6578152: fill_region_with_object has usability and safety issues
Reviewed-by: apetrusenko, ysr
/*
* Copyright 2001-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
*/
/* jvmstat global and subsystem counter name space - enumeration value
* serve as an index into the PerfDataManager::_name_space[] array
* containing the corresponding name space string. Only the top level
* subsystem name spaces are represented here.
*/
enum CounterNS {
// top level name spaces
JAVA_NS,
COM_NS,
SUN_NS,
// subsystem name spaces
JAVA_GC, // Garbage Collection name spaces
COM_GC,
SUN_GC,
JAVA_CI, // Compiler name spaces
COM_CI,
SUN_CI,
JAVA_CLS, // Class Loader name spaces
COM_CLS,
SUN_CLS,
JAVA_RT, // Runtime name spaces
COM_RT,
SUN_RT,
JAVA_OS, // Operating System name spaces
COM_OS,
SUN_OS,
JAVA_THREADS, // Threads System name spaces
COM_THREADS,
SUN_THREADS,
JAVA_PROPERTY, // Java Property name spaces
COM_PROPERTY,
SUN_PROPERTY,
NULL_NS,
COUNTERNS_LAST = NULL_NS
};
/*
* Classes to support access to production performance data
*
* The PerfData class structure is provided for creation, access, and update
* of performance data (a.k.a. instrumentation) in a specific memory region
* which is possibly accessible as shared memory. Although not explicitly
* prevented from doing so, developers should not use the values returned
* by accessor methods to make algorithmic decisions as they are potentially
* extracted from a shared memory region. Although any shared memory region
* created is with appropriate access restrictions, allowing read-write access
* only to the principal that created the JVM, it is believed that a the
* shared memory region facilitates an easier attack path than attacks
* launched through mechanisms such as /proc. For this reason, it is
* recommended that data returned by PerfData accessor methods be used
* cautiously.
*
* There are three variability classifications of performance data
* Constants - value is written to the PerfData memory once, on creation
* Variables - value is modifiable, with no particular restrictions
* Counters - value is monotonically changing (increasing or decreasing)
*
* The performance data items can also have various types. The class
* hierarchy and the structure of the memory region are designed to
* accommodate new types as they are needed. Types are specified in
* terms of Java basic types, which accommodates client applications
* written in the Java programming language. The class hierarchy is:
*
* - PerfData (Abstract)
* - PerfLong (Abstract)
* - PerfLongConstant (alias: PerfConstant)
* - PerfLongVariant (Abstract)
* - PerfLongVariable (alias: PerfVariable)
* - PerfLongCounter (alias: PerfCounter)
*
* - PerfByteArray (Abstract)
* - PerfString (Abstract)
* - PerfStringVariable
* - PerfStringConstant
*
*
* As seen in the class hierarchy, the initially supported types are:
*
* Long - performance data holds a Java long type
* ByteArray - performance data holds an array of Java bytes
* used for holding C++ char arrays.
*
* The String type is derived from the ByteArray type.
*
* A PerfData subtype is not required to provide an implementation for
* each variability classification. For example, the String type provides
* Variable and Constant variablility classifications in the PerfStringVariable
* and PerfStringConstant classes, but does not provide a counter type.
*
* Performance data are also described by a unit of measure. Units allow
* client applications to make reasonable decisions on how to treat
* performance data generically, preventing the need to hard-code the
* specifics of a particular data item in client applications. The current
* set of units are:
*
* None - the data has no units of measure
* Bytes - data is measured in bytes
* Ticks - data is measured in clock ticks
* Events - data is measured in events. For example,
* the number of garbage collection events or the
* number of methods compiled.
* String - data is not numerical. For example,
* the java command line options
* Hertz - data is a frequency
*
* The performance counters also provide a support attribute, indicating
* the stability of the counter as a programmatic interface. The support
* level is also implied by the name space in which the counter is created.
* The counter name space support conventions follow the Java package, class,
* and property support conventions:
*
* java.* - stable, supported interface
* com.sun.* - unstable, supported interface
* sun.* - unstable, unsupported interface
*
* In the above context, unstable is a measure of the interface support
* level, not the implementation stability level.
