This CL implements `NativeFinalizer` in the GC.
`FinalizerEntry`s are extended to track `external_size` and in which
`Heap::Space` the finalizable value is.
On attaching a native finalizer, the external size is added to the
relevant heap. When the finalizable value is promoted from new to old
space, the external size is promoted as well. And when a native
finalizer is run or is detached, the external size is removed from the
relevant heap again.
In contrast to Dart `Finalizer`s, `NativeFinalizer`s are run on isolate
shutdown.
When the `NativeFinalizer`s themselves are collected, the finalizers are
not run. Users should stick the native finalizer in a global variable to
ensure finalization. We will revisit this design when we add send and
exit support, because there is a design space to explore what to do in
that case. This current solution promises the least to users.
In this implementation native finalizers have a Dart entry to clean up
the entries from the `all_entries` field of the finalizer. We should
consider using another data structure that avoids the need for this Dart
entry. See the TODO left in the code.
Bug: https://github.com/dart-lang/sdk/issues/47777
TEST=runtime/tests/vm/dart(_2)/isolates/fast_object_copy_test.dart
TEST=runtime/vm/object_test.cc
TEST=tests/ffi(_2)/vmspecific_native_finalizer_*
Change-Id: I8f594c80c3c344ad83e1f2de10de028eb8456121
Cq-Include-Trybots: luci.dart.try:vm-kernel-reload-rollback-linux-debug-x64-try,vm-kernel-reload-linux-debug-x64-try,vm-ffi-android-debug-arm64c-try,dart-sdk-mac-arm64-try,vm-kernel-mac-release-arm64-try,pkg-mac-release-arm64-try,vm-kernel-precomp-nnbd-mac-release-arm64-try,vm-kernel-win-debug-x64c-try,vm-kernel-win-debug-x64-try,vm-kernel-precomp-win-debug-x64c-try,vm-kernel-nnbd-win-release-ia32-try,vm-ffi-android-debug-arm-try,vm-precomp-ffi-qemu-linux-release-arm-try,vm-kernel-mac-debug-x64-try,vm-kernel-nnbd-mac-debug-x64-try,vm-kernel-nnbd-linux-debug-ia32-try,benchmark-linux-try,flutter-frontend-try,pkg-linux-debug-try,vm-kernel-asan-linux-release-x64-try,vm-kernel-gcc-linux-try,vm-kernel-optcounter-threshold-linux-release-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-obfuscate-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/236320
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Original CL in patchset 1.
Split-off https://dart-review.googlesource.com/c/sdk/+/238341
And pulled in fix https://dart-review.googlesource.com/c/sdk/+/238582
(Should merge cleanly when this lands later.)
This CL implements the `Finalizer` in the GC.
The GC is specially aware of two types of objects for the purposes of
running finalizers.
1) `FinalizerEntry`
2) `Finalizer` (`FinalizerBase`, `_FinalizerImpl`)
A `FinalizerEntry` contains the `value`, the optional `detach` key, and
the `token`, and a reference to the `finalizer`.
An entry only holds on weakly to the value, detach key, and finalizer.
(Similar to how `WeakReference` only holds on weakly to target).
A `Finalizer` contains all entries, a list of entries of which the value
is collected, and a reference to the isolate.
When a the value of an entry is GCed, the enry is added over to the
collected list.
If any entry is moved to the collected list, a message is sent that
invokes the finalizer to call the callback on all entries in that list.
When a finalizer is detached by the user, the entry token is set to the
entry itself and is removed from the all entries set.
This ensures that if the entry was already moved to the collected list,
the finalizer is not executed.
To speed up detaching, we use a weak map from detach keys to list of
entries. This ensures entries can be GCed.
Both the scavenger and marker tasks process finalizer entries in
parallel.
Parallel tasks use an atomic exchange on the head of the collected
entries list, ensuring no entries get lost.
The mutator thread is guaranteed to be stopped when processing entries.
This ensures that we do not need barriers for moving entries into the
finalizers collected list.
Dart reads and replaces the collected entries list also with an atomic
exchange, ensuring the GC doesn't run in between a load/store.
When a finalizer gets posted a message to process finalized objects, it
is being kept alive by the message.
An alternative design would be to pre-allocate a `WeakReference` in the
finalizer pointing to the finalizer, and send that itself.
This would be at the cost of an extra object.
Send and exit is not supported in this CL, support will be added in a
follow up CL. Trying to send will throw.
