profcs task status will now show CPU is SMP is enabled

ChangeLog

@@ -11496,3 +11496,6 @@
 	  actions from the TCB to the group structure.  Signal handlers are not
 	  per thread but, rather, per task group.  I know, I preferred it the
 	  other way too, but this is more compliant with POSIX (2016-02-18).
+	* fs/ procfs/fs_procfsproc.c: Add support for showing CPU if SMP is
+	  is enabled (2016-02-19).
+

TODO

@@ -1,4 +1,5 @@
 NuttX TODO List (Last updated February 18, 2016)
+NuttX TODO List (Last updated February 18, 2016)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 This file summarizes known NuttX bugs, limitations, inconsistencies with
@@ -1621,7 +1622,12 @@ o Linux/Cywgin simulation (arch/sim)
                not an issue with the NuttX SMP logic but more likely some chaos
                in the pthread controls. I have seen similar such strange behavior
                other times that I have tried to use setjmp/longmp from a signal
-               handler!
+               handler! Like when I tried to implement simulated interrupts
+               using signals.
+
+               Apparently, if longjmp is invoked from the context of a signal
+               handler, the result is undefined:
+               http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1318.htm
 
                You can enable SMP for ostest configuration by enabling:
 

fs/procfs/fs_procfsproc.c

@@ -375,6 +375,7 @@ static FAR const struct proc_node_s *proc_findnode(FAR const char *relpath)
  *   Type:       xxxxxxx            {Task, pthread, Kthread, Invalid}
  *   PPID:       xxxxx              Parent thread ID
  *   Group:      xxxxx              Group ID
+ *   CPU:        xxx                CPU (CONFIG_SMP only)
  *   State:      xxxxxxxx,xxxxxxxxx {Invalid, Waiting, Ready, Running, Inactive},
  *                                  {Unlock, Semaphore, Signal, MQ empty, MQ full}
  *   Flags:      xxx                N,P,X
@@ -461,6 +462,30 @@ static ssize_t proc_status(FAR struct proc_file_s *procfile,
     }
 #endif
 
+#ifdef CONFIG_SMP
+  if (tcb->task_state >= FIRST_ASSIGNED_STATE &&
+      tcb->task_state <= LAST_ASSIGNED_STATE)
+    {
+      linesize   = snprintf(procfile->line, STATUS_LINELEN, "%-12s%d\n", "CPU:",
+                            tcb->cpu);
+    }
+  else
+    {
+      linesize   = snprintf(procfile->line, STATUS_LINELEN, "%-12s---\n", "CPU:");
+    }
+
+  copysize   = procfs_memcpy(procfile->line, linesize, buffer, remaining, &offset);
+
+  totalsize += copysize;
+  buffer    += copysize;
+  remaining -= copysize;
+
+  if (totalsize >= buflen)
+    {
+      return totalsize;
+    }
+#endif
+
   /* Show the thread state */
 
   linesize   = snprintf(procfile->line, STATUS_LINELEN, "%-12s%s\n", "State:",

include/nuttx/sched.h

@@ -222,6 +222,8 @@ typedef enum tstate_e tstate_t;
 
 #define FIRST_READY_TO_RUN_STATE   TSTATE_TASK_READYTORUN
 #define LAST_READY_TO_RUN_STATE    TSTATE_TASK_RUNNING
+#define FIRST_ASSIGNED_STATE       TSTATE_TASK_ASSIGNED
+#define LAST_ASSIGNED_STATE        TSTATE_TASK_RUNNING
 #define FIRST_BLOCKED_STATE        TSTATE_TASK_INACTIVE
 #define LAST_BLOCKED_STATE         (NUM_TASK_STATES-1)