8038473: Remove support for old T1 libthread
authorfparain
Thu, 03 Apr 2014 09:28:28 +0000
changeset 23865 ba4aeedb2a9f
parent 23863 76fc8456723d
child 23866 42d397967053
8038473: Remove support for old T1 libthread Reviewed-by: dholmes, coleenp, acorn, dcubed
hotspot/src/os/aix/vm/os_aix.cpp
hotspot/src/os/bsd/vm/os_bsd.cpp
hotspot/src/os/linux/vm/os_linux.cpp
hotspot/src/os/solaris/vm/osThread_solaris.cpp
hotspot/src/os/solaris/vm/osThread_solaris.hpp
hotspot/src/os/solaris/vm/os_solaris.cpp
hotspot/src/os/solaris/vm/os_solaris.hpp
hotspot/src/os/windows/vm/os_windows.cpp
hotspot/src/os/windows/vm/os_windows.inline.hpp
hotspot/src/os_cpu/solaris_sparc/vm/os_solaris_sparc.cpp
hotspot/src/os_cpu/solaris_x86/vm/os_solaris_x86.cpp
hotspot/src/share/vm/runtime/arguments.cpp
hotspot/src/share/vm/runtime/os.hpp
hotspot/src/share/vm/runtime/safepoint.cpp
hotspot/src/share/vm/runtime/sharedRuntime.cpp
hotspot/src/share/vm/runtime/sharedRuntime.hpp
--- a/hotspot/src/os/aix/vm/os_aix.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/aix/vm/os_aix.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2012, 2014 SAP AG. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -2811,18 +2811,13 @@
 
 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN; }
 
-void os::yield_all(int attempts) {
+void os::yield_all() {
   // Yields to all threads, including threads with lower priorities
   // Threads on Linux are all with same priority. The Solaris style
   // os::yield_all() with nanosleep(1ms) is not necessary.
   sched_yield();
 }
 
-// Called from the tight loops to possibly influence time-sharing heuristics
-void os::loop_breaker(int attempts) {
-  os::yield_all(attempts);
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // thread priority support
 
@@ -3079,7 +3074,7 @@
 
   for (int n = 0; !osthread->sr.is_suspended(); n++) {
     for (int i = 0; i < RANDOMLY_LARGE_INTEGER2 && !osthread->sr.is_suspended(); i++) {
-      os::yield_all(i);
+      os::yield_all();
     }
 
     // timeout, try to cancel the request
@@ -3113,7 +3108,7 @@
     if (sr_notify(osthread) == 0) {
       for (int n = 0; n < RANDOMLY_LARGE_INTEGER && !osthread->sr.is_running(); n++) {
         for (int i = 0; i < 100 && !osthread->sr.is_running(); i++) {
-          os::yield_all(i);
+          os::yield_all();
         }
       }
     } else {
--- a/hotspot/src/os/bsd/vm/os_bsd.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/bsd/vm/os_bsd.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -2551,18 +2551,13 @@
 
 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
 
-void os::yield_all(int attempts) {
+void os::yield_all() {
   // Yields to all threads, including threads with lower priorities
   // Threads on Bsd are all with same priority. The Solaris style
   // os::yield_all() with nanosleep(1ms) is not necessary.
   sched_yield();
 }
 
-// Called from the tight loops to possibly influence time-sharing heuristics
-void os::loop_breaker(int attempts) {
-  os::yield_all(attempts);
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // thread priority support
 
--- a/hotspot/src/os/linux/vm/os_linux.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/linux/vm/os_linux.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -3777,18 +3777,13 @@
 
 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
 
-void os::yield_all(int attempts) {
+void os::yield_all() {
   // Yields to all threads, including threads with lower priorities
   // Threads on Linux are all with same priority. The Solaris style
   // os::yield_all() with nanosleep(1ms) is not necessary.
   sched_yield();
 }
 
-// Called from the tight loops to possibly influence time-sharing heuristics
-void os::loop_breaker(int attempts) {
-  os::yield_all(attempts);
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // thread priority support
 
--- a/hotspot/src/os/solaris/vm/osThread_solaris.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/solaris/vm/osThread_solaris.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -49,16 +49,6 @@
 
