Merge

15 files changed, 265 insertions, 162 deletions

diff --git a/src/share/vm/gc_implementation/g1/dirtyCardQueue.cpp b/src/share/vm/gc_implementation/g1/dirtyCardQueue.cpp
index 7bdb98f16..ddebcf530 100644
--- a/src/share/vm/gc_implementation/g1/dirtyCardQueue.cpp
+++ b/src/share/vm/gc_implementation/g1/dirtyCardQueue.cpp
@@ -24,6 +24,7 @@
 
 #include "precompiled.hpp"
 #include "gc_implementation/g1/dirtyCardQueue.hpp"
+#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
 #include "gc_implementation/g1/heapRegionRemSet.hpp"
 #include "runtime/atomic.hpp"
 #include "runtime/mutexLocker.hpp"
diff --git a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp
index c13eec974..f73eab90b 100644
--- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp
+++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp
@@ -3547,6 +3547,29 @@ public:
   }
 };
 
+bool G1CollectedHeap::is_obj_dead_cond(const oop obj,
+                                       const HeapRegion* hr,
+                                       const VerifyOption vo) const {
+  switch (vo) {
+  case VerifyOption_G1UsePrevMarking: return is_obj_dead(obj, hr);
+  case VerifyOption_G1UseNextMarking: return is_obj_ill(obj, hr);
+  case VerifyOption_G1UseMarkWord:    return !obj->is_gc_marked();
+  default:                            ShouldNotReachHere();
+  }
+  return false; // keep some compilers happy
+}
+
+bool G1CollectedHeap::is_obj_dead_cond(const oop obj,
+                                       const VerifyOption vo) const {
+  switch (vo) {
+  case VerifyOption_G1UsePrevMarking: return is_obj_dead(obj);
+  case VerifyOption_G1UseNextMarking: return is_obj_ill(obj);
+  case VerifyOption_G1UseMarkWord:    return !obj->is_gc_marked();
+  default:                            ShouldNotReachHere();
+  }
+  return false; // keep some compilers happy
+}
+
 void G1CollectedHeap::print_on(outputStream* st) const {
   st->print(" %-20s", "garbage-first heap");
   st->print(" total " SIZE_FORMAT "K, used " SIZE_FORMAT "K",
diff --git a/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp b/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp
index d50897d35..a18436eec 100644
--- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp
+++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp
@@ -706,19 +706,7 @@ public:
   // This is a fast test on whether a reference points into the
   // collection set or not. Assume that the reference
   // points into the heap.
-  bool in_cset_fast_test(oop obj) {
-    assert(_in_cset_fast_test != NULL, "sanity");
-    assert(_g1_committed.contains((HeapWord*) obj), err_msg("Given reference outside of heap, is "PTR_FORMAT, (HeapWord*)obj));
-    // no need to subtract the bottom of the heap from obj,
-    // _in_cset_fast_test is biased
-    uintx index = cast_from_oop<uintx>(obj) >> HeapRegion::LogOfHRGrainBytes;
-    bool ret = _in_cset_fast_test[index];
-    // let's make sure the result is consistent with what the slower
-    // test returns
-    assert( ret || !obj_in_cs(obj), "sanity");
-    assert(!ret ||  obj_in_cs(obj), "sanity");
-    return ret;
-  }
+  inline bool in_cset_fast_test(oop obj);
 
   void clear_cset_fast_test() {
     assert(_in_cset_fast_test_base != NULL, "sanity");
@@ -1264,9 +1252,7 @@ public:
     }
   }
 
-  void old_set_remove(HeapRegion* hr) {
-    _old_set.remove(hr);
-  }
+  inline void old_set_remove(HeapRegion* hr);
 
   size_t non_young_capacity_bytes() {
     return _old_set.total_capacity_bytes() + _humongous_set.total_capacity_bytes();
@@ -1357,7 +1343,7 @@ public:
   void heap_region_iterate(HeapRegionClosure* blk) const;
 
   // Return the region with the given index. It assumes the index is valid.
-  HeapRegion* region_at(uint index) const { return _hrs.at(index); }
+  inline HeapRegion* region_at(uint index) const;
 
