bpo-37077: Add native thread ID (TID) for AIX (GH-13624)

This is the followup  for issue36084



https://bugs.python.org/issue37077

Doc/library/_thread.rst

@@ -106,7 +106,7 @@ This module defines the following constants and functions:
    Its value may be used to uniquely identify this particular thread system-wide
    (until the thread terminates, after which the value may be recycled by the OS).
 
-   .. availability:: Windows, FreeBSD, Linux, macOS, OpenBSD, NetBSD.
+   .. availability:: Windows, FreeBSD, Linux, macOS, OpenBSD, NetBSD, AIX.
 
    .. versionadded:: 3.8
 

Doc/library/threading.rst

@@ -82,7 +82,7 @@ This module defines the following functions:
    Its value may be used to uniquely identify this particular thread system-wide
    (until the thread terminates, after which the value may be recycled by the OS).
 
-   .. availability:: Windows, FreeBSD, Linux, macOS, OpenBSD, NetBSD.
+   .. availability:: Windows, FreeBSD, Linux, macOS, OpenBSD, NetBSD, AIX.
 
    .. versionadded:: 3.8
 

Include/pythread.h

@@ -26,7 +26,7 @@ PyAPI_FUNC(unsigned long) PyThread_start_new_thread(void (*)(void *), void *);
 PyAPI_FUNC(void) _Py_NO_RETURN PyThread_exit_thread(void);
 PyAPI_FUNC(unsigned long) PyThread_get_thread_ident(void);
 
-#if defined(__APPLE__) || defined(__linux__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) || defined(_WIN32)
+#if defined(__APPLE__) || defined(__linux__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) || defined(_WIN32) || defined(_AIX)
 #define PY_HAVE_THREAD_NATIVE_ID
 PyAPI_FUNC(unsigned long) PyThread_get_thread_native_id(void);
 #endif

Misc/NEWS.d/next/Core and Builtins/2019-05-28-11-47-44.bpo-37077.S1h0Fc.rst

+Add :func:`threading.get_native_id` support for AIX.
+Patch by M. Felt

Python/thread_pthread.h

@@ -18,8 +18,10 @@
 #   include <pthread_np.h>      /* pthread_getthreadid_np() */
 #elif defined(__OpenBSD__)
 #   include <unistd.h>          /* getthrid() */
-#elif defined(__NetBSD__)       /* _lwp_self */
-#   include <lwp.h>
+#elif defined(_AIX)
+#   include <sys/thread.h>      /* thread_self() */
+#elif defined(__NetBSD__)
+#   include <lwp.h>             /* _lwp_self() */
 #endif
 
 /* The POSIX spec requires that use of pthread_attr_setstacksize
@@ -330,6 +332,9 @@ PyThread_get_thread_native_id(void)
 #elif defined(__OpenBSD__)
     pid_t native_id;
     native_id = getthrid();
+#elif defined(_AIX)
+    tid_t native_id;
+    native_id = thread_self();
 #elif defined(__NetBSD__)
     lwpid_t native_id;
     native_id = _lwp_self();