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SCImplementedAPI.cpp
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/*******************************************************************************
* Copyright (c) 2001, 2021 IBM Corp. and others
*
* This program and the accompanying materials are made available under
* the terms of the Eclipse Public License 2.0 which accompanies this
* distribution and is available at https://www.eclipse.org/legal/epl-2.0/
* or the Apache License, Version 2.0 which accompanies this distribution and
* is available at https://www.apache.org/licenses/LICENSE-2.0.
*
* This Source Code may also be made available under the following
* Secondary Licenses when the conditions for such availability set
* forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
* General Public License, version 2 with the GNU Classpath
* Exception [1] and GNU General Public License, version 2 with the
* OpenJDK Assembly Exception [2].
*
* [1] https://www.gnu.org/software/classpath/license.html
* [2] http://openjdk.java.net/legal/assembly-exception.html
*
* SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
*******************************************************************************/
#ifdef __cplusplus
extern "C"
{
#endif
#include "shrinit.h"
#include "verbose_api.h"
#include "j2sever.h"
#include "ut_j9shr.h"
#ifdef __cplusplus
}
#endif
#include "hookhelpers.hpp"
#include "CacheMap.hpp"
#include "CompositeCacheImpl.hpp"
#include "SCImplementedAPI.hpp"
#define TSTATE_STOPPED 0
#define TSTATE_STARTED 1
#define TSTATE_ENTER_WRITEMUTEX 2
#define TSTATE_ENTER_SEGMENTMUTEX 3
#define TSTATE_ENTER_READWRITEMUTEX 4
#define TSTATE_ENTER_READWRITEMUTEX_WITHOUT_WRITEMUTEX 5
typedef char* BlockPtr;
/**
* Start a transaction to allow string intern tree manipulation
*
* @param [in/out] tobj transaction object memory
* @param [in] tobj thread using this transaction
*
* @return 0 if ok, otherwise something is wrong
*
* THREADING: On success this function will acquire 3 locks:
* - shared classes: string table mutex (if not readonly)
*/
IDATA
j9shr_stringTransaction_start(void * tobj, J9VMThread* currentThread)
{
IDATA retval = 0;
J9SharedStringTransaction * obj = (J9SharedStringTransaction *) tobj;
J9SharedClassConfig * sconfig = currentThread->javaVM->sharedClassConfig;
U_64 localRuntimeFlags = 0;
BOOLEAN readOnly = false;
SH_CacheMap* cachemap = (SH_CacheMap*) (sconfig->sharedClassCache);
UDATA doRebuildLocalData = 0;
UDATA doRebuildCacheData = 0;
J9SharedInvariantInternTable* table = currentThread->javaVM->sharedInvariantInternTable;
const char * fname = "j9shr_stringTransaction_start";
Trc_SHR_API_j9shr_stringTransaction_start_Entry(currentThread);
if (NULL == tobj) {
Trc_SHR_API_j9shr_stringTransaction_start_tobj_Event(currentThread);
retval = -1;
goto done;
}
/*NOTE:
* We set the state as we take the locks so that during the call to stop we can clean up correctly.
* There may be a better way to do this.
*/
obj->transactionState = TSTATE_STARTED;
obj->ownerThread = currentThread;
obj->isOK = 0;
cachemap->updateRuntimeFullFlags(currentThread);
localRuntimeFlags = sconfig->runtimeFlags;
readOnly = J9_ARE_ANY_BITS_SET(localRuntimeFlags, J9SHR_RUNTIMEFLAG_BLOCK_SPACE_FULL | J9SHR_RUNTIMEFLAG_AVAILABLE_SPACE_FULL);
if (!(localRuntimeFlags & J9SHR_RUNTIMEFLAG_CACHE_INITIALIZATION_COMPLETE)) {
Trc_SHR_API_j9shr_stringTransaction_start_NotInit_Event(currentThread, localRuntimeFlags);
retval = -1;
goto done;
}
Trc_SHR_API_Assert_mustHaveVMAccess(currentThread);
/*NOTE:
* Skip enterStringTableMutex() if invariantInternSharedPool is NULL
*/
if (table != NULL) {
if (0 != (localRuntimeFlags & J9SHR_RUNTIMEFLAG_ENABLE_MPROTECT_ALL)) {
if (omrthread_monitor_enter(currentThread->javaVM->classMemorySegments->segmentMutex) != 0) {
Trc_SHR_API_j9shr_stringTransaction_start_SegMutex_Event(currentThread);
retval = -1;
goto done;
}
obj->transactionState = TSTATE_ENTER_SEGMENTMUTEX;
/*Take a write mutex on the shared cache. This will be released in when the transaction is stopped.*/
if (cachemap->startClassTransaction(currentThread, false, fname) != 0) {
Trc_SHR_API_j9shr_stringTransaction_start_WriteLock_Event(currentThread);
retval = -1;
goto done;
}
obj->transactionState = TSTATE_ENTER_WRITEMUTEX;
}
/*NOTE:
* - If cache is opened with -Xshareclasses:readonly, then enterStringTableMutex() will fail to acquire the lock
*/
if (cachemap->enterStringTableMutex(currentThread, readOnly, &doRebuildLocalData, &doRebuildCacheData) != 0) {
Trc_SHR_API_j9shr_stringTransaction_start_STLock_Event(currentThread, localRuntimeFlags, cachemap->getStringTableBytes(),
readOnly, doRebuildLocalData, doRebuildCacheData);
retval = -1;
goto done;
}
if (doRebuildCacheData) {
j9shr_resetSharedStringTable(currentThread->javaVM);
}
/* State can be TSTATE_ENTER_WRITEMUTEX here, only if mprotect=all option is specified */
if (TSTATE_ENTER_WRITEMUTEX == obj->transactionState) {
obj->transactionState = TSTATE_ENTER_READWRITEMUTEX;
} else {
obj->transactionState = TSTATE_ENTER_READWRITEMUTEX_WITHOUT_WRITEMUTEX;
}
} else {
Trc_SHR_API_j9shr_stringTransaction_start_NoStringTable(currentThread);
retval = -1;
goto done;
}
done:
if ((table != NULL) && ((table->flags & J9AVLTREE_DO_VERIFY_TREE_STRUCT_AND_ACCESS) != 0)) {
/* If the JVM is started with -Xshareclasses:verifyInternTree the local and shared tree should be verified
* before any "string intern" work occurs.
