fatal error: asm/atomic.h: No such file or directory on debian10 os

My system is debian 10. I want to implement atomic operations, but I find that there are no header files and API functions for atomic operations. What's the matter? Isn't atomic operation a kernel level function? Why not?

test_atomic.c:

#include <stdio.h>
#include <asm/atomic.h>

int main(void)
{
     printf("test atomic!\n");
     return 0;
}

compile error:

# gcc test_atomic.c
test_atomic.c:2:10: fatal error: asm/atomic.h: No such file or directory
 #include <asm/atomic.h>
          ^~~~~~~~~~~~~~
compilation terminated.

man atomic API error:

# man atomic_add
No manual entry for atomic_add