New standard C11 has support atomic operations. Atomic operations was supported since version 4.9.x of GCC compiler. The project implemented atomic operations such as atomic_fetch_xxx (xxx is add, sub, and, or, xor) and atomic_exchange for int type.
You can use this set of functions in old projects that uses previous version of GCC. If transfer of the project to new standard C11 is difficult.
This implementation does not contain memory barriers (DMB - command for ARM). Therefore, there can't be used to implement the synchronization primitives. If you using GCC 4.9.0 or higher, use standard atomic operations according of STD C11.
This implementation supports the following architectures: ARMv6, ARMv6J, ARMv6K, ARMv6Z, ARMv6ZK, ARMv7, ARMv7A, ARMv7R
You need to include atomic_arm.h file in your .c file.
#include "atomic_arm.h" //use our atomic functions
//Then we can use the atomic functions.And add file atomic_arm.S to list of source files to compile. (see an example)