--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/gc_implementation/parallelScavenge/psVirtualspace.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,371 @@
+/*
+ * Copyright 2003-2005 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.
+ *
+ */
+
+#include "incls/_precompiled.incl"
+#include "incls/_psVirtualspace.cpp.incl"
+
+// PSVirtualSpace
+
+PSVirtualSpace::PSVirtualSpace(ReservedSpace rs, size_t alignment) :
+  _alignment(alignment)
+{
+  set_reserved(rs);
+  set_committed(reserved_low_addr(), reserved_low_addr());
+  DEBUG_ONLY(verify());
+}
+
+PSVirtualSpace::PSVirtualSpace(ReservedSpace rs) :
+  _alignment(os::vm_page_size())
+{
+  set_reserved(rs);
+  set_committed(reserved_low_addr(), reserved_low_addr());
+  DEBUG_ONLY(verify());
+}
+
+// Deprecated.
+PSVirtualSpace::PSVirtualSpace(): _alignment(os::vm_page_size()) {
+}
+
+// Deprecated.
+bool PSVirtualSpace::initialize(ReservedSpace rs,
+                                size_t commit_size) {
+  set_reserved(rs);
+  set_committed(reserved_low_addr(), reserved_low_addr());
+
+  // Commit to initial size.
+  assert(commit_size <= rs.size(), "commit_size too big");
+  bool result = commit_size > 0 ? expand_by(commit_size) : true;
+  DEBUG_ONLY(verify());
+  return result;
+}
+
+PSVirtualSpace::~PSVirtualSpace() {
+  release();
+}
+
+bool PSVirtualSpace::contains(void* p) const {
+  char* const cp = (char*)p;
+  return cp >= committed_low_addr() && cp < committed_high_addr();
+}
+
+void PSVirtualSpace::release() {
+  DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this));
+  if (reserved_low_addr() != NULL) {
+    if (special()) {
+      os::release_memory_special(reserved_low_addr(), reserved_size());
+    } else {
+      (void)os::release_memory(reserved_low_addr(), reserved_size());
+    }
+  }
+  _reserved_low_addr = _reserved_high_addr = NULL;
+  _committed_low_addr = _committed_high_addr = NULL;
+  _special = false;
+}
+
+bool PSVirtualSpace::expand_by(size_t bytes, bool pre_touch) {
+  assert(is_aligned(bytes), "arg not aligned");
+  DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this));
+
+  if (uncommitted_size() < bytes) {
+    return false;
+  }
+
+  char* const base_addr = committed_high_addr();
+  bool result = special() || os::commit_memory(base_addr, bytes, alignment());
+  if (result) {
+    _committed_high_addr += bytes;
+  }
+
+  if (pre_touch || AlwaysPreTouch) {
+    for (char* curr = base_addr;
+         curr < _committed_high_addr;
+         curr += os::vm_page_size()) {
+      char tmp = *curr;
+      *curr = 0;
+    }
+  }
+
+  return result;
+}
+
+bool PSVirtualSpace::shrink_by(size_t bytes) {
+  assert(is_aligned(bytes), "arg not aligned");
+  DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this));
+
+  if (committed_size() < bytes) {
+    return false;
+  }
+
+  char* const base_addr = committed_high_addr() - bytes;
+  bool result = special() || os::uncommit_memory(base_addr, bytes);
+  if (result) {
+    _committed_high_addr -= bytes;
+  }
+
+  return result;
+}
+
+size_t
+PSVirtualSpace::expand_into(PSVirtualSpace* other_space, size_t bytes) {
+  assert(is_aligned(bytes), "arg not aligned");
+  assert(grows_up(), "this space must grow up");
+  assert(other_space->grows_down(), "other space must grow down");
+  assert(reserved_high_addr() == other_space->reserved_low_addr(),
+         "spaces not contiguous");
+  assert(special() == other_space->special(), "one space is special, the other is not");
+  DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this));
+  DEBUG_ONLY(PSVirtualSpaceVerifier other_verifier(other_space));
+
+  size_t bytes_needed = bytes;
+
+  // First use the uncommitted region in this space.
+  size_t tmp_bytes = MIN2(uncommitted_size(), bytes_needed);
+  if (tmp_bytes > 0) {
+    if (expand_by(tmp_bytes)) {
+      bytes_needed -= tmp_bytes;
+    } else {
+      return 0;
+    }
+  }
+
+  // Next take from the uncommitted region in the other space, and commit it.
