[compiler-rt] [llvm] [ctxprof] root autodetection mechanism (PR #133147)

[Snehasish Kumar via llvm-commits]

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@@ -53,5 +54,35 @@ class PerThreadCallsiteTrie {
   /// thread, together with the number of samples that included them.
   DenseMap<uptr, uint64_t> determineRoots() const;
 };
+
+class RootAutoDetector final {
+  static const uint64_t SampleRate = 6113;
+  const unsigned WaitSeconds;
+  pthread_t WorkerThread;
+
+  struct PerThreadSamples {
+    PerThreadSamples(RootAutoDetector &Parent);
+
+    PerThreadCallsiteTrie TrieRoot;
+    SpinMutex M;
+  };
+  SpinMutex AllSamplesMutex;
+  SANITIZER_GUARDED_BY(AllSamplesMutex)
+  Vector<PerThreadSamples *> AllSamples;
+  atomic_uintptr_t &FunctionDataListHead;
+  atomic_uintptr_t &Self;
+  void collectStack();
+
+public:
+  RootAutoDetector(atomic_uintptr_t &FunctionDataListHead,
+                   atomic_uintptr_t &Self, unsigned WaitSeconds)
+      : WaitSeconds(WaitSeconds), FunctionDataListHead(FunctionDataListHead),
+        Self(Self) {}
+
+  void sample();
+  void start();
+  void join();
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snehasish wrote:

Add a comment describing the public methods?

https://github.com/llvm/llvm-project/pull/133147