1.1 --- a/src/share/vm/code/nmethod.cpp Thu Aug 22 09:39:54 2013 -0700
1.2 +++ b/src/share/vm/code/nmethod.cpp Thu Sep 05 11:04:39 2013 -0700
1.3 @@ -687,6 +687,7 @@
1.4 code_buffer->copy_values_to(this);
1.5 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
1.6 CodeCache::add_scavenge_root_nmethod(this);
1.7 + Universe::heap()->register_nmethod(this);
1.8 }
1.9 debug_only(verify_scavenge_root_oops());
1.10 CodeCache::commit(this);
1.11 @@ -881,6 +882,7 @@
1.12 dependencies->copy_to(this);
1.13 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
1.14 CodeCache::add_scavenge_root_nmethod(this);
1.15 + Universe::heap()->register_nmethod(this);
1.16 }
1.17 debug_only(verify_scavenge_root_oops());
1.18
1.19 @@ -1300,6 +1302,13 @@
1.20 methodHandle the_method(method());
1.21 No_Safepoint_Verifier nsv;
1.22
1.23 + // during patching, depending on the nmethod state we must notify the GC that
1.24 + // code has been unloaded, unregistering it. We cannot do this right while
1.25 + // holding the Patching_lock because we need to use the CodeCache_lock. This
1.26 + // would be prone to deadlocks.
1.27 + // This flag is used to remember whether we need to later lock and unregister.
1.28 + bool nmethod_needs_unregister = false;
1.29 +
1.30 {
1.31 // invalidate osr nmethod before acquiring the patching lock since
1.32 // they both acquire leaf locks and we don't want a deadlock.
1.33 @@ -1332,6 +1341,13 @@
1.34 inc_decompile_count();
1.35 }
1.36
1.37 + // If the state is becoming a zombie, signal to unregister the nmethod with
1.38 + // the heap.
1.39 + // This nmethod may have already been unloaded during a full GC.
1.40 + if ((state == zombie) && !is_unloaded()) {
1.41 + nmethod_needs_unregister = true;
1.42 + }
1.43 +
1.44 // Change state
1.45 _state = state;
1.46
1.47 @@ -1367,6 +1383,9 @@
1.48 // safepoint can sneak in, otherwise the oops used by the
1.49 // dependency logic could have become stale.
1.50 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1.51 + if (nmethod_needs_unregister) {
1.52 + Universe::heap()->unregister_nmethod(this);
1.53 + }
1.54 flush_dependencies(NULL);
1.55 }
1.56
1.57 @@ -1817,21 +1836,10 @@
1.58 if (_method != NULL) f(_method);
1.59 }
1.60
1.61 -
1.62 -// This method is called twice during GC -- once while
1.63 -// tracing the "active" nmethods on thread stacks during
1.64 -// the (strong) marking phase, and then again when walking
1.65 -// the code cache contents during the weak roots processing
1.66 -// phase. The two uses are distinguished by means of the
1.67 -// 'do_strong_roots_only' flag, which is true in the first
1.68 -// case. We want to walk the weak roots in the nmethod
1.69 -// only in the second case. The weak roots in the nmethod
1.70 -// are the oops in the ExceptionCache and the InlineCache
1.71 -// oops.
1.72 -void nmethod::oops_do(OopClosure* f, bool do_strong_roots_only) {
1.73 +void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1.74 // make sure the oops ready to receive visitors
1.75 - assert(!is_zombie() && !is_unloaded(),
1.76 - "should not call follow on zombie or unloaded nmethod");
1.77 + assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1.78 + assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1.79
1.80 // If the method is not entrant or zombie then a JMP is plastered over the
1.81 // first few bytes. If an oop in the old code was there, that oop
