Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 1997, 2009, 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.

  *

  */

 // The VM class loader.

 #include <sys/stat.h>

 // Meta-index (optional, to be able to skip opening boot classpath jar files)

 class MetaIndex: public CHeapObj {

  private:

   char** _meta_package_names;

   int    _num_meta_package_names;

  public:

   MetaIndex(char** meta_package_names, int num_meta_package_names);

   ~MetaIndex();

   bool may_contain(const char* class_name);

 };

 // Class path entry (directory or zip file)

 class ClassPathEntry: public CHeapObj {

  private:

   ClassPathEntry* _next;

  public:

   // Next entry in class path

   ClassPathEntry* next()              { return _next; }

   void set_next(ClassPathEntry* next) {

     // may have unlocked readers, so write atomically.

     OrderAccess::release_store_ptr(&_next, next);

   }

   virtual bool is_jar_file() = 0;

   virtual const char* name() = 0;

   virtual bool is_lazy();

   // Constructor

   ClassPathEntry();

   // Attempt to locate file_name through this class path entry.

   // Returns a class file parsing stream if successfull.

   virtual ClassFileStream* open_stream(const char* name) = 0;

   // Debugging

   NOT_PRODUCT(virtual void compile_the_world(Handle loader, TRAPS) = 0;)

   NOT_PRODUCT(virtual bool is_rt_jar() = 0;)

 };

 class ClassPathDirEntry: public ClassPathEntry {

  private:

   char* _dir;           // Name of directory

  public:

   bool is_jar_file()  { return false;  }

   const char* name()  { return _dir; }

   ClassPathDirEntry(char* dir);

   ClassFileStream* open_stream(const char* name);

   // Debugging

   NOT_PRODUCT(void compile_the_world(Handle loader, TRAPS);)

   NOT_PRODUCT(bool is_rt_jar();)

 };

 // Type definitions for zip file and zip file entry

 typedef void* jzfile;

 typedef struct {

   char *name;                   /* entry name */

   jlong time;                   /* modification time */

   jlong size;                   /* size of uncompressed data */

   jlong csize;                  /* size of compressed data (zero if uncompressed) */

   jint crc;                     /* crc of uncompressed data */

   char *comment;                /* optional zip file comment */

   jbyte *extra;                 /* optional extra data */

   jlong pos;                    /* position of LOC header (if negative) or data */

 } jzentry;

 class ClassPathZipEntry: public ClassPathEntry {

  private:

   jzfile* _zip;        // The zip archive

   char*   _zip_name;   // Name of zip archive

  public:

   bool is_jar_file()  { return true;  }

   const char* name()  { return _zip_name; }

   ClassPathZipEntry(jzfile* zip, const char* zip_name);

   ~ClassPathZipEntry();

   ClassFileStream* open_stream(const char* name);

   void contents_do(void f(const char* name, void* context), void* context);

   // Debugging

   NOT_PRODUCT(void compile_the_world(Handle loader, TRAPS);)

   NOT_PRODUCT(void compile_the_world12(Handle loader, TRAPS);) // JDK 1.2 version

   NOT_PRODUCT(void compile_the_world13(Handle loader, TRAPS);) // JDK 1.3 version

   NOT_PRODUCT(bool is_rt_jar();)

   NOT_PRODUCT(bool is_rt_jar12();)

   NOT_PRODUCT(bool is_rt_jar13();)

 };

 // For lazier loading of boot class path entries

 class LazyClassPathEntry: public ClassPathEntry {

  private:

   char* _path; // dir or file

   struct stat _st;

   MetaIndex* _meta_index;

   volatile ClassPathEntry* _resolved_entry;

   ClassPathEntry* resolve_entry();

  public:

   bool is_jar_file();

   const char* name()  { return _path; }

   LazyClassPathEntry(char* path, struct stat st);

   ClassFileStream* open_stream(const char* name);

   void set_meta_index(MetaIndex* meta_index) { _meta_index = meta_index; }

   virtual bool is_lazy();

   // Debugging

   NOT_PRODUCT(void compile_the_world(Handle loader, TRAPS);)

   NOT_PRODUCT(bool is_rt_jar();)

 };

 class PackageHashtable;

 class PackageInfo;

 class HashtableBucket;

 class ClassLoader: AllStatic {

  public:

   enum SomeConstants {

     package_hash_table_size = 31  // Number of buckets

   };

  private:

   friend class LazyClassPathEntry;