   // Divide the heap region sequence into "chunks" of some size (the number
   // of regions divided by the number of parallel threads times some
@@ -1486,10 +1472,7 @@ public:
     return true;
   }
 
-  bool is_in_young(const oop obj) {
-    HeapRegion* hr = heap_region_containing(obj);
-    return hr != NULL && hr->is_young();
-  }
+  inline bool is_in_young(const oop obj);
 
 #ifdef ASSERT
   virtual bool is_in_partial_collection(const void* p);
@@ -1502,9 +1485,7 @@ public:
   // pre-value that needs to be remembered; for the remembered-set
   // update logging post-barrier, we don't maintain remembered set
   // information for young gen objects.
-  virtual bool can_elide_initializing_store_barrier(oop new_obj) {
-    return is_in_young(new_obj);
-  }
+  virtual inline bool can_elide_initializing_store_barrier(oop new_obj);
 
   // Returns "true" iff the given word_size is "very large".
   static bool isHumongous(size_t word_size) {
@@ -1598,23 +1579,9 @@ public:
 
   // Added if it is NULL it isn't dead.
 
-  bool is_obj_dead(const oop obj) const {
-    const HeapRegion* hr = heap_region_containing(obj);
-    if (hr == NULL) {
-      if (obj == NULL) return false;
-      else return true;
-    }
-    else return is_obj_dead(obj, hr);
-  }
+  inline bool is_obj_dead(const oop obj) const;
 
-  bool is_obj_ill(const oop obj) const {
-    const HeapRegion* hr = heap_region_containing(obj);
-    if (hr == NULL) {
-      if (obj == NULL) return false;
-      else return true;
-    }
-    else return is_obj_ill(obj, hr);
-  }
+  inline bool is_obj_ill(const oop obj) const;
 
   bool allocated_since_marking(oop obj, HeapRegion* hr, VerifyOption vo);
   HeapWord* top_at_mark_start(HeapRegion* hr, VerifyOption vo);
@@ -1708,26 +1675,10 @@ public:
 
   bool is_obj_dead_cond(const oop obj,
                         const HeapRegion* hr,
-                        const VerifyOption vo) const {
-    switch (vo) {
-    case VerifyOption_G1UsePrevMarking: return is_obj_dead(obj, hr);
-    case VerifyOption_G1UseNextMarking: return is_obj_ill(obj, hr);
-    case VerifyOption_G1UseMarkWord:    return !obj->is_gc_marked();
-    default:                            ShouldNotReachHere();
-    }
-    return false; // keep some compilers happy
-  }
+                        const VerifyOption vo) const;
 
   bool is_obj_dead_cond(const oop obj,
-                        const VerifyOption vo) const {
-    switch (vo) {
-    case VerifyOption_G1UsePrevMarking: return is_obj_dead(obj);
-    case VerifyOption_G1UseNextMarking: return is_obj_ill(obj);
-    case VerifyOption_G1UseMarkWord:    return !obj->is_gc_marked();
-    default:                            ShouldNotReachHere();
-    }
-    return false; // keep some compilers happy
-  }
+                        const VerifyOption vo) const;
 
   // Printing
 
@@ -1821,11 +1772,7 @@ protected:
   DirtyCardQueue& dirty_card_queue()             { return _dcq;  }
   G1SATBCardTableModRefBS* ctbs()                { return _ct_bs; }
 
-  template <class T> void immediate_rs_update(HeapRegion* from, T* p, int tid) {
-    if (!from->is_survivor()) {
-      _g1_rem->par_write_ref(from, p, tid);
-    }
-  }
+  template <class T> inline void immediate_rs_update(HeapRegion* from, T* p, int tid);
 
   template <class T> void deferred_rs_update(HeapRegion* from, T* p, int tid) {
     // If the new value of the field points to the same region or
@@ -1867,13 +1814,7 @@ public:
     refs()->push(ref);
   }
 
-  template <class T> void update_rs(HeapRegion* from, T* p, int tid) {
-    if (G1DeferredRSUpdate) {
-      deferred_rs_update(from, p, tid);
-    } else {
-      immediate_rs_update(from, p, tid);
-    }
-  }
+  template <class T> inline void update_rs(HeapRegion* from, T* p, int tid);
 
