simpleperf: check monitored targets regularly.

When monitoring some threads/processes not forked by simpleperf,
check if these threads/processes exist regularly. So we can
stop profiling once all threads/processes exit.

Also handle SIGHUP signal, so we can finish profiling properly
when `adb shell simpleperf record xxx` is killed by Ctrl-C.

Add corresponding tests.

Bug: http://b/33558210
Test: run simpleperf_unit_test.
Change-Id: Ieae4d00d099dc1c7a0c51b0610dff43981bb642e

1 files changed, 24 insertions, 0 deletions

diff --git a/simpleperf/cmd_record_test.cpp b/simpleperf/cmd_record_test.cpp
index 35f330ef..28e2e9b1 100644
--- a/simpleperf/cmd_record_test.cpp
+++ b/simpleperf/cmd_record_test.cpp
@@ -18,9 +18,11 @@
 
 #include <android-base/stringprintf.h>
 #include <android-base/test_utils.h>
+#include <sys/syscall.h>
 
 #include <map>
 #include <memory>
+#include <thread>
 
 #include "command.h"
 #include "environment.h"
@@ -335,3 +337,25 @@ TEST(record_cmd, support_modifier_for_clock_events) {
     }
   }
 }
+
+TEST(record_cmd, handle_SIGHUP) {
+  TemporaryFile tmpfile;
+  std::thread thread([]() {
+    sleep(1);
+    kill(getpid(), SIGHUP);
+  });
+  thread.detach();
+  ASSERT_TRUE(RecordCmd()->Run({"-o", tmpfile.path, "sleep", "1000000"}));
+}
+
+TEST(record_cmd, stop_when_no_more_targets) {
+  TemporaryFile tmpfile;
+  std::atomic<int> tid(0);
+  std::thread thread([&]() {
+    tid = syscall(__NR_gettid);
+    sleep(1);
+  });
+  thread.detach();
+  while (tid == 0);
+  ASSERT_TRUE(RecordCmd()->Run({"-o", tmpfile.path, "-t", std::to_string(tid)}));
+}