 // copied from synchronizer.cpp
 
-void OSThread::handle_spinlock_contention(int tries) {
-  if (NoYieldsInMicrolock) return;
-
-  if (tries > 10) {
-    os::yield_all(tries); // Yield to threads of any priority
-  } else if (tries > 5) {
-    os::yield();          // Yield to threads of same or higher priority
-  }
-}
-
 void OSThread::SR_handler(Thread* thread, ucontext_t* uc) {
   os::Solaris::SR_handler(thread, uc);
 }
--- a/hotspot/src/os/solaris/vm/osThread_solaris.hpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/solaris/vm/osThread_solaris.hpp	Thu Apr 03 09:28:28 2014 +0000
@@ -82,8 +82,6 @@
   void set_ucontext(ucontext_t* ptr) { _ucontext = ptr; }
   static void SR_handler(Thread* thread, ucontext_t* uc);
 
-  static void       handle_spinlock_contention(int tries);                      // Used for thread local eden locking
-
   // ***************************************************************
   // Platform dependent initialization and cleanup
   // ***************************************************************
--- a/hotspot/src/os/solaris/vm/os_solaris.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/solaris/vm/os_solaris.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -969,9 +969,6 @@
   return true;
 }
 
-// _T2_libthread is true if we believe we are running with the newer
-// SunSoft lwp/libthread.so (2.8 patch, 2.9 default)
-bool os::Solaris::_T2_libthread = false;
 
 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
   // Allocate the OSThread object
@@ -1056,71 +1053,10 @@
   thread->set_osthread(osthread);
 
   // Create the Solaris thread
-  // explicit THR_BOUND for T2_libthread case in case
-  // that assumption is not accurate, but our alternate signal stack
-  // handling is based on it which must have bound threads
   thread_t tid = 0;
-  long     flags = (UseDetachedThreads ? THR_DETACHED : 0) | THR_SUSPENDED
-                   | ((UseBoundThreads || os::Solaris::T2_libthread() ||
-                       (thr_type == vm_thread) ||
-                       (thr_type == cgc_thread) ||
-                       (thr_type == pgc_thread) ||
-                       (thr_type == compiler_thread && BackgroundCompilation)) ?
-                      THR_BOUND : 0);
+  long     flags = (UseDetachedThreads ? THR_DETACHED : 0) | THR_SUSPENDED;
   int      status;
 
-  // 4376845 -- libthread/kernel don't provide enough LWPs to utilize all CPUs.
-  //
-  // On multiprocessors systems, libthread sometimes under-provisions our
-  // process with LWPs.  On a 30-way systems, for instance, we could have
-  // 50 user-level threads in ready state and only 2 or 3 LWPs assigned
-  // to our process.  This can result in under utilization of PEs.
-  // I suspect the problem is related to libthread's LWP
-  // pool management and to the kernel's SIGBLOCKING "last LWP parked"
-  // upcall policy.
-  //
-  // The following code is palliative -- it attempts to ensure that our
-  // process has sufficient LWPs to take advantage of multiple PEs.
-  // Proper long-term cures include using user-level threads bound to LWPs
-  // (THR_BOUND) or using LWP-based synchronization.  Note that there is a
-  // slight timing window with respect to sampling _os_thread_count, but
-  // the race is benign.  Also, we should periodically recompute
-  // _processors_online as the min of SC_NPROCESSORS_ONLN and the
-  // the number of PEs in our partition.  You might be tempted to use
-  // THR_NEW_LWP here, but I'd recommend against it as that could
-  // result in undesirable growth of the libthread's LWP pool.
-  // The fix below isn't sufficient; for instance, it doesn't take into count
-  // LWPs parked on IO.  It does, however, help certain CPU-bound benchmarks.
-  //
-  // Some pathologies this scheme doesn't handle:
-  // *  Threads can block, releasing the LWPs.  The LWPs can age out.
-  //    When a large number of threads become ready again there aren't
-  //    enough LWPs available to service them.  This can occur when the
-  //    number of ready threads oscillates.
-  // *  LWPs/Threads park on IO, thus taking the LWP out of circulation.
-  //
-  // Finally, we should call thr_setconcurrency() periodically to refresh
-  // the LWP pool and thwart the LWP age-out mechanism.
-  // The "+3" term provides a little slop -- we want to slightly overprovision.
-
-  if (AdjustConcurrency && os::Solaris::_os_thread_count < (_processors_online+3)) {
-    if (!(flags & THR_BOUND)) {
-      thr_setconcurrency (os::Solaris::_os_thread_count);       // avoid starvation
-    }
-  }
-  // Although this doesn't hurt, we should warn of undefined behavior
-  // when using unbound T1 threads with schedctl().  This should never
-  // happen, as the compiler and VM threads are always created bound
-  DEBUG_ONLY(
-      if ((VMThreadHintNoPreempt || CompilerThreadHintNoPreempt) &&
-          (!os::Solaris::T2_libthread() && (!(flags & THR_BOUND))) &&
-          ((thr_type == vm_thread) || (thr_type == cgc_thread) ||
-           (thr_type == pgc_thread) || (thr_type == compiler_thread && BackgroundCompilation))) {
-         warning("schedctl behavior undefined when Compiler/VM/GC Threads are Unbound");
-      }
-  );
-
-
   // Mark that we don't have an lwp or thread id yet.
   // In case we attempt to set the priority before the thread starts.
   osthread->set_lwp_id(-1);
@@ -1145,13 +1081,6 @@
   // Remember that we created this thread so we can set priority on it
   osthread->set_vm_created();
 
