From f9eb97fdff9517d7b7f0f1ddec936dd3920ce89c Mon Sep 17 00:00:00 2001 From: Martin Kustermann Date: Thu, 13 Apr 2023 09:20:17 +0000 Subject: [PATCH] Reland "[vm] Expose Dart_{CurrentIsolate,ExitIsolate,EnterIsolate}" For applications that want to have arbitrary number of isolates call into native code that may be blocking, we expose the API functions that allows those native threads to exit an isolate before running long/blocking code. Without the ability to exit/re-enter isolate, one may experience deadlocks as we have a fixed limit on the number of concurrently executing isolates atm. In the longer term we may find a way to do this automatically with low overhead, see [0]. But since those API functions are quite stable and we already expose e.g. `Dart_{Enter,Exit}Scope`, I don't see a reason not to expose `Dart_{Enter,Exit}Isolate`. Difference to original CL: Do use STL synchronization primitives (as the ones in runtime/bin are not always available in shared libraries) [0] Issue https://github.com/dart-lang/sdk/issues/51261 Issue https://github.com/dart-lang/sdk/issues/51254 TEST=ffi{,_2}/dl_api_exit_enter_isolate_test Change-Id: Id817e8d4edb3db35f029248d62388cbd0682001d Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/294980 Reviewed-by: Daco Harkes --- .../ffi_test/ffi_test_functions_vmspecific.cc | 16 ++++----- runtime/include/dart_api_dl.h | 4 +++ runtime/include/dart_version.h | 2 +- tests/ffi/dl_api_exit_enter_isolate_test.dart | 33 +++++++++++++++++ .../ffi_2/dl_api_exit_enter_isolate_test.dart | 35 +++++++++++++++++++ 5 files changed, 81 insertions(+), 9 deletions(-) create mode 100644 tests/ffi/dl_api_exit_enter_isolate_test.dart create mode 100644 tests/ffi_2/dl_api_exit_enter_isolate_test.dart diff --git a/runtime/bin/ffi_test/ffi_test_functions_vmspecific.cc b/runtime/bin/ffi_test/ffi_test_functions_vmspecific.cc index 9ecaa7ec688..77ab3511f53 100644 --- a/runtime/bin/ffi_test/ffi_test_functions_vmspecific.cc +++ b/runtime/bin/ffi_test/ffi_test_functions_vmspecific.cc @@ -894,16 +894,11 @@ DART_EXPORT void ThreadPoolTest_BarrierSync( dart_exit_isolate(); { std::unique_lock lock(mutex); - ++thread_count; - if (thread_count < num_threads) { - while (thread_count < num_threads) { - cvar.wait(lock); - } - } else { - if (thread_count != num_threads) FATAL("bug"); - cvar.notify_all(); + while (thread_count < num_threads) { + cvar.wait(lock); } + cvar.notify_all(); } dart_enter_isolate(isolate); } @@ -1282,6 +1277,11 @@ DART_EXPORT void SetFfiNativeResolverForTest(Dart_Handle url) { ENSURE(!Dart_IsError(result)); } +DART_EXPORT void WaitUntilNThreadsEnterBarrier(intptr_t num_threads) { + ThreadPoolTest_BarrierSync(Dart_CurrentIsolate_DL, Dart_EnterIsolate_DL, + Dart_ExitIsolate_DL, num_threads); +} + //////////////////////////////////////////////////////////////////////////////// // Helper for the regression test for b/216834909 //////////////////////////////////////////////////////////////////////////////// diff --git a/runtime/include/dart_api_dl.h b/runtime/include/dart_api_dl.h index ba50d992369..cce34500947 100644 --- a/runtime/include/dart_api_dl.h +++ b/runtime/include/dart_api_dl.h @@ -90,6 +90,10 @@ typedef void (*Dart_NativeMessageHandler_DL)(Dart_Port_DL dest_port_id, F(Dart_UpdateFinalizableExternalSize, void, \ (Dart_FinalizableHandle object, Dart_Handle strong_ref_to_object, \ intptr_t external_allocation_size)) \ + /* Isolates */ \ + F(Dart_CurrentIsolate, Dart_Isolate, (void)) \ + F(Dart_ExitIsolate, void, (void)) \ + F(Dart_EnterIsolate, void, (Dart_Isolate)) \ /* Dart_Port */ \ F(Dart_Post, bool, (Dart_Port_DL port_id, Dart_Handle object)) \ F(Dart_NewSendPort, Dart_Handle, (Dart_Port_DL port_id)) \ diff --git a/runtime/include/dart_version.h b/runtime/include/dart_version.h index 680fb539bbe..e2d3651fbd3 100644 --- a/runtime/include/dart_version.h +++ b/runtime/include/dart_version.h @@ -11,6 +11,6 @@ // On backwards compatible changes the minor version is increased. // The versioning covers the symbols exposed in dart_api_dl.h #define DART_API_DL_MAJOR_VERSION 2 -#define DART_API_DL_MINOR_VERSION 2 +#define DART_API_DL_MINOR_VERSION 3 #endif /* RUNTIME_INCLUDE_DART_VERSION_H_ */ /* NOLINT */ diff --git a/tests/ffi/dl_api_exit_enter_isolate_test.dart b/tests/ffi/dl_api_exit_enter_isolate_test.dart new file mode 100644 index 00000000000..5842cc8ba72 --- /dev/null +++ b/tests/ffi/dl_api_exit_enter_isolate_test.dart @@ -0,0 +1,33 @@ +// Copyright (c) 2023, the Dart project authors. Please see the AUTHORS file +// for details. All rights reserved. Use of this source code is governed by a +// BSD-style license that can be found in the LICENSE file. + +// SharedObjects=ffi_test_functions + +import 'dart:ffi'; +import 'dart:isolate'; + +import 'package:expect/expect.dart'; + +import 'dylib_utils.dart'; + +final ffiTestFunctions = dlopenPlatformSpecific("ffi_test_functions"); + +final initializeApi = ffiTestFunctions.lookupFunction< + IntPtr Function(Pointer), + int Function(Pointer)>("InitDartApiDL"); +final enterBarrier = + ffiTestFunctions.lookupFunction( + "WaitUntilNThreadsEnterBarrier"); + +main() async { + const threadBarrierCount = 30; + + initializeApi(NativeApi.initializeApiDLData); + + final all = []; + for (int i = 0; i < threadBarrierCount; ++i) { + all.add(Isolate.run(() => enterBarrier(threadBarrierCount))); + } + await Future.wait(all); +} diff --git a/tests/ffi_2/dl_api_exit_enter_isolate_test.dart b/tests/ffi_2/dl_api_exit_enter_isolate_test.dart new file mode 100644 index 00000000000..03abbb3ed50 --- /dev/null +++ b/tests/ffi_2/dl_api_exit_enter_isolate_test.dart @@ -0,0 +1,35 @@ +// Copyright (c) 2023, the Dart project authors. Please see the AUTHORS file +// for details. All rights reserved. Use of this source code is governed by a +// BSD-style license that can be found in the LICENSE file. + +// @dart = 2.9 + +// SharedObjects=ffi_test_functions + +import 'dart:ffi'; +import 'dart:isolate'; + +import 'package:expect/expect.dart'; + +import 'dylib_utils.dart'; + +final ffiTestFunctions = dlopenPlatformSpecific("ffi_test_functions"); + +final initializeApi = ffiTestFunctions.lookupFunction< + IntPtr Function(Pointer), + int Function(Pointer)>("InitDartApiDL"); +final enterBarrier = + ffiTestFunctions.lookupFunction( + "WaitUntilNThreadsEnterBarrier"); + +main() async { + const threadBarrierCount = 30; + + initializeApi(NativeApi.initializeApiDLData); + + final all = []; + for (int i = 0; i < threadBarrierCount; ++i) { + all.add(Isolate.run(() => enterBarrier(threadBarrierCount))); + } + await Future.wait(all); +}