   // Performance counters

   static PerfCounter* _perf_accumulated_time;

   static PerfCounter* _perf_classes_inited;

   static PerfCounter* _perf_class_init_time;

   static PerfCounter* _perf_class_init_selftime;

   static PerfCounter* _perf_classes_verified;

   static PerfCounter* _perf_class_verify_time;

   static PerfCounter* _perf_class_verify_selftime;

   static PerfCounter* _perf_classes_linked;

   static PerfCounter* _perf_class_link_time;

   static PerfCounter* _perf_class_link_selftime;

   static PerfCounter* _perf_class_parse_time;

   static PerfCounter* _perf_class_parse_selftime;

   static PerfCounter* _perf_sys_class_lookup_time;

   static PerfCounter* _perf_shared_classload_time;

   static PerfCounter* _perf_sys_classload_time;

   static PerfCounter* _perf_app_classload_time;

   static PerfCounter* _perf_app_classload_selftime;

   static PerfCounter* _perf_app_classload_count;

   static PerfCounter* _perf_define_appclasses;

   static PerfCounter* _perf_define_appclass_time;

   static PerfCounter* _perf_define_appclass_selftime;

   static PerfCounter* _perf_app_classfile_bytes_read;

   static PerfCounter* _perf_sys_classfile_bytes_read;

   static PerfCounter* _sync_systemLoaderLockContentionRate;

   static PerfCounter* _sync_nonSystemLoaderLockContentionRate;

   static PerfCounter* _sync_JVMFindLoadedClassLockFreeCounter;

   static PerfCounter* _sync_JVMDefineClassLockFreeCounter;

   static PerfCounter* _sync_JNIDefineClassLockFreeCounter;

   static PerfCounter* _unsafe_defineClassCallCounter;

   static PerfCounter* _isUnsyncloadClass;

   static PerfCounter* _load_instance_class_failCounter;

   // First entry in linked list of ClassPathEntry instances

   static ClassPathEntry* _first_entry;

   // Last entry in linked list of ClassPathEntry instances

   static ClassPathEntry* _last_entry;

   // Hash table used to keep track of loaded packages

   static PackageHashtable* _package_hash_table;

   static const char* _shared_archive;

   // Hash function

   static unsigned int hash(const char *s, int n);

   // Returns the package file name corresponding to the specified package

   // or class name, or null if not found.

   static PackageInfo* lookup_package(const char *pkgname);

   // Adds a new package entry for the specified class or package name and

   // corresponding directory or jar file name.

   static bool add_package(const char *pkgname, int classpath_index, TRAPS);

   // Initialization

   static void setup_meta_index();

   static void setup_bootstrap_search_path();

   static void load_zip_library();

   static void create_class_path_entry(char *path, struct stat st, ClassPathEntry **new_entry, bool lazy);

   // Canonicalizes path names, so strcmp will work properly. This is mainly

   // to avoid confusing the zip library

   static bool get_canonical_path(char* orig, char* out, int len);

  public:

   // Used by the kernel jvm.

   static void update_class_path_entry_list(const char *path,

                                            bool check_for_duplicates);

   static void print_bootclasspath();

   // Timing

   static PerfCounter* perf_accumulated_time()         { return _perf_accumulated_time; }

   static PerfCounter* perf_classes_inited()           { return _perf_classes_inited; }

   static PerfCounter* perf_class_init_time()          { return _perf_class_init_time; }

   static PerfCounter* perf_class_init_selftime()      { return _perf_class_init_selftime; }

   static PerfCounter* perf_classes_verified()         { return _perf_classes_verified; }

   static PerfCounter* perf_class_verify_time()        { return _perf_class_verify_time; }

   static PerfCounter* perf_class_verify_selftime()    { return _perf_class_verify_selftime; }

   static PerfCounter* perf_classes_linked()           { return _perf_classes_linked; }

   static PerfCounter* perf_class_link_time()          { return _perf_class_link_time; }

   static PerfCounter* perf_class_link_selftime()      { return _perf_class_link_selftime; }

   static PerfCounter* perf_class_parse_time()         { return _perf_class_parse_time; }

   static PerfCounter* perf_class_parse_selftime()     { return _perf_class_parse_selftime; }

   static PerfCounter* perf_sys_class_lookup_time()    { return _perf_sys_class_lookup_time; }

   static PerfCounter* perf_shared_classload_time()    { return _perf_shared_classload_time; }