-  // Set the default thread priority.  If using bound threads, setting
-  // lwp priority will be delayed until thread start.
-  set_native_priority(thread,
-                      DefaultThreadPriority == -1 ?
-                        java_to_os_priority[NormPriority] :
-                        DefaultThreadPriority);
-
   // Initial thread state is INITIALIZED, not SUSPENDED
   osthread->set_state(INITIALIZED);
 
@@ -1333,39 +1262,8 @@
     jt->set_stack_size(stack_size);
   }
 
-   // 5/22/01: Right now alternate signal stacks do not handle
-   // throwing stack overflow exceptions, see bug 4463178
-   // Until a fix is found for this, T2 will NOT imply alternate signal
-   // stacks.
-   // If using T2 libthread threads, install an alternate signal stack.
-   // Because alternate stacks associate with LWPs on Solaris,
-   // see sigaltstack(2), if using UNBOUND threads, or if UseBoundThreads
-   // we prefer to explicitly stack bang.
-   // If not using T2 libthread, but using UseBoundThreads any threads
-   // (primordial thread, jni_attachCurrentThread) we do not create,
-   // probably are not bound, therefore they can not have an alternate
-   // signal stack. Since our stack banging code is generated and
-   // is shared across threads, all threads must be bound to allow
-   // using alternate signal stacks.  The alternative is to interpose
-   // on _lwp_create to associate an alt sig stack with each LWP,
-   // and this could be a problem when the JVM is embedded.
-   // We would prefer to use alternate signal stacks with T2
-   // Since there is currently no accurate way to detect T2
-   // we do not. Assuming T2 when running T1 causes sig 11s or assertions
-   // on installing alternate signal stacks
-
-
-   // 05/09/03: removed alternate signal stack support for Solaris
-   // The alternate signal stack mechanism is no longer needed to
-   // handle stack overflow. This is now handled by allocating
-   // guard pages (red zone) and stackbanging.
-   // Initially the alternate signal stack mechanism was removed because
-   // it did not work with T1 llibthread. Alternate
-   // signal stacks MUST have all threads bound to lwps. Applications
-   // can create their own threads and attach them without their being
-   // bound under T1. This is frequently the case for the primordial thread.
-   // If we were ever to reenable this mechanism we would need to
-   // use the dynamic check for T2 libthread.
+  // With the T2 libthread (T1 is no longer supported) threads are always bound
+  // and we use stackbanging in all cases.
 
   os::Solaris::init_thread_fpu_state();
   std::set_terminate(_handle_uncaught_cxx_exception);
@@ -2092,12 +1990,7 @@
 }
 
 void os::Solaris::print_libversion_info(outputStream* st) {
-  if (os::Solaris::T2_libthread()) {
-    st->print("  (T2 libthread)");
-  }
-  else {
-    st->print("  (T1 libthread)");
-  }
+  st->print("  (T2 libthread)");
   st->cr();
 }
 
