--- a/hotspot/src/share/vm/oops/instanceKlass.cpp Mon Nov 02 15:52:37 2015 +0100
+++ b/hotspot/src/share/vm/oops/instanceKlass.cpp Wed Nov 18 03:03:43 2015 +0300
@@ -27,6 +27,7 @@
#include "classfile/systemDictionary.hpp"
#include "classfile/verifier.hpp"
#include "classfile/vmSymbols.hpp"
+#include "code/dependencyContext.hpp"
#include "compiler/compileBroker.hpp"
#include "gc/shared/collectedHeap.inline.hpp"
#include "gc/shared/specialized_oop_closures.hpp"
@@ -203,7 +204,6 @@
int iksize = InstanceKlass::size(vtable_len, itable_len, nonstatic_oop_map_size,
access_flags.is_interface(), is_anonymous);
-
set_vtable_length(vtable_len);
set_itable_length(itable_len);
set_static_field_size(static_field_size);
@@ -232,7 +232,7 @@
set_static_oop_field_count(0);
set_nonstatic_field_size(0);
set_is_marked_dependent(false);
- set_has_unloaded_dependent(false);
+ _dep_context = DependencyContext::EMPTY;
set_init_state(InstanceKlass::allocated);
set_init_thread(NULL);
set_reference_type(rt);
@@ -246,7 +246,6 @@
set_annotations(NULL);
set_jvmti_cached_class_field_map(NULL);
set_initial_method_idnum(0);
- _dependencies = NULL;
set_jvmti_cached_class_field_map(NULL);
set_cached_class_file(NULL);
set_initial_method_idnum(0);
@@ -1854,200 +1853,30 @@
return id;
}
-int nmethodBucket::decrement() {
- return Atomic::add(-1, (volatile int *)&_count);
-}
-
-//
-// Walk the list of dependent nmethods searching for nmethods which
-// are dependent on the changes that were passed in and mark them for
-// deoptimization. Returns the number of nmethods found.
-//
-int nmethodBucket::mark_dependent_nmethods(nmethodBucket* deps, DepChange& changes) {
- assert_locked_or_safepoint(CodeCache_lock);
- int found = 0;
- for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
- nmethod* nm = b->get_nmethod();
- // since dependencies aren't removed until an nmethod becomes a zombie,
- // the dependency list may contain nmethods which aren't alive.
- if (b->count() > 0 && nm->is_alive() && !nm->is_marked_for_deoptimization() && nm->check_dependency_on(changes)) {
- if (TraceDependencies) {
- ResourceMark rm;
- tty->print_cr("Marked for deoptimization");
- changes.print();
- nm->print();
- nm->print_dependencies();
- }
- nm->mark_for_deoptimization();
- found++;
- }
- }
- return found;
-}
-
-//
-// Add an nmethodBucket to the list of dependencies for this nmethod.
-// It's possible that an nmethod has multiple dependencies on this klass
-// so a count is kept for each bucket to guarantee that creation and
-// deletion of dependencies is consistent. Returns new head of the list.
-//
-nmethodBucket* nmethodBucket::add_dependent_nmethod(nmethodBucket* deps, nmethod* nm) {
- assert_locked_or_safepoint(CodeCache_lock);
- for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
- if (nm == b->get_nmethod()) {
- b->increment();
- return deps;
- }
- }
- return new nmethodBucket(nm, deps);
+inline DependencyContext InstanceKlass::dependencies() {
+ DependencyContext dep_context(&_dep_context);
+ return dep_context;
}
-//
-// Decrement count of the nmethod in the dependency list and remove
-// the bucket completely when the count goes to 0. This method must
-// find a corresponding bucket otherwise there's a bug in the
-// recording of dependencies. Returns true if the bucket was deleted,
-// or marked ready for reclaimation.
