Add extension and agent for dumping internal jvmti plugin data.
When debugging openjdkjvmti plugin issues it can be useful to dump
internal state somewhere it can be examined. This adds a new extension
method that will let agents get a view of the deopt state of the
plugin and an agent that prints this information to LOG(INFO) on
SIGQUIT.
Test: ./test.py --host
Change-Id: Ia265a5bcca31a2df5ac930ddc2ecffb57d3db911
diff --git a/openjdkjvmti/deopt_manager.cc b/openjdkjvmti/deopt_manager.cc
index ee77b7b..ec29f2c 100644
--- a/openjdkjvmti/deopt_manager.cc
+++ b/openjdkjvmti/deopt_manager.cc
@@ -30,6 +30,8 @@
*/
#include <functional>
+#include <iosfwd>
+#include <mutex>
#include "deopt_manager.h"
@@ -109,6 +111,53 @@
callbacks->RemoveMethodInspectionCallback(&inspection_callback_);
}
+void DeoptManager::DumpDeoptInfo(art::Thread* self, std::ostream& stream) {
+ art::ScopedObjectAccess soa(self);
+ art::MutexLock mutll(self, *art::Locks::thread_list_lock_);
+ art::MutexLock mudsl(self, deoptimization_status_lock_);
+ art::MutexLock mubsl(self, breakpoint_status_lock_);
+ stream << "Deoptimizer count: " << deopter_count_ << "\n";
+ stream << "Global deopt count: " << global_deopt_count_ << "\n";
+ stream << "Can perform OSR: " << !set_local_variable_called_.load() << "\n";
+ for (const auto& [bp, loc] : this->breakpoint_status_) {
+ stream << "Breakpoint: " << bp->PrettyMethod() << " @ 0x" << std::hex << loc << "\n";
+ }
+ struct DumpThreadDeoptCount : public art::Closure {
+ public:
+ DumpThreadDeoptCount(std::ostream& stream, std::mutex& mu)
+ : cnt_(0), stream_(stream), mu_(mu) {}
+ void Run(art::Thread* self) override {
+ {
+ std::lock_guard<std::mutex> lg(mu_);
+ std::string name;
+ self->GetThreadName(name);
+ stream_ << "Thread " << name << " (id: " << std::dec << self->GetThreadId()
+ << ") force interpreter count " << self->ForceInterpreterCount() << "\n";
+ }
+ // Increment this after unlocking the mutex so we won't race its destructor.
+ cnt_++;
+ }
+
+ void WaitForCount(size_t threads) {
+ while (cnt_.load() != threads) {
+ sched_yield();
+ }
+ }
+
+ private:
+ std::atomic<size_t> cnt_;
+ std::ostream& stream_;
+ std::mutex& mu_;
+ };
+
+ std::mutex mu;
+ DumpThreadDeoptCount dtdc(stream, mu);
+ auto func = [](art::Thread* thread, void* ctx) {
+ reinterpret_cast<DumpThreadDeoptCount*>(ctx)->Run(thread);
+ };
+ art::Runtime::Current()->GetThreadList()->ForEach(func, &dtdc);
+}
+
void DeoptManager::FinishSetup() {
art::Thread* self = art::Thread::Current();
art::MutexLock mu(self, deoptimization_status_lock_);
@@ -366,8 +415,7 @@
return err;
}
// We don't need additional locking here because we hold the Thread_list_lock_.
