perf record: Implement control commands handling

Implement handling of 'enable' and 'disable' control commands coming
from control file descriptor.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/f0fde590-1320-dca1-39ff-da3322704d3b@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 1dc8166..739601e 100644 (file)
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1564,6 +1564,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
        bool disabled = false, draining = false;
        int fd;
        float ratio = 0;
+       enum evlist_ctl_cmd cmd = EVLIST_CTL_CMD_UNSUPPORTED;
 
        atexit(record__sig_exit);
        signal(SIGCHLD, sig_handler);
@@ -1883,6 +1884,21 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
                                draining = true;
                }
 
+               if (evlist__ctlfd_process(rec->evlist, &cmd) > 0) {
+                       switch (cmd) {
+                       case EVLIST_CTL_CMD_ENABLE:
+                               pr_info(EVLIST_ENABLED_MSG);
+                               break;
+                       case EVLIST_CTL_CMD_DISABLE:
+                               pr_info(EVLIST_DISABLED_MSG);
+                               break;
+                       case EVLIST_CTL_CMD_ACK:
+                       case EVLIST_CTL_CMD_UNSUPPORTED:
+                       default:
+                               break;
+                       }
+               }
+
                /*
                 * When perf is starting the traced process, at the end events
                 * die with the process and we wait for that. Thus no need to