 +1133,7 @@
 	u64		  exit_time;
 	bool		  entry_pending;
 	unsigned long	  nr_events;
+	unsigned long	  pfmaj, pfmin;
 	char		  *entry_str;
 	double		  runtime_ms;
 	struct {
@@ -1804,8 +1805,20 @@
 	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
 	struct addr_location al;
 	char map_type = 'd';
+	struct thread_trace *ttrace;
 
 	thread = machine__findnew_thread(trace->host, sample->pid, sample->tid);
+	ttrace = thread__trace(thread, trace->output);
+	if (ttrace == NULL)
+		return -1;
+
+	if (evsel->attr.config == PERF_COUNT_SW_PAGE_FAULTS_MAJ)
+		ttrace->pfmaj++;
+	else
+		ttrace->pfmin++;
+
+	if (trace->summary_only)
+		return 0;
 
 	thread__find_addr_location(thread, trace->host, cpumode, MAP__FUNCTION,
 			      sample->ip, &al);
@@ -2346,6 +2359,10 @@
 	printed += fprintf(fp, " %s (%d), ", thread__comm_str(thread), thread->tid);
 	printed += fprintf(fp, "%lu events, ", ttrace->nr_events);
 	printed += fprintf(fp, "%.1f%%", ratio);
+	if (ttrace->pfmaj)
+		printed += fprintf(fp, ", %lu majfaults", ttrace->pfmaj);
+	if (ttrace->pfmin)
+		printed += fprintf(fp, ", %lu minfaults", ttrace->pfmin);
 	printed += fprintf(fp, ", %.3f msec\n", ttrace->runtime_ms);
 	printed += thread__dump_stats(ttrace, trace, fp);