*
* The shared tree can only be verified if the string table lock was entered.
*/
UDATA action = STRINGINTERNTABLES_ACTION_VERIFY_LOCAL_TABLE_ONLY;
if (obj->transactionState == TSTATE_ENTER_READWRITEMUTEX) {
action = STRINGINTERNTABLES_ACTION_VERIFY_BOTH_TABLES;
}
table->performNodeAction(table, NULL, action, NULL);
}
if (retval == -1) {
obj->isOK = -1;
}
Trc_SHR_API_j9shr_stringTransaction_start_Exit(currentThread);
return retval;
}
/**
* End a transaction to allow string intern tree manipulation
*
* @param [in/out] tobj transaction object memory
*
* @return 0 if ok, otherwise something is wrong
*
* THREADING: On success this function will acquire 3 locks:
* - shared classes: string table mutex (if not readonly)
*/
IDATA
j9shr_stringTransaction_stop(void * tobj)
{
IDATA retval = 0;
J9SharedStringTransaction * obj = (J9SharedStringTransaction *) tobj;
J9VMThread* currentThread = obj->ownerThread;
J9SharedInvariantInternTable* table = currentThread->javaVM->sharedInvariantInternTable;
J9SharedClassConfig * sconfig = currentThread->javaVM->sharedClassConfig;
SH_CacheMap* cachemap = (SH_CacheMap*) (sconfig->sharedClassCache);
const char * fname = "j9shr_stringTransaction_stop";
Trc_SHR_API_j9shr_stringTransaction_stop_Entry(currentThread, obj->transactionState);
if ((obj->transactionState != TSTATE_ENTER_READWRITEMUTEX_WITHOUT_WRITEMUTEX) &&
(obj->transactionState != TSTATE_ENTER_READWRITEMUTEX) &&
(obj->transactionState != TSTATE_ENTER_WRITEMUTEX) &&
(obj->transactionState != TSTATE_ENTER_SEGMENTMUTEX) &&
(obj->transactionState != TSTATE_STARTED)) {
Trc_SHR_API_j9shr_stringTransaction_stop_NotStarted_Event(currentThread);
retval = SCSTRING_TRANSACTION_STOP_ERROR;
goto done;
}
if ((table != NULL) && ((table->flags & J9AVLTREE_DO_VERIFY_TREE_STRUCT_AND_ACCESS) != 0)) {
/* If the JVM is started with -Xshareclasses:verifyInternTree the local and shared tree should be verified
* after any "string intern" work occurs.
*
* The shared tree can only be verified if the string table lock was entered.
*/
UDATA action = STRINGINTERNTABLES_ACTION_VERIFY_LOCAL_TABLE_ONLY;
if (obj->transactionState == TSTATE_ENTER_READWRITEMUTEX_WITHOUT_WRITEMUTEX) {
action = STRINGINTERNTABLES_ACTION_VERIFY_BOTH_TABLES;
}
table->performNodeAction(table, NULL, action, NULL);
}
/*NOTE:
* If cache is readonly or string table is 0 size ... we will fail to acquire the lock
*/
if ((TSTATE_ENTER_READWRITEMUTEX_WITHOUT_WRITEMUTEX == obj->transactionState) ||
(TSTATE_ENTER_READWRITEMUTEX == obj->transactionState)) {
/* No new elements are allocated in the string pool during a string transaction.
* Elements can be promoted, but promoted elements use an existing shared node.
*/
if (((SH_CacheMap*)currentThread->javaVM->sharedClassConfig->sharedClassCache)->exitStringTableMutex(currentThread, J9SHR_STRING_POOL_OK) != 0) {
Trc_SHR_API_j9shr_stringTransaction_stop_ExitSTMutex_Event(currentThread);
retval = SCSTRING_TRANSACTION_STOP_ERROR;
}
}
if ((TSTATE_ENTER_READWRITEMUTEX == obj->transactionState) ||
(TSTATE_ENTER_WRITEMUTEX == obj->transactionState)) {
if (cachemap->exitClassTransaction(currentThread, fname) != 0) {
Trc_SHR_API_j9shr_stringTransaction_stop_ExitWriteMutex_Event(currentThread);
retval = SCSTRING_TRANSACTION_STOP_ERROR;
}
}
if ((TSTATE_ENTER_READWRITEMUTEX == obj->transactionState) ||
(TSTATE_ENTER_WRITEMUTEX == obj->transactionState) ||
(TSTATE_ENTER_SEGMENTMUTEX == obj->transactionState)) {
if (omrthread_monitor_exit(currentThread->javaVM->classMemorySegments->segmentMutex) != 0) {
Trc_SHR_API_j9shr_stringTransaction_stop_ExitSegMutex_Event(currentThread);
retval = SCSTRING_TRANSACTION_STOP_ERROR;
}
}
done:
if (retval == SCSTRING_TRANSACTION_STOP_ERROR) {
obj->isOK = -1;
}
Trc_SHR_API_j9shr_stringTransaction_stop_Exit(currentThread);
return retval;
}
/**
* Query the current state, and check if it is good.