@@ -3323,41 +3216,10 @@
 
 os::YieldResult os::NakedYield() { thr_yield(); return os::YIELD_UNKNOWN; }
 
-
-// On Solaris we found that yield_all doesn't always yield to all other threads.
-// There have been cases where there is a thread ready to execute but it doesn't
-// get an lwp as the VM thread continues to spin with sleeps of 1 millisecond.
-// The 1 millisecond wait doesn't seem long enough for the kernel to issue a
-// SIGWAITING signal which will cause a new lwp to be created. So we count the
-// number of times yield_all is called in the one loop and increase the sleep
-// time after 8 attempts. If this fails too we increase the concurrency level
-// so that the starving thread would get an lwp
-
-void os::yield_all(int attempts) {
+void os::yield_all() {
   // Yields to all threads, including threads with lower priorities
-  if (attempts == 0) {
-    os::sleep(Thread::current(), 1, false);
-  } else {
-    int iterations = attempts % 30;
-    if (iterations == 0 && !os::Solaris::T2_libthread()) {
-      // thr_setconcurrency and _getconcurrency make sense only under T1.
-      int noofLWPS = thr_getconcurrency();
-      if (noofLWPS < (Threads::number_of_threads() + 2)) {
-        thr_setconcurrency(thr_getconcurrency() + 1);
-      }
-    } else if (iterations < 25) {
-      os::sleep(Thread::current(), 1, false);
-    } else {
-      os::sleep(Thread::current(), 10, false);
-    }
-  }
-}
-
-// Called from the tight loops to possibly influence time-sharing heuristics
-void os::loop_breaker(int attempts) {
-  os::yield_all(attempts);
-}
-
+  os::sleep(Thread::current(), 1, false);
+}
 
 // Interface for setting lwp priorities.  If we are using T2 libthread,
 // which forces the use of BoundThreads or we manually set UseBoundThreads,
@@ -3365,6 +3227,9 @@
 // function is meaningless in this mode so we must adjust the real lwp's priority
 // The routines below implement the getting and setting of lwp priorities.
 //
+// Note: T2 is now the only supported libthread. UseBoundThreads flag is
+//       being deprecated and all threads are now BoundThreads
+//
 // Note: There are three priority scales used on Solaris.  Java priotities
 //       which range from 1 to 10, libthread "thr_setprio" scale which range
 //       from 0 to 127, and the current scheduling class of the process we
@@ -3437,29 +3302,19 @@
 
   if (!UseThreadPriorities) return 0;
 
-  // We are using Bound threads, we need to determine our priority ranges
-  if (os::Solaris::T2_libthread() || UseBoundThreads) {
-    // If ThreadPriorityPolicy is 1, switch tables
-    if (ThreadPriorityPolicy == 1) {
-      for (i = 0 ; i < CriticalPriority+1; i++)
-        os::java_to_os_priority[i] = prio_policy1[i];
-    }
-    if (UseCriticalJavaThreadPriority) {
-      // MaxPriority always maps to the FX scheduling class and criticalPrio.
-      // See set_native_priority() and set_lwp_class_and_priority().
-      // Save original MaxPriority mapping in case attempt to
-      // use critical priority fails.
-      java_MaxPriority_to_os_priority = os::java_to_os_priority[MaxPriority];
-      // Set negative to distinguish from other priorities
-      os::java_to_os_priority[MaxPriority] = -criticalPrio;
-    }
-  }
-  // Not using Bound Threads, set to ThreadPolicy 1
-  else {
-    for ( i = 0 ; i < CriticalPriority+1; i++ ) {
+  // If ThreadPriorityPolicy is 1, switch tables
+  if (ThreadPriorityPolicy == 1) {
+    for (i = 0 ; i < CriticalPriority+1; i++)
       os::java_to_os_priority[i] = prio_policy1[i];
-    }
-    return 0;
+  }
+  if (UseCriticalJavaThreadPriority) {
+    // MaxPriority always maps to the FX scheduling class and criticalPrio.
+    // See set_native_priority() and set_lwp_class_and_priority().
+    // Save original MaxPriority mapping in case attempt to
+    // use critical priority fails.
+    java_MaxPriority_to_os_priority = os::java_to_os_priority[MaxPriority];
+    // Set negative to distinguish from other priorities
+    os::java_to_os_priority[MaxPriority] = -criticalPrio;
   }
 
   // Get IDs for a set of well-known scheduling classes.
@@ -3583,10 +3438,6 @@
 
 
 // set_lwp_class_and_priority
-//
-// Set the class and priority of the lwp.  This call should only
-// be made when using bound threads (T2 threads are bound by default).
-//
 int set_lwp_class_and_priority(int ThreadID, int lwpid,
                                int newPrio, int new_class, bool scale) {
   int rslt;
@@ -3812,23 +3663,20 @@
     status = thr_setprio(thread->osthread()->thread_id(), newpri);
   }
 