   HeapWord* allocate_slow(GCAllocPurpose purpose, size_t word_sz) {
     HeapWord* obj = NULL;
@@ -1997,54 +1938,7 @@ private:
     return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
   }
 
-  void do_oop_partial_array(oop* p) {
-    assert(has_partial_array_mask(p), "invariant");
-    oop from_obj = clear_partial_array_mask(p);
-
-    assert(Universe::heap()->is_in_reserved(from_obj), "must be in heap.");
-    assert(from_obj->is_objArray(), "must be obj array");
-    objArrayOop from_obj_array = objArrayOop(from_obj);
-    // The from-space object contains the real length.
-    int length                 = from_obj_array->length();
-
-    assert(from_obj->is_forwarded(), "must be forwarded");
-    oop to_obj                 = from_obj->forwardee();
-    assert(from_obj != to_obj, "should not be chunking self-forwarded objects");
-    objArrayOop to_obj_array   = objArrayOop(to_obj);
-    // We keep track of the next start index in the length field of the
-    // to-space object.
-    int next_index             = to_obj_array->length();
-    assert(0 <= next_index && next_index < length,
-           err_msg("invariant, next index: %d, length: %d", next_index, length));
-
-    int start                  = next_index;
-    int end                    = length;
-    int remainder              = end - start;
-    // We'll try not to push a range that's smaller than ParGCArrayScanChunk.
-    if (remainder > 2 * ParGCArrayScanChunk) {
-      end = start + ParGCArrayScanChunk;
-      to_obj_array->set_length(end);
-      // Push the remainder before we process the range in case another
-      // worker has run out of things to do and can steal it.
-      oop* from_obj_p = set_partial_array_mask(from_obj);
-      push_on_queue(from_obj_p);
-    } else {
-      assert(length == end, "sanity");
-      // We'll process the final range for this object. Restore the length
-      // so that the heap remains parsable in case of evacuation failure.
-      to_obj_array->set_length(end);
-    }
-    _scanner.set_region(_g1h->heap_region_containing_raw(to_obj));
-    // Process indexes [start,end). It will also process the header
-    // along with the first chunk (i.e., the chunk with start == 0).
-    // Note that at this point the length field of to_obj_array is not
-    // correct given that we are using it to keep track of the next
-    // start index. oop_iterate_range() (thankfully!) ignores the length
-    // field and only relies on the start / end parameters.  It does
-    // however return the size of the object which will be incorrect. So
-    // we have to ignore it even if we wanted to use it.
-    to_obj_array->oop_iterate_range(&_scanner, start, end);
-  }
+  inline void do_oop_partial_array(oop* p);
 
   // This method is applied to the fields of the objects that have just been copied.
   template <class T> void do_oop_evac(T* p, HeapRegion* from) {
@@ -2074,26 +1968,9 @@ public:
 
   oop copy_to_survivor_space(oop const obj);
 
-  template <class T> void deal_with_reference(T* ref_to_scan) {
-    if (!has_partial_array_mask(ref_to_scan)) {
-      // Note: we can use "raw" versions of "region_containing" because
-      // "obj_to_scan" is definitely in the heap, and is not in a
-      // humongous region.
-      HeapRegion* r = _g1h->heap_region_containing_raw(ref_to_scan);
-      do_oop_evac(ref_to_scan, r);
-    } else {
-      do_oop_partial_array((oop*)ref_to_scan);
-    }
-  }
+  template <class T> inline void deal_with_reference(T* ref_to_scan);
 
-  void deal_with_reference(StarTask ref) {
-    assert(verify_task(ref), "sanity");
-    if (ref.is_narrow()) {
-      deal_with_reference((narrowOop*)ref);
-    } else {
-      deal_with_reference((oop*)ref);
-    }
-  }
+  inline void deal_with_reference(StarTask ref);
 
 public:
   void trim_queue();
diff --git a/src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp b/src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp
index 91289d649..e3b8fd061 100644
--- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp
+++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp
@@ -29,6 +29,7 @@
 #include "gc_implementation/g1/g1CollectedHeap.hpp"
 #include "gc_implementation/g1/g1AllocRegion.inline.hpp"
 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
+#include "gc_implementation/g1/g1RemSet.inline.hpp"
 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
 #include "gc_implementation/g1/heapRegionSet.inline.hpp"
 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
@@ -36,6 +37,9 @@
 