*
* @param [in] tobj the current transaction
*
* @return TRUE if ok, otherwise something is wrong
*
*/
BOOLEAN
j9shr_stringTransaction_IsOK(void * tobj)
{
J9SharedStringTransaction * obj = (J9SharedStringTransaction *) tobj;
if (obj->isOK != 0) {
return FALSE;
} else {
return TRUE;
}
}
/**
* Query the current state, and check if it is good.
*
* @param [in] tobj the current transaction
*
* @return TRUE if ok, otherwise something is wrong
*
*/
BOOLEAN
j9shr_classStoreTransaction_isOK(void * tobj)
{
J9SharedClassTransaction * obj = (J9SharedClassTransaction *) tobj;
if (obj->isOK != 0) {
return FALSE;
} else {
return TRUE;
}
}
/**
* Query if the string table lock is owned by the current transaction.
*
* @param [in] tobj the current transaction
*
* @return TRUE if the transaction owns the string table mutex,
* otherwise the transaction does not own the lock
*
*/
BOOLEAN
j9shr_classStoreTransaction_hasSharedStringTableLock(void * tobj)
{
J9SharedClassTransaction * obj = (J9SharedClassTransaction *) tobj;
if (obj->transactionState == TSTATE_ENTER_READWRITEMUTEX) {
return TRUE;
}
return FALSE;
}
void
j9shr_classStoreTransaction_updateUnstoredBytes(U_32 romClassSizeFullSize, void * tobj)
{
J9SharedClassTransaction * obj = (J9SharedClassTransaction *) tobj;
J9SharedClassConfig * sconfig = obj->ownerThread->javaVM->sharedClassConfig;
SH_CacheMap* cachemap = (SH_CacheMap*) (sconfig->sharedClassCache);
cachemap->increaseTransactionUnstoredBytes(romClassSizeFullSize, obj);
}
/**
* Start a transaction to store a shared class
*
* @param [in] tobj transaction object memory
* @param [in] currentThread thread using this transaction
* @param [in] classloader classloader being used for this new class
* @param [in] entryIndex classpath index
* @param [in] loadType load type for the new class
* @param [in] classnameLength class name length
* @param [in] classnameData class name data
* @param [in] isModifiedClassfile true if the class to be stored is modified
*
* @return 0 if ok, otherwise something is wrong
*
* THREADING: On success this function will acquire 3 locks:
* - JVM: segment mutex
* - shared classes: string table mutex (if not readonly)
* - shared classes: write mutex (if not readonly, if cache is not full)
*/
IDATA
j9shr_classStoreTransaction_start(void * tobj, J9VMThread* currentThread, J9ClassLoader* classloader, J9ClassPathEntry* classPathEntries, UDATA cpEntryCount, UDATA entryIndex, UDATA loadType, const J9UTF8* partition, U_16 classnameLength, U_8 * classnameData, BOOLEAN isModifiedClassfile, BOOLEAN takeReadWriteLock)
{
const char * fname = "j9shr_classStoreTransaction_start";
IDATA retval = 0;
J9SharedClassTransaction * obj = (J9SharedClassTransaction *) tobj;
J9SharedClassConfig * sconfig = currentThread->javaVM->sharedClassConfig;
U_64 localRuntimeFlags = sconfig->runtimeFlags;
SH_CacheMap* cachemap = (SH_CacheMap*) (sconfig->sharedClassCache);
ClasspathItem * classpath = NULL;
const J9UTF8* modContext = NULL;
J9SharedInvariantInternTable* table = currentThread->javaVM->sharedInvariantInternTable;
J9JavaVM* vm = currentThread->javaVM;
Trc_SHR_API_j9shr_classStoreTransaction_start_Entry((UDATA)currentThread, (UDATA)classloader, (UDATA)classPathEntries, cpEntryCount, entryIndex, loadType, (UDATA)partition, (UDATA)classnameLength, classnameData, (UDATA)isModifiedClassfile, (UDATA)takeReadWriteLock);
if (NULL == tobj) {
Trc_SHR_API_j9shr_classStoreTransaction_start_tobj_Event(currentThread);
retval = -1;
goto done;
}
/*Note:
* - transactionState, oldVMState, & ownerThread must be set as early as possible (b/c they are used in j9shr_classStoreTransaction_stop())
*/
obj->transactionState = TSTATE_STARTED;
obj->ownerThread = currentThread;
/*Set the VM state to indicate we are potentially storing a class*/
if (currentThread->omrVMThread->vmState != J9VMSTATE_SHAREDCLASS_STORE) {
obj->oldVMState = currentThread->omrVMThread->vmState;
currentThread->omrVMThread->vmState = J9VMSTATE_SHAREDCLASS_STORE;
} else {
obj->oldVMState = (UDATA)-1;
}
if ((loadType == J9SHR_LOADTYPE_REDEFINED) || ((loadType == J9SHR_LOADTYPE_RETRANSFORMED) && (localRuntimeFlags & J9SHR_RUNTIMEFLAG_ENABLE_CACHERETRANSFORMED) == 0)) {
Trc_SHR_API_j9shr_classStoreTransaction_start_Loadtype_Event(currentThread, loadType, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
if (localRuntimeFlags & J9SHR_RUNTIMEFLAG_DENY_CACHE_ACCESS) {
Trc_SHR_API_j9shr_classStoreTransaction_start_DenyAccess_Event(currentThread, localRuntimeFlags, classnameLength, classnameData);
retval = -1;
goto done;
}
/* The entryIndex will be -1 for generated classes */
if ((entryIndex > MAX_CLASS_PATH_ENTRIES) && (entryIndex != UDATA_MAX)) {
Trc_SHR_API_j9shr_classStoreTransaction_start_CPIndex_Event(currentThread, entryIndex, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
if (NULL == cachemap->getROMClassManager(currentThread)) {
Trc_SHR_API_j9shr_classStoreTransaction_start_RCMNotStarted_Event(currentThread, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
if (!(localRuntimeFlags & J9SHR_RUNTIMEFLAG_CACHE_INITIALIZATION_COMPLETE)) {
Trc_SHR_API_j9shr_classStoreTransaction_start_NotInit_Event(currentThread, localRuntimeFlags, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
if (partition != NULL) {
Trc_SHR_API_j9shr_classStoreTransaction_start_NonNullPartition_Event(currentThread, J9UTF8_LENGTH(partition),J9UTF8_DATA(partition));