*
* Currently, instances of PerfData subtypes are considered to have
* a life time equal to that of the VM and are managed by the
* PerfDataManager class. All constructors for the PerfData class and
* its subtypes have protected constructors. Creation of PerfData
* instances is performed by invoking various create methods on the
* PerfDataManager class. Users should not attempt to delete these
* instances as the PerfDataManager class expects to perform deletion
* operations on exit of the VM.
*
* Examples:
*
* Creating performance counter that holds a monotonically increasing
* long data value with units specified in U_Bytes in the "java.gc.*"
* name space.
*
* PerfLongCounter* foo_counter;
*
* foo_counter = PerfDataManager::create_long_counter(JAVA_GC, "foo",
* PerfData::U_Bytes,
* optionalInitialValue,
* CHECK);
* foo_counter->inc();
*
* Creating a performance counter that holds a variably change long
* data value with untis specified in U_Bytes in the "com.sun.ci
* name space.
*
* PerfLongVariable* bar_varible;
* bar_variable = PerfDataManager::create_long_variable(COM_CI, "bar",
.* PerfData::U_Bytes,
* optionalInitialValue,
* CHECK);
*
* bar_variable->inc();
* bar_variable->set_value(0);
*
* Creating a performance counter that holds a constant string value in
* the "sun.cls.*" name space.
*
* PerfDataManager::create_string_constant(SUN_CLS, "foo", string, CHECK);
*
* Although the create_string_constant() factory method returns a pointer
* to the PerfStringConstant object, it can safely be ignored. Developers
* are not encouraged to access the string constant's value via this
* pointer at this time due to security concerns.
*
* Creating a performance counter in an arbitrary name space that holds a
* value that is sampled by the StatSampler periodic task.
*
* PerfDataManager::create_counter("foo.sampled", PerfData::U_Events,
* &my_jlong, CHECK);
*
* In this example, the PerfData pointer can be ignored as the caller
* is relying on the StatSampler PeriodicTask to sample the given
* address at a regular interval. The interval is defined by the
* PerfDataSamplingInterval global variable, and is applyied on
* a system wide basis, not on an per-counter basis.
*
* Creating a performance counter in an arbitrary name space that utilizes
* a helper object to return a value to the StatSampler via the take_sample()
* method.
*
* class MyTimeSampler : public PerfLongSampleHelper {
* public:
* jlong take_sample() { return os::elapsed_counter(); }
* };
*
* PerfDataManager::create_counter(SUN_RT, "helped",
* PerfData::U_Ticks,
* new MyTimeSampler(), CHECK);
*
* In this example, a subtype of PerfLongSampleHelper is instantiated
* and its take_sample() method is overridden to perform whatever
* operation is necessary to generate the data sample. This method
* will be called by the StatSampler at a regular interval, defined
* by the PerfDataSamplingInterval global variable.
*
* As before, PerfSampleHelper is an alias for PerfLongSampleHelper.
*
* For additional uses of PerfData subtypes, see the utility classes
* PerfTraceTime and PerfTraceTimedEvent below.
*
* Always-on non-sampled counters can be created independent of
* the UsePerfData flag. Counters will be created on the c-heap
* if UsePerfData is false.
*
* Until further noice, all PerfData objects should be created and
* manipulated within a guarded block. The guard variable is
* UsePerfData, a product flag set to true by default. This flag may
* be removed from the product in the future.
*
*/
class PerfData : public CHeapObj {
friend class StatSampler; // for access to protected void sample()
friend class PerfDataManager; // for access to protected destructor
public:
// the Variability enum must be kept in synchronization with the
// the com.sun.hotspot.perfdata.Variability class
enum Variability {
V_Constant = 1,
V_Monotonic = 2,
V_Variable = 3,
V_last = V_Variable
};
// the Units enum must be kept in synchronization with the
// the com.sun.hotspot.perfdata.Units class
enum Units {
U_None = 1,
U_Bytes = 2,
U_Ticks = 3,
U_Events = 4,
U_String = 5,
U_Hertz = 6,
U_Last = U_Hertz
};
// Miscellaneous flags
enum Flags {
F_None = 0x0,
F_Supported = 0x1 // interface is supported - java.* and com.sun.*
};
private:
char* _name;
Variability _v;
Units _u;
bool _on_c_heap;
Flags _flags;
PerfDataEntry* _pdep;
protected:
void *_valuep;
PerfData(CounterNS ns, const char* name, Units u, Variability v);
~PerfData();
// create the entry for the PerfData item in the PerfData memory region.
