1 /*
2 * Copyright (c) 2001, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 #ifndef SHARE_RUNTIME_PERFDATA_HPP
26 #define SHARE_RUNTIME_PERFDATA_HPP
27
28 #include "memory/allocation.hpp"
29 #include "runtime/perfDataTypes.hpp"
30 #include "runtime/perfMemory.hpp"
31 #include "runtime/timer.hpp"
32
33 template <typename T> class GrowableArray;
34
35 /* jvmstat global and subsystem counter name space - enumeration value
36 * serve as an index into the PerfDataManager::_name_space[] array
37 * containing the corresponding name space string. Only the top level
38 * subsystem name spaces are represented here.
39 */
40 enum CounterNS {
41 // top level name spaces
42 JAVA_NS,
43 COM_NS,
44 SUN_NS,
45 // subsystem name spaces
46 JAVA_GC, // Garbage Collection name spaces
47 COM_GC,
48 SUN_GC,
49 JAVA_CI, // Compiler name spaces
50 COM_CI,
51 SUN_CI,
52 JAVA_CLS, // Class Loader name spaces
53 COM_CLS,
54 SUN_CLS,
55 JAVA_RT, // Runtime name spaces
56 COM_RT,
57 SUN_RT,
58 JAVA_OS, // Operating System name spaces
59 COM_OS,
60 SUN_OS,
61 JAVA_THREADS, // Threads System name spaces
62 COM_THREADS,
63 SUN_THREADS,
64 JAVA_THREADS_CPUTIME, // Thread CPU time name spaces
65 COM_THREADS_CPUTIME,
66 SUN_THREADS_CPUTIME,
67 JAVA_PROPERTY, // Java Property name spaces
68 COM_PROPERTY,
69 SUN_PROPERTY,
70 NULL_NS,
71 COUNTERNS_LAST = NULL_NS
72 };
73
74 /*
75 * Classes to support access to production performance data
76 *
77 * The PerfData class structure is provided for creation, access, and update
78 * of performance data (a.k.a. instrumentation) in a specific memory region
79 * which is possibly accessible as shared memory. Although not explicitly
80 * prevented from doing so, developers should not use the values returned
81 * by accessor methods to make algorithmic decisions as they are potentially
82 * extracted from a shared memory region. Although any shared memory region
83 * created is with appropriate access restrictions, allowing read-write access
84 * only to the principal that created the JVM, it is believed that the
85 * shared memory region facilitates an easier attack path than attacks
86 * launched through mechanisms such as /proc. For this reason, it is
87 * recommended that data returned by PerfData accessor methods be used
88 * cautiously.
89 *
90 * There are three variability classifications of performance data
91 * Constants - value is written to the PerfData memory once, on creation
92 * Variables - value is modifiable, with no particular restrictions
93 * Counters - value is monotonically changing (increasing or decreasing)
94 *
95 * The performance data items can also have various types. The class
96 * hierarchy and the structure of the memory region are designed to
97 * accommodate new types as they are needed. Types are specified in
98 * terms of Java basic types, which accommodates client applications
99 * written in the Java programming language. The class hierarchy is:
100 *
101 * - PerfData (Abstract)
102 * - PerfLong (Abstract)
103 * - PerfLongConstant (alias: PerfConstant)
104 * - PerfLongVariant (Abstract)
105 * - PerfLongVariable (alias: PerfVariable)
106 * - PerfLongCounter (alias: PerfCounter)
107 *
108 * - PerfByteArray (Abstract)
109 * - PerfString (Abstract)
110 * - PerfStringVariable
111 * - PerfStringConstant
112 *
113 *
114 * As seen in the class hierarchy, the initially supported types are:
115 *
116 * Long - performance data holds a Java long type
117 * ByteArray - performance data holds an array of Java bytes
118 * used for holding C++ char arrays.
119 *
120 * The String type is derived from the ByteArray type.
121 *
122 * A PerfData subtype is not required to provide an implementation for
123 * each variability classification. For example, the String type provides
124 * Variable and Constant variability classifications in the PerfStringVariable
125 * and PerfStringConstant classes, but does not provide a counter type.
126 *
127 * Performance data are also described by a unit of measure. Units allow
128 * client applications to make reasonable decisions on how to treat
129 * performance data generically, preventing the need to hard-code the
130 * specifics of a particular data item in client applications. The current
131 * set of units are:
132 *
133 * None - the data has no units of measure
134 * Bytes - data is measured in bytes
135 * Ticks - data is measured in clock ticks
136 * Events - data is measured in events. For example,
137 * the number of garbage collection events or the
138 * number of methods compiled.