}
obj->classloader = classloader;
obj->entryIndex = (I_16)entryIndex;
obj->loadType = loadType;
obj->classnameLength = classnameLength;
obj->classnameData = classnameData;
obj->isOK = 0;
obj->helperID = 0;
obj->partitionInCache = NULL;
obj->modContextInCache = NULL;
obj->allocatedMem = NULL;
obj->allocatedLineNumberTableSize = 0;
obj->allocatedLocalVariableTableSize = 0;
obj->allocatedLineNumberTable = NULL;
obj->allocatedLocalVariableTable = NULL;
obj->ClasspathWrapper = NULL;
obj->cacheAreaForAllocate = NULL;
obj->newItemInCache = NULL;
obj->firstFound = NULL;
obj->findNextIterator = NULL;
obj->findNextRomClass = NULL;
obj->isModifiedClassfile = ((isModifiedClassfile == TRUE)?1:0);
obj->takeReadWriteLock = ((takeReadWriteLock==TRUE)?1:0);
obj->cacheFullFlags = 0;
/*NOTE:
* Must omrthread_monitor_enter(segmentMutex) before enterWriteMutex(). Otherwise we will deadlock with hookFindSharedClass()
*/
if (omrthread_monitor_enter(vm->classMemorySegments->segmentMutex) != 0) {
Trc_SHR_API_j9shr_classStoreTransaction_start_SegMutex_Event(currentThread, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
obj->transactionState = TSTATE_ENTER_SEGMENTMUTEX;
if (sconfig->classnameFilterPool) {
if (checkForStoreFilter(vm, classloader, (const char*) classnameData, (UDATA)classnameLength, sconfig->classnameFilterPool)) {
Trc_SHR_API_j9shr_classStoreTransaction_start_StoreFilt_Event(currentThread, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
}
if (takeReadWriteLock == TRUE) {
/* When this function is called from the j9shr_jclUpdateROMClassMetaData()
* - takeReadWriteLock == FALSE,
* - and we do not have vm access.
* In this case we skip this check. Calls from the JCL do not require vm access
* because structures like 'class segments' are not updated when only meta-data
* is added to the shared cache.
*/
Trc_SHR_API_Assert_mustHaveVMAccess(currentThread);
}
/*
* Do work to initialize the below:
* obj->ClasspathWrapper
* obj->partitionInCache
* obj->modContextInCache
* obj->helperID
*
* The are all used during ::allocate and ::commit.
*/
modContext = sconfig->modContext;
if ((classloader != NULL)
&& (J9SHR_LOADTYPE_NORMAL == loadType) /* no need to set classpath if loadType is not J9SHR_LOADTYPE_NORMAL */
) {
/* default values for bootstrap: */
IDATA helperID = 0;
U_16 cpType = CP_TYPE_CLASSPATH;
if ((J2SE_VERSION(vm) >= J2SE_V11)
|| ((NULL != classPathEntries) && (-1 != obj->entryIndex))
) {
/* For class loaded from modules that entryIndex is -1. classPathEntries can be NULL. */
void* cpExtraInfo = NULL;
UDATA infoFound = 0;
if (NULL != classPathEntries) {
cpExtraInfo= classPathEntries->extraInfo;
infoFound = translateExtraInfo(cpExtraInfo, &helperID, &cpType, &classpath);
}
/* Bootstrap loader does not provide meaningful extraInfo */
if (!classpath && !infoFound) {
UDATA pathEntryCount = cpEntryCount;
if (J2SE_VERSION(vm) >= J2SE_V11) {
if (classloader == vm->systemClassLoader) {
if (J9_ARE_NO_BITS_SET(localRuntimeFlags, J9SHR_RUNTIMEFLAG_ENABLE_CACHEBOOTCLASSES)) {
/* User specified noBootclasspath - do not continue */
retval = -1;
goto done;
}
/* bootstrap loader searched on path: modulePath:classPathEntries, entryIndex is the index of classPathEntries if loaded from classPathEntries
* or -1 if loaded from modules, so add 1 here */
obj->entryIndex += 1;
pathEntryCount += 1;
classpath = getBootstrapClasspathItem(currentThread, vm->modulesPathEntry, pathEntryCount);
}
} else {
if (J9_ARE_NO_BITS_SET(localRuntimeFlags, J9SHR_RUNTIMEFLAG_ENABLE_CACHEBOOTCLASSES)) {
/* User specified noBootclasspath - do not continue */
retval = -1;
goto done;
}
classpath = getBootstrapClasspathItem(currentThread, classPathEntries, pathEntryCount);
}
}
if (!classpath) {
/* No cached classpath found. Need to create a new one. */
if ((NULL != classPathEntries) || (classloader == vm->systemClassLoader)) {
classpath = createClasspath(currentThread, classPathEntries, cpEntryCount, helperID, cpType, infoFound);
if (NULL == classpath) {
retval = -1;
goto done;
}
}
}
}
}
if (J9_ARE_ALL_BITS_SET(localRuntimeFlags, J9SHR_RUNTIMEFLAG_BLOCK_SPACE_FULL)) {
obj->cacheFullFlags |= J9SHR_RUNTIMEFLAG_BLOCK_SPACE_FULL;
Trc_SHR_API_j9shr_classStoreTransaction_start_cacheFull_Event(currentThread);
} else if (J9_ARE_ALL_BITS_SET(localRuntimeFlags, J9SHR_RUNTIMEFLAG_AVAILABLE_SPACE_FULL)) {
obj->cacheFullFlags |= J9SHR_RUNTIMEFLAG_AVAILABLE_SPACE_FULL;
Trc_SHR_API_j9shr_classStoreTransaction_start_cacheSoftFull_Event(currentThread);
}
if (0 != obj->cacheFullFlags) {
obj->ClasspathWrapper = (void *) classpath;
obj->helperID = ((NULL == classpath) ? -1 : classpath->getHelperID());
/* let retVal to be 0 */
goto done;
}
/*Take a write mutex on the shared cache. This will be released in when the transaction is stopped.*/
if (cachemap->startClassTransaction(currentThread, false, fname) != 0) {
Trc_SHR_API_j9shr_classStoreTransaction_start_WriteLock_Event(currentThread, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
obj->transactionState = TSTATE_ENTER_WRITEMUTEX;
if (NULL != classpath) {
ClasspathWrapper* cpw = NULL;
const J9UTF8* cachedModContext = NULL;
const J9UTF8* cachedPartition = NULL;
bool readOnly = (localRuntimeFlags & (J9SHR_RUNTIMEFLAG_ENABLE_READONLY | J9SHR_RUNTIMEFLAG_DENY_CACHE_UPDATES )) ? true : false;
/* CMVC 182368 : When running in read-only mode, J9SharedClassTransaction.ClasspathWrapper is not used.