 // Inline functions for G1CollectedHeap
 
+// Return the region with the given index. It assumes the index is valid.
+inline HeapRegion* G1CollectedHeap::region_at(uint index) const { return _hrs.at(index); }
+
 template <class T>
 inline HeapRegion*
 G1CollectedHeap::heap_region_containing(const T addr) const {
@@ -55,6 +59,10 @@ G1CollectedHeap::heap_region_containing_raw(const T addr) const {
   return res;
 }
 
+inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) {
+  _old_set.remove(hr);
+}
+
 inline bool G1CollectedHeap::obj_in_cs(oop obj) {
   HeapRegion* r = _hrs.addr_to_region((HeapWord*) obj);
   return r != NULL && r->in_collection_set();
@@ -151,6 +159,24 @@ inline bool G1CollectedHeap::isMarkedNext(oop obj) const {
   return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj);
 }
 
+
+// This is a fast test on whether a reference points into the
+// collection set or not. Assume that the reference
+// points into the heap.
+inline bool G1CollectedHeap::in_cset_fast_test(oop obj) {
+  assert(_in_cset_fast_test != NULL, "sanity");
+  assert(_g1_committed.contains((HeapWord*) obj), err_msg("Given reference outside of heap, is "PTR_FORMAT, (HeapWord*)obj));
+  // no need to subtract the bottom of the heap from obj,
+  // _in_cset_fast_test is biased
+  uintx index = cast_from_oop<uintx>(obj) >> HeapRegion::LogOfHRGrainBytes;
+  bool ret = _in_cset_fast_test[index];
+  // let's make sure the result is consistent with what the slower
+  // test returns
+  assert( ret || !obj_in_cs(obj), "sanity");
+  assert(!ret ||  obj_in_cs(obj), "sanity");
+  return ret;
+}
+
 #ifndef PRODUCT
 // Support for G1EvacuationFailureALot
 
@@ -224,4 +250,121 @@ inline void G1CollectedHeap::reset_evacuation_should_fail() {
 }
 #endif  // #ifndef PRODUCT
 