139 * String - data is not numerical. For example,
140 * the java command line options
141 * Hertz - data is a frequency
142 *
143 * The performance counters also provide a support attribute, indicating
144 * the stability of the counter as a programmatic interface. The support
145 * level is also implied by the name space in which the counter is created.
146 * The counter name space support conventions follow the Java package, class,
147 * and property support conventions:
148 *
149 * java.* - stable, supported interface
150 * com.sun.* - unstable, supported interface
151 * sun.* - unstable, unsupported interface
152 *
153 * In the above context, unstable is a measure of the interface support
154 * level, not the implementation stability level.
155 *
156 * Currently, instances of PerfData subtypes are considered to have
157 * a life time equal to that of the VM and are managed by the
158 * PerfDataManager class. All constructors for the PerfData class and
159 * its subtypes have protected constructors. Creation of PerfData
160 * instances is performed by invoking various create methods on the
161 * PerfDataManager class. Users should not attempt to delete these
162 * instances as the PerfDataManager class expects to perform deletion
163 * operations on exit of the VM.
164 *
165 * Examples:
166 *
167 * Creating performance counter that holds a monotonically increasing
168 * long data value with units specified in U_Bytes in the "java.gc.*"
169 * name space.
170 *
171 * PerfLongCounter* foo_counter;
172 *
173 * foo_counter = PerfDataManager::create_long_counter(JAVA_GC, "foo",
174 * PerfData::U_Bytes,
175 * optionalInitialValue,
176 * CHECK);
177 * foo_counter->inc();
178 *
179 * Creating a performance counter that holds a variably change long
180 * data value with units specified in U_Bytes in the "com.sun.ci
181 * name space.
182 *
183 * PerfLongVariable* bar_variable;
184 * bar_variable = PerfDataManager::create_long_variable(COM_CI, "bar",
185 .* PerfData::U_Bytes,
186 * optionalInitialValue,
187 * CHECK);
188 *
189 * bar_variable->inc();
190 * bar_variable->set_value(0);
191 *
192 * Creating a performance counter that holds a constant string value in
193 * the "sun.cls.*" name space.
194 *
195 * PerfDataManager::create_string_constant(SUN_CLS, "foo", string, CHECK);
196 *
197 * Although the create_string_constant() factory method returns a pointer
198 * to the PerfStringConstant object, it can safely be ignored. Developers
199 * are not encouraged to access the string constant's value via this
200 * pointer at this time due to security concerns.
201 *
202 * Creating a performance counter in an arbitrary name space that holds a
203 * value that is sampled by the StatSampler periodic task.
204 *
205 * PerfDataManager::create_counter("foo.sampled", PerfData::U_Events,
206 * &my_jlong, CHECK);
207 *
208 * In this example, the PerfData pointer can be ignored as the caller
209 * is relying on the StatSampler PeriodicTask to sample the given
210 * address at a regular interval. The interval is defined by the
211 * PerfDataSamplingInterval global variable, and is applied on
212 * a system wide basis, not on an per-counter basis.
213 *
214 * Creating a performance counter in an arbitrary name space that utilizes
215 * a helper object to return a value to the StatSampler via the take_sample()
216 * method.
217 *
218 * class MyTimeSampler : public PerfLongSampleHelper {
219 * public:
220 * jlong take_sample() { return os::elapsed_counter(); }
221 * };
222 *
223 * PerfDataManager::create_counter(SUN_RT, "helped",
224 * PerfData::U_Ticks,
225 * new MyTimeSampler(), CHECK);
226 *
227 * In this example, a subtype of PerfLongSampleHelper is instantiated
228 * and its take_sample() method is overridden to perform whatever
229 * operation is necessary to generate the data sample. This method
230 * will be called by the StatSampler at a regular interval, defined
231 * by the PerfDataSamplingInterval global variable.
232 *
233 * As before, PerfSampleHelper is an alias for PerfLongSampleHelper.
234 *
235 * For additional uses of PerfData subtypes, see the utility classes
236 * PerfTraceTime and PerfTraceTimedEvent below.