* We can keep it as NULL to prevent any spurious calls to commit data in j9shr_classStoreTransaction_stop().
*/
if (true == readOnly) {
/* We've already identified that an element of this classpath is stale. Sharing is therefore disabled for this classpath. */
if (classpath->flags & MARKED_STALE_FLAG) {
Trc_SHR_API_j9shr_classStoreTransaction_start_CPIsStale_Event(currentThread, classpath->flags, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
} else {
if ((cpw = cachemap->updateClasspathInfo(currentThread, classpath, obj->entryIndex, partition, &cachedPartition, modContext, &cachedModContext, true /*we own the write area lock*/)) == NULL) {
/* Likely cache is full or read failure updating hashtables */
Trc_SHR_API_j9shr_classStoreTransaction_start_updateCPInfo_Event(currentThread, obj->entryIndex, (UDATA)classnameLength, classnameData);
retval = -1;
goto done;
}
obj->ClasspathWrapper = (void *) cpw;
obj->partitionInCache = (J9UTF8*)cachedPartition;
obj->modContextInCache = (J9UTF8*)cachedModContext;
obj->helperID = ((NULL == classpath) ? -1 : classpath->getHelperID());
}
}
done:
if ((table != NULL) && ((table->flags & J9AVLTREE_DO_VERIFY_TREE_STRUCT_AND_ACCESS) != 0)) {
/* If the JVM is started with -Xshareclasses:verifyInternTree the local and shared tree should be verified
* before any "string intern" work occurs.
*
* The shared tree can only be verified if the string table lock was entered.
*/
UDATA action = STRINGINTERNTABLES_ACTION_VERIFY_LOCAL_TABLE_ONLY;
if (obj->transactionState == TSTATE_ENTER_WRITEMUTEX || obj->transactionState == TSTATE_ENTER_READWRITEMUTEX) {
action = STRINGINTERNTABLES_ACTION_VERIFY_BOTH_TABLES;
}
table->performNodeAction(table, NULL, action, NULL);
}
if (retval == -1) {
obj->isOK = -1;
}
Trc_SHR_API_j9shr_classStoreTransaction_start_Exit(currentThread);
return retval;
}
/**
* End a transaction to store a shared class, and if required commit a new class (or meta-data) to the shared cache
*
* @param [in] tobj initialized transaction object memory
*
* @return the below values
* SCCLASS_STORE_STOP_ERROR if nothing was stored
* SCCLASS_STORE_STOP_NOTHING_STORED if data was stored
* SCCLASS_STORE_STOP_DATA_STORED something is wrong (an error will always override one of the above)
*
* THREADING: On success this function will releases 3 locks:
* - JVM: segment mutex
* - shared classes: string table mutex (if not readonly)
* - shared classes: write mutex (if not readonly)
*/
IDATA
j9shr_classStoreTransaction_stop(void * tobj)
{
IDATA retval = SCCLASS_STORE_STOP_NOTHING_STORED;
const char *fname = "j9shr_classStoreTransaction_stop";
J9SharedClassTransaction *obj = (J9SharedClassTransaction *)tobj;
J9VMThread *currentThread = obj->ownerThread;
J9JavaVM *vm = currentThread->javaVM;
J9SharedClassConfig *sconfig = vm->sharedClassConfig;
SH_CacheMap *cachemap = (SH_CacheMap *)sconfig->sharedClassCache;
bool releaseWriteMutex;
bool releaseReadWriteMutex;
bool releaseSegmentMutex;
UDATA oldVMState = obj->oldVMState;
ClasspathWrapper *cpw = NULL;
ClasspathItem *classpath = NULL;
IDATA didWeStore = 0;
bool modifiedNoContext = ((obj->isModifiedClassfile == 1) && (NULL == obj->modContextInCache));
J9ROMClass *storedClass = NULL;
J9UTF8 *storedClassName = NULL;
J9SharedInvariantInternTable *table = currentThread->javaVM->sharedInvariantInternTable;
Trc_SHR_API_j9shr_classStoreTransaction_stop_Entry(currentThread, obj->transactionState);
if (0 != obj->cacheFullFlags) {
classpath = (ClasspathItem*) obj->ClasspathWrapper;
} else {
cpw = (ClasspathWrapper*) obj->ClasspathWrapper;
}
/*if started go to done ...*/
if (obj->transactionState == TSTATE_STARTED) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_isOnlyStarted_Event(currentThread);
retval = SCCLASS_STORE_STOP_ERROR;
goto done;
}
if (obj->transactionState != TSTATE_ENTER_SEGMENTMUTEX && obj->transactionState != TSTATE_ENTER_READWRITEMUTEX && obj->transactionState != TSTATE_ENTER_WRITEMUTEX) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_NotStarted_Event(currentThread, obj->transactionState);
retval = SCCLASS_STORE_STOP_ERROR;
goto done;
}
releaseReadWriteMutex = (obj->transactionState == TSTATE_ENTER_READWRITEMUTEX);
releaseWriteMutex = (obj->transactionState == TSTATE_ENTER_WRITEMUTEX || obj->transactionState == TSTATE_ENTER_READWRITEMUTEX);
releaseSegmentMutex = (obj->transactionState == TSTATE_ENTER_SEGMENTMUTEX || obj->transactionState == TSTATE_ENTER_READWRITEMUTEX || obj->transactionState == TSTATE_ENTER_WRITEMUTEX);
if ((table != NULL) && ((table->flags & J9AVLTREE_DO_VERIFY_TREE_STRUCT_AND_ACCESS) != 0)) {
/* If the JVM is started with -Xshareclasses:verifyInternTree the local and shared tree should be verified
* after any "string intern" work occurs.