Bug: https://github.com/dart-lang/sdk/issues/47777
TEST=runtime/tests/vm/dart/finalizer/*
TEST=runtime/tests/vm/dart_2/isolates/fast_object_copy_test.dart
TEST=runtime/vm/object_test.cc
Change-Id: Ibdfeadc16d5d69ade50aae5b9f794284c4c4dbab
Cq-Include-Trybots: luci.dart.try:vm-kernel-reload-rollback-linux-debug-x64-try,vm-kernel-reload-linux-debug-x64-try,vm-ffi-android-debug-arm64c-try,dart-sdk-mac-arm64-try,vm-kernel-mac-release-arm64-try,pkg-mac-release-arm64-try,vm-kernel-precomp-nnbd-mac-release-arm64-try,vm-kernel-win-debug-x64c-try,vm-kernel-win-debug-x64-try,vm-kernel-precomp-win-debug-x64c-try,vm-kernel-nnbd-win-release-ia32-try,vm-ffi-android-debug-arm-try,vm-precomp-ffi-qemu-linux-release-arm-try,vm-kernel-mac-debug-x64-try,vm-kernel-nnbd-mac-debug-x64-try,vm-kernel-nnbd-linux-debug-ia32-try,benchmark-linux-try,flutter-analyze-try,flutter-frontend-try,pkg-linux-debug-try,vm-kernel-asan-linux-release-x64-try,vm-kernel-gcc-linux-try,vm-kernel-optcounter-threshold-linux-release-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-obfuscate-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/238086
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
This reverts commit 7dca34c235.
Reason for revert: b/226085355 dart_vm_test crashing. Unclear what
the cause is. Reverting so we can triage the issue.
TEST=This is a revert.
Original change's description:
> [vm] Implement `Finalizer`
>
> This CL implements the `Finalizer` in the GC.
>
> (This CL does not yet implement `NativeFinalizer`.)
>
> The GC is specially aware of two types of objects for the purposes of
> running finalizers.
>
> 1) `FinalizerEntry`
> 2) `Finalizer` (`FinalizerBase`, `_FinalizerImpl`)
>
> A `FinalizerEntry` contains the `value`, the optional `detach` key, and
> the `token`, and a reference to the `finalizer`.
> An entry only holds on weakly to the value, detach key, and finalizer.
> (Similar to how `WeakReference` only holds on weakly to target).
>
> A `Finalizer` contains all entries, a list of entries of which the value
> is collected, and a reference to the isolate.
>
> When a the value of an entry is GCed, the enry is added over to the
> collected list.
> If any entry is moved to the collected list, a message is sent that
> invokes the finalizer to call the callback on all entries in that list.
>
> When a finalizer is detached by the user, the entry token is set to the
> entry itself and is removed from the all entries set.
> This ensures that if the entry was already moved to the collected list,
> the finalizer is not executed.
>
> To speed up detaching, we use a weak map from detach keys to list of
> entries. This ensures entries can be GCed.
>
> Both the scavenger and marker tasks process finalizer entries in
> parallel.
> Parallel tasks use an atomic exchange on the head of the collected
> entries list, ensuring no entries get lost.
> The mutator thread is guaranteed to be stopped when processing entries.
> This ensures that we do not need barriers for moving entries into the
> finalizers collected list.
> Dart reads and replaces the collected entries list also with an atomic
> exchange, ensuring the GC doesn't run in between a load/store.
>
> When a finalizer gets posted a message to process finalized objects, it
> is being kept alive by the message.
> An alternative design would be to pre-allocate a `WeakReference` in the
> finalizer pointing to the finalizer, and send that itself.
> This would be at the cost of an extra object.
>
> Send and exit is not supported in this CL, support will be added in a
> follow up CL. Trying to send will throw.