237 *
238 * Always-on non-sampled counters can be created independent of
239 * the UsePerfData flag. Counters will be created on the c-heap
240 * if UsePerfData is false.
241 *
242 * Until further notice, all PerfData objects should be created and
243 * manipulated within a guarded block. The guard variable is
244 * UsePerfData, a product flag set to true by default. This flag may
245 * be removed from the product in the future.
246 *
247 */
248 class PerfData : public CHeapObj<mtInternal> {
249
250 friend class StatSampler; // for access to protected void sample()
251 friend class PerfDataManager; // for access to protected destructor
252 friend class VMStructs;
253
254 public:
255
256 // the Variability enum must be kept in synchronization with the
257 // the com.sun.hotspot.perfdata.Variability class
258 enum Variability {
259 V_Constant = 1,
260 V_Monotonic = 2,
261 V_Variable = 3,
262 V_last = V_Variable
263 };
264
265 // the Units enum must be kept in synchronization with the
266 // the com.sun.hotspot.perfdata.Units class
267 enum Units {
268 U_None = 1,
269 U_Bytes = 2,
270 U_Ticks = 3,
271 U_Events = 4,
272 U_String = 5,
273 U_Hertz = 6,
274 U_Last = U_Hertz
275 };
276
277 // Miscellaneous flags
278 enum Flags {
279 F_None = 0x0,
280 F_Supported = 0x1 // interface is supported - java.* and com.sun.*
281 };
282
283 private:
284 char* _name;
285 Variability _v;
286 Units _u;
287 bool _on_c_heap;
288 Flags _flags;
289
290 PerfDataEntry* _pdep;
291
292 protected:
293
294 void *_valuep;
295
296 PerfData(CounterNS ns, const char* name, Units u, Variability v);
297 virtual ~PerfData();
298
299 // create the entry for the PerfData item in the PerfData memory region.
300 // this region is maintained separately from the PerfData objects to
301 // facilitate its use by external processes.
302 void create_entry(BasicType dtype, size_t dsize, size_t dlen = 0);
303
304 // sample the data item given at creation time and write its value
305 // into the its corresponding PerfMemory location.
306 virtual void sample() = 0;
307
308 public:
309
310 // returns a boolean indicating the validity of this object.
311 // the object is valid if and only if memory in PerfMemory
312 // region was successfully allocated.
313 inline bool is_valid() { return _valuep != nullptr; }
314
315 // returns a boolean indicating whether the underlying object
316 // was allocated in the PerfMemory region or on the C heap.
317 inline bool is_on_c_heap() { return _on_c_heap; }
318
319 // returns a pointer to a char* containing the name of the item.
320 // The pointer returned is the pointer to a copy of the name
321 // passed to the constructor, not the pointer to the name in the
322 // PerfData memory region. This redundancy is maintained for
323 // security reasons as the PerfMemory region may be in shared
324 // memory.
325 const char* name() const { return _name; }
326 bool name_equals(const char* name) const;
327
328 // returns the variability classification associated with this item
329 Variability variability() { return _v; }
330
331 // returns the units associated with this item.
332 Units units() { return _u; }
333
334 // returns the flags associated with this item.
335 Flags flags() { return _flags; }
336
337 // returns the address of the data portion of the item in the
338 // PerfData memory region.
339 inline void* get_address() { return _valuep; }
340 };
341
342 /*
343 * PerfLongSampleHelper, and its alias PerfSamplerHelper, is a base class
344 * for helper classes that rely upon the StatSampler periodic task to
345 * invoke the take_sample() method and write the value returned to its
346 * appropriate location in the PerfData memory region.
347 */
348 class PerfLongSampleHelper : public CHeapObj<mtInternal> {
349 public:
350 virtual jlong take_sample() = 0;
351 };
352
353 /*
354 * PerfLong is the base class for the various Long PerfData subtypes.
355 * it contains implementation details that are common among its derived
356 * types.
357 */
358 class PerfLong : public PerfData {
359
360 protected:
361
362 PerfLong(CounterNS ns, const char* namep, Units u, Variability v);
363
364 public:
365 // returns the value of the data portion of the item in the
366 // PerfData memory region.
367 inline jlong get_value() { return *(jlong*)_valuep; }
368 };
369
370 /*
371 * The PerfLongConstant class, and its alias PerfConstant, implement
372 * a PerfData subtype that holds a jlong data value that is set upon
373 * creation of an instance of this class. This class provides no
374 * methods for changing the data value stored in PerfData memory region.
