python: Log PyPerf stdout+stderr after a restart (#634)

intel · Dec 20, 2022 · 92a57b7 · 92a57b7
1 parent edd2ffd
commit 92a57b7
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Showing 2 changed files with 16 additions and 4 deletions.
diff --git a/gprofiler/profilers/python.py b/gprofiler/profilers/python.py
@@ -426,7 +426,13 @@ def snapshot(self) -> ProcessToProfileData:
             try:
                 return self._ebpf_profiler.snapshot()
             except PythonEbpfError as e:
-                logger.warning("Python eBPF profiler failed, restarting PyPerf...", exit_code=e.returncode)
+                assert not self._ebpf_profiler.is_running()
+                logger.warning(
+                    "Python eBPF profiler failed, restarting PyPerf...",
+                    pyperf_exit_code=e.returncode,
+                    pyperf_stdout=e.stdout,
+                    pyperf_stderr=e.stderr,
+                )
                 self._ebpf_profiler.start()
                 return {}  # empty this round
         else:

diff --git a/gprofiler/profilers/python_ebpf.py b/gprofiler/profilers/python_ebpf.py
@@ -205,7 +205,8 @@ def start(self) -> None:
             self.process = process
 
     def _dump(self) -> Path:
-        assert self.process is not None, "profiling not started!"
+        assert self.is_running()
+        assert self.process is not None  # for mypy
         self.process.send_signal(self._DUMP_SIGNAL)
 
         try:
@@ -215,7 +216,6 @@ def _dump(self) -> Path:
             # also, makes sure its output pipe doesn't fill up.
             # using read1() which performs just a single read() call and doesn't read until EOF
             # (unlike Popen.communicate())
-            assert self.process is not None
             logger.debug(f"PyPerf output: {self.process.stderr.read1()}")  # type: ignore
             return output
         except TimeoutError:
@@ -252,13 +252,19 @@ def snapshot(self) -> ProcessToProfileData:
 
     def _terminate(self) -> Optional[int]:
         code = None
-        if self.process is not None:
+        if self.is_running():
+            assert self.process is not None  # for mypy
             self.process.terminate()  # okay to call even if process is already dead
             code = self.process.wait()
             self.process = None
+
+        assert self.process is None  # means we're not running
         return code
 
     def stop(self) -> None:
         code = self._terminate()
         if code is not None:
             logger.info("Finished profiling Python processes with PyPerf")
+
+    def is_running(self) -> bool:
+        return self.process is not None