+  tmp_bytes = MIN2(other_space->uncommitted_size(), bytes_needed);
+  if (tmp_bytes > 0) {
+    char* const commit_base = committed_high_addr();
+    if (other_space->special() ||
+        os::commit_memory(commit_base, tmp_bytes, alignment())) {
+      // Reduce the reserved region in the other space.
+      other_space->set_reserved(other_space->reserved_low_addr() + tmp_bytes,
+                                other_space->reserved_high_addr(),
+                                other_space->special());
+
+      // Grow both reserved and committed in this space.
+      _reserved_high_addr += tmp_bytes;
+      _committed_high_addr += tmp_bytes;
+      bytes_needed -= tmp_bytes;
+    } else {
+      return bytes - bytes_needed;
+    }
+  }
+
+  // Finally take from the already committed region in the other space.
+  tmp_bytes = bytes_needed;
+  if (tmp_bytes > 0) {
+    // Reduce both committed and reserved in the other space.
+    other_space->set_committed(other_space->committed_low_addr() + tmp_bytes,
+                               other_space->committed_high_addr());
+    other_space->set_reserved(other_space->reserved_low_addr() + tmp_bytes,
+                              other_space->reserved_high_addr(),
+                              other_space->special());
+
+    // Grow both reserved and committed in this space.
+    _reserved_high_addr += tmp_bytes;
+    _committed_high_addr += tmp_bytes;
+  }
+
+  return bytes;
+}
+
+#ifndef PRODUCT
+bool PSVirtualSpace::is_aligned(size_t value, size_t align) {
+  const size_t tmp_value = value + align - 1;
+  const size_t mask = ~(align - 1);
+  return (tmp_value & mask) == value;
+}
+
+bool PSVirtualSpace::is_aligned(size_t value) const {
+  return is_aligned(value, alignment());
+}
+
+bool PSVirtualSpace::is_aligned(char* value) const {
+  return is_aligned((size_t)value);
+}
+
+void PSVirtualSpace::verify() const {
+  assert(is_aligned(alignment(), os::vm_page_size()), "bad alignment");
+  assert(is_aligned(reserved_low_addr()), "bad reserved_low_addr");
+  assert(is_aligned(reserved_high_addr()), "bad reserved_high_addr");
+  assert(is_aligned(committed_low_addr()), "bad committed_low_addr");
+  assert(is_aligned(committed_high_addr()), "bad committed_high_addr");
+
+  // Reserved region must be non-empty or both addrs must be 0.
+  assert(reserved_low_addr() < reserved_high_addr() ||
+         reserved_low_addr() == NULL && reserved_high_addr() == NULL,
+         "bad reserved addrs");
+  assert(committed_low_addr() <= committed_high_addr(), "bad committed addrs");
+
+  if (grows_up()) {
+    assert(reserved_low_addr() == committed_low_addr(), "bad low addrs");
+    assert(reserved_high_addr() >= committed_high_addr(), "bad high addrs");
+  } else {
+    assert(reserved_high_addr() == committed_high_addr(), "bad high addrs");
+    assert(reserved_low_addr() <= committed_low_addr(), "bad low addrs");
+  }
+}
+
+void PSVirtualSpace::print() const {
+  gclog_or_tty->print_cr("virtual space [" PTR_FORMAT "]:  alignment="
+                         SIZE_FORMAT "K grows %s%s",
+                         this, alignment() / K, grows_up() ? "up" : "down",
+                         special() ? " (pinned in memory)" : "");
+  gclog_or_tty->print_cr("    reserved=" SIZE_FORMAT "K"
+                         " [" PTR_FORMAT "," PTR_FORMAT "]"
+                         " committed=" SIZE_FORMAT "K"
+                         " [" PTR_FORMAT "," PTR_FORMAT "]",
+                         reserved_size() / K,
+                         reserved_low_addr(), reserved_high_addr(),
+                         committed_size() / K,
+                         committed_low_addr(), committed_high_addr());
+}
+#endif // #ifndef PRODUCT
+
+void PSVirtualSpace::print_space_boundaries_on(outputStream* st) const {
+  st->print_cr(" [" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT ")",
+               low_boundary(), high(), high_boundary());
+}
+
+PSVirtualSpaceHighToLow::PSVirtualSpaceHighToLow(ReservedSpace rs,
+                                                 size_t alignment) :
+  PSVirtualSpace(alignment)
