2 files changed, 134 insertions, 1 deletions
diff --git a/lldb/packages/Python/lldbsuite/pre_kill_hook/tests/test_darwin.py b/lldb/packages/Python/lldbsuite/pre_kill_hook/tests/test_darwin.py
index 48d286c909e..810b364b07c 100644
--- a/lldb/packages/Python/lldbsuite/pre_kill_hook/tests/test_darwin.py
+++ b/lldb/packages/Python/lldbsuite/pre_kill_hook/tests/test_darwin.py
@@ -38,7 +38,7 @@ class DarwinPreKillTestCase(TestCase):
             print("parent: sending shut-down request to child")
         if self.process:
             self.child_work_queue.put("hello, child")
-        self.process.join()
+            self.process.join()
         if self.verbose:
             print("parent: child is fully shut down")
 
diff --git a/lldb/packages/Python/lldbsuite/pre_kill_hook/tests/test_linux.py b/lldb/packages/Python/lldbsuite/pre_kill_hook/tests/test_linux.py
new file mode 100644
index 00000000000..ab989df0d20
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/pre_kill_hook/tests/test_linux.py
@@ -0,0 +1,133 @@
+"""Test the pre-kill hook on Linux."""
+from __future__ import print_function
+
+# system imports
+from multiprocessing import Process, Queue
+import platform
+import re
+import subprocess
+from unittest import main, TestCase
+
+# third party
+from six import StringIO
+
+
+def do_child_thread():
+    import os
+    x = 0
+    while True:
+        x = x + 42 * os.getpid()
+    return x
+
+
+def do_child_process(child_work_queue, parent_work_queue, verbose):
+    import os
+
+    pid = os.getpid()
+    if verbose:
+        print("child: pid {} started, sending to parent".format(pid))
+    parent_work_queue.put(pid)
+
+    # Spin up a daemon thread to do some "work", which will show
+    # up in a sample of this process.
+    import threading
+    worker = threading.Thread(target=do_child_thread)
+    worker.daemon = True
+    worker.start()
+
+    if verbose:
+        print("child: waiting for shut-down request from parent")
+    child_work_queue.get()
+    if verbose:
+        print("child: received shut-down request.  Child exiting.")
+
+
+class LinuxPreKillTestCase(TestCase):
+
+    def __init__(self, methodName):
+        super(LinuxPreKillTestCase, self).__init__(methodName)
+        self.process = None
+        self.child_work_queue = None
+        self.verbose = False
+        # self.verbose = True
+
+    def tearDown(self):
+        if self.verbose:
+            print("parent: sending shut-down request to child")
+        if self.process:
+            self.child_work_queue.put("hello, child")
+            self.process.join()
+        if self.verbose:
+            print("parent: child is fully shut down")
+
+    def test_sample(self):
+        # Ensure we're Darwin.
+        if platform.system() != 'Linux':
+            self.skipTest("requires a Linux-based OS")
+
+        # Ensure we have the 'perf' tool.  If not, skip the test.
+        try:
+            perf_version = subprocess.check_output(["perf", "version"])
+            if perf_version is None or not (
+                    perf_version.startswith("perf version")):
+                raise Exception("The perf executable doesn't appear"
+                                " to be the Linux perf tools perf")
+        except Exception:
+            self.skipTest("requires the Linux perf tools 'perf' command")
+
+        # Start the child process.
+        self.child_work_queue = Queue()
+        parent_work_queue = Queue()
+        self.process = Process(target=do_child_process,
+                               args=(self.child_work_queue, parent_work_queue,
+                                     self.verbose))
+        if self.verbose:
+            print("parent: starting child")
+        self.process.start()
+
+        # Wait for the child to report its pid.  Then we know we're running.
+        if self.verbose:
+            print("parent: waiting for child to start")
+        child_pid = parent_work_queue.get()
+
+        # Sample the child process.
+        from linux import do_pre_kill
+        context_dict = {
+            "archs": [platform.machine()],
+            "platform_name": None,
+            "platform_url": None,
+            "platform_working_dir": None
+        }
+
+        if self.verbose:
+            print("parent: running pre-kill action on child")
+        output_io = StringIO()
+        do_pre_kill(child_pid, context_dict, output_io)
+        output = output_io.getvalue()
+
+        if self.verbose:
+            print("parent: do_pre_kill() wrote the following output:", output)
+        self.assertIsNotNone(output)
+
+        # We should have a samples count entry.
+        # Samples:
+        self.assertTrue("Samples:" in output, "should have found a 'Samples:' "
+                        "field in the sampled process output")
+
+        # We should see an event count entry
+        event_count_re = re.compile(r"Event count[^:]+:\s+(\d+)")
+        match = event_count_re.search(output)
+        self.assertIsNotNone(match, "should have found the event count entry "
+                             "in sample output")
+        if self.verbose:
+            print("cpu-clock events:", match.group(1))
+
+        # We should see some percentages in the file.
+        percentage_re = re.compile(r"\d+\.\d+%")
+        match = percentage_re.search(output)
+        self.assertIsNotNone(match, "should have found at least one percentage "
+                             "in the sample output")
+
+
+if __name__ == "__main__":
+    main()