- target->SetForceInterpreterCount(target->ForceInterpreterCount() + 1);
- if (target->ForceInterpreterCount() == 1) {
+ if (target->IncrementForceInterpreterCount() == 1) {
struct DeoptClosure : public art::Closure {
public:
explicit DeoptClosure(DeoptManager* man) : man_(man) {}
diff --git a/openjdkjvmti/deopt_manager.h b/openjdkjvmti/deopt_manager.h
index 4c4a774..73a64be 100644
--- a/openjdkjvmti/deopt_manager.h
+++ b/openjdkjvmti/deopt_manager.h
@@ -33,6 +33,7 @@
#define ART_OPENJDKJVMTI_DEOPT_MANAGER_H_
#include <atomic>
+#include <iosfwd>
#include <unordered_map>
#include "base/mutex.h"
@@ -78,6 +79,8 @@
void Setup();
void Shutdown();
+ void DumpDeoptInfo(art::Thread* self, std::ostream& stream);
+
void RemoveDeoptimizationRequester() REQUIRES(!deoptimization_status_lock_,
!art::Roles::uninterruptible_);
void AddDeoptimizationRequester() REQUIRES(!deoptimization_status_lock_,
diff --git a/openjdkjvmti/ti_dump.cc b/openjdkjvmti/ti_dump.cc
index c9abb71..caf24fa 100644
--- a/openjdkjvmti/ti_dump.cc
+++ b/openjdkjvmti/ti_dump.cc
@@ -32,9 +32,11 @@
#include "ti_dump.h"
#include <limits>
+#include <sstream>
#include "art_jvmti.h"
#include "base/mutex.h"
+#include "deopt_manager.h"
#include "events-inl.h"
#include "runtime_callbacks.h"
#include "scoped_thread_state_change-inl.h"
@@ -70,4 +72,22 @@
art::Runtime::Current()->GetRuntimeCallbacks()->RemoveRuntimeSigQuitCallback(&gDumpCallback);
}
+jvmtiError DumpUtil::DumpInternalState(jvmtiEnv *jvmti, char **data) {
+ art::Thread* self = art::Thread::Current();
+ if (jvmti == nullptr || self == nullptr) {
+ return ERR(INVALID_ENVIRONMENT);
+ } else if (data == nullptr) {
+ return ERR(NULL_POINTER);
+ }
+
+ std::stringstream ss;
+ // TODO Add more stuff on here.
+ DeoptManager::Get()->DumpDeoptInfo(self, ss);
+
+ jvmtiError err = OK;
+ JvmtiUniquePtr<char[]> res = CopyString(jvmti, ss.str().c_str(), &err);
+ *data = res.release();
+ return err;
+}
+
} // namespace openjdkjvmti
diff --git a/openjdkjvmti/ti_dump.h b/openjdkjvmti/ti_dump.h
index 323bf56..c382b36 100644
--- a/openjdkjvmti/ti_dump.h
+++ b/openjdkjvmti/ti_dump.h
@@ -43,6 +43,8 @@
public:
static void Register(EventHandler* event_handler);
static void Unregister();
+
+ static jvmtiError DumpInternalState(jvmtiEnv* jvmti, char** data);
};
} // namespace openjdkjvmti
diff --git a/openjdkjvmti/ti_extension.cc b/openjdkjvmti/ti_extension.cc
index 5d39884..f12cb0a 100644
--- a/openjdkjvmti/ti_extension.cc
+++ b/openjdkjvmti/ti_extension.cc
@@ -38,6 +38,7 @@
#include "ti_allocator.h"
#include "ti_class.h"
#include "ti_ddms.h"
+#include "ti_dump.h"
#include "ti_heap.h"
#include "ti_logging.h"
#include "ti_monitor.h"
@@ -312,6 +313,20 @@
return error;
}
+ // DumpInternalState
+ error = add_extension(
+ reinterpret_cast<jvmtiExtensionFunction>(DumpUtil::DumpInternalState),
+ "com.android.art.misc.get_plugin_internal_state",
+ "Gets internal state about the plugin and serializes it to the given msg. "
+ "There is no particular format to this message beyond being human readable.",
+ {
+ { "msg", JVMTI_KIND_ALLOC_BUF, JVMTI_TYPE_CCHAR, false },
+ },
+ { ERR(NULL_POINTER) });
+ if (error != ERR(NONE)) {
+ return error;
+ }
+
// Copy into output buffer.