   static PerfCounter* perf_sys_classload_time()       { return _perf_sys_classload_time; }

   static PerfCounter* perf_app_classload_time()       { return _perf_app_classload_time; }

   static PerfCounter* perf_app_classload_selftime()   { return _perf_app_classload_selftime; }

   static PerfCounter* perf_app_classload_count()      { return _perf_app_classload_count; }

   static PerfCounter* perf_define_appclasses()        { return _perf_define_appclasses; }

   static PerfCounter* perf_define_appclass_time()     { return _perf_define_appclass_time; }

   static PerfCounter* perf_define_appclass_selftime() { return _perf_define_appclass_selftime; }

   static PerfCounter* perf_app_classfile_bytes_read() { return _perf_app_classfile_bytes_read; }

   static PerfCounter* perf_sys_classfile_bytes_read() { return _perf_sys_classfile_bytes_read; }

   // Record how often system loader lock object is contended

   static PerfCounter* sync_systemLoaderLockContentionRate() {

     return _sync_systemLoaderLockContentionRate;

   }

   // Record how often non system loader lock object is contended

   static PerfCounter* sync_nonSystemLoaderLockContentionRate() {

     return _sync_nonSystemLoaderLockContentionRate;

   }

   // Record how many calls to JVM_FindLoadedClass w/o holding a lock

   static PerfCounter* sync_JVMFindLoadedClassLockFreeCounter() {

     return _sync_JVMFindLoadedClassLockFreeCounter;

   }

   // Record how many calls to JVM_DefineClass w/o holding a lock

   static PerfCounter* sync_JVMDefineClassLockFreeCounter() {

     return _sync_JVMDefineClassLockFreeCounter;

   }

   // Record how many calls to jni_DefineClass w/o holding a lock

   static PerfCounter* sync_JNIDefineClassLockFreeCounter() {

     return _sync_JNIDefineClassLockFreeCounter;

   }

   // Record how many calls to Unsafe_DefineClass

   static PerfCounter* unsafe_defineClassCallCounter() {

     return _unsafe_defineClassCallCounter;

   }

   // Record how many times SystemDictionary::load_instance_class call

   // fails with linkageError when Unsyncloadclass flag is set.

   static PerfCounter* load_instance_class_failCounter() {

     return _load_instance_class_failCounter;

   }

   // Load individual .class file

   static instanceKlassHandle load_classfile(symbolHandle h_name, TRAPS);

   // If the specified package has been loaded by the system, then returns

   // the name of the directory or ZIP file that the package was loaded from.

   // Returns null if the package was not loaded.

   // Note: The specified name can either be the name of a class or package.

   // If a package name is specified, then it must be "/"-separator and also

   // end with a trailing "/".

   static oop get_system_package(const char* name, TRAPS);

   // Returns an array of Java strings representing all of the currently

   // loaded system packages.

   // Note: The package names returned are "/"-separated and end with a

   // trailing "/".

   static objArrayOop get_system_packages(TRAPS);

   // Initialization

   static void initialize();

   static void create_package_info_table();

   static void create_package_info_table(HashtableBucket *t, int length,

                                         int number_of_entries);

   static int compute_Object_vtable();

   static ClassPathEntry* classpath_entry(int n) {

     ClassPathEntry* e = ClassLoader::_first_entry;

     while (--n >= 0) {

       assert(e != NULL, "Not that many classpath entries.");

       e = e->next();

     }

     return e;

   }

   // Sharing dump and restore

   static void copy_package_info_buckets(char** top, char* end);

   static void copy_package_info_table(char** top, char* end);

   // VM monitoring and management support

   static jlong classloader_time_ms();

   static jlong class_method_total_size();

   static jlong class_init_count();

   static jlong class_init_time_ms();

   static jlong class_verify_time_ms();

   static jlong class_link_count();

   static jlong class_link_time_ms();

   // indicates if class path already contains a entry (exact match by name)

   static bool contains_entry(ClassPathEntry* entry);

   // adds a class path list

   static void add_to_list(ClassPathEntry* new_entry);

   // creates a class path zip entry (returns NULL if JAR file cannot be opened)

   static ClassPathZipEntry* create_class_path_zip_entry(const char *apath);

   // Debugging

   static void verify()              PRODUCT_RETURN;

   // Force compilation of all methods in all classes in bootstrap class path (stress test)

 #ifndef PRODUCT

  private:

   static int _compile_the_world_counter;

  public:

   static void compile_the_world();

   static void compile_the_world_in(char* name, Handle loader, TRAPS);

   static int  compile_the_world_counter() { return _compile_the_world_counter; }

 #endif //PRODUCT

 };

 // PerfClassTraceTime is used to measure time for class loading related events.