-  if (os::Solaris::T2_libthread() ||
-      (UseBoundThreads && osthread->is_vm_created())) {
-    int lwp_status =
-      set_lwp_class_and_priority(osthread->thread_id(),
-                                 osthread->lwp_id(),
-                                 newpri,
-                                 fxcritical ? fxLimits.schedPolicy : myClass,
-                                 !fxcritical);
-    if (lwp_status != 0 && fxcritical) {
-      // Try again, this time without changing the scheduling class
-      newpri = java_MaxPriority_to_os_priority;
-      lwp_status = set_lwp_class_and_priority(osthread->thread_id(),
-                                              osthread->lwp_id(),
-                                              newpri, myClass, false);
-    }
-    status |= lwp_status;
-  }
+  int lwp_status =
+          set_lwp_class_and_priority(osthread->thread_id(),
+          osthread->lwp_id(),
+          newpri,
+          fxcritical ? fxLimits.schedPolicy : myClass,
+          !fxcritical);
+  if (lwp_status != 0 && fxcritical) {
+    // Try again, this time without changing the scheduling class
+    newpri = java_MaxPriority_to_os_priority;
+    lwp_status = set_lwp_class_and_priority(osthread->thread_id(),
+            osthread->lwp_id(),
+            newpri, myClass, false);
+  }
+  status |= lwp_status;
   return (status == 0) ? OS_OK : OS_ERR;
 }
 
@@ -4495,13 +4343,6 @@
   }
 }
 
-// (Static) wrappers for the new libthread API
-int_fnP_thread_t_iP_uP_stack_tP_gregset_t os::Solaris::_thr_getstate;
-int_fnP_thread_t_i_gregset_t os::Solaris::_thr_setstate;
-int_fnP_thread_t_i os::Solaris::_thr_setmutator;
-int_fnP_thread_t os::Solaris::_thr_suspend_mutator;
-int_fnP_thread_t os::Solaris::_thr_continue_mutator;
-
 // (Static) wrapper for getisax(2) call.
 os::Solaris::getisax_func_t os::Solaris::_getisax = 0;
 
@@ -4536,78 +4377,9 @@
   return addr;
 }
 
-
-
-// isT2_libthread()
-//
-// Routine to determine if we are currently using the new T2 libthread.
-//
-// We determine if we are using T2 by reading /proc/self/lstatus and
-// looking for a thread with the ASLWP bit set.  If we find this status
-// bit set, we must assume that we are NOT using T2.  The T2 team
-// has approved this algorithm.
-//
-// We need to determine if we are running with the new T2 libthread
-// since setting native thread priorities is handled differently
-// when using this library.  All threads created using T2 are bound
-// threads. Calling thr_setprio is meaningless in this case.
-//
-bool isT2_libthread() {
-  static prheader_t * lwpArray = NULL;
-  static int lwpSize = 0;
-  static int lwpFile = -1;
-  lwpstatus_t * that;
-  char lwpName [128];
-  bool isT2 = false;
-
-#define ADR(x)  ((uintptr_t)(x))
-#define LWPINDEX(ary,ix)   ((lwpstatus_t *)(((ary)->pr_entsize * (ix)) + (ADR((ary) + 1))))
-
-  lwpFile = ::open("/proc/self/lstatus", O_RDONLY, 0);
-  if (lwpFile < 0) {
-      if (ThreadPriorityVerbose) warning ("Couldn't open /proc/self/lstatus\n");
-      return false;
-  }
-  lwpSize = 16*1024;
-  for (;;) {
-    ::lseek64 (lwpFile, 0, SEEK_SET);
-    lwpArray = (prheader_t *)NEW_C_HEAP_ARRAY(char, lwpSize, mtInternal);
-    if (::read(lwpFile, lwpArray, lwpSize) < 0) {
-      if (ThreadPriorityVerbose) warning("Error reading /proc/self/lstatus\n");
-      break;
-    }
-    if ((lwpArray->pr_nent * lwpArray->pr_entsize) <= lwpSize) {
-       // We got a good snapshot - now iterate over the list.
-      int aslwpcount = 0;
-      for (int i = 0; i < lwpArray->pr_nent; i++ ) {
-        that = LWPINDEX(lwpArray,i);
-        if (that->pr_flags & PR_ASLWP) {
-          aslwpcount++;
-        }
-      }
-      if (aslwpcount == 0) isT2 = true;
-      break;
-    }
-    lwpSize = lwpArray->pr_nent * lwpArray->pr_entsize;
-    FREE_C_HEAP_ARRAY(char, lwpArray, mtInternal);  // retry.
-  }
-
-  FREE_C_HEAP_ARRAY(char, lwpArray, mtInternal);
-  ::close (lwpFile);
-  if (ThreadPriorityVerbose) {
-    if (isT2) tty->print_cr("We are running with a T2 libthread\n");
-    else tty->print_cr("We are not running with a T2 libthread\n");
-  }
-  return isT2;
-}
-
-
 void os::Solaris::libthread_init() {
   address func = (address)dlsym(RTLD_DEFAULT, "_thr_suspend_allmutators");
 
