Modern C++ Programming Cookbook

Avoiding using recursive mutexes

The standard library provides several mutex types for protecting access to shared resources. std::recursive_mutex and std::recursive_timed_mutex are two implementations that allow you to use multiple locking in the same thread. A typical use of a recursive mutex is to protect access to a shared resource from a recursive function. Recursive mutexes have a greater overhead than non-recursive mutexes and, when possible, they should be avoided. This recipe presents a use case for transforming a thread-safe type using a recursive mutex into a thread-safe type using a non-recursive mutex.