>
> Bug: https://github.com/dart-lang/sdk/issues/47777
>
> TEST=runtime/tests/vm/dart/finalizer/*
> TEST=runtime/tests/vm/dart_2/isolates/fast_object_copy_test.dart
> TEST=runtime/vm/object_test.cc
>
> Change-Id: I03e6b4a46212316254bf46ba3f2df333abaa686c
> Cq-Include-Trybots: luci.dart.try:vm-kernel-reload-rollback-linux-debug-x64-try,vm-kernel-reload-linux-debug-x64-try,vm-ffi-android-debug-arm64c-try,dart-sdk-mac-arm64-try,vm-kernel-mac-release-arm64-try,pkg-mac-release-arm64-try,vm-kernel-precomp-nnbd-mac-release-arm64-try,vm-kernel-win-debug-x64c-try,vm-kernel-win-debug-x64-try,vm-kernel-precomp-win-debug-x64c-try,vm-kernel-nnbd-win-release-ia32-try,vm-ffi-android-debug-arm-try,vm-precomp-ffi-qemu-linux-release-arm-try,vm-kernel-mac-debug-x64-try,vm-kernel-nnbd-mac-debug-x64-try,vm-kernel-nnbd-linux-debug-ia32-try,benchmark-linux-try,flutter-analyze-try,flutter-frontend-try,pkg-linux-debug-try,vm-kernel-asan-linux-release-x64-try,vm-kernel-gcc-linux-try,vm-kernel-optcounter-threshold-linux-release-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-obfuscate-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/229544
> Reviewed-by: Lasse Nielsen <lrn@google.com>
> Reviewed-by: Slava Egorov <vegorov@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>
> Reviewed-by: Ryan Macnak <rmacnak@google.com>
> Commit-Queue: Daco Harkes <dacoharkes@google.com>
TBR=lrn@google.com,vegorov@google.com,kustermann@google.com,rmacnak@google.com,dacoharkes@google.com
Change-Id: I991f6e49896d18a8d70210cf315d858b462d66c9
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: https://github.com/dart-lang/sdk/issues/47777
Cq-Include-Trybots: luci.dart.try:vm-kernel-reload-rollback-linux-debug-x64-try,vm-kernel-reload-linux-debug-x64-try,vm-ffi-android-debug-arm64c-try,dart-sdk-mac-arm64-try,vm-kernel-mac-release-arm64-try,pkg-mac-release-arm64-try,vm-kernel-precomp-nnbd-mac-release-arm64-try,vm-kernel-win-debug-x64c-try,vm-kernel-win-debug-x64-try,vm-kernel-precomp-win-debug-x64c-try,vm-kernel-nnbd-win-release-ia32-try,vm-ffi-android-debug-arm-try,vm-precomp-ffi-qemu-linux-release-arm-try,vm-kernel-mac-debug-x64-try,vm-kernel-nnbd-mac-debug-x64-try,vm-kernel-nnbd-linux-debug-ia32-try,benchmark-linux-try,flutter-analyze-try,flutter-frontend-try,pkg-linux-debug-try,vm-kernel-asan-linux-release-x64-try,vm-kernel-gcc-linux-try,vm-kernel-optcounter-threshold-linux-release-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-obfuscate-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/238080
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
This CL implements the `Finalizer` in the GC.
(This CL does not yet implement `NativeFinalizer`.)
The GC is specially aware of two types of objects for the purposes of
running finalizers.
1) `FinalizerEntry`
2) `Finalizer` (`FinalizerBase`, `_FinalizerImpl`)
A `FinalizerEntry` contains the `value`, the optional `detach` key, and
the `token`, and a reference to the `finalizer`.
An entry only holds on weakly to the value, detach key, and finalizer.
(Similar to how `WeakReference` only holds on weakly to target).
A `Finalizer` contains all entries, a list of entries of which the value
is collected, and a reference to the isolate.
When a the value of an entry is GCed, the enry is added over to the
collected list.
If any entry is moved to the collected list, a message is sent that
invokes the finalizer to call the callback on all entries in that list.
When a finalizer is detached by the user, the entry token is set to the
entry itself and is removed from the all entries set.
This ensures that if the entry was already moved to the collected list,
the finalizer is not executed.
To speed up detaching, we use a weak map from detach keys to list of
entries. This ensures entries can be GCed.
Both the scavenger and marker tasks process finalizer entries in
parallel.
Parallel tasks use an atomic exchange on the head of the collected
entries list, ensuring no entries get lost.
The mutator thread is guaranteed to be stopped when processing entries.
This ensures that we do not need barriers for moving entries into the
finalizers collected list.
Dart reads and replaces the collected entries list also with an atomic
exchange, ensuring the GC doesn't run in between a load/store.
When a finalizer gets posted a message to process finalized objects, it
is being kept alive by the message.
An alternative design would be to pre-allocate a `WeakReference` in the
finalizer pointing to the finalizer, and send that itself.
This would be at the cost of an extra object.
Send and exit is not supported in this CL, support will be added in a
follow up CL. Trying to send will throw.