-  // Determine if we are running with the new T2 libthread
-  os::Solaris::set_T2_libthread(isT2_libthread());
-
   lwp_priocntl_init();
 
   // RTLD_DEFAULT was not defined on some early versions of 5.5.1
@@ -4618,22 +4390,6 @@
     guarantee(func != NULL, "libthread.so is too old.");
   }
 
-  // Initialize the new libthread getstate API wrappers
-  func = resolve_symbol("thr_getstate");
-  os::Solaris::set_thr_getstate(CAST_TO_FN_PTR(int_fnP_thread_t_iP_uP_stack_tP_gregset_t, func));
-
-  func = resolve_symbol("thr_setstate");
-  os::Solaris::set_thr_setstate(CAST_TO_FN_PTR(int_fnP_thread_t_i_gregset_t, func));
-
-  func = resolve_symbol("thr_setmutator");
-  os::Solaris::set_thr_setmutator(CAST_TO_FN_PTR(int_fnP_thread_t_i, func));
-
-  func = resolve_symbol("thr_suspend_mutator");
-  os::Solaris::set_thr_suspend_mutator(CAST_TO_FN_PTR(int_fnP_thread_t, func));
-
-  func = resolve_symbol("thr_continue_mutator");
-  os::Solaris::set_thr_continue_mutator(CAST_TO_FN_PTR(int_fnP_thread_t, func));
-
   int size;
   void (*handler_info_func)(address *, int *);
   handler_info_func = CAST_TO_FN_PTR(void (*)(address *, int *), resolve_symbol("thr_sighndlrinfo"));
@@ -5536,11 +5292,7 @@
 }
 
 bool os::is_thread_cpu_time_supported() {
-  if ( os::Solaris::T2_libthread() || UseBoundThreads ) {
-    return true;
-  } else {
-    return false;
-  }
+  return true;
 }
 
 // System loadavg support.  Returns -1 if load average cannot be obtained.
--- a/hotspot/src/os/solaris/vm/os_solaris.hpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/solaris/vm/os_solaris.hpp	Thu Apr 03 09:28:28 2014 +0000
@@ -41,19 +41,6 @@
   #define TRS_LWPID       2
   #define TRS_INVALID     3
 
-  // _T2_libthread is true if we believe we are running with the newer
-  // SunSoft lib/lwp/libthread: default Solaris 9, available Solaris 8
-  // which is a lightweight libthread that also supports all T1
-  static bool _T2_libthread;
-  // These refer to new libthread interface functions
-  // They get intialized if we dynamically detect new libthread
-  static int_fnP_thread_t_iP_uP_stack_tP_gregset_t _thr_getstate;
-  static int_fnP_thread_t_i_gregset_t _thr_setstate;
-  static int_fnP_thread_t_i _thr_setmutator;
-  static int_fnP_thread_t _thr_suspend_mutator;
-  static int_fnP_thread_t _thr_continue_mutator;
-  // libthread_init sets the above, if the new functionality is detected
-
   // initialized to libthread or lwp synchronization primitives depending on UseLWPSychronization
   static int_fnP_mutex_tP _mutex_lock;
   static int_fnP_mutex_tP _mutex_trylock;
@@ -214,29 +201,6 @@
   static struct sigaction *get_chained_signal_action(int sig);
   static bool chained_handler(int sig, siginfo_t *siginfo, void *context);
 