*extension_count_ptr = ext_vector.size();
diff --git a/tools/dump-jvmti-state/Android.bp b/tools/dump-jvmti-state/Android.bp
new file mode 100644
index 0000000..5c78965
--- /dev/null
+++ b/tools/dump-jvmti-state/Android.bp
@@ -0,0 +1,56 @@
+//
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// Build variants {target,host} x {debug,ndebug} x {32,64}
+cc_defaults {
+ name: "dumpjvmti-defaults",
+ host_supported: true,
+ srcs: ["dump-jvmti.cc"],
+ defaults: ["art_defaults"],
+
+ // Note that this tool needs to be built for both 32-bit and 64-bit since it requires
+ // to be same ISA as what it is attached to.
+ compile_multilib: "both",
+
+ shared_libs: [
+ "libbase",
+ ],
+ header_libs: [
+ "libopenjdkjvmti_headers",
+ ],
+ multilib: {
+ lib32: {
+ suffix: "32",
+ },
+ lib64: {
+ suffix: "64",
+ },
+ },
+ symlink_preferred_arch: true,
+}
+
+art_cc_library {
+ name: "libdumpjvmti",
+ defaults: ["dumpjvmti-defaults"],
+}
+
+art_cc_library {
+ name: "libdumpjvmtid",
+ defaults: [
+ "art_debug_defaults",
+ "dumpjvmti-defaults",
+ ],
+}
diff --git a/tools/dump-jvmti-state/README.md b/tools/dump-jvmti-state/README.md
new file mode 100644
index 0000000..4aabc08
--- /dev/null
+++ b/tools/dump-jvmti-state/README.md
@@ -0,0 +1,27 @@
+# dumpjvmti
+
+dumpjvmti is a JVMTI agent designed for helping debug the working of the openjdkjvmti plugin. It
+allows one to use SIGQUIT to dump information about the current JVMTI state to logcat. It does
+this by calling the com.android.art.misc.get_plugin_internal_state extension function.
+
+# Usage
+### Build
+> `make libdumpjvmti`
+
+The libraries will be built for 32-bit, 64-bit, host and target. Below examples
+assume you want to use the 64-bit version.
+
+#### ART
+> `art -Xplugin:$ANDROID_HOST_OUT/lib64/libopenjdkjvmti.so '-agentpath:libdumpjvmti.so' -cp tmp/java/helloworld.dex -Xint helloworld`
+> `kill -3 <pid>`
+
+* `-Xplugin` and `-agentpath` need to be used, otherwise the agent will fail during init.
+* If using `libartd.so`, make sure to use the debug version of jvmti.
+
+> `adb shell setenforce 0`
+>
+> `adb push $ANDROID_PRODUCT_OUT/system/lib64/libdumpjvmti.so /data/local/tmp/`
+>
+> `adb shell am start-activity --attach-agent /data/local/tmp/libdumpjvmti.so some.debuggable.apps/.the.app.MainActivity`
+>
+> `adb shell kill -3 $(adb shell pidof some.debuggable.apps)`
\ No newline at end of file
diff --git a/tools/dump-jvmti-state/dump-jvmti.cc b/tools/dump-jvmti-state/dump-jvmti.cc
new file mode 100644
index 0000000..71a0115
--- /dev/null
+++ b/tools/dump-jvmti-state/dump-jvmti.cc
@@ -0,0 +1,115 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include <android-base/logging.h>
+
+#include <jni.h>
+#include <jvmti.h>
+
+namespace dumpjvmti {
+
+namespace {
+
+// Special art ti-version number. We will use this as a fallback if we cannot get a regular JVMTI
+// env.