Bug: https://github.com/dart-lang/sdk/issues/47777
TEST=runtime/tests/vm/dart/finalizer/*
TEST=runtime/tests/vm/dart_2/isolates/fast_object_copy_test.dart
TEST=runtime/vm/object_test.cc
Change-Id: I03e6b4a46212316254bf46ba3f2df333abaa686c
Cq-Include-Trybots: luci.dart.try:vm-kernel-reload-rollback-linux-debug-x64-try,vm-kernel-reload-linux-debug-x64-try,vm-ffi-android-debug-arm64c-try,dart-sdk-mac-arm64-try,vm-kernel-mac-release-arm64-try,pkg-mac-release-arm64-try,vm-kernel-precomp-nnbd-mac-release-arm64-try,vm-kernel-win-debug-x64c-try,vm-kernel-win-debug-x64-try,vm-kernel-precomp-win-debug-x64c-try,vm-kernel-nnbd-win-release-ia32-try,vm-ffi-android-debug-arm-try,vm-precomp-ffi-qemu-linux-release-arm-try,vm-kernel-mac-debug-x64-try,vm-kernel-nnbd-mac-debug-x64-try,vm-kernel-nnbd-linux-debug-ia32-try,benchmark-linux-try,flutter-analyze-try,flutter-frontend-try,pkg-linux-debug-try,vm-kernel-asan-linux-release-x64-try,vm-kernel-gcc-linux-try,vm-kernel-optcounter-threshold-linux-release-x64-try,vm-kernel-precomp-linux-debug-simarm_x64-try,vm-kernel-precomp-obfuscate-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/229544
Reviewed-by: Lasse Nielsen <lrn@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
This reverts commit f8df8ca78e.
Reason for revert: breaks google3 (b/205519688)
Original change's description:
> [vm/concurrency] Remove --(no-)enable-isolate-groups flag in Dart VM
>
> The --enable-isolate-groups flag has been turned on by-default for
> months now. In this CL we're going to remove the opt-out of this (which
> was possible by explicitly passing --no-enable-isolate-groups to the VM)
>
> TEST=Existing CI. Removes flag and simplifies runtime.
>
> Change-Id: I8706b9e30df437548a81846e75e67a658d6d49d4
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/219480
> Reviewed-by: Alexander Aprelev <aam@google.com>
> Commit-Queue: Martin Kustermann <kustermann@google.com>
# Not skipping CQ checks because original CL landed > 1 day ago.
Change-Id: Iabe6ccda6c184bb183b54a056d5011e657265d1d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/219700
Reviewed-by: Emmanuel Pellereau <emmanuelp@google.com>
Reviewed-by: Aske Simon Christensen <askesc@google.com>
Commit-Queue: Emmanuel Pellereau <emmanuelp@google.com>
The --enable-isolate-groups flag has been turned on by-default for
months now. In this CL we're going to remove the opt-out of this (which
was possible by explicitly passing --no-enable-isolate-groups to the VM)
TEST=Existing CI. Removes flag and simplifies runtime.
Change-Id: I8706b9e30df437548a81846e75e67a658d6d49d4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/219480
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
The existing lib/isolate/stacktrace_message_test was failing and also
incorrectly written due to "!" in front of the expected stringification
of the stacktrace.
Issue https://github.com/dart-lang/sdk/issues/46623
TEST=vm/dart{,_2}/isolates/fast_object_copy2_test, lib{,_2}/isolate/stacktrace_message_test
Change-Id: I169d8fd7a7c3cb3b8c57e00287565e3a5c622acf
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/216041
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
We already allow sending closures (if immutable via sharing
otherwise via copying). This CL makes use of this to allow the argument
to `Isolate.spawn()` to be any closure.
Similar to normal message sending, the spawn will fail if the closure
cannot be sent (or causes an error on the new isolate, e.g. rehashing
error).
Issue https://github.com/dart-lang/sdk/issues/46623
TEST=vm/dart{_2,}/isolates/closure_entrypoint_test
Change-Id: Iab342267d87bd87bc8c0c82d16aec58a69a3df44
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212295
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
The destructor of [IsolateSpawnState] might call destructors on
[Message] which may want to delete persistent handles. Doing so requires
an active isolate group.
This CL ensure that in shutdown races (main isolate exists which
triggers VM shutdown, helper islate is about to start but fails to start
due to VM shutdown request), we still ensure to properly delete the
persistent handles.
TEST=Fixes vm/dart_2/spawn_shutdown_test/0 on app-jit configurations.
Change-Id: I0c3e0ceca7faab36f298953dabb1ccae3a0ecc8a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212464
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
This particular test was not run in both modes (--enable-isolate-groups
and --no-enable-isolate-groups). So enabling the flag made this test
fail.
It fails because it shutdown the isolate before destroying the
[IsolateSpawnState] - which in return destroys persistant handles which
needs the isolate to be still alive.