 // This class tracks cumulative time and exclusive time for specific event types.

 // During the execution of one event, other event types (e.g. class loading and

 // resolution) as well as recursive calls of the same event type could happen.

 // Only one elapsed timer (cumulative) and one thread-local self timer (exclusive)

 // (i.e. only one event type) are active at a time even multiple PerfClassTraceTime

 // instances have been created as multiple events are happening.

 class PerfClassTraceTime {

   public:

     enum {

        CLASS_LOAD   = 0,

        PARSE_CLASS  = 1,

        CLASS_LINK   = 2,

        CLASS_VERIFY = 3,

        CLASS_CLINIT = 4,

        DEFINE_CLASS = 5,

        EVENT_TYPE_COUNT = 6

     };

   protected:

     // _t tracks time from initialization to destruction of this timer instance

     // including time for all other event types, and recursive calls of this type.

     // When a timer is called recursively, the elapsedTimer _t would not be used.

     elapsedTimer     _t;

     PerfLongCounter* _timep;

     PerfLongCounter* _selftimep;

     PerfLongCounter* _eventp;

     // pointer to thread-local recursion counter and timer array

     // The thread_local timers track cumulative time for specific event types

     // exclusive of time for other event types, but including recursive calls

     // of the same type.

     int*             _recursion_counters;

     elapsedTimer*    _timers;

     int              _event_type;

     int              _prev_active_event;

   public:

     inline PerfClassTraceTime(PerfLongCounter* timep,     /* counter incremented with inclusive time */

                               PerfLongCounter* selftimep, /* counter incremented with exclusive time */

                               PerfLongCounter* eventp,    /* event counter */

                               int* recursion_counters,    /* thread-local recursion counter array */

                               elapsedTimer* timers,       /* thread-local timer array */

                               int type                    /* event type */ ) :

         _timep(timep), _selftimep(selftimep), _eventp(eventp), _recursion_counters(recursion_counters), _timers(timers), _event_type(type) {

       initialize();

     }

     inline PerfClassTraceTime(PerfLongCounter* timep,     /* counter incremented with inclusive time */

                               elapsedTimer* timers,       /* thread-local timer array */

                               int type                    /* event type */ ) :

         _timep(timep), _selftimep(NULL), _eventp(NULL), _recursion_counters(NULL), _timers(timers), _event_type(type) {

       initialize();

     }

     void initialize() {

       if (!UsePerfData) return;

       if (_eventp != NULL) {

         // increment the event counter

         _eventp->inc();

       }

       // stop the current active thread-local timer to measure inclusive time

       _prev_active_event = -1;

       for (int i=0; i < EVENT_TYPE_COUNT; i++) {

          if (_timers[i].is_active()) {

            assert(_prev_active_event == -1, "should have only one active timer");

            _prev_active_event = i;

            _timers[i].stop();

          }

       }

       if (_recursion_counters == NULL || (_recursion_counters[_event_type])++ == 0) {

         // start the inclusive timer if not recursively called

         _t.start();

       }

       // start thread-local timer of the given event type

       if (!_timers[_event_type].is_active()) {

         _timers[_event_type].start();

       }

     }

     inline void suspend() { _t.stop(); _timers[_event_type].stop(); }

     inline void resume()  { _t.start(); _timers[_event_type].start(); }

     ~PerfClassTraceTime() {

       if (!UsePerfData) return;

       // stop the thread-local timer as the event completes

       // and resume the thread-local timer of the event next on the stack

       _timers[_event_type].stop();

       jlong selftime = _timers[_event_type].ticks();

       if (_prev_active_event >= 0) {

         _timers[_prev_active_event].start();

       }

       if (_recursion_counters != NULL && --(_recursion_counters[_event_type]) > 0) return;

       // increment the counters only on the leaf call

       _t.stop();

       _timep->inc(_t.ticks());

       if (_selftimep != NULL) {

         _selftimep->inc(selftime);

       }

       // add all class loading related event selftime to the accumulated time counter

       ClassLoader::perf_accumulated_time()->inc(selftime);

       // reset the timer

       _timers[_event_type].reset();

     }

 };