-f::
 --fields::
         Comma separated list of fields to print. Options are:
-        comm, tid, pid, time, cpu, event, trace, ip, sym, dso, addr, symoff, srcline.
+        comm, tid, pid, time, cpu, event, trace, ip, sym, dso, addr, symoff, srcline, period.
         Field list can be prepended with the type, trace, sw or hw,
         to indicate to which event type the field list applies.
         e.g., -f sw:comm,tid,time,ip,sym  and -f trace:time,cpu,trace
 
        PERF_OUTPUT_ADDR            = 1U << 10,
        PERF_OUTPUT_SYMOFFSET       = 1U << 11,
        PERF_OUTPUT_SRCLINE         = 1U << 12,
+       PERF_OUTPUT_PERIOD          = 1U << 13,
 };
 
 struct output_option {
        {.str = "addr",  .field = PERF_OUTPUT_ADDR},
        {.str = "symoff", .field = PERF_OUTPUT_SYMOFFSET},
        {.str = "srcline", .field = PERF_OUTPUT_SRCLINE},
+       {.str = "period", .field = PERF_OUTPUT_PERIOD},
 };
 
 /* default set to maintain compatibility with current format */
                                        PERF_OUTPUT_CPU))
                return -EINVAL;
 
+       if (PRINT_FIELD(PERIOD) &&
+               perf_evsel__check_stype(evsel, PERF_SAMPLE_PERIOD, "PERIOD",
+                                       PERF_OUTPUT_PERIOD))
+               return -EINVAL;
+
        return 0;
 }
 
 
        print_sample_start(sample, thread, evsel);
 
+       if (PRINT_FIELD(PERIOD))
+               printf("%10" PRIu64 " ", sample->period);
+
        if (PRINT_FIELD(EVNAME)) {
                const char *evname = perf_evsel__name(evsel);
                printf("%s: ", evname ? evname : "[unknown]");
                     "comma separated output fields prepend with 'type:'. "
                     "Valid types: hw,sw,trace,raw. "
                     "Fields: comm,tid,pid,time,cpu,event,trace,ip,sym,dso,"
-                    "addr,symoff", parse_output_fields),
+                    "addr,symoff,period", parse_output_fields),
        OPT_BOOLEAN('a', "all-cpus", &system_wide,
                    "system-wide collection from all CPUs"),
        OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",