+{
+  set_reserved(rs);
+  set_committed(reserved_high_addr(), reserved_high_addr());
+  DEBUG_ONLY(verify());
+}
+
+PSVirtualSpaceHighToLow::PSVirtualSpaceHighToLow(ReservedSpace rs) {
+  set_reserved(rs);
+  set_committed(reserved_high_addr(), reserved_high_addr());
+  DEBUG_ONLY(verify());
+}
+
+bool PSVirtualSpaceHighToLow::expand_by(size_t bytes, bool pre_touch) {
+  assert(is_aligned(bytes), "arg not aligned");
+  DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this));
+
+  if (uncommitted_size() < bytes) {
+    return false;
+  }
+
+  char* const base_addr = committed_low_addr() - bytes;
+  bool result = special() || os::commit_memory(base_addr, bytes, alignment());
+  if (result) {
+    _committed_low_addr -= bytes;
+  }
+
+  if (pre_touch || AlwaysPreTouch) {
+    for (char* curr = base_addr;
+         curr < _committed_high_addr;
+         curr += os::vm_page_size()) {
+      char tmp = *curr;
+      *curr = 0;
+    }
+  }
+
+  return result;
+}
+
+bool PSVirtualSpaceHighToLow::shrink_by(size_t bytes) {
+  assert(is_aligned(bytes), "arg not aligned");
+  DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this));
+
+  if (committed_size() < bytes) {
+    return false;
+  }
+
+  char* const base_addr = committed_low_addr();
+  bool result = special() || os::uncommit_memory(base_addr, bytes);
+  if (result) {
+    _committed_low_addr += bytes;
+  }
+
+  return result;
+}
+
+size_t PSVirtualSpaceHighToLow::expand_into(PSVirtualSpace* other_space,
+                                            size_t bytes) {
+  assert(is_aligned(bytes), "arg not aligned");
+  assert(grows_down(), "this space must grow down");
+  assert(other_space->grows_up(), "other space must grow up");
+  assert(reserved_low_addr() == other_space->reserved_high_addr(),
+         "spaces not contiguous");
+  assert(special() == other_space->special(), "one space is special in memory, the other is not");
+  DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this));
+  DEBUG_ONLY(PSVirtualSpaceVerifier other_verifier(other_space));
+
+  size_t bytes_needed = bytes;
+
+  // First use the uncommitted region in this space.
+  size_t tmp_bytes = MIN2(uncommitted_size(), bytes_needed);
+  if (tmp_bytes > 0) {
+    if (expand_by(tmp_bytes)) {
+      bytes_needed -= tmp_bytes;
+    } else {
+      return 0;
+    }
+  }
+
+  // Next take from the uncommitted region in the other space, and commit it.
+  tmp_bytes = MIN2(other_space->uncommitted_size(), bytes_needed);
+  if (tmp_bytes > 0) {
+    char* const commit_base = committed_low_addr() - tmp_bytes;
+    if (other_space->special() ||
+        os::commit_memory(commit_base, tmp_bytes, alignment())) {
+      // Reduce the reserved region in the other space.
+      other_space->set_reserved(other_space->reserved_low_addr(),
+                                other_space->reserved_high_addr() - tmp_bytes,
+                                other_space->special());
+
+      // Grow both reserved and committed in this space.
+      _reserved_low_addr -= tmp_bytes;
+      _committed_low_addr -= tmp_bytes;
+      bytes_needed -= tmp_bytes;
+    } else {
+      return bytes - bytes_needed;
+    }
+  }
+
+  // Finally take from the already committed region in the other space.
+  tmp_bytes = bytes_needed;
+  if (tmp_bytes > 0) {
+    // Reduce both committed and reserved in the other space.
+    other_space->set_committed(other_space->committed_low_addr(),
+                               other_space->committed_high_addr() - tmp_bytes);
+    other_space->set_reserved(other_space->reserved_low_addr(),
+                              other_space->reserved_high_addr() - tmp_bytes,
+                              other_space->special());
+
+    // Grow both reserved and committed in this space.
+    _reserved_low_addr -= tmp_bytes;
+    _committed_low_addr -= tmp_bytes;
+  }
+
+  return bytes;
+}
+
+void
+PSVirtualSpaceHighToLow::print_space_boundaries_on(outputStream* st) const {
+  st->print_cr(" (" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT "]",
+               high_boundary(), low(), low_boundary());
+}