// this region is maintained separately from the PerfData objects to
// facilitate its use by external processes.
void create_entry(BasicType dtype, size_t dsize, size_t dlen = 0);
// sample the data item given at creation time and write its value
// into the its corresponding PerfMemory location.
virtual void sample() = 0;
public:
// returns a boolean indicating the validity of this object.
// the object is valid if and only if memory in PerfMemory
// region was successfully allocated.
inline bool is_valid() { return _valuep != NULL; }
// returns a boolean indicating whether the underlying object
// was allocated in the PerfMemory region or on the C heap.
inline bool is_on_c_heap() { return _on_c_heap; }
// returns a pointer to a char* containing the name of the item.
// The pointer returned is the pointer to a copy of the name
// passed to the constructor, not the pointer to the name in the
// PerfData memory region. This redundancy is maintained for
// security reasons as the PerfMemory region may be in shared
// memory.
const char* name() { return _name; }
// returns the variability classification associated with this item
Variability variability() { return _v; }
// returns the units associated with this item.
Units units() { return _u; }
// returns the flags associated with this item.
Flags flags() { return _flags; }
// returns the address of the data portion of the item in the
// PerfData memory region.
inline void* get_address() { return _valuep; }
// returns the value of the data portion of the item in the
// PerfData memory region formatted as a string.
virtual int format(char* cp, int length) = 0;
};
/*
* PerfLongSampleHelper, and its alias PerfSamplerHelper, is a base class
* for helper classes that rely upon the StatSampler periodic task to
* invoke the take_sample() method and write the value returned to its
* appropriate location in the PerfData memory region.
*/
class PerfLongSampleHelper : public CHeapObj {
public:
virtual jlong take_sample() = 0;
};
typedef PerfLongSampleHelper PerfSampleHelper;
/*
* PerfLong is the base class for the various Long PerfData subtypes.
* it contains implementation details that are common among its derived
* types.
*/
class PerfLong : public PerfData {
protected:
PerfLong(CounterNS ns, const char* namep, Units u, Variability v);
public:
int format(char* buffer, int length);
// returns the value of the data portion of the item in the
// PerfData memory region.
inline jlong get_value() { return *(jlong*)_valuep; }
};
/*
* The PerfLongConstant class, and its alias PerfConstant, implement
* a PerfData subtype that holds a jlong data value that is set upon
* creation of an instance of this class. This class provides no
* methods for changing the data value stored in PerfData memory region.
*/
class PerfLongConstant : public PerfLong {
friend class PerfDataManager; // for access to protected constructor
private:
// hide sample() - no need to sample constants
void sample() { }
protected:
PerfLongConstant(CounterNS ns, const char* namep, Units u,
jlong initial_value=0)
: PerfLong(ns, namep, u, V_Constant) {
if (is_valid()) *(jlong*)_valuep = initial_value;
}
};
typedef PerfLongConstant PerfConstant;
/*
* The PerfLongVariant class, and its alias PerfVariant, implement
* a PerfData subtype that holds a jlong data value that can be modified
* in an unrestricted manner. This class provides the implementation details
* for common functionality among its derived types.
*/
class PerfLongVariant : public PerfLong {
protected:
jlong* _sampled;
PerfLongSampleHelper* _sample_helper;
PerfLongVariant(CounterNS ns, const char* namep, Units u, Variability v,
jlong initial_value=0)
: PerfLong(ns, namep, u, v) {
if (is_valid()) *(jlong*)_valuep = initial_value;
}
PerfLongVariant(CounterNS ns, const char* namep, Units u, Variability v,
jlong* sampled);
PerfLongVariant(CounterNS ns, const char* namep, Units u, Variability v,
PerfLongSampleHelper* sample_helper);
void sample();
public:
inline void inc() { (*(jlong*)_valuep)++; }
inline void inc(jlong val) { (*(jlong*)_valuep) += val; }
inline void add(jlong val) { (*(jlong*)_valuep) += val; }
};
/*
* The PerfLongCounter class, and its alias PerfCounter, implement
* a PerfData subtype that holds a jlong data value that can (should)
* be modified in a monotonic manner. The inc(jlong) and add(jlong)
* methods can be passed negative values to implement a monotonically
* decreasing value. However, we rely upon the programmer to honor
* the notion that this counter always moves in the same direction -
* either increasing or decreasing.
