fix #1069 / freebsd: cpu_num() may return 255; now returns -1

HISTORY.rst

@@ -54,6 +54,8 @@
 - 1064_: [NetBSD] swap_memory() may segfault in case of error.
 - 1065_: [OpenBSD] Process.cmdline() may raise SystemError.
 - 1067_: [NetBSD] Process.cmdline() leaks memory if proces has terminated.
+- 1069_: [FreeBSD] Process.cpu_num() may return 255 for certain kernel
+  processes.
 
 **Porting notes**
 

docs/index.rst

@@ -1472,6 +1472,7 @@ Process class
 
     Return what CPU this process is currently running on.
     The returned number should be ``<=`` :func:`psutil.cpu_count()`.
+    On FreeBSD certain kernel process may return ``-1``.
     It may be used in conjunction with ``psutil.cpu_percent(percpu=True)`` to
     observe the system workload distributed across multiple CPUs as shown by
     `cpu_distribution.py <https://github.com/giampaolo/psutil/blob/master/scripts/cpu_distribution.py>`__ example script.

psutil/_psutil_bsd.c

@@ -197,7 +197,7 @@ psutil_proc_oneshot_info(PyObject *self, PyObject *args) {
     long memtext;
     long memdata;
     long memstack;
-    unsigned char oncpu;
+    int oncpu;
     kinfo_proc kp;
     long pagesize = sysconf(_SC_PAGESIZE);
     char str[1000];
@@ -252,6 +252,7 @@ psutil_proc_oneshot_info(PyObject *self, PyObject *args) {
     // what CPU we're on; top was used as an example:
     // https://svnweb.freebsd.org/base/head/usr.bin/top/machine.c?
     //     view=markup&pathrev=273835
+    // XXX - note: for "intr" PID this is -1.
     if (kp.ki_stat == SRUN && kp.ki_oncpu != NOCPU)
         oncpu = kp.ki_oncpu;
     else
@@ -300,7 +301,7 @@ psutil_proc_oneshot_info(PyObject *self, PyObject *args) {
         memdata,                          // (long) mem data
         memstack,                         // (long) mem stack
         // others
-        oncpu,                            // (unsigned char) the CPU we are on
+        oncpu,                            // (int) the CPU we are on
 #elif defined(PSUTIL_OPENBSD) || defined(PSUTIL_NETBSD)
         //
         (long)kp.p_ppid,                 // (long) ppid
@@ -336,7 +337,7 @@ psutil_proc_oneshot_info(PyObject *self, PyObject *args) {
         memdata,                          // (long) mem data
         memstack,                         // (long) mem stack
         // others
-        oncpu,                            // (unsigned char) the CPU we are on
+        oncpu,                            // (int) the CPU we are on
 #endif
         py_name                           // (pystr) name
     );

psutil/tests/test_contracts.py

@@ -468,10 +468,12 @@ def cpu_percent(self, ret, proc):
 
     def cpu_num(self, ret, proc):
         self.assertIsInstance(ret, int)
+        if FREEBSD and ret == -1:
+            return
         self.assertGreaterEqual(ret, 0)
         if psutil.cpu_count() == 1:
             self.assertEqual(ret, 0)
-        self.assertIn(ret, range(psutil.cpu_count()))
+        self.assertIn(ret, list(range(psutil.cpu_count())))
 
     def memory_info(self, ret, proc):
         assert is_namedtuple(ret)