[Mlir-commits] [mlir] b82f374 - Revert "Minor fixes on the MLIR ActionProfiler (NFC)"

[Mehdi Amini]

Author: Mehdi Amini
Date: 2023-10-03T12:15:35-07:00
New Revision: b82f3747dac0ea3508656f9cd08ad0dbc03ca16d

URL: https://github.com/llvm/llvm-project/commit/b82f3747dac0ea3508656f9cd08ad0dbc03ca16d
DIFF: https://github.com/llvm/llvm-project/commit/b82f3747dac0ea3508656f9cd08ad0dbc03ca16d.diff

LOG: Revert "Minor fixes on the MLIR ActionProfiler (NFC)"

This reverts commit 0502d83470202de6412d4b310692c7b06f1791cb.

This introduces a race condition on the printComma variable.

Added: 
    

Modified: 
    mlir/include/mlir/Debug/Observers/ActionProfiler.h
    mlir/lib/Debug/Observers/ActionProfiler.cpp

Removed: 
    


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diff  --git a/mlir/include/mlir/Debug/Observers/ActionProfiler.h b/mlir/include/mlir/Debug/Observers/ActionProfiler.h
index 8b324ea46eaba09..50ee4f0baf2b096 100644
--- a/mlir/include/mlir/Debug/Observers/ActionProfiler.h
+++ b/mlir/include/mlir/Debug/Observers/ActionProfiler.h
@@ -41,7 +41,7 @@ struct ActionProfiler : public ExecutionContext::Observer {
   std::chrono::time_point<std::chrono::steady_clock> startTime;
   bool printComma = false;
 
-  /// A mutex used to guard printing from multiple threads.
+  /// A mutex used to guard profiling.
   std::mutex mutex;
 };
 

diff  --git a/mlir/lib/Debug/Observers/ActionProfiler.cpp b/mlir/lib/Debug/Observers/ActionProfiler.cpp
index b08d5a24526b6a9..07bf9fd0ccc7db8 100644
--- a/mlir/lib/Debug/Observers/ActionProfiler.cpp
+++ b/mlir/lib/Debug/Observers/ActionProfiler.cpp
@@ -36,8 +36,6 @@ void ActionProfiler::print(const ActionActiveStack *action,
   // Create the event.
   std::string str;
   llvm::raw_string_ostream event(str);
-  if (printComma)
-    event << ",\n";
   event << "{";
   event << R"("name": ")" << action->getAction().getTag() << "\", ";
   event << R"("cat": "PERF", )";
@@ -54,11 +52,12 @@ void ActionProfiler::print(const ActionActiveStack *action,
     event << "\"}";
   }
   event << "}";
-  event.flush();
 
-  // Print the event, guard with a mutex to ensure the stream is correctly
-  // formed.
+  // Print the event.
   std::lock_guard<std::mutex> guard(mutex);
+  if (printComma)
+    os << ",\n";
   printComma = true;
   os << event.str();
+  os.flush();
 }