+static constexpr jint kArtTiVersion = JVMTI_VERSION_1_2 | 0x40000000;
+
+template <typename T> static void Dealloc(jvmtiEnv* env, T* t) {
+ env->Deallocate(reinterpret_cast<unsigned char*>(t));
+}
+
+template <typename T, typename... Rest> static void Dealloc(jvmtiEnv* env, T* t, Rest... rs) {
+ Dealloc(env, t);
+ Dealloc(env, rs...);
+}
+
+static void DeallocParams(jvmtiEnv* env, jvmtiParamInfo* params, jint n_params) {
+ for (jint i = 0; i < n_params; i++) {
+ Dealloc(env, params[i].name);
+ }
+}
+
+// The extension function to get the internal data
+static jvmtiError (*GetInternalData)(jvmtiEnv* env, unsigned char** data) = nullptr;
+
+static jint SetupJvmtiEnv(JavaVM* vm, jvmtiEnv** jvmti) {
+ jint res = 0;
+ res = vm->GetEnv(reinterpret_cast<void**>(jvmti), JVMTI_VERSION_1_1);
+
+ if (res != JNI_OK || *jvmti == nullptr) {
+ LOG(ERROR) << "Unable to access JVMTI, error code " << res;
+ res = vm->GetEnv(reinterpret_cast<void**>(jvmti), kArtTiVersion);
+ if (res != JNI_OK) {
+ return res;
+ }
+ }
+
+ jvmtiEnv* env = *jvmti;
+
+ // Get the extensions.
+ jint n_ext = 0;
+ jvmtiExtensionFunctionInfo* infos = nullptr;
+ if (env->GetExtensionFunctions(&n_ext, &infos) != JVMTI_ERROR_NONE) {
+ return JNI_ERR;
+ }
+ for (jint i = 0; i < n_ext; i++) {
+ jvmtiExtensionFunctionInfo* cur_info = &infos[i];
+ if (strcmp("com.android.art.misc.get_plugin_internal_state", cur_info->id) == 0) {
+ GetInternalData = reinterpret_cast<decltype(GetInternalData)>(cur_info->func);
+ }
+ // Cleanup the cur_info
+ DeallocParams(env, cur_info->params, cur_info->param_count);
+ Dealloc(env, cur_info->id, cur_info->short_description, cur_info->params, cur_info->errors);
+ }
+ // Cleanup the array.
+ Dealloc(env, infos);
+ return GetInternalData != nullptr ? JNI_OK : JNI_ERR;
+}
+
+static void CbDataDump(jvmtiEnv* jvmti) {
+ unsigned char* data = nullptr;
+ if (JVMTI_ERROR_NONE == GetInternalData(jvmti, &data)) {
+ LOG(INFO) << data;
+ Dealloc(jvmti, data);
+ }
+}
+
+} // namespace
+
+static jint AgentStart(JavaVM* vm, char* options ATTRIBUTE_UNUSED, void* reserved ATTRIBUTE_UNUSED) {
+ jvmtiEnv* jvmti = nullptr;
+ if (SetupJvmtiEnv(vm, &jvmti) != JNI_OK) {
+ LOG(ERROR) << "Could not get JVMTI env or ArtTiEnv!";
+ return JNI_ERR;
+ }
+ jvmtiEventCallbacks cb{
+ .DataDumpRequest = CbDataDump,
+ };
+ jvmti->SetEventCallbacks(&cb, sizeof(cb));
+ jvmti->SetEventNotificationMode(JVMTI_ENABLE, JVMTI_EVENT_DATA_DUMP_REQUEST, nullptr);
+ return JNI_OK;
+}
+
+// Late attachment (e.g. 'am attach-agent').
+extern "C" JNIEXPORT jint JNICALL Agent_OnAttach(JavaVM* vm, char* options, void* reserved) {
+ return AgentStart(vm, options, reserved);
+}
+
+// Early attachment
+extern "C" JNIEXPORT jint JNICALL Agent_OnLoad(JavaVM* jvm, char* options, void* reserved) {
+ return AgentStart(jvm, options, reserved);
+}
+
+} // namespace dumpjvmti
