[PATCH] D65708: [NFC][DirectoryWatchedTests] Unlocking mutexes before signaling condition variable.

[Puyan Lotfi via Phabricator via cfe-commits]

plotfi created this revision.
Herald added a project: clang.
Herald added a subscriber: cfe-commits.
plotfi added reviewers: compnerd, jkorous.
Herald added a subscriber: dexonsmith.

This should not affect actual behavior, but should pessimize the threading less by avoiding the situation where:

- mutex is still locked
- T1 notifies on condition variable
- T2 wakes to check mutex
- T2 sees mutex is still locked
- T2 waits
- T1 unlocks mutex
- T2 tries again, acquires mutex.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D65708

Files:
  clang/unittests/DirectoryWatcher/DirectoryWatcherTest.cpp


Index: clang/unittests/DirectoryWatcher/DirectoryWatcherTest.cpp
===================================================================
--- clang/unittests/DirectoryWatcher/DirectoryWatcherTest.cpp
+++ clang/unittests/DirectoryWatcher/DirectoryWatcherTest.cpp
@@ -132,8 +132,10 @@
     } else {
       ExpectedInitial.erase(It);
     }
-    if (result())
+    if (result()) {
+      L.unlock();
       ResultIsReady.notify_one();
+    }
   }
 
   void consumeNonInitial(DirectoryWatcher::Event E) {
@@ -151,8 +153,10 @@
     } else {
       ExpectedNonInitial.erase(It);
     }
-    if (result())
+    if (result()) {
+      L.unlock();
       ResultIsReady.notify_one();
+    }
   }
 
   // This method is used by DirectoryWatcher.


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