-bool nmethodBucket::remove_dependent_nmethod(nmethodBucket** deps, nmethod* nm, bool delete_immediately) {
- assert_locked_or_safepoint(CodeCache_lock);
-
- nmethodBucket* first = *deps;
- nmethodBucket* last = NULL;
-
- for (nmethodBucket* b = first; b != NULL; b = b->next()) {
- if (nm == b->get_nmethod()) {
- int val = b->decrement();
- guarantee(val >= 0, "Underflow: %d", val);
- if (val == 0) {
- if (delete_immediately) {
- if (last == NULL) {
- *deps = b->next();
- } else {
- last->set_next(b->next());
- }
- delete b;
- }
- }
- return true;
- }
- last = b;
- }
-
-#ifdef ASSERT
- tty->print_raw_cr("### can't find dependent nmethod");
- nm->print();
-#endif // ASSERT
- ShouldNotReachHere();
- return false;
-}
-
-// Convenience overload, for callers that don't want to delete the nmethodBucket entry.
-bool nmethodBucket::remove_dependent_nmethod(nmethodBucket* deps, nmethod* nm) {
- nmethodBucket** deps_addr = &deps;
- return remove_dependent_nmethod(deps_addr, nm, false /* Don't delete */);
-}
-
-//
-// Reclaim all unused buckets. Returns new head of the list.
-//
-nmethodBucket* nmethodBucket::clean_dependent_nmethods(nmethodBucket* deps) {
- nmethodBucket* first = deps;
- nmethodBucket* last = NULL;
- nmethodBucket* b = first;
-
- while (b != NULL) {
- assert(b->count() >= 0, "bucket count: %d", b->count());
- nmethodBucket* next = b->next();
- if (b->count() == 0) {
- if (last == NULL) {
- first = next;
- } else {
- last->set_next(next);
- }
- delete b;
- // last stays the same.
- } else {
- last = b;
- }
- b = next;
- }
- return first;
-}
-
-#ifndef PRODUCT
-void nmethodBucket::print_dependent_nmethods(nmethodBucket* deps, bool verbose) {
- int idx = 0;
- for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
- nmethod* nm = b->get_nmethod();
- tty->print("[%d] count=%d { ", idx++, b->count());
- if (!verbose) {
- nm->print_on(tty, "nmethod");
- tty->print_cr(" } ");
- } else {
- nm->print();
- nm->print_dependencies();
- tty->print_cr("--- } ");
- }
- }
-}
-
-bool nmethodBucket::is_dependent_nmethod(nmethodBucket* deps, nmethod* nm) {
- for (nmethodBucket* b = deps; b != NULL; b = b->next()) {
- if (nm == b->get_nmethod()) {
-#ifdef ASSERT
- int count = b->count();
- assert(count >= 0, "count shouldn't be negative: %d", count);
-#endif
- return true;
- }
- }
- return false;
-}
-#endif //PRODUCT
-
int InstanceKlass::mark_dependent_nmethods(DepChange& changes) {
- assert_locked_or_safepoint(CodeCache_lock);
- return nmethodBucket::mark_dependent_nmethods(_dependencies, changes);
-}
-
-void InstanceKlass::clean_dependent_nmethods() {
- assert_locked_or_safepoint(CodeCache_lock);
-
- if (has_unloaded_dependent()) {
- _dependencies = nmethodBucket::clean_dependent_nmethods(_dependencies);
- set_has_unloaded_dependent(false);
- }
-#ifdef ASSERT
- else {
- // Verification
- for (nmethodBucket* b = _dependencies; b != NULL; b = b->next()) {
- assert(b->count() >= 0, "bucket count: %d", b->count());
- assert(b->count() != 0, "empty buckets need to be cleaned");
- }
- }
-#endif
+ return dependencies().mark_dependent_nmethods(changes);
}
void InstanceKlass::add_dependent_nmethod(nmethod* nm) {
- assert_locked_or_safepoint(CodeCache_lock);
- _dependencies = nmethodBucket::add_dependent_nmethod(_dependencies, nm);
+ dependencies().add_dependent_nmethod(nm);
}
void InstanceKlass::remove_dependent_nmethod(nmethod* nm, bool delete_immediately) {
- assert_locked_or_safepoint(CodeCache_lock);
-
- if (nmethodBucket::remove_dependent_nmethod(&_dependencies, nm, delete_immediately)) {
- set_has_unloaded_dependent(true);
- }
+ dependencies().remove_dependent_nmethod(nm, delete_immediately);
}
#ifndef PRODUCT
void InstanceKlass::print_dependent_nmethods(bool verbose) {
- nmethodBucket::print_dependent_nmethods(_dependencies, verbose);
+ dependencies().print_dependent_nmethods(verbose);
}
bool InstanceKlass::is_dependent_nmethod(nmethod* nm) {
- return nmethodBucket::is_dependent_nmethod(_dependencies, nm);
+ return dependencies().is_dependent_nmethod(nm);
}
#endif //PRODUCT
@@ -2055,7 +1884,9 @@
clean_implementors_list(is_alive);
clean_method_data(is_alive);
- clean_dependent_nmethods();
+ // Since GC iterates InstanceKlasses sequentially, it is safe to remove stale entries here.