375 */
376 class PerfLongConstant : public PerfLong {
377
378 friend class PerfDataManager; // for access to protected constructor
379
380 private:
381 // hide sample() - no need to sample constants
382 void sample() { }
383
384 protected:
385
386 PerfLongConstant(CounterNS ns, const char* namep, Units u,
387 jlong initial_value=0)
388 : PerfLong(ns, namep, u, V_Constant) {
389
390 if (is_valid()) *(jlong*)_valuep = initial_value;
391 }
392 };
393
394 /*
395 * The PerfLongVariant class, and its alias PerfVariant, implement
396 * a PerfData subtype that holds a jlong data value that can be modified
397 * in an unrestricted manner. This class provides the implementation details
398 * for common functionality among its derived types.
399 */
400 class PerfLongVariant : public PerfLong {
401
402 protected:
403 PerfLongSampleHelper* _sample_helper;
404
405 PerfLongVariant(CounterNS ns, const char* namep, Units u, Variability v,
406 jlong initial_value=0)
407 : PerfLong(ns, namep, u, v) {
408 if (is_valid()) *(jlong*)_valuep = initial_value;
409 }
410
411 PerfLongVariant(CounterNS ns, const char* namep, Units u, Variability v,
412 PerfLongSampleHelper* sample_helper);
413
414 void sample();
415
416 public:
417 inline void inc() { (*(jlong*)_valuep)++; }
418 inline void inc(jlong val) { (*(jlong*)_valuep) += val; }
419 inline void dec(jlong val) { inc(-val); }
420 };
421
422 /*
423 * The PerfLongCounter class, and its alias PerfCounter, implement
424 * a PerfData subtype that holds a jlong data value that can (should)
425 * be modified in a monotonic manner. The inc(jlong) and add(jlong)
426 * methods can be passed negative values to implement a monotonically
427 * decreasing value. However, we rely upon the programmer to honor
428 * the notion that this counter always moves in the same direction -
429 * either increasing or decreasing.
430 */
431 class PerfLongCounter : public PerfLongVariant {
432
433 friend class PerfDataManager; // for access to protected constructor
434
435 protected:
436
437 PerfLongCounter(CounterNS ns, const char* namep, Units u,
438 jlong initial_value=0)
439 : PerfLongVariant(ns, namep, u, V_Monotonic,
440 initial_value) { }
441
442 PerfLongCounter(CounterNS ns, const char* namep, Units u,
443 PerfLongSampleHelper* sample_helper)
444 : PerfLongVariant(ns, namep, u, V_Monotonic,
445 sample_helper) { }
446 };
447
448 /*
449 * The PerfLongVariable class, and its alias PerfVariable, implement
450 * a PerfData subtype that holds a jlong data value that can
451 * be modified in an unrestricted manner.
452 */
453 class PerfLongVariable : public PerfLongVariant {
454
455 friend class PerfDataManager; // for access to protected constructor
456
457 protected:
458
459 PerfLongVariable(CounterNS ns, const char* namep, Units u,
460 jlong initial_value=0)
461 : PerfLongVariant(ns, namep, u, V_Variable,
462 initial_value) { }
463
464 PerfLongVariable(CounterNS ns, const char* namep, Units u,
465 PerfLongSampleHelper* sample_helper)
466 : PerfLongVariant(ns, namep, u, V_Variable,
467 sample_helper) { }
468
469 public:
470 inline void set_value(jlong val) { (*(jlong*)_valuep) = val; }
471 };
472
473 /*
474 * The PerfByteArray provides a PerfData subtype that allows the creation
475 * of a contiguous region of the PerfData memory region for storing a vector
476 * of bytes. This class is currently intended to be a base class for
477 * the PerfString class, and cannot be instantiated directly.
478 */
479 class PerfByteArray : public PerfData {
480
481 protected:
482 jint _length;
483
484 PerfByteArray(CounterNS ns, const char* namep, Units u, Variability v,
485 jint length);
486 };
487
488 class PerfString : public PerfByteArray {
489
490 protected:
491
492 void set_string(const char* s2);
493
494 PerfString(CounterNS ns, const char* namep, Variability v, jint length,
495 const char* initial_value)
496 : PerfByteArray(ns, namep, U_String, v, length) {
497 if (is_valid()) set_string(initial_value);
498 }
499
500 };
501
502 /*
503 * The PerfStringConstant class provides a PerfData sub class that
504 * allows a null terminated string of single byte characters to be
505 * stored in the PerfData memory region.
