i#6938 sched migrate: Add scheduler lock ownership asserts

Adds a std::mutex wrapper which stores the owner so we can assert on
lock ownership.

Adds lock ownership asserts to scheduler functions whose comments say
they require a lock on entry.

Fixes several cases of missing locks found by these asserts.

Issue: #6938

clients/drcachesim/common/mutex_dbg_owned.h

@@ -0,0 +1,95 @@
+/* **********************************************************
+ * Copyright (c) 2024 Google, Inc.  All rights reserved.
+ * **********************************************************/
+
+/*
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice,
+ *   this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * * Neither the name of Google, Inc. nor the names of its contributors may be
+ *   used to endorse or promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL VMWARE, INC. OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ */
+
+/* mutex_dbg_owned.h: std::mutex plus an assertable owner in debug builds. */
+
+#ifndef _MUTEX_DBG_OWNED_H_
+#define _MUTEX_DBG_OWNED_H_ 1
+
+#include <mutex>
+#include <thread>
+
+namespace dynamorio {
+namespace drmemtrace {
+
+// A wrapper around std::mutex which adds an owner field for asserts on ownership
+// when a lock is required to be held by the caller (where
+// std::unique_lock::owns_lock() cannot easily be used).  The owner field is only
+// maintained when NDEBUG is not defined: i.e., it is targeted for asserts.
+class mutex_dbg_owned {
+public:
+    void
+    lock()
+    {
+        lock_.lock();
+#ifndef NDEBUG
+        owner_ = std::this_thread::get_id();
+#endif
+    }
+    bool
+    try_lock()
+    {
+#ifdef NDEBUG
+        return lock_.try_lock().
+#else
+        if (lock_.try_lock()) {
+            owner_ = std::this_thread::get_id();
+            return true;
+        }
+        return false;
+#endif
+    }
+    void
+    unlock()
+    {
+#ifndef NDEBUG
+        owner_ = std::thread::id();
+#endif
+        lock_.unlock();
+    }
+    // This query should only be called when the lock is required to be held
+    // as it is racy when the lock is not held.
+    bool
+    owned_by_cur_thread()
+    {
+        return owner_ == std::this_thread::get_id();
+    }
+
+private:
+    std::mutex lock_;
+    std::thread::id owner_;
+};
+
+} // namespace drmemtrace
+} // namespace dynamorio
+
+#endif /* _MUTEX_DBG_OWNED_H_ */