Merge pull request #302 from xcp-ng/abo/new-test-perf-probe

Add a new test on 'perf probe' bug

Author: stormi

tests/packages/linux_image/__init__.py

@@ -0,0 +1,15 @@
+import logging
+import pytest
+import urllib.request
+
+# Explicitly import package-scoped fixtures (see explanation in pkgfixtures.py)
+from pkgfixtures import host_with_saved_yum_state
+
+@pytest.fixture(scope="package")
+def host_with_perf(host_with_saved_yum_state):
+    host = host_with_saved_yum_state
+
+    logging.info(f"Getting perf package")
+
+    host.yum_install(['perf'])
+    yield host

tests/packages/linux_image/conftest.py

@@ -0,0 +1,29 @@
+# Requirements:
+# From --hosts parameter:
+# - host(A1): any xcp-ng host
+import re
+
+def perf_probe(host, probe):
+    host.ssh(['perf', 'probe', '--add', probe])
+    host.ssh(['perf', 'record', '-e', 'probe:' + probe, '-o', '~/perf.data', '-aR', '--', 'sleep', '10'])
+    host.ssh(['perf', 'probe', '--del', probe])
+
+    samples = host.ssh(['perf', 'report', '-i', '~/perf.data', '-D', '--stdio-color', 'never'])
+    host.ssh(['rm', '~/perf.data'])
+
+    return re.findall(r'RECORD_SAMPLE', samples)
+
+def test_linux_image_perf_probe(host_with_perf):
+    # Probe that triggers very often:
+    probe = 'xen_flush_tlb_one_user'
+
+    match = perf_probe(host_with_perf, probe)
+
+    assert len(match) > 0, "No sample found for probe %s!" % probe
+
+    # Example of a function that isn't called often:
+    probe = 'xenbus_backend_ioctl'
+
+    match = perf_probe(host_with_perf, probe)
+
+    assert len(match) == 0, "Samples found for probe %s!" % probe