From Curtis Rubel, "I would like to submit the attached file for inclusion in future releases of

OpenSceneGraph and the OpenThreads library.

The changes in the file simply remove a few ifndef's that currently
do not allow Linux systems to fully utilize the PThread real-time
scheduling API.

Since Linux now fully supports the PThread scheduling API it would
be beneficial to have it available to use as necessary.  I have
been testing this change since OSG release 3.3.7 and have not seen
any ill affects.

The Priority scheduling api is further protected by another ifdef:

#ifdef ALLOW_PRIORITY_SCHEDULING

that only appears to be defined in the pthreads implementation as
well.  This would make it unlikely that anyone would be affected
by this unless they are intentionally wanting to run with priority
scheduling.  In which case on Linux they would need to make
these same modifications themselves to utilize it to its full extent.

Attached file is for the current trunk as of this date.
"


git-svn-id: http://svn.openscenegraph.org/osg/OpenSceneGraph/trunk@15140 16af8721-9629-0410-8352-f15c8da7e697

src/OpenThreads/pthreads/PThread.cpp

@@ -286,8 +286,6 @@ private:
             pthread_getschedparam(thread->getProcessId(),
                       &th_policy, &th_param);
 
-#ifndef __linux__
-
             switch(thread->getSchedulePolicy())
             {
 
@@ -312,24 +310,10 @@ private:
                 break;
             };
 
-#else
-            th_policy = SCHED_OTHER;  // Must protect linux from realtime.
-#endif
-
-#ifdef __linux__
-
-            max_priority = 0;
-            min_priority = 20;
-            nominal_priority = (max_priority + min_priority)/2;
-
-#else
-
             max_priority = sched_get_priority_max(th_policy);
             min_priority = sched_get_priority_min(th_policy);
             nominal_priority = (max_priority + min_priority)/2;
 
-#endif
-
             switch(thread->getSchedulePriority())
             {