Use proc_events on Java processes

gprofiler/profilers/java.py

@@ -13,6 +13,7 @@
 from typing import List, Optional, Set
 
 import psutil
+from granulate_utils.linux import proc_events
 from granulate_utils.linux.oom import get_oom_entry
 from granulate_utils.linux.signals import get_signal_entry
 from packaging.version import Version
@@ -114,6 +115,23 @@ def get_ap_log(self) -> str:
         return self._ap_log
 
 
+class AsyncProfiledProcessMonitor:
+    def __init__(self):
+        self._attached_processes: List[int] = []
+        proc_events.register_exit_callback(self._proc_exit_callback)
+
+    def _proc_exit_callback(self, tid: int, pid: int, exit_code: int):
+        # Notice that we only check the exit code of the main thread here.
+        # It's assumed that an error in any of the Java threads will be reflected in the exit code of the main thread.
+        if tid in self._attached_processes:
+            if exit_code != 0:
+                logger.warning(f"Async-profiled Java process {tid} exited with error code: {hex(exit_code)}")
+            self._attached_processes.remove(tid)
+
+    def register_process(self, pid: int):
+        self._attached_processes.append(pid)
+
+
 @functools.lru_cache(maxsize=1)
 def jattach_path() -> str:
     return resource_path("java/jattach")
@@ -538,6 +556,7 @@ def __init__(
         self._mode = java_async_profiler_mode
         self._safemode = java_async_profiler_safemode
         self._saved_mlock: Optional[int] = None
+        self._process_monitor = AsyncProfiledProcessMonitor()
         self._java_safemode = java_safemode
         if self._java_safemode:
             logger.debug("Java safemode enabled")
@@ -663,6 +682,7 @@ def _profile_process(self, process: Process) -> Optional[StackToSampleCount]:
         with AsyncProfiledProcess(
             process, self._storage_dir, self._buildids, self._mode, self._safemode, self._java_safemode
         ) as ap_proc:
+            self._process_monitor.register_process(process.pid)
             return self._profile_ap_process(ap_proc)
 
     def _profile_ap_process(self, ap_proc: AsyncProfiledProcess) -> Optional[StackToSampleCount]: