1 /*
  2  * Copyright (c) 2001, 2024, 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.
 22  *
 23  */
 24 
 25 #include "precompiled.hpp"
 26 #include "classfile/vmSymbols.hpp"
 27 #include "jni.h"
 28 #include "jvm.h"
 29 #include "memory/allocation.inline.hpp"
 30 #include "memory/resourceArea.hpp"
 31 #include "oops/oop.inline.hpp"
 32 #include "runtime/interfaceSupport.inline.hpp"
 33 #include "runtime/perfData.inline.hpp"
 34 #include "runtime/perfMemory.hpp"
 35 
 36 /*
 37  *      Implementation of class jdk.internal.perf.Perf
 38  */
 39 
 40 
 41 #define PERF_ENTRY(result_type, header) \
 42   JVM_ENTRY(result_type, header)
 43 
 44 #define PERF_END JVM_END
 45 
 46 #define PerfWrapper(arg) /* Unimplemented at this time */
 47 
 48 static char* jstr_to_utf(JNIEnv *env, jstring str, TRAPS) {
 49 
 50   char* utfstr = nullptr;
 51 
 52   if (str == nullptr) {
 53     THROW_NULL(vmSymbols::java_lang_NullPointerException());
 54     //throw_new(env,"NullPointerException");
 55   }
 56 
 57   int len = env->GetStringUTFLength(str);
 58   int unicode_len = env->GetStringLength(str);
 59 
 60   utfstr = NEW_RESOURCE_ARRAY(char, len + 1);
 61 
 62   env->GetStringUTFRegion(str, 0, unicode_len, utfstr);
 63 
 64   return utfstr;
 65 }
 66 
 67 PERF_ENTRY(jobject, Perf_Attach(JNIEnv *env, jobject unused, int vmid))
 68 
 69   PerfWrapper("Perf_Attach");
 70 
 71   char* address = nullptr;
 72   size_t capacity = 0;
 73 
 74   // attach to the PerfData memory region for the specified VM
 75   PerfMemory::attach(vmid, &address, &capacity, CHECK_NULL);
 76 
 77   {
 78     ThreadToNativeFromVM ttnfv(thread);
 79     return env->NewDirectByteBuffer(address, (jlong)capacity);
 80   }
 81 
 82 PERF_END
 83 
 84 PERF_ENTRY(void, Perf_Detach(JNIEnv *env, jobject unused, jobject buffer))
 85 
 86   PerfWrapper("Perf_Detach");
 87 
 88   if (!UsePerfData) {
 89     // With -XX:-UsePerfData, detach is just a NOP
 90     return;
 91   }
 92 
 93   void* address = nullptr;
 94   jlong capacity = 0;
 95 
 96   // get buffer address and capacity
 97   {
 98    ThreadToNativeFromVM ttnfv(thread);
 99    address = env->GetDirectBufferAddress(buffer);
100    capacity = env->GetDirectBufferCapacity(buffer);
101   }
102 
103   PerfMemory::detach((char*)address, capacity);
104 
105 PERF_END
106 
107 PERF_ENTRY(jobject, Perf_CreateLong(JNIEnv *env, jobject perf, jstring name,
108            int variability, int units, jlong value))
109 
110   PerfWrapper("Perf_CreateLong");
111 
112   char* name_utf = nullptr;
113 
114   if (units <= 0 || units > PerfData::U_Last) {
115     debug_only(warning("unexpected units argument, units = %d", units));
116     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
117   }
118 
119   ResourceMark rm;
120 
121   {
122     ThreadToNativeFromVM ttnfv(thread);
123 
124     name_utf = jstr_to_utf(env, name, CHECK_NULL);
125   }
126 
127   PerfLong* pl = nullptr;
128 
129   // check that the PerfData name doesn't already exist
130   if (PerfDataManager::exists(name_utf)) {
131     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "PerfLong name already exists");
132   }
133 
134   switch(variability) {
135   case PerfData::V_Constant:
136     pl = PerfDataManager::create_long_constant(NULL_NS, (char *)name_utf,
137                                                (PerfData::Units)units, value,
138                                                CHECK_NULL);
139     break;
140 
141   case PerfData::V_Monotonic:
142     pl = PerfDataManager::create_long_counter(NULL_NS, (char *)name_utf,
143                                                (PerfData::Units)units, value,
144                                                CHECK_NULL);
145     break;
146 
147   case PerfData::V_Variable:
148     pl = PerfDataManager::create_long_variable(NULL_NS, (char *)name_utf,
149                                               (PerfData::Units)units, value,
150                                               CHECK_NULL);
151     break;
152 
153   default: /* Illegal Argument */
154     debug_only(warning("unexpected variability value: %d", variability));
155     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
156     break;
157   }
158 
159   long* lp = (long*)pl->get_address();
160 
161   {
162     ThreadToNativeFromVM ttnfv(thread);
163     return env->NewDirectByteBuffer(lp, sizeof(jlong));
164   }
165 
166 PERF_END
167 
168 PERF_ENTRY(jobject, Perf_CreateByteArray(JNIEnv *env, jobject perf,
169                                          jstring name, jint variability,
170                                          jint units, jbyteArray value,
171                                          jint maxlength))
172 
173   PerfWrapper("Perf_CreateByteArray");
174 
175   // check for valid byte array objects
176   if (name == nullptr || value == nullptr) {
177     THROW_NULL(vmSymbols::java_lang_NullPointerException());
178   }
179 
180   // check for valid variability classification
181   if (variability != PerfData::V_Constant &&
182       variability != PerfData::V_Variable) {
183     debug_only(warning("unexpected variability value: %d", variability));
184     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
185   }
186 
187   // check for valid units
188   if (units != PerfData::U_String) {
189     // only String based ByteArray objects are currently supported
190     debug_only(warning("unexpected units value: %d", variability));
191     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
192   }
193 
194   int value_length;
195   char* name_utf = nullptr;
196   jbyte* value_local = nullptr;
197 
198   ResourceMark rm;
199 
200   {
201     ThreadToNativeFromVM ttnfv(thread);
202 
203     name_utf = jstr_to_utf(env, name, CHECK_NULL);
204 
205     value_length = env->GetArrayLength(value);
206 
207     value_local = NEW_RESOURCE_ARRAY(jbyte, value_length + 1);
208 
209     env->GetByteArrayRegion(value, 0, value_length, value_local);
210   }
211 
212   // check that the counter name doesn't already exist
213   if (PerfDataManager::exists((char*)name_utf)) {
214     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "PerfByteArray name already exists");
215   }
216 
217   PerfByteArray* pbv = nullptr;
218 
219   if (units == PerfData::U_String) {
220 
221     if (variability == PerfData::V_Constant) {
222       // create the string constant
223       pbv = PerfDataManager::create_string_constant(NULL_NS, (char*)name_utf,
224                                                     (char*)value_local,
225                                                     CHECK_NULL);
226 
227       assert(maxlength == value_length, "string constant length should be == maxlength");
228       maxlength = value_length;
229     }
230     else {
231 
232       // create the string variable
233       pbv = PerfDataManager::create_string_variable(NULL_NS, (char*)name_utf,
234                                                     maxlength,
235                                                     (char*)value_local,
236                                                     CHECK_NULL);
237 
238      assert(maxlength >= value_length,"string variable length should be <= maxlength");
239     }
240   }
241 
242   char* cp = (char*)pbv->get_address();
243 
244   {
245     ThreadToNativeFromVM ttnfv(thread);
246     return env->NewDirectByteBuffer(cp, maxlength+1);
247   }
248 
249 PERF_END
250 
251 PERF_ENTRY(jlong, Perf_HighResCounter(JNIEnv *env, jobject perf))
252 
253   PerfWrapper("Perf_HighResCounter");
254 
255   // this should be a method in java.lang.System. This value could
256   // be acquired through access to a PerfData performance counter, but
257   // doing so would require that the PerfData monitoring overhead be
258   // incurred by all Java applications, which is unacceptable.
259 
260   return os::elapsed_counter();
261 
262 PERF_END
263 
264 PERF_ENTRY(jlong, Perf_HighResFrequency(JNIEnv *env, jobject perf))
265 
266   PerfWrapper("Perf_HighResFrequency");
267 
268   // this should be a method in java.lang.System. This value could
269   // be acquired through access to a PerfData performance counter, but
270   // doing so would require that the PerfData monitoring overhead be
271   // incurred by all Java applications, which is unacceptable.
272 
273   return os::elapsed_frequency();
274 
275 PERF_END
276 
277 /// JVM_RegisterPerfMethods
278 
279 #define CC (char*)  /*cast a literal from (const char*)*/
280 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
281 #define BB "Ljava/nio/ByteBuffer;"
282 #define JLS "Ljava/lang/String;"
283 #define CL_ARGS     CC "(" JLS "IIJ)" BB
284 #define CBA_ARGS    CC "(" JLS "II[BI)" BB
285 
286 static JNINativeMethod perfmethods[] = {
287 
288   {CC "attach0",             CC "(I)" BB,         FN_PTR(Perf_Attach)},
289   {CC "detach",              CC "(" BB ")V",      FN_PTR(Perf_Detach)},
290   {CC "createLong",          CL_ARGS,             FN_PTR(Perf_CreateLong)},
291   {CC "createByteArray",     CBA_ARGS,            FN_PTR(Perf_CreateByteArray)},
292   {CC "highResCounter",      CC "()J",            FN_PTR(Perf_HighResCounter)},
293   {CC "highResFrequency",    CC "()J",            FN_PTR(Perf_HighResFrequency)}
294 };
295 
296 #undef CBA_ARGS
297 #undef CL_ARGS
298 #undef JLS
299 #undef BB
300 #undef FN_PTR
301 #undef CC
302 
303 // This one function is exported, used by NativeLookup.
304 JVM_ENTRY(void, JVM_RegisterPerfMethods(JNIEnv *env, jclass perfclass))
305   PerfWrapper("JVM_RegisterPerfMethods");
306   {
307     ThreadToNativeFromVM ttnfv(thread);
308     int ok = env->RegisterNatives(perfclass, perfmethods, sizeof(perfmethods)/sizeof(JNINativeMethod));
309     guarantee(ok == 0, "register perf natives");
310   }
311 JVM_END