TEST=Fixes vm/dart{,_2}/spawn_shutdown_test
Change-Id: Ib06e1149c4066fa993e899bbd3bfdba8a2533b48
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212292
Auto-Submit: Martin Kustermann <kustermann@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
Commit-Queue: Alexander Aprelev <aam@google.com>
This was mainly used as a backup plan which is no longer needed at this
point.
This CL removes internal only functionality that couldn't be used by
end-users.
TEST=ci
Change-Id: Ie0828bda1ba48ee6a5a460ff039267e0549e0060
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/210340
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Add missing checks for FFI types disallowed in isolate messages.
Align error messages with the other serializer and test expectations.
TEST=ci
Change-Id: I3813dd8f26e5122524bdf41f9ce6e0785fdd260b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/209840
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
The transitive copy algorithm was missing support for [WeakProperty]s,
thereby ensuring that we only copy the values if the keys are reachable.
Furthermore we might need to re-hash [Expando]s - since the copied
objects start with no identity hash codes.
The CL also makes us avoid calling to Dart for each [Expando]
separately and instead use a list - just as we do in the re-hashing of
maps/sets.
We also move the C++ code to invoke rehashing logic into
DartLibraryCalls::*.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=vm/dart{,_2}/isolates/fast_object_copy{,2}_test
Change-Id: I836745feef8a6d7573faa94e29a19c1eca0c39f2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/209106
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Allows for tools like the Dart test runner to hide the main isolate by
marking it as a system isolate, only showing the isolates users are
interested in.
TEST=pkg/vm_service/mark_main_isolate_as_system_isolate_test.dart
Change-Id: I24d0f20614e89076a05499c206d576c355489a13
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/207203
Reviewed-by: Jacob Richman <jacobr@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>
We use message passing as comunication mechanism between isolates.
The transitive closure of an object to be sent is currently serialized
into a snapshot form and deserialized on the receiver side. Furthermore
the receiver side will re-hash any linked hashmaps in that graph.
If isolate gropus are enabled we have all isolates in a group work on
the same heap. That removes the need to use an intermediate
serialization format. It also removes the need for an O(n) step on the
receiver side.
This CL implements a fast transitive object copy implementation and
makes use of it a message that is to be passed to another isolate stays
within the same isolate group.
In the common case the object graph will fit into new space. So the
copy algorithm will try to take advantage of it by having a fast path
and a fallback path. Both of them effectively copy the graph in BFS
order.
The algorithm works effectively like a scavenge operation, but instead
of first copying the from-object to the to-space and then re-writing the
object in to-space to forward the pointers (which requires us writing to
the to-space memory twice), we only reserve space for to-objects and
then initialize the to-objects to it's final contents, including
forwarded pointers (i.e. write the to-space object only once).
Compared with a scavenge operation (which stores forwarding pointers in
the objects themselves), we use a [WeakTable] to store them. This is the
only remaining expensive part of the algorithm and could be further
optimized. To avoid relying on iterating the to-space, we'll remember
[from, to] addresses.
=> All of this works inside a [NoSafepointOperationScope] and avoids
usages of handles as well as write barriers.
While doing the transitive object copy, we'll share any object we can
safely share (canonical objects, strings, sendports, ...) instead of
copying it.
If the fast path fails (due to allocation failure or hitting) we'll
handlify any raw pointers and continue almost the same algorithm in a
safe way, where GC is possible at every object allocation site and
normal barriers are used for any stores of object pointers.
The copy algorithm uses templates to share the copy logic between the
fast and slow case (same copy routines can work on raw pointers as well
as handles).
There's a few special things to take into consideration:
* If we copy a view on external typed data we need to know the
external typed data address to compute the inner pointer of the
view, so we'll eagerly initialize external typed data.
* All external typed data needs to get a finalizer attached
(irrespective if the object copy suceeds or not) to ensure the
`malloc()`ed data is freed again.
* Transferables will only be transferred on successful transitive
copies. Also they need to attach finalizers to objects (which
requires all objects be in handles).
* We copy linked hashmaps as they are - instead of compressing the
data by removing deleted entries. We may need to re-hash those
hashmaps on the receiver side (similar to the snapshot-based copy
approach) since new object graph will have no identity hash codes
assigned to them. Though if the hashmaps only has sharable objects
as keys (very common, e.g. json) there is no need for re-hashing.
