diff -r 45a293a4b895 -r 82e95c562133 hotspot/src/share/vm/runtime/sharedRuntime.cpp --- a/hotspot/src/share/vm/runtime/sharedRuntime.cpp Mon Dec 09 10:03:39 2013 +0100 +++ b/hotspot/src/share/vm/runtime/sharedRuntime.cpp Fri Dec 06 12:11:51 2013 -0800 @@ -1178,12 +1178,12 @@ CodeBlob* caller_cb = caller_frame.cb(); guarantee(caller_cb != NULL && caller_cb->is_nmethod(), "must be called from nmethod"); nmethod* caller_nm = caller_cb->as_nmethod_or_null(); + // make sure caller is not getting deoptimized // and removed before we are done with it. // CLEANUP - with lazy deopt shouldn't need this lock nmethodLocker caller_lock(caller_nm); - // determine call info & receiver // note: a) receiver is NULL for static calls // b) an exception is thrown if receiver is NULL for non-static calls @@ -1198,6 +1198,11 @@ (!is_virtual && invoke_code == Bytecodes::_invokedynamic) || ( is_virtual && invoke_code != Bytecodes::_invokestatic ), "inconsistent bytecode"); + // We do not patch the call site if the caller nmethod has been made non-entrant. + if (!caller_nm->is_in_use()) { + return callee_method; + } + #ifndef PRODUCT // tracing/debugging/statistics int *addr = (is_optimized) ? (&_resolve_opt_virtual_ctr) : @@ -1237,6 +1242,10 @@ // Make sure the callee nmethod does not get deoptimized and removed before // we are done patching the code. nmethod* callee_nm = callee_method->code(); + if (callee_nm != NULL && !callee_nm->is_in_use()) { + // Patch call site to C2I adapter if callee nmethod is deoptimized or unloaded. + callee_nm = NULL; + } nmethodLocker nl_callee(callee_nm); #ifdef ASSERT address dest_entry_point = callee_nm == NULL ? 0 : callee_nm->entry_point(); // used below @@ -1258,15 +1267,24 @@ { MutexLocker ml_patch(CompiledIC_lock); + // Lock blocks for safepoint during which both nmethods can change state. + // Now that we are ready to patch if the Method* was redefined then // don't update call site and let the caller retry. - - if (!callee_method->is_old()) { + // Don't update call site if caller nmethod has been made non-entrant + // as it is a waste of time. + // Don't update call site if callee nmethod was unloaded or deoptimized. + // Don't update call site if callee nmethod was replaced by an other nmethod + // which may happen when multiply alive nmethod (tiered compilation) + // will be supported. + if (!callee_method->is_old() && caller_nm->is_in_use() && + (callee_nm == NULL || callee_nm->is_in_use() && (callee_method->code() == callee_nm))) { #ifdef ASSERT // We must not try to patch to jump to an already unloaded method. if (dest_entry_point != 0) { - assert(CodeCache::find_blob(dest_entry_point) != NULL, - "should not unload nmethod while locked"); + CodeBlob* cb = CodeCache::find_blob(dest_entry_point); + assert((cb != NULL) && cb->is_nmethod() && (((nmethod*)cb) == callee_nm), + "should not call unloaded nmethod"); } #endif if (is_virtual) {