*
* The shared tree can only be verified if the string table lock was entered.
*/
UDATA action = STRINGINTERNTABLES_ACTION_VERIFY_LOCAL_TABLE_ONLY;
if (releaseReadWriteMutex == true) {
action = STRINGINTERNTABLES_ACTION_VERIFY_BOTH_TABLES;
}
table->performNodeAction(table, NULL, action, NULL);
}
if (releaseWriteMutex == true) {
if ((NULL == obj->newItemInCache) && (NULL == obj->findNextRomClass)) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_NoWork_Event(currentThread, (UDATA) obj->classnameLength, obj->classnameData);
/* The below assert ensures no debug data is ever commited if there is no
* rom class to commit. This assert should never ever trigger.
*/
Trc_SHR_Assert_False( ((NULL != obj->allocatedLineNumberTable) || (NULL != obj->allocatedLocalVariableTable)) );
retval = SCCLASS_STORE_STOP_NOTHING_STORED;
} else {
if (obj->newItemInCache != NULL && cpw != NULL && modifiedNoContext == false) {
storedClass = (J9ROMClass *)obj->allocatedMem;
didWeStore = cachemap->commitROMClass(obj->ownerThread, (ShcItem*)obj->newItemInCache, (SH_CompositeCacheImpl*) obj->cacheAreaForAllocate, (ClasspathWrapper*) cpw, obj->entryIndex, obj->partitionInCache, obj->modContextInCache, (BlockPtr) obj->allocatedMem, true);
} else if (obj->newItemInCache != NULL) {
if (modifiedNoContext == true) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_StoreModifed_Event(currentThread, (UDATA) obj->classnameLength, obj->classnameData, (UDATA)storedClass);
}
storedClass = (J9ROMClass *)obj->allocatedMem;
didWeStore = cachemap->commitOrphanROMClass(obj->ownerThread, (ShcItem*)obj->newItemInCache, (SH_CompositeCacheImpl*) obj->cacheAreaForAllocate, (ClasspathWrapper*) cpw, (BlockPtr) obj->allocatedMem);
} else {
storedClass = (J9ROMClass *)obj->findNextRomClass;
if (modifiedNoContext == true) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_NoNewMetaDataForModBytes_Event(currentThread, (UDATA) obj->classnameLength, obj->classnameData, (UDATA)storedClass);
} else if (NULL == cpw) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_NoNewMetaDataNoCPInfo_Event(currentThread, (UDATA) obj->classnameLength, obj->classnameData, (UDATA)storedClass);
} else {
didWeStore = cachemap->commitMetaDataROMClassIfRequired(obj->ownerThread, (ClasspathWrapper*) cpw, obj->entryIndex, obj->helperID, obj->partitionInCache, obj->modContextInCache, (J9ROMClass *)obj->findNextRomClass);
}
}
storedClassName = J9ROMCLASS_CLASSNAME(storedClass);
/* Verify intermediateClassData in the ROMClass, if available, is within cache boundary */
if (NULL != storedClass) {
U_8 *intermediateClassData = J9ROMCLASS_INTERMEDIATECLASSDATA(storedClass);
if (NULL != intermediateClassData) {
if (j9shr_isAddressInCache(vm, storedClass, storedClass->romSize, TRUE)) {
/* romclass is using SPRs pointing to its intermediateClassData, so they should be in the same cache */
Trc_SHR_Assert_True(j9shr_isAddressInCache(vm, intermediateClassData, storedClass->intermediateClassDataLength, TRUE));
} else {
Trc_SHR_Assert_True(j9shr_isAddressInCache(vm, intermediateClassData, storedClass->intermediateClassDataLength, FALSE));
}
}
}
}
}
/* Display verbose store messages.*/
if (classpath != NULL) {
storeClassVerboseIO(obj->ownerThread, classpath, obj->entryIndex, obj->classnameLength, obj->classnameData, obj->helperID, (didWeStore == 1));
} else {
if (cpw != NULL) {
ClasspathItem * classpath = ((ClasspathItem*) CPWDATA(cpw));
storeClassVerboseIO(obj->ownerThread, classpath, obj->entryIndex, obj->classnameLength, obj->classnameData, obj->helperID, (didWeStore == 1));
}
}
/*Clear the transaction object*/
memset(obj, 0, sizeof(J9SharedClassTransaction));
obj->transactionState = TSTATE_STOPPED;
if (releaseReadWriteMutex) {
if (cachemap->exitStringTableMutex(currentThread, J9SHR_STRING_POOL_OK) != 0) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_ExitSTMutex_Event(currentThread);
retval = SCCLASS_STORE_STOP_ERROR;
}
}
if (releaseWriteMutex) {
if (cachemap->exitClassTransaction(currentThread, fname) != 0) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_ExitWriteMutex_Event(currentThread);
retval = SCCLASS_STORE_STOP_ERROR;
}
}
if (releaseSegmentMutex) {