+ DependencyContext dep_context(&_dep_context);
+ dep_context.expunge_stale_entries();
}
void InstanceKlass::clean_implementors_list(BoolObjectClosure* is_alive) {
@@ -2102,6 +1933,8 @@
constants()->remove_unshareable_info();
+ assert(_dep_context == DependencyContext::EMPTY, "dependency context is not shareable");
+
for (int i = 0; i < methods()->length(); i++) {
Method* m = methods()->at(i);
m->remove_unshareable_info();
@@ -2231,12 +2064,10 @@
}
// release dependencies
- nmethodBucket* b = _dependencies;
- _dependencies = NULL;
- while (b != NULL) {
- nmethodBucket* next = b->next();
- delete b;
- b = next;
+ {
+ DependencyContext ctx(&_dep_context);
+ int marked = ctx.remove_all_dependents();
+ assert(marked == 0, "all dependencies should be already invalidated");
}
// Deallocate breakpoint records
@@ -3558,199 +3389,3 @@
unsigned char * InstanceKlass::get_cached_class_file_bytes() {
return VM_RedefineClasses::get_cached_class_file_bytes(_cached_class_file);
}
-
-
-/////////////// Unit tests ///////////////
-
-#ifndef PRODUCT
-
-class TestNmethodBucketContext {
- public:
- nmethod* _nmethodLast;
- nmethod* _nmethodMiddle;
- nmethod* _nmethodFirst;
-
- nmethodBucket* _bucketLast;
- nmethodBucket* _bucketMiddle;
- nmethodBucket* _bucketFirst;
-
- nmethodBucket* _bucketList;
-
- TestNmethodBucketContext() {
- CodeCache_lock->lock_without_safepoint_check();
-
- _nmethodLast = reinterpret_cast<nmethod*>(0x8 * 0);
- _nmethodMiddle = reinterpret_cast<nmethod*>(0x8 * 1);
- _nmethodFirst = reinterpret_cast<nmethod*>(0x8 * 2);
-
- _bucketLast = new nmethodBucket(_nmethodLast, NULL);
- _bucketMiddle = new nmethodBucket(_nmethodMiddle, _bucketLast);
- _bucketFirst = new nmethodBucket(_nmethodFirst, _bucketMiddle);
-
- _bucketList = _bucketFirst;
- }
-
- ~TestNmethodBucketContext() {
- delete _bucketLast;
- delete _bucketMiddle;
- delete _bucketFirst;
-
- CodeCache_lock->unlock();
- }
-};
-
-class TestNmethodBucket {
- public:
- static void testRemoveDependentNmethodFirstDeleteImmediately() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodFirst, true /* delete */);
-
- assert(c._bucketList == c._bucketMiddle, "check");
- assert(c._bucketList->next() == c._bucketLast, "check");
- assert(c._bucketList->next()->next() == NULL, "check");
-
- // Cleanup before context is deleted.
- c._bucketFirst = NULL;
- }
-
- static void testRemoveDependentNmethodMiddleDeleteImmediately() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodMiddle, true /* delete */);
-
- assert(c._bucketList == c._bucketFirst, "check");
- assert(c._bucketList->next() == c._bucketLast, "check");
- assert(c._bucketList->next()->next() == NULL, "check");
-
- // Cleanup before context is deleted.
- c._bucketMiddle = NULL;
- }
-
- static void testRemoveDependentNmethodLastDeleteImmediately() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodLast, true /* delete */);
-
- assert(c._bucketList == c._bucketFirst, "check");
- assert(c._bucketList->next() == c._bucketMiddle, "check");
- assert(c._bucketList->next()->next() == NULL, "check");
-
- // Cleanup before context is deleted.
