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view src/share/vm/runtime/vmStructs.hpp @ 3769:ef2d1b8f2dd4
7051430: CMS: ongoing CMS cycle should terminate abruptly to allow prompt JVM termination at exit
Summary: It turns out that there is no need to explicitly stop CMS since the JVM is taken down at a terminal safepoint during which CMS threads are (terminally) inactive. This will need to be revised if and when we evolve in the future to a point where we allow JVM reincarnation in the same process, but those changes will be much more sweeping than just terminating CMS threads. The unused ::stop() methods will be removed in a separate CR. Also include in this CR is the fix for a small typo in the spelling of UseGCLogFileRotation in a message in arguments.cpp, brought to our attention by Rainer Jung and reviewed by minqi.
Reviewed-by: johnc, jwilhelm
author | ysr |
---|---|
date | Mon, 13 Jun 2011 09:58:16 -0700 |
parents | 1d1603768966 |
children | da91efe96a93 |
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/* * Copyright (c) 2000, 2011, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_RUNTIME_VMSTRUCTS_HPP #define SHARE_VM_RUNTIME_VMSTRUCTS_HPP #ifndef VM_STRUCTS_KERNEL #include "utilities/debug.hpp" #endif #ifdef COMPILER1 #include "c1/c1_Runtime1.hpp" #endif // This table encapsulates the debugging information required by the // serviceability agent in order to run. Specifically, we need to // understand the layout of certain C data structures (offsets, in // bytes, of their fields.) // // There are alternatives for the design of this mechanism, including // parsing platform-specific debugging symbols from a debug build into // a program database. While this current mechanism can be considered // to be a workaround for the inability to debug arbitrary C and C++ // programs at the present time, it does have certain advantages. // First, it is platform-independent, which will vastly simplify the // initial bringup of the system both now and on future platforms. // Second, it is embedded within the VM, as opposed to being in a // separate program database; experience has shown that whenever // portions of a system are decoupled, version skew is problematic. // Third, generating a program database, for example for a product // build, would probably require two builds to be done: the desired // product build as well as an intermediary build with the PRODUCT // flag turned on but also compiled with -g, leading to a doubling of // the time required to get a serviceability agent-debuggable product // build. Fourth, and very significantly, this table probably // preserves more information about field types than stabs do; for // example, it preserves the fact that a field is a "jlong" rather // than transforming the type according to the typedef in jni_md.h, // which allows the Java-side code to identify "Java-sized" fields in // C++ data structures. If the symbol parsing mechanism was redone // using stabs, it might still be necessary to have a table somewhere // containing this information. // // Do not change the sizes or signedness of the integer values in // these data structures; they are fixed over in the serviceability // agent's Java code (for bootstrapping). typedef struct { const char* typeName; // The type name containing the given field (example: "Klass") const char* fieldName; // The field name within the type (example: "_name") const char* typeString; // Quoted name of the type of this field (example: "Symbol*"; // parsed in Java to ensure type correctness int32_t isStatic; // Indicates whether following field is an offset or an address uint64_t offset; // Offset of field within structure; only used for nonstatic fields void* address; // Address of field; only used for static fields // ("offset" can not be reused because of apparent SparcWorks compiler bug // in generation of initializer data) } VMStructEntry; typedef struct { const char* typeName; // Type name (example: "methodOopDesc") const char* superclassName; // Superclass name, or null if none (example: "oopDesc") int32_t isOopType; // Does this type represent an oop typedef? (i.e., "methodOop" or // "klassOop", but NOT "methodOopDesc") int32_t isIntegerType; // Does this type represent an integer type (of arbitrary size)? int32_t isUnsigned; // If so, is it unsigned? uint64_t size; // Size, in bytes, of the type } VMTypeEntry; typedef struct { const char* name; // Name of constant (example: "_thread_in_native") int32_t value; // Value of constant } VMIntConstantEntry; typedef struct { const char* name; // Name of constant (example: "_thread_in_native") uint64_t value; // Value of constant } VMLongConstantEntry; // This class is a friend of most classes, to be able to access // private fields class VMStructs { public: // The last entry is identified over in the serviceability agent by // the fact that it has a NULL fieldName static VMStructEntry localHotSpotVMStructs[]; // The last entry is identified over in the serviceability agent by // the fact that it has a NULL typeName static VMTypeEntry localHotSpotVMTypes[]; // Table of integer constants required by the serviceability agent. // The last entry is identified over in the serviceability agent by // the fact that it has a NULL typeName static VMIntConstantEntry localHotSpotVMIntConstants[]; // Table of long constants required by the serviceability agent. // The last entry is identified over in the serviceability agent by // the fact that it has a NULL typeName static VMLongConstantEntry localHotSpotVMLongConstants[]; // This is used to run any checking code necessary for validation of // the data structure (debug build only) static void init(); private: // Look up a type in localHotSpotVMTypes using strcmp() (debug build only). // Returns 1 if found, 0 if not. // debug_only(static int findType(const char* typeName);) static int findType(const char* typeName); }; #endif // SHARE_VM_RUNTIME_VMSTRUCTS_HPP