if (omrthread_monitor_exit(vm->classMemorySegments->segmentMutex) != 0) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_ExitSegMutex_Event(currentThread);
retval = SCCLASS_STORE_STOP_ERROR;
}
}
done:
if (oldVMState != (UDATA) - 1) {
currentThread->omrVMThread->vmState = oldVMState;
}
if (retval == SCCLASS_STORE_STOP_ERROR) {
obj->isOK = -1;
}
if (retval != SCCLASS_STORE_STOP_ERROR && didWeStore == SCCLASS_STORE_STOP_DATA_STORED) {
Trc_SHR_API_j9shr_classStoreTransaction_stop_StoredData_Event(currentThread, (UDATA)J9UTF8_LENGTH(storedClassName), J9UTF8_DATA(storedClassName), storedClass);
retval = SCCLASS_STORE_STOP_DATA_STORED;
}
Trc_SHR_API_j9shr_classStoreTransaction_stop_Exit(currentThread);
return retval;
}
/**
* Iterate thru class with the same ROMClass name that we would like to store.
* - This function is called multiple times to iterate over all the potential matches.
* - This function should be called after starting a transaction.
* - The caller must iterate over all potential matches unless a match is found.
*
* @param [in] tobj initialized transaction object memory
*
* @return NULL if there is no more ROMClasses matching your class name
* in the cache, or NON-NULL if a class is found to exist in the cache.
*
* THREADING: Must own (in atleast read only form):
* - JVM: segment mutex
* - shared classes: write mutex (if not readonly, if cache is not full)
*/
J9ROMClass *
j9shr_classStoreTransaction_nextSharedClassForCompare(void * tobj)
{
J9SharedClassTransaction * obj = (J9SharedClassTransaction *) tobj;
J9VMThread* currentThread = obj->ownerThread;
J9SharedClassConfig * sconfig = currentThread->javaVM->sharedClassConfig;
SH_CacheMap* cachemap = (SH_CacheMap*) (sconfig->sharedClassCache);
Trc_SHR_API_j9shr_nextSharedClassForCompare_Entry(currentThread);
if ((obj->transactionState != TSTATE_ENTER_WRITEMUTEX)
&& (0 == obj->cacheFullFlags)
) {
Trc_SHR_API_j9shr_nextSharedClassForCompare_NotStarted_Event(currentThread, obj->transactionState);
Trc_SHR_API_j9shr_nextSharedClassForCompare_Exit(currentThread);
return NULL;
}
const char *stringBytes = (const char*)obj->classnameData;
U_16 stringLength = obj->classnameLength;
char *end = getLastDollarSignOfLambdaClassName(stringBytes, obj->classnameLength);
if (NULL != end) {
stringLength = (U_16)(end - stringBytes + 1);
}
obj->findNextRomClass = (J9ROMClass *) cachemap->findNextROMClass(currentThread, obj->findNextIterator, obj->firstFound, stringLength, (const char*)obj->classnameData);
Trc_SHR_API_j9shr_nextSharedClassForCompare_Exit(currentThread);
return (J9ROMClass *)(obj->findNextRomClass);
}
IDATA
j9shr_classStoreTransaction_createSharedClass(void * tobj, const J9RomClassRequirements * sizes, J9SharedRomClassPieces * pieces)
{
IDATA retval = 0;
J9SharedClassTransaction * obj = (J9SharedClassTransaction *) tobj;
J9SharedClassConfig * sconfig = obj->ownerThread->javaVM->sharedClassConfig;
U_64 localRuntimeFlags = sconfig->runtimeFlags;
SH_CacheMap* cachemap = (SH_CacheMap*) (sconfig->sharedClassCache);
J9VMThread * currentThread = obj->ownerThread;
bool modifiedNoContext = ((1 == obj->isModifiedClassfile) && (NULL == obj->modContextInCache));
UDATA doRebuildLocalData = 0;
UDATA doRebuildCacheData = 0;
U_16 classnameLength = obj->classnameLength;
const char* classnameData = (const char*)obj->classnameData;
bool allocatedRomClass = false;
Trc_SHR_API_j9shr_createSharedClass_Entry3(currentThread, classnameLength, classnameData, sizes->romClassSizeFullSize, sizes->romClassMinimalSize, sizes->lineNumberTableSize, sizes->localVariableTableSize);
if (-1 == obj->isOK) {
Trc_SHR_API_j9shr_createSharedClass_NotOk_Event(currentThread);
retval = -1;
goto done;
}
if (localRuntimeFlags & J9SHR_RUNTIMEFLAG_ENABLE_READONLY) {
Trc_SHR_API_j9shr_createSharedClass_ReadOnly_Event(currentThread);
retval = -1;
goto done;
}
if (J9_ARE_ALL_BITS_SET(localRuntimeFlags, J9SHR_RUNTIMEFLAG_BLOCK_SPACE_FULL)) {
Trc_SHR_API_j9shr_createSharedClass_Full_Event(currentThread);
retval = -1;
goto done;
}
if (localRuntimeFlags & J9SHR_RUNTIMEFLAG_DENY_CACHE_UPDATES) {
Trc_SHR_API_j9shr_createSharedClass_DenyUpdates_Event(currentThread);
retval = -1;
goto done;
}
if (J9_ARE_ANY_BITS_SET(localRuntimeFlags, J9SHR_RUNTIMEFLAG_AVAILABLE_SPACE_FULL)) {