*/
class PerfLongCounter : public PerfLongVariant {
friend class PerfDataManager; // for access to protected constructor
protected:
PerfLongCounter(CounterNS ns, const char* namep, Units u,
jlong initial_value=0)
: PerfLongVariant(ns, namep, u, V_Monotonic,
initial_value) { }
PerfLongCounter(CounterNS ns, const char* namep, Units u, jlong* sampled)
: PerfLongVariant(ns, namep, u, V_Monotonic, sampled) { }
PerfLongCounter(CounterNS ns, const char* namep, Units u,
PerfLongSampleHelper* sample_helper)
: PerfLongVariant(ns, namep, u, V_Monotonic,
sample_helper) { }
};
typedef PerfLongCounter PerfCounter;
/*
* The PerfLongVariable class, and its alias PerfVariable, implement
* a PerfData subtype that holds a jlong data value that can
* be modified in an unrestricted manner.
*/
class PerfLongVariable : public PerfLongVariant {
friend class PerfDataManager; // for access to protected constructor
protected:
PerfLongVariable(CounterNS ns, const char* namep, Units u,
jlong initial_value=0)
: PerfLongVariant(ns, namep, u, V_Variable,
initial_value) { }
PerfLongVariable(CounterNS ns, const char* namep, Units u, jlong* sampled)
: PerfLongVariant(ns, namep, u, V_Variable, sampled) { }
PerfLongVariable(CounterNS ns, const char* namep, Units u,
PerfLongSampleHelper* sample_helper)
: PerfLongVariant(ns, namep, u, V_Variable,
sample_helper) { }
public:
inline void set_value(jlong val) { (*(jlong*)_valuep) = val; }
};
typedef PerfLongVariable PerfVariable;
/*
* The PerfByteArray provides a PerfData subtype that allows the creation
* of a contiguous region of the PerfData memory region for storing a vector
* of bytes. This class is currently intended to be a base class for
* the PerfString class, and cannot be instantiated directly.
*/
class PerfByteArray : public PerfData {
protected:
jint _length;
PerfByteArray(CounterNS ns, const char* namep, Units u, Variability v,
jint length);
};
class PerfString : public PerfByteArray {
protected:
void set_string(const char* s2);
PerfString(CounterNS ns, const char* namep, Variability v, jint length,
const char* initial_value)
: PerfByteArray(ns, namep, U_String, v, length) {
if (is_valid()) set_string(initial_value);
}
public:
int format(char* buffer, int length);
};
/*
* The PerfStringConstant class provides a PerfData sub class that
* allows a null terminated string of single byte characters to be
* stored in the PerfData memory region.
*/
class PerfStringConstant : public PerfString {
friend class PerfDataManager; // for access to protected constructor
private:
// hide sample() - no need to sample constants
void sample() { }
protected:
// Restrict string constant lengths to be <= PerfMaxStringConstLength.
// This prevents long string constants, as can occur with very
// long classpaths or java command lines, from consuming too much
// PerfData memory.
PerfStringConstant(CounterNS ns, const char* namep,
const char* initial_value);
};
/*
* The PerfStringVariable class provides a PerfData sub class that
* allows a null terminated string of single byte character data
* to be stored in PerfData memory region. The string value can be reset
* after initialization. If the string value is >= max_length, then
* it will be truncated to max_length characters. The copied string
* is always null terminated.
*/
class PerfStringVariable : public PerfString {
friend class PerfDataManager; // for access to protected constructor
protected:
// sampling of string variables are not yet supported
void sample() { }
PerfStringVariable(CounterNS ns, const char* namep, jint max_length,
const char* initial_value)
: PerfString(ns, namep, V_Variable, max_length+1,
initial_value) { }
public:
inline void set_value(const char* val) { set_string(val); }
};
/*
* The PerfDataList class is a container class for managing lists
* of PerfData items. The intention of this class is to allow for
* alternative implementations for management of list of PerfData
* items without impacting the code that uses the lists.
