Leonid Mesnik f5e4cd7f0d 8372039: post_sampled_object_alloc is called while lock is handled
Reviewed-by: sspitsyn, eosterlund, amenkov
2025-12-02 23:48:58 +00:00

96 lines
3.1 KiB
C++

/*
* Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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*/
#include "jvmti.h"
#include "jvmti_common.hpp"
#include <atomic>
extern "C" {
// SampledObjectAlloc event might be triggered on any thread
static std::atomic<int> events_counter(0);
JNIEXPORT void JNICALL
SampledObjectAlloc(jvmtiEnv *jvmti, JNIEnv* jni, jthread thread, jobject object, jclass object_klass, jlong size) {
events_counter++;
LOG("Sampled object, events_counter = %d\n", events_counter.load());
}
void JNICALL
VMDeath(jvmtiEnv *jvmti, JNIEnv* jni) {
if (events_counter == 0) {
fatal(jni, "SampledObjectAlloc events counter shouldn't be zero");
}
}
jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
jvmtiEnv* jvmti = nullptr;
jvmtiCapabilities caps;
jvmtiEventCallbacks callbacks;
jvmtiError err;
jint res;
LOG("AGENT INIT");
res = jvm->GetEnv((void **) &jvmti, JVMTI_VERSION_9);
if (res != JNI_OK || jvmti == nullptr) {
LOG("Wrong result of a valid call to GetEnv!\n");
return JNI_ERR;
}
memset(&caps, 0, sizeof(caps));
caps.can_generate_sampled_object_alloc_events = 1;
if (jvmti->AddCapabilities(&caps) != JVMTI_ERROR_NONE) {
return JNI_ERR;
}
memset(&callbacks, 0, sizeof(callbacks));
callbacks.SampledObjectAlloc = &SampledObjectAlloc;
callbacks.VMDeath = &VMDeath;
err = jvmti->SetEventCallbacks(&callbacks, sizeof(callbacks));
check_jvmti_error(err, "SetEventCallbacks");
/*
* Interval should be small enough to triggger sampling event while objects are init by VM.
*/
err = jvmti->SetHeapSamplingInterval(10);
check_jvmti_error(err, "SetHeapSamplingInterval");
err = jvmti->SetEventNotificationMode(JVMTI_ENABLE, JVMTI_EVENT_VM_DEATH, nullptr);
check_jvmti_error(err, "SetEventNotificationMode");
err = jvmti->SetEventNotificationMode(JVMTI_ENABLE, JVMTI_EVENT_SAMPLED_OBJECT_ALLOC, nullptr);
check_jvmti_error(err, "SetEventNotificationMode");
return JNI_OK;
}
JNIEXPORT jint JNICALL Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
return Agent_Initialize(jvm, options, reserved);
}
JNIEXPORT jint JNICALL Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
return Agent_Initialize(jvm, options, reserved);
}
}