506 */
507 class PerfStringConstant : public PerfString {
508
509 friend class PerfDataManager; // for access to protected constructor
510
511 private:
512
513 // hide sample() - no need to sample constants
514 void sample() { }
515
516 protected:
517
518 // Restrict string constant lengths to be <= PerfMaxStringConstLength.
519 // This prevents long string constants, as can occur with very
520 // long classpaths or java command lines, from consuming too much
521 // PerfData memory.
522 PerfStringConstant(CounterNS ns, const char* namep,
523 const char* initial_value);
524 };
525
526 /*
527 * The PerfStringVariable class provides a PerfData sub class that
528 * allows a null terminated string of single byte character data
529 * to be stored in PerfData memory region. The string value can be reset
530 * after initialization. If the string value is >= max_length, then
531 * it will be truncated to max_length characters. The copied string
532 * is always null terminated.
533 */
534 class PerfStringVariable : public PerfString {
535
536 friend class PerfDataManager; // for access to protected constructor
537
538 protected:
539
540 // sampling of string variables are not yet supported
541 void sample() { }
542
543 PerfStringVariable(CounterNS ns, const char* namep, jint max_length,
544 const char* initial_value)
545 : PerfString(ns, namep, V_Variable, max_length+1,
546 initial_value) { }
547
548 public:
549 inline void set_value(const char* val) { set_string(val); }
550 };
551
552
553 /*
554 * The PerfDataList class is a container class for managing lists
555 * of PerfData items. The intention of this class is to allow for
556 * alternative implementations for management of list of PerfData
557 * items without impacting the code that uses the lists.
558 *
559 * The initial implementation is based upon GrowableArray. Searches
560 * on GrowableArray types is linear in nature and this may become
561 * a performance issue for creation of PerfData items, particularly
562 * from Java code where a test for existence is implemented as a
563 * search over all existing PerfData items.
564 *
565 * The abstraction is not complete. A more general container class
566 * would provide an Iterator abstraction that could be used to
567 * traverse the lists. This implementation still relies upon integer
568 * iterators and the at(int index) method. However, the GrowableArray
569 * is not directly visible outside this class and can be replaced by
570 * some other implementation, as long as that implementation provides
571 * a mechanism to iterate over the container by index.
572 */
573 class PerfDataList : public CHeapObj<mtInternal> {
574
575 private:
576
577 // GrowableArray implementation
578 typedef GrowableArray<PerfData*> PerfDataArray;
579
580 PerfDataArray* _set;
581
582 // method to search for a instrumentation object by name
583 static bool by_name(const char* name, PerfData* pd);
584
585 protected:
586 // we expose the implementation here to facilitate the clone
587 // method.
588 PerfDataArray* get_impl() { return _set; }
589
590 public:
591
592 // create a PerfDataList with the given initial length
593 PerfDataList(int length);
594
595 // create a PerfDataList as a shallow copy of the given PerfDataList
596 PerfDataList(PerfDataList* p);
597
598 ~PerfDataList();
599
600 // return the PerfData item indicated by name,
601 // or null if it doesn't exist.
602 PerfData* find_by_name(const char* name);
603
604 // return true if a PerfData item with the name specified in the
605 // argument exists, otherwise return false.
606 bool contains(const char* name) { return find_by_name(name) != nullptr; }
607
608 // return the number of PerfData items in this list
609 inline int length();
610
611 // add a PerfData item to this list
612 inline void append(PerfData *p);
613
614 // create a new PerfDataList from this list. The new list is
615 // a shallow copy of the original list and care should be taken
616 // with respect to delete operations on the elements of the list
617 // as the are likely in use by another copy of the list.
618 PerfDataList* clone();
619
620 // for backward compatibility with GrowableArray - need to implement
621 // some form of iterator to provide a cleaner abstraction for
622 // iteration over the container.
623 inline PerfData* at(int index);
624 };
625
626
627 /*
628 * The PerfDataManager class is responsible for creating PerfData
629 * subtypes via a set a factory methods and for managing lists
630 * of the various PerfData types.