- c._bucketLast = NULL;
- }
-
- static void testRemoveDependentNmethodFirstDeleteDeferred() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodFirst, false /* delete */);
-
- assert(c._bucketList == c._bucketFirst, "check");
- assert(c._bucketList->next() == c._bucketMiddle, "check");
- assert(c._bucketList->next()->next() == c._bucketLast, "check");
- assert(c._bucketList->next()->next()->next() == NULL, "check");
-
- assert(c._bucketFirst->count() == 0, "check");
- assert(c._bucketMiddle->count() == 1, "check");
- assert(c._bucketLast->count() == 1, "check");
- }
-
- static void testRemoveDependentNmethodMiddleDeleteDeferred() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodMiddle, false /* delete */);
-
- assert(c._bucketList == c._bucketFirst, "check");
- assert(c._bucketList->next() == c._bucketMiddle, "check");
- assert(c._bucketList->next()->next() == c._bucketLast, "check");
- assert(c._bucketList->next()->next()->next() == NULL, "check");
-
- assert(c._bucketFirst->count() == 1, "check");
- assert(c._bucketMiddle->count() == 0, "check");
- assert(c._bucketLast->count() == 1, "check");
- }
-
- static void testRemoveDependentNmethodLastDeleteDeferred() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(&c._bucketList, c._nmethodLast, false /* delete */);
-
- assert(c._bucketList == c._bucketFirst, "check");
- assert(c._bucketList->next() == c._bucketMiddle, "check");
- assert(c._bucketList->next()->next() == c._bucketLast, "check");
- assert(c._bucketList->next()->next()->next() == NULL, "check");
-
- assert(c._bucketFirst->count() == 1, "check");
- assert(c._bucketMiddle->count() == 1, "check");
- assert(c._bucketLast->count() == 0, "check");
- }
-
- static void testRemoveDependentNmethodConvenienceFirst() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodFirst);
-
- assert(c._bucketList == c._bucketFirst, "check");
- assert(c._bucketList->next() == c._bucketMiddle, "check");
- assert(c._bucketList->next()->next() == c._bucketLast, "check");
- assert(c._bucketList->next()->next()->next() == NULL, "check");
-
- assert(c._bucketFirst->count() == 0, "check");
- assert(c._bucketMiddle->count() == 1, "check");
- assert(c._bucketLast->count() == 1, "check");
- }
-
- static void testRemoveDependentNmethodConvenienceMiddle() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodMiddle);
-
- assert(c._bucketList == c._bucketFirst, "check");
- assert(c._bucketList->next() == c._bucketMiddle, "check");
- assert(c._bucketList->next()->next() == c._bucketLast, "check");
- assert(c._bucketList->next()->next()->next() == NULL, "check");
-
- assert(c._bucketFirst->count() == 1, "check");
- assert(c._bucketMiddle->count() == 0, "check");
- assert(c._bucketLast->count() == 1, "check");
- }
-
- static void testRemoveDependentNmethodConvenienceLast() {
- TestNmethodBucketContext c;
-
- nmethodBucket::remove_dependent_nmethod(c._bucketList, c._nmethodLast);
-
- assert(c._bucketList == c._bucketFirst, "check");
- assert(c._bucketList->next() == c._bucketMiddle, "check");
- assert(c._bucketList->next()->next() == c._bucketLast, "check");
- assert(c._bucketList->next()->next()->next() == NULL, "check");
-
- assert(c._bucketFirst->count() == 1, "check");
- assert(c._bucketMiddle->count() == 1, "check");
- assert(c._bucketLast->count() == 0, "check");
- }
-
- static void testRemoveDependentNmethod() {
- testRemoveDependentNmethodFirstDeleteImmediately();
- testRemoveDependentNmethodMiddleDeleteImmediately();
- testRemoveDependentNmethodLastDeleteImmediately();
-
- testRemoveDependentNmethodFirstDeleteDeferred();
- testRemoveDependentNmethodMiddleDeleteDeferred();
- testRemoveDependentNmethodLastDeleteDeferred();
-
- testRemoveDependentNmethodConvenienceFirst();
- testRemoveDependentNmethodConvenienceMiddle();
- testRemoveDependentNmethodConvenienceLast();
- }
-
- static void test() {
- testRemoveDependentNmethod();
- }
-};
-
-void TestNmethodBucket_test() {
- TestNmethodBucket::test();
-}
-
-#endif