It changes the SendPort.* benchmarks as follows:
```
Benchmark | default | IG | IG + FOC
----------------------------------------------------------------------------------------------------------------------------
SendPort.Send.Nop(RunTimeRaw): | 0.25 us (1 x) | 0.26 us (0.96 x) | 0.25 us (1.00 x)
SendPort.Send.Json.400B(RunTimeRaw): | 4.15 us (1 x) | 1.45 us (2.86 x) | 1.05 us (3.95 x)
SendPort.Send.Json.5KB(RunTimeRaw): | 82.16 us (1 x) | 27.17 us (3.02 x) | 18.32 us (4.48 x)
SendPort.Send.Json.50KB(RunTimeRaw): | 784.70 us (1 x) | 242.10 us (3.24 x) | 165.50 us (4.74 x)
SendPort.Send.Json.500KB(RunTimeRaw): | 8510.4 us (1 x) | 3083.80 us (2.76 x) | 2311.29 us (3.68 x)
SendPort.Send.Json.5MB(RunTimeRaw): | 122381.33 us (1 x) | 62959.40 us (1.94 x) | 55492.10 us (2.21 x)
SendPort.Send.BinaryTree.2(RunTimeRaw): | 1.91 us (1 x) | 0.92 us (2.08 x) | 0.72 us (2.65 x)
SendPort.Send.BinaryTree.4(RunTimeRaw): | 6.32 us (1 x) | 2.70 us (2.34 x) | 2.10 us (3.01 x)
SendPort.Send.BinaryTree.6(RunTimeRaw): | 25.24 us (1 x) | 10.47 us (2.41 x) | 8.61 us (2.93 x)
SendPort.Send.BinaryTree.8(RunTimeRaw): | 104.08 us (1 x) | 41.08 us (2.53 x) | 33.51 us (3.11 x)
SendPort.Send.BinaryTree.10(RunTimeRaw): | 373.39 us (1 x) | 174.11 us (2.14 x) | 134.75 us (2.77 x)
SendPort.Send.BinaryTree.12(RunTimeRaw): | 1588.64 us (1 x) | 893.18 us (1.78 x) | 532.05 us (2.99 x)
SendPort.Send.BinaryTree.14(RunTimeRaw): | 6849.55 us (1 x) | 3705.19 us (1.85 x) | 2507.90 us (2.73 x)
SendPort.Receive.Nop(RunTimeRaw): | 0.67 us (1 x) | 0.69 us (0.97 x) | 0.68 us (0.99 x)
SendPort.Receive.Json.400B(RunTimeRaw): | 4.37 us (1 x) | 0.78 us (5.60 x) | 0.77 us (5.68 x)
SendPort.Receive.Json.5KB(RunTimeRaw): | 45.67 us (1 x) | 0.90 us (50.74 x) | 0.87 us (52.49 x)
SendPort.Receive.Json.50KB(RunTimeRaw): | 498.81 us (1 x) | 1.24 us (402.27 x) | 1.06 us (470.58 x)
SendPort.Receive.Json.500KB(RunTimeRaw): | 5366.02 us (1 x) | 4.22 us (1271.57 x) | 4.65 us (1153.98 x)
SendPort.Receive.Json.5MB(RunTimeRaw): | 101050.88 us (1 x) | 20.81 us (4855.88 x) | 21.0 us (4811.95 x)
SendPort.Receive.BinaryTree.2(RunTimeRaw): | 3.91 us (1 x) | 0.76 us (5.14 x) | 0.74 us (5.28 x)
SendPort.Receive.BinaryTree.4(RunTimeRaw): | 9.90 us (1 x) | 0.79 us (12.53 x) | 0.76 us (13.03 x)
SendPort.Receive.BinaryTree.6(RunTimeRaw): | 33.09 us (1 x) | 0.87 us (38.03 x) | 0.84 us (39.39 x)
SendPort.Receive.BinaryTree.8(RunTimeRaw): | 126.77 us (1 x) | 0.92 us (137.79 x) | 0.88 us (144.06 x)
SendPort.Receive.BinaryTree.10(RunTimeRaw): | 533.09 us (1 x) | 0.94 us (567.12 x) | 0.92 us (579.45 x)
SendPort.Receive.BinaryTree.12(RunTimeRaw): | 2223.23 us (1 x) | 3.03 us (733.74 x) | 3.04 us (731.33 x)
SendPort.Receive.BinaryTree.14(RunTimeRaw): | 8945.66 us (1 x) | 4.03 us (2219.77 x) | 4.30 us (2080.39 x)
```
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=vm/dart{,_2}/isolates/fast_object_copy{,2}_test
Change-Id: I835c59dab573d365b8a4b9d7c5359a6ea8d8b0a7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/203776
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Storing a persistent handle in [Message] objects instead of the
[Bequest] (which is just a wrapper around a persistent handle) will
allow us to use the same mechanism for sending copies of transitive
object graphs.