631 */
632 class PerfDataManager : AllStatic {
633
634 friend class StatSampler; // for access to protected PerfDataList methods
635
636 private:
637 static PerfDataList* _all;
638 static PerfDataList* _sampled;
639 static PerfDataList* _constants;
640 static const char* _name_spaces[];
641 static volatile bool _has_PerfData;
642
643 // add a PerfData item to the list(s) of know PerfData objects
644 static void add_item(PerfData* p, bool sampled);
645
646 protected:
647
648 // return the list of all known PerfData items that are to be
649 // sampled by the StatSampler.
650 static PerfDataList* sampled();
651
652 public:
653
654 // method to check for the existence of a PerfData item with
655 // the given name.
656 static inline bool exists(const char* name);
657
658 // method to map a CounterNS enumeration to a namespace string
659 static const char* ns_to_string(CounterNS ns) {
660 return _name_spaces[ns];
661 }
662
663 // methods to test the interface stability of a given counter namespace
664 //
665 static bool is_stable_supported(CounterNS ns) {
666 return (ns != NULL_NS) && ((ns % 3) == JAVA_NS);
667 }
668 static bool is_unstable_supported(CounterNS ns) {
669 return (ns != NULL_NS) && ((ns % 3) == COM_NS);
670 }
671
672 // methods to test the interface stability of a given counter name
673 //
674 static bool is_stable_supported(const char* name) {
675 const char* javadot = "java.";
676 return strncmp(name, javadot, strlen(javadot)) == 0;
677 }
678 static bool is_unstable_supported(const char* name) {
679 const char* comdot = "com.sun.";
680 return strncmp(name, comdot, strlen(comdot)) == 0;
681 }
682
683 // method to construct counter name strings in a given name space.
684 // The string object is allocated from the Resource Area and calls
685 // to this method must be made within a ResourceMark.
686 //
687 static char* counter_name(const char* name_space, const char* name);
688
689 // method to construct name space strings in a given name space.
690 // The string object is allocated from the Resource Area and calls
691 // to this method must be made within a ResourceMark.
692 //
693 static char* name_space(const char* name_space, const char* sub_space) {
694 return counter_name(name_space, sub_space);
695 }
696
697 // same as above, but appends the instance number to the name space
698 //
699 static char* name_space(const char* name_space, const char* sub_space,
700 int instance);
701 static char* name_space(const char* name_space, int instance);
702
703
704 // these methods provide the general interface for creating
705 // performance data resources. The types of performance data
706 // resources can be extended by adding additional create<type>
707 // methods.
708
709 // Constant Types
710 static PerfStringConstant* create_string_constant(CounterNS ns,
711 const char* name,
712 const char *s, TRAPS);
713
714 static PerfLongConstant* create_long_constant(CounterNS ns,
715 const char* name,
716 PerfData::Units u,
717 jlong val, TRAPS);
718
719
720 // Variable Types
721 static PerfStringVariable* create_string_variable(CounterNS ns,
722 const char* name,
723 int max_length,
724 const char *s, TRAPS);
725
726 static PerfLongVariable* create_long_variable(CounterNS ns,
727 const char* name,
728 PerfData::Units u,
729 jlong ival, TRAPS);
730
731 static PerfLongVariable* create_long_variable(CounterNS ns,
732 const char* name,
733 PerfData::Units u, TRAPS) {
734 return create_long_variable(ns, name, u, (jlong)0, THREAD);
735 };
736
737 static PerfLongVariable* create_long_variable(CounterNS ns,
738 const char* name,
739 PerfData::Units u,
740 PerfLongSampleHelper* sh,
741 TRAPS);
742
743
744 // Counter Types
745 static PerfLongCounter* create_long_counter(CounterNS ns, const char* name,
746 PerfData::Units u,
747 jlong ival, TRAPS);
748
749 static PerfLongCounter* create_long_counter(CounterNS ns, const char* name,
750 PerfData::Units u,
751 PerfLongSampleHelper* sh,
752 TRAPS);
753
754
755 // these creation methods are provided for ease of use. These allow
756 // Long performance data types to be created with a shorthand syntax.