*
* The initial implementation is based upon GrowableArray. Searches
* on GrowableArray types is linear in nature and this may become
* a performance issue for creation of PerfData items, particularly
* from Java code where a test for existence is implemented as a
* search over all existing PerfData items.
*
* The abstraction is not complete. A more general container class
* would provide an Iterator abstraction that could be used to
* traverse the lists. This implementation still relys upon integer
* iterators and the at(int index) method. However, the GrowableArray
* is not directly visible outside this class and can be replaced by
* some other implementation, as long as that implementation provides
* a mechanism to iterate over the container by index.
*/
class PerfDataList : public CHeapObj {
private:
// GrowableArray implementation
typedef GrowableArray<PerfData*> PerfDataArray;
PerfDataArray* _set;
// method to search for a instrumentation object by name
static bool by_name(void* name, PerfData* pd);
protected:
// we expose the implementation here to facilitate the clone
// method.
PerfDataArray* get_impl() { return _set; }
public:
// create a PerfDataList with the given initial length
PerfDataList(int length);
// create a PerfDataList as a shallow copy of the given PerfDataList
PerfDataList(PerfDataList* p);
~PerfDataList();
// return the PerfData item indicated by name,
// or NULL if it doesn't exist.
PerfData* find_by_name(const char* name);
// return true if a PerfData item with the name specified in the
// argument exists, otherwise return false.
bool contains(const char* name) { return find_by_name(name) != NULL; }
// return the number of PerfData items in this list
int length() { return _set->length(); }
// add a PerfData item to this list
void append(PerfData *p) { _set->append(p); }
// remove the given PerfData item from this list. When called
// while iterating over the list, this method will result in a
// change in the length of the container. The at(int index)
// method is also impacted by this method as elements with an
// index greater than the index of the element removed by this
// method will be shifted down by one.
void remove(PerfData *p) { _set->remove(p); }
// create a new PerfDataList from this list. The new list is
// a shallow copy of the original list and care should be taken
// with respect to delete operations on the elements of the list
// as the are likely in use by another copy of the list.
PerfDataList* clone();
// for backward compatibility with GrowableArray - need to implement
// some form of iterator to provide a cleaner abstraction for
// iteration over the container.
PerfData* at(int index) { return _set->at(index); }
};
/*
* The PerfDataManager class is responsible for creating PerfData
* subtypes via a set a factory methods and for managing lists
* of the various PerfData types.
*/
class PerfDataManager : AllStatic {
friend class StatSampler; // for access to protected PerfDataList methods
private:
static PerfDataList* _all;
static PerfDataList* _sampled;
static PerfDataList* _constants;
static const char* _name_spaces[];
// add a PerfData item to the list(s) of know PerfData objects
static void add_item(PerfData* p, bool sampled);
protected:
// return the list of all known PerfData items
static PerfDataList* all();
static int count() { return _all->length(); }
// return the list of all known PerfData items that are to be
// sampled by the StatSampler.
static PerfDataList* sampled();
static int sampled_count() { return _sampled->length(); }
// return the list of all known PerfData items that have a
// variability classification of type Constant
static PerfDataList* constants();
static int constants_count() { return _constants->length(); }
public:
// method to check for the existence of a PerfData item with
// the given name.
static bool exists(const char* name) { return _all->contains(name); }
// method to map a CounterNS enumeration to a namespace string
static const char* ns_to_string(CounterNS ns) {
return _name_spaces[ns];
}
// methods to test the interface stability of a given counter namespace
//
static bool is_stable_supported(CounterNS ns) {
return (ns != NULL_NS) && ((ns % 3) == JAVA_NS);
}
static bool is_unstable_supported(CounterNS ns) {
return (ns != NULL_NS) && ((ns % 3) == COM_NS);
}
static bool is_unstable_unsupported(CounterNS ns) {
return (ns == NULL_NS) || ((ns % 3) == SUN_NS);
}
// methods to test the interface stability of a given counter name
//
static bool is_stable_supported(const char* name) {
const char* javadot = "java.";
return strncmp(name, javadot, strlen(javadot)) == 0;
}
static bool is_unstable_supported(const char* name) {
const char* comdot = "com.sun.";
return strncmp(name, comdot, strlen(comdot)) == 0;
}
static bool is_unstable_unsupported(const char* name) {
return !(is_stable_supported(name) && is_unstable_supported(name));
}
// method to construct counter name strings in a given name space.