Since messages can have maps inside them that need rehashing, we'll
make the persistent handle point to an array of length 2 of the format:
array = [<message>, <array-of-objects-in-message-to-rehash>]
The sendAndExit doesn't use the second part atm (since it preserves
identities and therefore avoids the need for rehashing).
Though sending transitive copies of object graphs will require this
functionality (a follow-up CL which will land with this one).
For ease of reviewing this CL was split out.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Refactoring, relying on existing test coverage.
Change-Id: I2afa78b42ef82d46477579623fd54f027136333f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/203769
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Currently external data is counted twice on the receiver size: once for
received transferable, second for newly created external typed data.
Ensure new space is collected when allocating external at the limit.
TEST=SendReceiveBytesTransferable with verbose-gc
Change-Id: I129d913f89e098b5d3066ce249ac0c4702e1394d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/199842
Commit-Queue: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
This is the initial implementation of hot reload with multi-isolate
groups.
Implementation:
As before, when a service API call triggers a reload it will be routed
as an OOB message to a specific isolate (**). As opposed to before, that
isolate has now to coordinate with all other isolates, ensuring that it
"owns" the reload and all other isolates are waiting in a state that
allows reload.
This is implemented as a [ReloadOperationScope] which first participates
in other reloads (if there are any) and then owns the reload. It will
send a new kind of service message to all other registered isolates. All
of them have to check in before reload can proceed. If a new isolate
is about to join the group, it will participate when registering the
isolate. If an old isolate wants to die, it will participate when
unregistering the isolate.
This means that in addition to the existing StackOverFlow checks that
can process OOB messages and therefore reload, we'll have isolate
registration and unregistration as well as a new
Isolate::kCheckForReload OOB message handler where an isolate can
participate in a reload.
We consider the isolate group to be reloadable if the main isolate has
loaded the program and set the root library. Helper isolates don't need
to load any more kernel code and only initialize core libraries, so it's
fine to reload them during this time.
(**) The reason we continue to send reload service API calls to any
isolate in an isolate group is that re-loading might involve calling out
to the embedder's tag handler. Doing so currently requires an active
isolate.
If we allowed a subset of dart_api.h (the subset needed by the tag
handler) to be used only with an active IsolateGroup instead of an
active Isolate we could remove this requirement.
Edge cases:
There's various edge cases to consider: The main edge case is, we currently
maintain an upper limit to the number of isolates executing in parallel
(to ensure each can have big enough chunk of new space, i.e. TLAB).
If there are more isolates with active work they are waiting until one
of the exiting ones "yields". To ensure progress, if any such actively
running isolate gets a request to participate in a reload, it will mark
its own thread as "blocked" and therefore "yields", so another isolate
can make progress until all isolates are participating and the reload
can start.
Marking an isolate as "blocked" happens by exiting that isolate. It will
free up it's TLAB, decrease active mutator count and (if running on VM's
thread pool) also temporarily increase the thread pool size.
The side-effect of this is that it will use one pthread per isolate
during reload. In the future we can extend this first implementation, by
specially handling isolates that don't have a message handler running.
Doing so would require careful consideration to avoid races.
Testing:
In order to test this we use a small helper framework for reload tests.
The helper framework will, similar to real world reload e.g. in flutter,
will spawn a subprocess. It will use the service API to trigger reloads
in this subproces.
To synchronize between the reload driver and the application being
reloaded it allows watching for events to be printed to stdout/stderr.
The reload test itself can be written - similar to multitests - with
annotations such as `// @include-in-relload-0` in them. The testing
framework will then generate multiple application versions that all get
compiled to kernel.
For simplicity we generate the kernel using the standalone VM with
`--snapshot-kind=kernel` and avoid using the incremental compiler.
There are 4 different tests exercising different aspects of
multi-isolate reload:
vm/dart_2/isolates/reload_active_stack_test:
Performs a reload while a fixed number of isolates have an active
stack, thereby ensuring e.g. that all frames of all isolate mutator
stacks get deoptimized, ...
vm/dart_2/isolates/reload_no_active_stack_test:
Similar to the test above, but instead of having an active stack the
isolates can yield to the event loop, possibly be even descheduled
vm/dart_2/isolates/reload_many_isolates_test:
Similar to the test above, but this test uses many more isolates.
vm/dart_2/isolates/reload_many_isolates_live_and_die_test:
Performs a reload where isolates get spawned and die all the time.
