sched/signal: Simplified Implementation for SIGEV_THREAD_TID

boards/arm/stm32/olimex-stm32-p407/scripts/memory.ld

@@ -92,7 +92,7 @@ MEMORY
 
   /* 112Kb of contiguous SRAM */
 
-  ksram (rwx)      : ORIGIN = 0x20000000, LENGTH = 16K
-  usram (rwx)      : ORIGIN = 0x20004000, LENGTH = 16K
-  xsram (rwx)      : ORIGIN = 0x20008000, LENGTH = 80K
+  ksram (rwx)      : ORIGIN = 0x20000000, LENGTH = 8K
+  usram (rwx)      : ORIGIN = 0x20002000, LENGTH = 8K
+  xsram (rwx)      : ORIGIN = 0x20008000, LENGTH = 96K
 }

include/nuttx/signal.h

@@ -63,9 +63,11 @@
 
 struct sigwork_s
 {
+#ifdef CONFIG_SIG_EVTHREAD
   struct work_s work;           /* Work queue structure */
   union sigval value;           /* Data passed with notification */
   sigev_notify_function_t func; /* Notification function */
+#endif
 };
 
 #ifdef __cplusplus

sched/signal/sig_dispatch.c

@@ -600,7 +600,7 @@ int nxsig_tcbdispatch(FAR struct tcb_s *stcb, siginfo_t *info)
  *
  ****************************************************************************/
 
-int nxsig_dispatch(pid_t pid, FAR siginfo_t *info)
+int nxsig_dispatch(pid_t pid, FAR siginfo_t *info, bool thread)
 {
 #ifdef HAVE_GROUP_MEMBERS
   FAR struct tcb_s *stcb;
@@ -631,17 +631,30 @@ int nxsig_dispatch(pid_t pid, FAR siginfo_t *info)
 
   if (group != NULL)
     {
-      /* Yes.. call group_signal() to send the signal to the correct group
-       * member.
-       */
+      if (thread)
+        {
+          /* Before the notification, we should validate the tid and
+           * and make sure that the notified thread is in same process
+           * with the current thread.
+           */
 
-      return group_signal(group, info);
-    }
-  else
-    {
-      return -ESRCH;
+          if (stcb != NULL && group == this_task()->group)
+            {
+              return nxsig_tcbdispatch(stcb, info);
+            }
+        }
+      else
+        {
+          /* Yes.. call group_signal() to send the signal to the correct
+           * group member.
+           */
+
+          return group_signal(group, info);
+        }
     }
 
+  return -ESRCH;
+
 #else
   FAR struct tcb_s *stcb;
 

sched/signal/sig_kill.c

@@ -109,7 +109,7 @@ int nxsig_kill(pid_t pid, int signo)
 
   /* Send the signal */
 
-  return nxsig_dispatch(pid, &info);
+  return nxsig_dispatch(pid, &info, false);
 }
 
 /****************************************************************************

sched/signal/sig_notification.c

@@ -112,18 +112,19 @@ int nxsig_notification(pid_t pid, FAR struct sigevent *event,
 
   if (event->sigev_notify & SIGEV_SIGNAL)
     {
-      FAR struct tcb_s *rtcb = this_task();
       siginfo_t info;
+      bool      thread = false;
 
       /* Yes.. Create the siginfo structure */
 
       info.si_signo  = event->sigev_signo;
       info.si_code   = code;
       info.si_errno  = OK;
 #ifdef CONFIG_SCHED_HAVE_PARENT
-      info.si_pid    = rtcb->pid;
+      info.si_pid    = this_task()->pid;
       info.si_status = OK;
 #endif
+      info.si_user   = NULL;
 
       /* Some compilers (e.g., SDCC), do not permit assignment of aggregates.
        * Use of memcpy() is overkill;  We could just copy the larger of the
@@ -133,26 +134,17 @@ int nxsig_notification(pid_t pid, FAR struct sigevent *event,
 
       memcpy(&info.si_value, &event->sigev_value, sizeof(union sigval));
 
-      /* Used only by POSIX timer. Notice that it is UNSAFE, unless
-       * we GUARANTEE that event->sigev_notify_thread_id is valid.
-       */
+      /* SIGEV_THREAD_ID currently used only by POSIX timer. */
 
       if (event->sigev_notify & SIGEV_THREAD_ID)
         {
-          rtcb = nxsched_get_tcb(event->sigev_notify_thread_id);
-          if (rtcb != NULL)
-            {
-              return nxsig_tcbdispatch(rtcb, &info);
-            }
-          else
-            {
-              return -ENOENT;
-            }
+          thread = true;
+          pid = event->sigev_notify_thread_id;
         }
 
       /* Send the signal */
 
-      return nxsig_dispatch(pid, &info);
+      return nxsig_dispatch(pid, &info, thread);
     }
 
 #ifdef CONFIG_SIG_EVTHREAD

sched/signal/sig_queue.c

@@ -106,7 +106,7 @@ int nxsig_queue(int pid, int signo, union sigval value)
 
   /* Send the signal */
 
-  return nxsig_dispatch(pid, &info);
+  return nxsig_dispatch(pid, &info, false);
 }
 
 /****************************************************************************

sched/signal/signal.h

@@ -168,7 +168,8 @@ int                nxsig_default_initialize(FAR struct tcb_s *tcb);
 
 int                nxsig_tcbdispatch(FAR struct tcb_s *stcb,
                                      FAR siginfo_t *info);
-int                nxsig_dispatch(pid_t pid, FAR siginfo_t *info);
+int                nxsig_dispatch(pid_t pid, FAR siginfo_t *info,
+                                  bool thread);
 
 /* sig_cleanup.c */
 

sched/timer/timer_create.c

@@ -191,25 +191,6 @@ int timer_create(clockid_t clockid, FAR struct sigevent *evp,
 
   if (evp)
     {
-      FAR struct tcb_s *ntcb;
-
-      /* Check the SIGEV_THREAD_ID and validate the tid */
-
-      if (evp->sigev_notify & SIGEV_THREAD_ID)
-        {
-          /* Make sure that the notified thread is
-           * in same process with current thread.
-           */
-
-          ntcb = nxsched_get_tcb(evp->sigev_notify_thread_id);
-
-          if (ntcb == NULL || tcb->group != ntcb->group)
-            {
-              set_errno(EINVAL);
-              return ERROR;
-            }
-        }
-
       /* Yes, copy the entire struct sigevent content */
 
       memcpy(&ret->pt_event, evp, sizeof(struct sigevent));