+inline bool G1CollectedHeap::is_in_young(const oop obj) {
+  HeapRegion* hr = heap_region_containing(obj);
+  return hr != NULL && hr->is_young();
+}
+
+// We don't need barriers for initializing stores to objects
+// in the young gen: for the SATB pre-barrier, there is no
+// pre-value that needs to be remembered; for the remembered-set
+// update logging post-barrier, we don't maintain remembered set
+// information for young gen objects.
+inline bool G1CollectedHeap::can_elide_initializing_store_barrier(oop new_obj) {
+  return is_in_young(new_obj);
+}
+
+inline bool G1CollectedHeap::is_obj_dead(const oop obj) const {
+  const HeapRegion* hr = heap_region_containing(obj);
+  if (hr == NULL) {
+    if (obj == NULL) return false;
+    else return true;
+  }
+  else return is_obj_dead(obj, hr);
+}
+
+inline bool G1CollectedHeap::is_obj_ill(const oop obj) const {
+  const HeapRegion* hr = heap_region_containing(obj);
+  if (hr == NULL) {
+    if (obj == NULL) return false;
+    else return true;
+  }
+  else return is_obj_ill(obj, hr);
+}
+
+template <class T> inline void G1ParScanThreadState::immediate_rs_update(HeapRegion* from, T* p, int tid) {
+  if (!from->is_survivor()) {
+    _g1_rem->par_write_ref(from, p, tid);
+  }
+}
+
+template <class T> void G1ParScanThreadState::update_rs(HeapRegion* from, T* p, int tid) {
+  if (G1DeferredRSUpdate) {
+    deferred_rs_update(from, p, tid);
+  } else {
+    immediate_rs_update(from, p, tid);
+  }
+}
+
+
+inline void G1ParScanThreadState::do_oop_partial_array(oop* p) {
+  assert(has_partial_array_mask(p), "invariant");
+  oop from_obj = clear_partial_array_mask(p);
+
+  assert(Universe::heap()->is_in_reserved(from_obj), "must be in heap.");
+  assert(from_obj->is_objArray(), "must be obj array");
+  objArrayOop from_obj_array = objArrayOop(from_obj);
+  // The from-space object contains the real length.
+  int length                 = from_obj_array->length();
+
+  assert(from_obj->is_forwarded(), "must be forwarded");
+  oop to_obj                 = from_obj->forwardee();
+  assert(from_obj != to_obj, "should not be chunking self-forwarded objects");
+  objArrayOop to_obj_array   = objArrayOop(to_obj);
+  // We keep track of the next start index in the length field of the
+  // to-space object.
+  int next_index             = to_obj_array->length();
+  assert(0 <= next_index && next_index < length,
+         err_msg("invariant, next index: %d, length: %d", next_index, length));
+
+  int start                  = next_index;
+  int end                    = length;
+  int remainder              = end - start;
+  // We'll try not to push a range that's smaller than ParGCArrayScanChunk.
+  if (remainder > 2 * ParGCArrayScanChunk) {
+    end = start + ParGCArrayScanChunk;
+    to_obj_array->set_length(end);
+    // Push the remainder before we process the range in case another
+    // worker has run out of things to do and can steal it.
+    oop* from_obj_p = set_partial_array_mask(from_obj);
+    push_on_queue(from_obj_p);
+  } else {
+    assert(length == end, "sanity");
+    // We'll process the final range for this object. Restore the length
+    // so that the heap remains parsable in case of evacuation failure.
+    to_obj_array->set_length(end);
+  }
+  _scanner.set_region(_g1h->heap_region_containing_raw(to_obj));
+  // Process indexes [start,end). It will also process the header
+  // along with the first chunk (i.e., the chunk with start == 0).
+  // Note that at this point the length field of to_obj_array is not
+  // correct given that we are using it to keep track of the next
+  // start index. oop_iterate_range() (thankfully!) ignores the length
+  // field and only relies on the start / end parameters.  It does
+  // however return the size of the object which will be incorrect. So
+  // we have to ignore it even if we wanted to use it.
+  to_obj_array->oop_iterate_range(&_scanner, start, end);
+}
+
+template <class T> inline void G1ParScanThreadState::deal_with_reference(T* ref_to_scan) {
+  if (!has_partial_array_mask(ref_to_scan)) {
+    // Note: we can use "raw" versions of "region_containing" because
+    // "obj_to_scan" is definitely in the heap, and is not in a
+    // humongous region.
+    HeapRegion* r = _g1h->heap_region_containing_raw(ref_to_scan);
+    do_oop_evac(ref_to_scan, r);
+  } else {
+    do_oop_partial_array((oop*)ref_to_scan);
+  }
+}
+
+inline void G1ParScanThreadState::deal_with_reference(StarTask ref) {
+  assert(verify_task(ref), "sanity");
+  if (ref.is_narrow()) {
+    deal_with_reference((narrowOop*)ref);
+  } else {
+    deal_with_reference((oop*)ref);
+  }
+}
+
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP
diff --git a/src/share/vm/gc_implementation/g1/sparsePRT.hpp b/src/share/vm/gc_implementation/g1/sparsePRT.hpp
index 86d5db162..5cc884621 100644
--- a/src/share/vm/gc_implementation/g1/sparsePRT.hpp
+++ b/src/share/vm/gc_implementation/g1/sparsePRT.hpp
@@ -25,7 +25,7 @@
 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_SPARSEPRT_HPP
 #define SHARE_VM_GC_IMPLEMENTATION_G1_SPARSEPRT_HPP
 
-#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
+#include "gc_implementation/g1/g1CollectedHeap.hpp"
 #include "gc_implementation/g1/heapRegion.hpp"
 #include "memory/allocation.hpp"
 #include "memory/cardTableModRefBS.hpp"
diff --git a/src/share/vm/prims/jni.cpp b/src/share/vm/prims/jni.cpp
index 6ee151006..eb7de64f4 100644
--- a/src/share/vm/prims/jni.cpp
+++ b/src/share/vm/prims/jni.cpp
@@ -5208,7 +5208,7 @@ _JNI_IMPORT_OR_EXPORT_ jint JNICALL JNI_CreateJavaVM(JavaVM **vm, void **penv, v
     }
 
