--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/os/solaris/vm/osThread_solaris.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,224 @@
+/*
+ * Copyright 1998-2006 Sun Microsystems, Inc.  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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+// do not include  precompiled  header file
+# include "incls/_osThread_solaris.cpp.incl"
+# include <signal.h>
+
+ // ***************************************************************
+ // Platform dependent initialization and cleanup
+ // ***************************************************************
+
+void OSThread::pd_initialize() {
+  _thread_id                         = 0;
+  sigemptyset(&_caller_sigmask);
+
+  _current_callback                  = NULL;
+  _current_callback_lock = VM_Version::supports_compare_and_exchange() ? NULL
+                    : new Mutex(Mutex::suspend_resume, "Callback_lock", true);
+
+  _saved_interrupt_thread_state      = _thread_new;
+  _vm_created_thread                 = false;
+}
+
+void OSThread::pd_destroy() {
+}
+
+// Synchronous interrupt support
+//
+// _current_callback == NULL          no pending callback
+//                   == 1             callback_in_progress
+//                   == other value   pointer to the pending callback
+//
+
+// CAS on v8 is implemented by using a global atomic_memory_operation_lock,
+// which is shared by other atomic functions. It is OK for normal uses, but
+// dangerous if used after some thread is suspended or if used in signal
+// handlers. Instead here we use a special per-thread lock to synchronize
+// updating _current_callback if we are running on v8. Note in general trying
+// to grab locks after a thread is suspended is not safe, but it is safe for
+// updating _current_callback, because synchronous interrupt callbacks are
+// currently only used in:
+// 1. GetThreadPC_Callback - used by WatcherThread to profile VM thread
+// There is no overlap between the callbacks, which means we won't try to
+// grab a thread's sync lock after the thread has been suspended while holding
+// the same lock.
+
+// used after a thread is suspended
+static intptr_t compare_and_exchange_current_callback (
+       intptr_t callback, intptr_t *addr, intptr_t compare_value, Mutex *sync) {
+  if (VM_Version::supports_compare_and_exchange()) {
+     return Atomic::cmpxchg_ptr(callback, addr, compare_value);
+  } else {
+     MutexLockerEx(sync, Mutex::_no_safepoint_check_flag);
+     if (*addr == compare_value) {
+       *addr = callback;
+       return compare_value;
+     } else {
+       return callback;
+     }
+  }
+}
+
+// used in signal handler
+static intptr_t exchange_current_callback(intptr_t callback, intptr_t *addr, Mutex *sync) {
+  if (VM_Version::supports_compare_and_exchange()) {
+    return Atomic::xchg_ptr(callback, addr);
+  } else {
+    MutexLockerEx(sync, Mutex::_no_safepoint_check_flag);
+    intptr_t cb = *addr;
+    *addr = callback;
+    return cb;
+  }
+}
+
+// one interrupt at a time. spin if _current_callback != NULL
+int OSThread::set_interrupt_callback(Sync_Interrupt_Callback * cb) {
+  int count = 0;
+  while (compare_and_exchange_current_callback(
+         (intptr_t)cb, (intptr_t *)&_current_callback, (intptr_t)NULL, _current_callback_lock) != NULL) {
+    while (_current_callback != NULL) {
+      count++;
+#ifdef ASSERT
+      if ((WarnOnStalledSpinLock > 0) &&
+          (count % WarnOnStalledSpinLock == 0)) {
+          warning("_current_callback seems to be stalled: %p", _current_callback);
+      }
+#endif
+      os::yield_all(count);
+    }
+  }
+  return 0;
+}
+
+// reset _current_callback, spin if _current_callback is callback_in_progress
+void OSThread::remove_interrupt_callback(Sync_Interrupt_Callback * cb) {
+  int count = 0;
+  while (compare_and_exchange_current_callback(
+         (intptr_t)NULL, (intptr_t *)&_current_callback, (intptr_t)cb, _current_callback_lock) != (intptr_t)cb) {
+#ifdef ASSERT
+    intptr_t p = (intptr_t)_current_callback;
+    assert(p == (intptr_t)callback_in_progress ||
+           p == (intptr_t)cb, "wrong _current_callback value");
+#endif
+    while (_current_callback != cb) {
+      count++;
+#ifdef ASSERT
+      if ((WarnOnStalledSpinLock > 0) &&
+          (count % WarnOnStalledSpinLock == 0)) {
+          warning("_current_callback seems to be stalled: %p", _current_callback);
+      }
+#endif
+      os::yield_all(count);
+    }
+  }
+}
+
+void OSThread::do_interrupt_callbacks_at_interrupt(InterruptArguments *args) {
+  Sync_Interrupt_Callback * cb;
+  cb = (Sync_Interrupt_Callback *)exchange_current_callback(
+        (intptr_t)callback_in_progress, (intptr_t *)&_current_callback, _current_callback_lock);
+
+  if (cb == NULL) {
+    // signal is delivered too late (thread is masking interrupt signal??).
+    // there is nothing we need to do because requesting thread has given up.
+  } else if ((intptr_t)cb == (intptr_t)callback_in_progress) {
+    fatal("invalid _current_callback state");
+  } else {
+    assert(cb->target()->osthread() == this, "wrong target");
+    cb->execute(args);
+    cb->leave_callback();             // notify the requester
+  }
+
+  // restore original _current_callback value
+  intptr_t p;
+  p = exchange_current_callback((intptr_t)cb, (intptr_t *)&_current_callback, _current_callback_lock);
+  assert(p == (intptr_t)callback_in_progress, "just checking");
+}
+
+// Called by the requesting thread to send a signal to target thread and
+// execute "this" callback from the signal handler.
+int OSThread::Sync_Interrupt_Callback::interrupt(Thread * target, int timeout) {
+  // Let signals to the vm_thread go even if the Threads_lock is not acquired
+  assert(Threads_lock->owned_by_self() || (target == VMThread::vm_thread()),
+         "must have threads lock to call this");
+
+  OSThread * osthread = target->osthread();
+
+  // may block if target thread already has a pending callback
+  osthread->set_interrupt_callback(this);
+
+  _target = target;
+
+  int rslt = thr_kill(osthread->thread_id(), os::Solaris::SIGasync());
+  assert(rslt == 0, "thr_kill != 0");
+
+  bool status = false;
+  jlong t1 = os::javaTimeMillis();
+  { // don't use safepoint check because we might be the watcher thread.
+    MutexLockerEx ml(_sync, Mutex::_no_safepoint_check_flag);
+    while (!is_done()) {
+      status = _sync->wait(Mutex::_no_safepoint_check_flag, timeout);
+
+      // status == true if timed out
+      if (status) break;
+
+      // update timeout
+      jlong t2 = os::javaTimeMillis();
+      timeout -= t2 - t1;
+      t1 = t2;
+    }
+  }
+
+  // reset current_callback
+  osthread->remove_interrupt_callback(this);
+
+  return status;
+}
+
+void OSThread::Sync_Interrupt_Callback::leave_callback() {
+  if (!_sync->owned_by_self()) {
+    // notify requesting thread
+    MutexLockerEx ml(_sync, Mutex::_no_safepoint_check_flag);
+    _is_done = true;
+    _sync->notify_all();
+  } else {
+    // Current thread is interrupted while it is holding the _sync lock, trying
+    // to grab it again will deadlock. The requester will timeout anyway,
+    // so just return.
+    _is_done = true;
+  }
+}
+
+// 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
+  }
+}