-  // The following allow us to link against both the old and new libthread (2.8)
-  // and exploit the new libthread functionality if available.
-
-  static bool T2_libthread()                                { return _T2_libthread; }
-  static void set_T2_libthread(bool T2_libthread) { _T2_libthread = T2_libthread; }
-
-  static int thr_getstate(thread_t tid, int *flag, unsigned *lwp, stack_t *ss, gregset_t rs)
-    { return _thr_getstate(tid, flag, lwp, ss, rs); }
-  static void set_thr_getstate(int_fnP_thread_t_iP_uP_stack_tP_gregset_t func)
-    { _thr_getstate = func; }
-
-  static int thr_setstate(thread_t tid, int flag, gregset_t rs)   { return _thr_setstate(tid, flag, rs); }
-  static void set_thr_setstate(int_fnP_thread_t_i_gregset_t func) { _thr_setstate = func; }
-
-  static int thr_setmutator(thread_t tid, int enabled)    { return _thr_setmutator(tid, enabled); }
-  static void set_thr_setmutator(int_fnP_thread_t_i func) { _thr_setmutator = func; }
-
-  static int  thr_suspend_mutator(thread_t tid)              { return _thr_suspend_mutator(tid); }
-  static void set_thr_suspend_mutator(int_fnP_thread_t func) { _thr_suspend_mutator = func; }
-
-  static int  thr_continue_mutator(thread_t tid)              { return _thr_continue_mutator(tid); }
-  static void set_thr_continue_mutator(int_fnP_thread_t func) { _thr_continue_mutator = func; }
-
   // Allows us to switch between lwp and thread -based synchronization
   static int mutex_lock(mutex_t *mx)    { return _mutex_lock(mx); }
   static int mutex_trylock(mutex_t *mx) { return _mutex_trylock(mx); }
--- a/hotspot/src/os/windows/vm/os_windows.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/windows/vm/os_windows.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -3520,7 +3520,7 @@
 
 void os::yield() {  os::NakedYield(); }
 
-void os::yield_all(int attempts) {
+void os::yield_all() {
   // Yields to all threads, including threads with lower priorities
   Sleep(1);
 }
@@ -3866,12 +3866,6 @@
   win32::setmode_streams();
   init_page_sizes((size_t) win32::vm_page_size());
 
-  // For better scalability on MP systems (must be called after initialize_system_info)
-#ifndef PRODUCT
-  if (is_MP()) {
-    NoYieldsInMicrolock = true;
-  }
-#endif
   // This may be overridden later when argument processing is done.
   FLAG_SET_ERGO(bool, UseLargePagesIndividualAllocation,
     os::win32::is_windows_2003());
--- a/hotspot/src/os/windows/vm/os_windows.inline.hpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os/windows/vm/os_windows.inline.hpp	Thu Apr 03 09:28:28 2014 +0000
@@ -52,9 +52,6 @@
   return (void*)::GetProcAddress((HMODULE)lib, name);
 }
 
-// Used to improve time-sharing on some systems
-inline void os::loop_breaker(int attempts) {}
-
 inline bool os::obsolete_option(const JavaVMOption *option) {
   return false;
 }
--- a/hotspot/src/os_cpu/solaris_sparc/vm/os_solaris_sparc.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os_cpu/solaris_sparc/vm/os_solaris_sparc.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -270,31 +270,6 @@
   }
 }
 
-static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {
-  char lwpstatusfile[PROCFILE_LENGTH];
-  int lwpfd, err;
-
-  if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))
-    return (err);
-  if (*flags == TRS_LWPID) {
-    sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),
-            *lwp);
-    if ((lwpfd = ::open(lwpstatusfile, O_RDONLY)) < 0) {
-      perror("thr_mutator_status: open lwpstatus");
-      return (EINVAL);
-    }
-    if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=
-        sizeof (lwpstatus_t)) {
-      perror("thr_mutator_status: read lwpstatus");
-      (void) ::close(lwpfd);
-      return (EINVAL);
-    }
-    (void) ::close(lwpfd);
-  }
-  return (0);
-}
-
-
 bool os::is_allocatable(size_t bytes) {
 #ifdef _LP64
    return true;
--- a/hotspot/src/os_cpu/solaris_x86/vm/os_solaris_x86.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/os_cpu/solaris_x86/vm/os_solaris_x86.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -256,30 +256,6 @@
   }
 }
 
-static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {
-  char lwpstatusfile[PROCFILE_LENGTH];
-  int lwpfd, err;
-
-  if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))
-    return (err);
-  if (*flags == TRS_LWPID) {
-    sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),
-            *lwp);
-    if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) {
-      perror("thr_mutator_status: open lwpstatus");
-      return (EINVAL);
-    }
-    if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=
-        sizeof (lwpstatus_t)) {
-      perror("thr_mutator_status: read lwpstatus");
-      (void) close(lwpfd);
-      return (EINVAL);
-    }
-    (void) close(lwpfd);
-  }
-  return (0);
-}
-
 #ifndef AMD64
 