 #ifndef PRODUCT
-  #ifndef TARGET_OS_FAMILY_windows
+  #ifndef CALL_TEST_FUNC_WITH_WRAPPER_IF_NEEDED
     #define CALL_TEST_FUNC_WITH_WRAPPER_IF_NEEDED(f) f()
   #endif
 
diff --git a/src/share/vm/runtime/arguments.cpp b/src/share/vm/runtime/arguments.cpp
index 9f28fc2f1..7441f2610 100644
--- a/src/share/vm/runtime/arguments.cpp
+++ b/src/share/vm/runtime/arguments.cpp
@@ -1880,24 +1880,22 @@ static bool verify_serial_gc_flags() {
 // check if do gclog rotation
 // +UseGCLogFileRotation is a must,
 // no gc log rotation when log file not supplied or
-// NumberOfGCLogFiles is 0, or GCLogFileSize is 0
+// NumberOfGCLogFiles is 0
 void check_gclog_consistency() {
   if (UseGCLogFileRotation) {
-    if ((Arguments::gc_log_filename() == NULL) ||
-        (NumberOfGCLogFiles == 0)  ||
-        (GCLogFileSize == 0)) {
+    if ((Arguments::gc_log_filename() == NULL) || (NumberOfGCLogFiles == 0)) {
       jio_fprintf(defaultStream::output_stream(),
-                  "To enable GC log rotation, use -Xloggc:<filename> -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=<num_of_files> -XX:GCLogFileSize=<num_of_size>[k|K|m|M|g|G]\n"
-                  "where num_of_file > 0 and num_of_size > 0\n"
+                  "To enable GC log rotation, use -Xloggc:<filename> -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=<num_of_files>\n"
+                  "where num_of_file > 0\n"
                   "GC log rotation is turned off\n");
       UseGCLogFileRotation = false;
     }
   }
 
-  if (UseGCLogFileRotation && GCLogFileSize < 8*K) {
-        FLAG_SET_CMDLINE(uintx, GCLogFileSize, 8*K);
-        jio_fprintf(defaultStream::output_stream(),
-                    "GCLogFileSize changed to minimum 8K\n");
+  if (UseGCLogFileRotation && (GCLogFileSize != 0) && (GCLogFileSize < 8*K)) {
+    FLAG_SET_CMDLINE(uintx, GCLogFileSize, 8*K);
+    jio_fprintf(defaultStream::output_stream(),
+                "GCLogFileSize changed to minimum 8K\n");
   }
 }
 
diff --git a/src/share/vm/runtime/globals.cpp b/src/share/vm/runtime/globals.cpp
index 74f7acdba..801f7b89a 100644
--- a/src/share/vm/runtime/globals.cpp
+++ b/src/share/vm/runtime/globals.cpp
@@ -325,7 +325,7 @@ void Flag::print_on(outputStream* st, bool withComments) {
     else st->print("%-16s", "");
   }
 
-  st->print("%-20");
+  st->print("%-20s", " ");
   print_kind(st);
 
   if (withComments) {
diff --git a/src/share/vm/runtime/globals.hpp b/src/share/vm/runtime/globals.hpp
index ff05111e9..9927eb79f 100644
--- a/src/share/vm/runtime/globals.hpp
+++ b/src/share/vm/runtime/globals.hpp
@@ -2422,9 +2422,9 @@ class CommandLineFlags {
           "Number of gclog files in rotation "                              \
           "(default: 0, no rotation)")                                      \
                                                                             \
-  product(uintx, GCLogFileSize, 0,                                          \
-          "GC log file size (default: 0 bytes, no rotation). "              \
-          "It requires UseGCLogFileRotation")                               \
+  product(uintx, GCLogFileSize, 8*K,                                        \
+          "GC log file size, requires UseGCLogFileRotation. "               \
+          "Set to 0 to only trigger rotation via jcmd")                     \
                                                                             \
   /* JVMTI heap profiling */                                                \
                                                                             \
diff --git a/src/share/vm/runtime/safepoint.cpp b/src/share/vm/runtime/safepoint.cpp
index 48e523f5a..cac23e97e 100644
--- a/src/share/vm/runtime/safepoint.cpp
+++ b/src/share/vm/runtime/safepoint.cpp
@@ -535,7 +535,7 @@ void SafepointSynchronize::do_cleanup_tasks() {
 