757
758 static PerfConstant* create_constant(CounterNS ns, const char* name,
759 PerfData::Units u, jlong val, TRAPS) {
760 return create_long_constant(ns, name, u, val, THREAD);
761 }
762
763 static PerfVariable* create_variable(CounterNS ns, const char* name,
764 PerfData::Units u, jlong ival, TRAPS) {
765 return create_long_variable(ns, name, u, ival, THREAD);
766 }
767
768 static PerfVariable* create_variable(CounterNS ns, const char* name,
769 PerfData::Units u, TRAPS) {
770 return create_long_variable(ns, name, u, (jlong)0, THREAD);
771 }
772
773 static PerfVariable* create_variable(CounterNS ns, const char* name,
774 PerfData::Units u,
775 PerfSampleHelper* sh, TRAPS) {
776 return create_long_variable(ns, name, u, sh, THREAD);
777 }
778
779 static PerfCounter* create_counter(CounterNS ns, const char* name,
780 PerfData::Units u, TRAPS) {
781 return create_long_counter(ns, name, u, (jlong)0, THREAD);
782 }
783
784 static PerfCounter* create_counter(CounterNS ns, const char* name,
785 PerfData::Units u,
786 PerfSampleHelper* sh, TRAPS) {
787 return create_long_counter(ns, name, u, sh, THREAD);
788 }
789
790 static void destroy();
791 static bool has_PerfData() { return _has_PerfData; }
792 };
793
794 // Useful macros to create the performance counters
795 #define NEWPERFTICKCOUNTER(counter, counter_ns, counter_name) \
796 {counter = PerfDataManager::create_counter(counter_ns, counter_name, \
797 PerfData::U_Ticks,CHECK);}
798
799 #define NEWPERFEVENTCOUNTER(counter, counter_ns, counter_name) \
800 {counter = PerfDataManager::create_counter(counter_ns, counter_name, \
801 PerfData::U_Events,CHECK);}
802
803 #define NEWPERFBYTECOUNTER(counter, counter_ns, counter_name) \
804 {counter = PerfDataManager::create_counter(counter_ns, counter_name, \
805 PerfData::U_Bytes,CHECK);}
806
807 // Utility Classes
808
809 /*
810 * this class will administer a PerfCounter used as a time accumulator
811 * for a basic block much like the TraceTime class.
812 *
813 * Example:
814 *
815 * static PerfCounter* my_time_counter = PerfDataManager::create_counter("my.time.counter", PerfData::U_Ticks, 0LL, CHECK);
816 *
817 * {
818 * PerfTraceTime ptt(my_time_counter);
819 * // perform the operation you want to measure
820 * }
821 *
822 * Note: use of this class does not need to occur within a guarded
823 * block. The UsePerfData guard is used with the implementation
824 * of this class.
825 */
826 class PerfTraceTime : public StackObj {
827
828 protected:
829 elapsedTimer _t;
830 PerfLongCounter* _timerp;
831
832 public:
833 inline PerfTraceTime(PerfLongCounter* timerp) : _timerp(timerp) {
834 if (!UsePerfData || timerp == nullptr) { return; }
835 _t.start();
836 }
837
838 const char* name() const {
839 assert(_timerp != nullptr, "sanity");
840 return _timerp->name();
841 }
842
843 ~PerfTraceTime() {
844 if (!UsePerfData || !_t.is_active()) { return; }
845 _t.stop();
846 _timerp->inc(_t.ticks());
847 }
848 };
849
850 /* The PerfTraceTimedEvent class is responsible for counting the
851 * occurrence of some event and measuring the elapsed time of
852 * the event in two separate PerfCounter instances.
853 *
854 * Example:
855 *
856 * static PerfCounter* my_time_counter = PerfDataManager::create_counter("my.time.counter", PerfData::U_Ticks, CHECK);
857 * static PerfCounter* my_event_counter = PerfDataManager::create_counter("my.event.counter", PerfData::U_Events, CHECK);
858 *
859 * {
860 * PerfTraceTimedEvent ptte(my_time_counter, my_event_counter);
861 * // perform the operation you want to count and measure
862 * }
863 *
864 * Note: use of this class does not need to occur within a guarded
865 * block. The UsePerfData guard is used with the implementation
866 * of this class.
867 *
868 */
869 class PerfTraceTimedEvent : public PerfTraceTime {
870
871 protected:
872 PerfLongCounter* _eventp;
873
874 public:
875 inline PerfTraceTimedEvent(PerfLongCounter* timerp, PerfLongCounter* eventp): PerfTraceTime(timerp), _eventp(eventp) {
876 if (!UsePerfData || timerp == nullptr) { return; }
877 _eventp->inc();
878 }
879
880 };
881
882 #endif // SHARE_RUNTIME_PERFDATA_HPP