/* Put this block after the checks for J9SHR_RUNTIMEFLAG_BLOCK_SPACE_FULL and J9SHR_RUNTIMEFLAG_DENY_CACHE_UPDATES, as there is
* no point increasing the unstored bytes if these flags are set
*/
Trc_SHR_API_j9shr_createSharedClass_softFull_Event(currentThread);
cachemap->increaseTransactionUnstoredBytes(sizes->romClassSizeFullSize, obj);
retval = -1;
goto done;
}
if (obj->transactionState != TSTATE_ENTER_WRITEMUTEX) {
Trc_SHR_API_j9shr_createSharedClass_NotStarted_Event(currentThread);
retval = -1;
goto done;
}
if ((0 == sizes->romClassSizeFullSize) || (0 == sizes->romClassMinimalSize)) {
/*The two ROM Class sizes must be non zero*/
Trc_SHR_API_j9shr_createSharedClass_ZeroRomClassSize_Event(currentThread, sizes->romClassSizeFullSize, sizes->romClassMinimalSize);
Trc_SHR_Assert_True(0 != sizes->romClassSizeFullSize);
Trc_SHR_Assert_True(0 != sizes->romClassMinimalSize);
retval = -1;
goto done;
}
/*ROM Class size must be doubled aligned*/
if (0 != (sizes->romClassSizeFullSize & (sizeof(U_64) - 1))) {
Trc_SHR_API_j9shr_createSharedClass_DblAlign_Event(currentThread);
Trc_SHR_Assert_ShouldNeverHappen();
retval = -1;
goto done;
}
/*ROM Class size must be doubled aligned*/
if (0 != (sizes->romClassMinimalSize & (sizeof(U_64) - 1))) {
Trc_SHR_API_j9shr_createSharedClass_DblAlign_Event(currentThread);
Trc_SHR_Assert_ShouldNeverHappen();
retval = -1;
goto done;
}
/*We expect that j9shr_createSharedClass is never called more than once during a transaction*/
if (obj->newItemInCache != NULL) {
Trc_SHR_API_j9shr_createSharedClass_CalledTwice1_Event(currentThread);
retval = -1;
goto done;
}
if (obj->cacheAreaForAllocate != NULL) {
Trc_SHR_API_j9shr_createSharedClass_CalledTwice2_Event(currentThread);
retval = -1;
goto done;
}
Trc_SHR_Assert_True(NULL == obj->allocatedMem);
Trc_SHR_Assert_True(NULL == obj->allocatedLineNumberTable);
Trc_SHR_Assert_True(NULL == obj->allocatedLocalVariableTable);
memset(pieces, 0, sizeof(J9SharedRomClassPieces));
allocatedRomClass = cachemap->allocateROMClass(currentThread,
sizes,
pieces,
obj->classnameLength,
(const char*)(obj->classnameData),
(ClasspathWrapper*)obj->ClasspathWrapper,
obj->partitionInCache,
obj->modContextInCache,
obj->helperID,
modifiedNoContext,
obj->newItemInCache,
obj->cacheAreaForAllocate);
if (false == allocatedRomClass) {
/*Nothing could be allocated*/
Trc_SHR_API_j9shr_createSharedClass_FailedToAllocRomclass_Event(currentThread);
retval = -1;
goto done;
}
Trc_SHR_API_j9shr_createSharedClass_AllocRomclass_Event(currentThread, pieces->romClass);
obj->allocatedLineNumberTableSize = sizes->lineNumberTableSize;
obj->allocatedLocalVariableTableSize = sizes->localVariableTableSize;
obj->allocatedLineNumberTable = pieces->lineNumberTable;
obj->allocatedLocalVariableTable = pieces->localVariableTable;
obj->allocatedMem = pieces->romClass;
/*NOTE:
* Skip enterStringTableMutex() if:
* - the cache is readonly
* - the call to this function is from the JCL natives (obj->takeReadWriteLock == TRUE)
* - invariantInternSharedPool is NULL
*/
if (((localRuntimeFlags & J9SHR_RUNTIMEFLAG_ENABLE_READONLY) == 0)
&& (obj->takeReadWriteLock == 1)
&& (currentThread->javaVM->sharedInvariantInternTable != NULL)) {
/*NOTE:
* If cache is opened with -Xshareclasses:readonly then enterStringTableMutex() will fail to acquire the lock
*/
if (cachemap->enterStringTableMutex(currentThread, FALSE, &doRebuildLocalData, &doRebuildCacheData) != 0) {
Trc_SHR_API_j9shr_createSharedClass_STLock_Event(currentThread, localRuntimeFlags, cachemap->getStringTableBytes(),
FALSE, doRebuildLocalData, doRebuildCacheData, (UDATA)obj->classnameLength, (const char*)obj->classnameData);
} else {
if (doRebuildCacheData) {
j9shr_resetSharedStringTable(currentThread->javaVM);
}
obj->transactionState = TSTATE_ENTER_READWRITEMUTEX;
}
}
done:
Trc_SHR_API_j9shr_createSharedClass_Exit(currentThread, retval);
return retval;
}
/**
* Update the size of a newly allocated ROMClass to something smaller.
* - The call should have allocated a class.
*
* @param [in] tobj initialized transaction object memory
*
* @return NON-NULL if class is successfully allocated from the shared cache.
*
* THREADING: Must own:
* - JVM: segment mutex
* - shared classes: string table mutex
* - shared classes: write mutex
*/