   // rotate log files?
   if (UseGCLogFileRotation) {
-    gclog_or_tty->rotate_log();
+    gclog_or_tty->rotate_log(false);
   }
 
   if (MemTracker::is_on()) {
diff --git a/src/share/vm/runtime/vm_operations.hpp b/src/share/vm/runtime/vm_operations.hpp
index ca616a52c..0cb3a18f9 100644
--- a/src/share/vm/runtime/vm_operations.hpp
+++ b/src/share/vm/runtime/vm_operations.hpp
@@ -94,6 +94,7 @@
   template(JFRCheckpoint)                         \
   template(Exit)                                  \
   template(LinuxDllLoad)                          \
+  template(RotateGCLog)                           \
 
 class VM_Operation: public CHeapObj<mtInternal> {
  public:
@@ -397,4 +398,15 @@ class VM_Exit: public VM_Operation {
   void doit();
 };
 
+
+class VM_RotateGCLog: public VM_Operation {
+ private:
+  outputStream* _out;
+
+ public:
+  VM_RotateGCLog(outputStream* st) : _out(st) {}
+  VMOp_Type type() const { return VMOp_RotateGCLog; }
+  void doit() { gclog_or_tty->rotate_log(true, _out); }
+};
+
 #endif // SHARE_VM_RUNTIME_VM_OPERATIONS_HPP
diff --git a/src/share/vm/services/diagnosticCommand.cpp b/src/share/vm/services/diagnosticCommand.cpp
index 71b552801..1245b5aaf 100644
--- a/src/share/vm/services/diagnosticCommand.cpp
+++ b/src/share/vm/services/diagnosticCommand.cpp
@@ -53,6 +53,7 @@ void DCmdRegistrant::register_dcmds(){
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ClassStatsDCmd>(full_export, true, false));
 #endif // INCLUDE_SERVICES
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ThreadDumpDCmd>(full_export, true, false));
+  DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<RotateGCLogDCmd>(full_export, true, false));
 
   // Enhanced JMX Agent Support
   // These commands won't be exported via the DiagnosticCommandMBean until an
@@ -650,3 +651,11 @@ void JMXStopRemoteDCmd::execute(DCmdSource source, TRAPS) {
     JavaCalls::call_static(&result, ik, vmSymbols::stopRemoteAgent_name(), vmSymbols::void_method_signature(), CHECK);
 }
 
+void RotateGCLogDCmd::execute(DCmdSource source, TRAPS) {
+  if (UseGCLogFileRotation) {
+    VM_RotateGCLog rotateop(output());
+    VMThread::execute(&rotateop);
+  } else {
+    output()->print_cr("Target VM does not support GC log file rotation.");
+  }
+}
diff --git a/src/share/vm/services/diagnosticCommand.hpp b/src/share/vm/services/diagnosticCommand.hpp
index 5485b119d..2ce410998 100644
--- a/src/share/vm/services/diagnosticCommand.hpp
+++ b/src/share/vm/services/diagnosticCommand.hpp
@@ -360,4 +360,21 @@ public:
   virtual void execute(DCmdSource source, TRAPS);
 };
 
+class RotateGCLogDCmd : public DCmd {
+public:
+  RotateGCLogDCmd(outputStream* output, bool heap) : DCmd(output, heap) {}
+  static const char* name() { return "GC.rotate_log"; }
+  static const char* description() {
+    return "Force the GC log file to be rotated.";
+  }
+  static const char* impact() { return "Low"; }
+  virtual void execute(DCmdSource source, TRAPS);
+  static int num_arguments() { return 0; }
+  static const JavaPermission permission() {
+    JavaPermission p = {"java.lang.management.ManagementPermission",
+                        "control", NULL};
+    return p;
+  }
+};
+
 #endif // SHARE_VM_SERVICES_DIAGNOSTICCOMMAND_HPP
diff --git a/src/share/vm/utilities/ostream.cpp b/src/share/vm/utilities/ostream.cpp
index 90b3559e4..e09dfccf1 100644
--- a/src/share/vm/utilities/ostream.cpp
+++ b/src/share/vm/utilities/ostream.cpp
@@ -662,13 +662,13 @@ void gcLogFileStream::write(const char* s, size_t len) {
 // write to gc log file at safepoint. If in future, changes made for mutator threads or
 // concurrent GC threads to run parallel with VMThread at safepoint, write and rotate_log
 // must be synchronized.
-void gcLogFileStream::rotate_log() {
+void gcLogFileStream::rotate_log(bool force, outputStream* out) {
   char time_msg[FILENAMEBUFLEN];
   char time_str[EXTRACHARLEN];
   char current_file_name[FILENAMEBUFLEN];
   char renamed_file_name[FILENAMEBUFLEN];
 