// The string object is allocated from the Resource Area and calls
// to this method must be made within a ResourceMark.
//
static char* counter_name(const char* name_space, const char* name);
// method to construct name space strings in a given name space.
// The string object is allocated from the Resource Area and calls
// to this method must be made within a ResourceMark.
//
static char* name_space(const char* name_space, const char* sub_space) {
return counter_name(name_space, sub_space);
}
// same as above, but appends the instance number to the name space
//
static char* name_space(const char* name_space, const char* sub_space,
int instance);
static char* name_space(const char* name_space, int instance);
// these methods provide the general interface for creating
// performance data resources. The types of performance data
// resources can be extended by adding additional create<type>
// methods.
// Constant Types
static PerfStringConstant* create_string_constant(CounterNS ns,
const char* name,
const char *s, TRAPS);
static PerfLongConstant* create_long_constant(CounterNS ns,
const char* name,
PerfData::Units u,
jlong val, TRAPS);
// Variable Types
static PerfStringVariable* create_string_variable(CounterNS ns,
const char* name,
int max_length,
const char *s, TRAPS);
static PerfStringVariable* create_string_variable(CounterNS ns,
const char* name,
const char *s, TRAPS) {
return create_string_variable(ns, name, 0, s, CHECK_NULL);
};
static PerfLongVariable* create_long_variable(CounterNS ns,
const char* name,
PerfData::Units u,
jlong ival, TRAPS);
static PerfLongVariable* create_long_variable(CounterNS ns,
const char* name,
PerfData::Units u, TRAPS) {
return create_long_variable(ns, name, u, (jlong)0, CHECK_NULL);
};
static PerfLongVariable* create_long_variable(CounterNS, const char* name,
PerfData::Units u,
jlong* sp, TRAPS);
static PerfLongVariable* create_long_variable(CounterNS ns,
const char* name,
PerfData::Units u,
PerfLongSampleHelper* sh,
TRAPS);
// Counter Types
static PerfLongCounter* create_long_counter(CounterNS ns, const char* name,
PerfData::Units u,
jlong ival, TRAPS);
static PerfLongCounter* create_long_counter(CounterNS ns, const char* name,
PerfData::Units u, TRAPS) {
return create_long_counter(ns, name, u, (jlong)0, CHECK_NULL);
};
static PerfLongCounter* create_long_counter(CounterNS ns, const char* name,
PerfData::Units u, jlong* sp,
TRAPS);
static PerfLongCounter* create_long_counter(CounterNS ns, const char* name,
PerfData::Units u,
PerfLongSampleHelper* sh,
TRAPS);
// these creation methods are provided for ease of use. These allow
// Long performance data types to be created with a shorthand syntax.
