Function sys_heap_release_hook 

pub unsafe extern "C" fn sys_heap_release_hook(
    mem: *mut c_void,
    bytes: usize,
)

@brief Heap memory release hook

Provided by the consumer that selects CONFIG_SYS_HEAP_RELEASE_HOOK. Called with the memory still valid, from sys_heap_free() with the released block and from an in-place shrink with the released tail. The caller may hold a heap lock, so the hook must not allocate from or free to a heap. With CONFIG_USERSPACE the common libc free() may enter it from user mode.

@param mem Start of the released memory @param bytes Size of the released memory