-  if (_bytes_written < (jlong)GCLogFileSize) {
+  if (!should_rotate(force)) {
     return;
   }
 
@@ -685,6 +685,11 @@ void gcLogFileStream::rotate_log() {
     jio_snprintf(time_msg, sizeof(time_msg), "File  %s rotated at %s\n",
                  _file_name, os::local_time_string((char *)time_str, sizeof(time_str)));
     write(time_msg, strlen(time_msg));
+
+    if (out != NULL) {
+      out->print(time_msg);
+    }
+
     dump_loggc_header();
     return;
   }
@@ -706,12 +711,18 @@ void gcLogFileStream::rotate_log() {
                  _file_name, _cur_file_num);
     jio_snprintf(current_file_name, filename_len + EXTRACHARLEN, "%s.%d" CURRENTAPPX,
                  _file_name, _cur_file_num);
-    jio_snprintf(time_msg, sizeof(time_msg), "%s GC log file has reached the"
-                           " maximum size. Saved as %s\n",
-                           os::local_time_string((char *)time_str, sizeof(time_str)),
-                           renamed_file_name);
+
+    const char* msg = force ? "GC log rotation request has been received."
+                            : "GC log file has reached the maximum size.";
+    jio_snprintf(time_msg, sizeof(time_msg), "%s %s Saved as %s\n",
+                     os::local_time_string((char *)time_str, sizeof(time_str)),
+                                                         msg, renamed_file_name);
     write(time_msg, strlen(time_msg));
 
+    if (out != NULL) {
+      out->print(time_msg);
+    }
+
     fclose(_file);
     _file = NULL;
 
@@ -752,6 +763,11 @@ void gcLogFileStream::rotate_log() {
                            os::local_time_string((char *)time_str, sizeof(time_str)),
                            current_file_name);
     write(time_msg, strlen(time_msg));
+
+    if (out != NULL) {
+      out->print(time_msg);
+    }
+
     dump_loggc_header();
     // remove the existing file
     if (access(current_file_name, F_OK) == 0) {
diff --git a/src/share/vm/utilities/ostream.hpp b/src/share/vm/utilities/ostream.hpp
index 20e6f30bf..b783787e0 100644
--- a/src/share/vm/utilities/ostream.hpp
+++ b/src/share/vm/utilities/ostream.hpp
@@ -115,7 +115,7 @@ class outputStream : public ResourceObj {
    // flushing
    virtual void flush() {}
    virtual void write(const char* str, size_t len) = 0;
-   virtual void rotate_log() {} // GC log rotation
+   virtual void rotate_log(bool force, outputStream* out = NULL) {} // GC log rotation
    virtual ~outputStream() {}   // close properly on deletion
 
    void dec_cr() { dec(); cr(); }
@@ -240,8 +240,15 @@ class gcLogFileStream : public fileStream {
   gcLogFileStream(const char* file_name);
   ~gcLogFileStream();
   virtual void write(const char* c, size_t len);
-  virtual void rotate_log();
+  virtual void rotate_log(bool force, outputStream* out = NULL);
   void dump_loggc_header();
+
+  /* If "force" sets true, force log file rotation from outside JVM */
+  bool should_rotate(bool force) {
+    return force ||
+             ((GCLogFileSize != 0) && ((uintx)_bytes_written >= GCLogFileSize));
+  }
+
 };
 
 #ifndef PRODUCT