static PerfConstant* create_constant(CounterNS ns, const char* name,
PerfData::Units u, jlong val, TRAPS) {
return create_long_constant(ns, name, u, val, CHECK_NULL);
}
static PerfVariable* create_variable(CounterNS ns, const char* name,
PerfData::Units u, jlong ival, TRAPS) {
return create_long_variable(ns, name, u, ival, CHECK_NULL);
}
static PerfVariable* create_variable(CounterNS ns, const char* name,
PerfData::Units u, TRAPS) {
return create_long_variable(ns, name, u, (jlong)0, CHECK_NULL);
}
static PerfVariable* create_variable(CounterNS ns, const char* name,
PerfData::Units u, jlong* sp, TRAPS) {
return create_long_variable(ns, name, u, sp, CHECK_NULL);
}
static PerfVariable* create_variable(CounterNS ns, const char* name,
PerfData::Units u,
PerfSampleHelper* sh, TRAPS) {
return create_long_variable(ns, name, u, sh, CHECK_NULL);
}
static PerfCounter* create_counter(CounterNS ns, const char* name,
PerfData::Units u, jlong ival, TRAPS) {
return create_long_counter(ns, name, u, ival, CHECK_NULL);
}
static PerfCounter* create_counter(CounterNS ns, const char* name,
PerfData::Units u, TRAPS) {
return create_long_counter(ns, name, u, (jlong)0, CHECK_NULL);
}
static PerfCounter* create_counter(CounterNS ns, const char* name,
PerfData::Units u, jlong* sp, TRAPS) {
return create_long_counter(ns, name, u, sp, CHECK_NULL);
}
static PerfCounter* create_counter(CounterNS ns, const char* name,
PerfData::Units u,
PerfSampleHelper* sh, TRAPS) {
return create_long_counter(ns, name, u, sh, CHECK_NULL);
}
static void destroy();
};
// Useful macros to create the performance counters
#define NEWPERFTICKCOUNTER(counter, counter_ns, counter_name) \
{counter = PerfDataManager::create_counter(counter_ns, counter_name, \
PerfData::U_Ticks,CHECK);}
#define NEWPERFEVENTCOUNTER(counter, counter_ns, counter_name) \
{counter = PerfDataManager::create_counter(counter_ns, counter_name, \
PerfData::U_Events,CHECK);}
// Utility Classes
/*
* this class will administer a PerfCounter used as a time accumulator
* for a basic block much like the TraceTime class.
*
* Example:
*
* static PerfCounter* my_time_counter = PerfDataManager::create_counter("my.time.counter", PerfData::U_Ticks, 0LL, CHECK);
*
* {
* PerfTraceTime ptt(my_time_counter);
* // perform the operation you want to measure
* }
*
* Note: use of this class does not need to occur within a guarded
* block. The UsePerfData guard is used with the implementation
* of this class.
*/
class PerfTraceTime : public StackObj {
protected:
elapsedTimer _t;
PerfLongCounter* _timerp;
// pointer to thread-local or global recursion counter variable
int* _recursion_counter;
public:
inline PerfTraceTime(PerfLongCounter* timerp) : _timerp(timerp), _recursion_counter(NULL) {
if (!UsePerfData) return;
_t.start();
}
inline PerfTraceTime(PerfLongCounter* timerp, int* recursion_counter) : _timerp(timerp), _recursion_counter(recursion_counter) {
if (!UsePerfData || (_recursion_counter != NULL &&
(*_recursion_counter)++ > 0)) return;
_t.start();
}
inline void suspend() { if (!UsePerfData) return; _t.stop(); }
inline void resume() { if (!UsePerfData) return; _t.start(); }
inline ~PerfTraceTime() {
if (!UsePerfData || (_recursion_counter != NULL &&
--(*_recursion_counter) > 0)) return;
_t.stop();
_timerp->inc(_t.ticks());
}
};
/* The PerfTraceTimedEvent class is responsible for counting the
* occurrence of some event and measuring the the elapsed time of
* the event in two separate PerfCounter instances.
*
* Example:
*
* static PerfCounter* my_time_counter = PerfDataManager::create_counter("my.time.counter", PerfData::U_Ticks, CHECK);
* static PerfCounter* my_event_counter = PerfDataManager::create_counter("my.event.counter", PerfData::U_Events, CHECK);
*
* {
* PerfTraceTimedEvent ptte(my_time_counter, my_event_counter);
* // perform the operation you want to count and measure
* }
*
* Note: use of this class does not need to occur within a guarded
* block. The UsePerfData guard is used with the implementation
* of this class.
*
*/
class PerfTraceTimedEvent : public PerfTraceTime {
protected:
PerfLongCounter* _eventp;
public:
inline PerfTraceTimedEvent(PerfLongCounter* timerp, PerfLongCounter* eventp): PerfTraceTime(timerp), _eventp(eventp) {
if (!UsePerfData) return;
_eventp->inc();
}
inline PerfTraceTimedEvent(PerfLongCounter* timerp, PerfLongCounter* eventp, int* recursion_counter): PerfTraceTime(timerp, recursion_counter), _eventp(eventp) {
if (!UsePerfData) return;
_eventp->inc();
}
};