 // Detecting SSE support by OS
--- a/hotspot/src/share/vm/runtime/arguments.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/share/vm/runtime/arguments.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -307,6 +307,9 @@
                            JDK_Version::jdk_update(7, 2), JDK_Version::jdk(8) },
 #endif // PRODUCT
   { "UseVMInterruptibleIO",          JDK_Version::jdk(8), JDK_Version::jdk(9) },
+  { "UseBoundThreads",               JDK_Version::jdk(9), JDK_Version::jdk(10) },
+  { "DefaultThreadPriority",         JDK_Version::jdk(9), JDK_Version::jdk(10) },
+  { "NoYieldsInMicrolock",           JDK_Version::jdk(9), JDK_Version::jdk(10) },
   { NULL, JDK_Version(0), JDK_Version(0) }
 };
 
@@ -2078,17 +2081,6 @@
   // Note: Needs platform-dependent factoring.
   bool status = true;
 
-  // Allow both -XX:-UseStackBanging and -XX:-UseBoundThreads in non-product
-  // builds so the cost of stack banging can be measured.
-#if (defined(PRODUCT) && defined(SOLARIS))
-  if (!UseBoundThreads && !UseStackBanging) {
-    jio_fprintf(defaultStream::error_stream(),
-                "-UseStackBanging conflicts with -UseBoundThreads\n");
-
-     status = false;
-  }
-#endif
-
   if (TLABRefillWasteFraction == 0) {
     jio_fprintf(defaultStream::error_stream(),
                 "TLABRefillWasteFraction should be a denominator, "
--- a/hotspot/src/share/vm/runtime/os.hpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/share/vm/runtime/os.hpp	Thu Apr 03 09:28:28 2014 +0000
@@ -450,8 +450,8 @@
     // yield that can be used in lieu of blocking.
   } ;
   static YieldResult NakedYield () ;
-  static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
-  static void loop_breaker(int attempts);  // called from within tight loops to possibly influence time-sharing
+  static void yield_all(); // Yields to all other threads including lower priority
+                           // (for the default scheduling policy)
   static OSReturn set_priority(Thread* thread, ThreadPriority priority);
   static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
 
--- a/hotspot/src/share/vm/runtime/safepoint.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/share/vm/runtime/safepoint.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -319,7 +319,7 @@
       if (steps < DeferThrSuspendLoopCount) {
         os::NakedYield() ;
       } else {
-        os::yield_all(steps) ;
+        os::yield_all() ;
         // Alternately, the VM thread could transiently depress its scheduling priority or
         // transiently increase the priority of the tardy mutator(s).
       }
--- a/hotspot/src/share/vm/runtime/sharedRuntime.cpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/share/vm/runtime/sharedRuntime.cpp	Thu Apr 03 09:28:28 2014 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -924,12 +924,6 @@
 JRT_END
 #endif // !PRODUCT
 
-
-JRT_ENTRY(void, SharedRuntime::yield_all(JavaThread* thread, int attempts))
-  os::yield_all(attempts);
-JRT_END
-
-
 JRT_ENTRY_NO_ASYNC(void, SharedRuntime::register_finalizer(JavaThread* thread, oopDesc* obj))
   assert(obj->is_oop(), "must be a valid oop");
   assert(obj->klass()->has_finalizer(), "shouldn't be here otherwise");
--- a/hotspot/src/share/vm/runtime/sharedRuntime.hpp	Wed Apr 02 16:08:59 2014 +0100
+++ b/hotspot/src/share/vm/runtime/sharedRuntime.hpp	Thu Apr 03 09:28:28 2014 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -253,9 +253,6 @@
   // bytecode tracing is only used by the TraceBytecodes
   static intptr_t trace_bytecode(JavaThread* thread, intptr_t preserve_this_value, intptr_t tos, intptr_t tos2) PRODUCT_RETURN0;
 
-  // Used to back off a spin lock that is under heavy contention
-  static void yield_all(JavaThread* thread, int attempts = 0);
-
   static oop retrieve_receiver( Symbol* sig, frame caller );
 
   static void register_finalizer(JavaThread* thread, oopDesc* obj);