[PATCH] D29103: [tsan] Properly describe GCD worker threads in reports

[Dmitry Vyukov via Phabricator via llvm-commits]

dvyukov added inline comments.


================
Comment at: lib/tsan/rtl/tsan_report.cc:239
+  const char *thread_status = rt->running ? "running" : "finished";
+  if (rt->parent_tid == kInvalidTid) {
+    Printf(" (tid=%zu, %s) is a GCD worker thread\n", rt->os_id, thread_status);
----------------
This feels like an abuse of kInvalidTid.
Currently we just say that we don't know who is the parent of GCD threads on creation. Which looks legit. But now you are saying: if we don't know a parent of any thread, then it must be a GCD worker thread.

Please mark GCD worker threads more explicitly (either by introducing another special tid, or by marking them with a new flag).
tsan_report.cc is meant to be as dump as possible and just format what it receives. So preferably this should also be a new flag in ReportThread.


Repository:
  rL LLVM

https://reviews.llvm.org/D29103