There are always P isolates alive at any given point in time, each
of them spawns children when their parent has died.
Performing a reload catches isolates as various stages of their
lifecycle and can therefore cover a lot of corner cases.
TEST=vm/dart_2/isolates/reload_*_test.dart
Issue https://github.com/dart-lang/sdk/issues/36097
Change-Id: I97039b4084de040b7f2e22f5832a40d57ba398d5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/187461
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
As part of implementing hot-reload for isolate groups, we have to ensure
reloads on a group are performed using the same state of incremental
compiler.
This means we cannot use a specific isolate's information (such as it's
main port) for reloading purposes. Instead we use the unqiue isolate
group id when communicating with the kernel service.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Existing test coverage, future test when hot-reload is fully
implemented with isolate groups.
Change-Id: Ifab39cd2ba689c08507dfab4091cd26951ed54e5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/185320
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
Currently we have things called XPtr which are not what you get from ptr().
Old world:
handle->raw() returns RawObject* (tagged)
raw_obj->ptr() returns RawObject* (untagged)
After 6fe15f6df9:
handle->raw() returns ObjectPtr
obj_ptr->ptr() returns ObjectLayout*
New world:
handle->ptr() returns ObjectPtr
obj_ptr->untag() returns UntaggedObject*
TEST=ci
Change-Id: I6c7f34014cf20737607caaf84979838300d12df2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149367
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
As part of making the compiler and other subsystems independent
of `Isolate` we have to move various state from `Isolate` to
`IsolateGroup`.
The class_table and object_store were already moved to `IsolateGroup`.
This CL only replaces usages of `Isolate::{object_store,class_table}`
with the equivalent in `IsolateGroup`.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Pure refactoring - relying on existing test coverage.
Change-Id: I34a0682d715b054d6c5faff077a513980f59a348
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177126
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
This removes our temporary scaffolding support for JIT isolate groups
(which was implemented by creating a new isolate group, loading the
application kernel into it and then merging the heap into the original
isolate group - maintaining a different object store)
It makes all isolates within a group share the same object store, same
libraries and JITed code. It will be conservative to start with, only
allow running unoptimized code, etc.
We will gradually remove the restrictions imposed by this CL:
https://dart-review.googlesource.com/c/sdk/+/173970
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Tests using --enable-isolate-groups with JIT sharing.
Change-Id: I2bf69a6fe3c905067c4cec2e81613f731c52e5ee
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/175302
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
The former calls the latter with the same arguments, so we could call
the latter directly, though we prefer to use `_startIsolate()` as the
entrypoint.
This fixes test failures in obfuscated mode, where the runtime cannot
find the `_delayEntrypointInvocation` function.
TEST=Fixes -n dartkp-obfuscate-linux-release-x64 ffi_2/dylib_isolates_test
Change-Id: I062fc16658f90750439f304849daa3911d3a1b89
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/171946
Reviewed-by: Tess Strickland <sstrickl@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
The Isolate.spawn() is part of our dart:isolate library implementation,
it should therefore preferrably live under runtime/lib folder.
This CL does that as well as removing some special message handling
logic by using the new `Dart_RunLoopAsync()` C API, which results in
net removal of code.
As a nice side-effect it also makes isolate spawning slightly faster due
to avoiding extra safepoint/vm<->native transitions.
Issue https://github.com/dart-lang/sdk/issues/44088
TEST=Changes existing implementation, have existing test coverage for it.
Change-Id: I00607a1436946552bbe12e8e23062e8f743d4f11
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/171731
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Dart_CreateLightweightIsolate API:
This API can be used by embedders to create a lightweight isolate
(inside an existing isolate group).
It is the analogous to Dart_CreateIsolateGroup - though taking a
parent isolate as parameter (inside whose IG we create a new isolate)
instead of taking kernel/snapshot data.
Right now this API works on AOT and returns an error in JIT, both cases
are covered by the test.
Dart_RunLoopAsync:
The API can be used by embedders to transfer ownership of an isolate to
the VM, which will take care of running the message handling loop and
shuts the isolate down once the last receive port has been closed.
It does allow listening to error/exit events generated by the message
loop implementation as well as allows setting errors-are-fatal,
effectively the same event-loop related parameters from the
`Isolate.spawn()` API, just in Dart.
It's the embedders responsibility to first launch initial dart code
which will take care of responding to events (i.e. directly/indirectly
open a receive port) - otherwise the isolate cannot be talked to and
would immediately shut down.
Since our vm/cc tests do support running in AOT, we use a hybrid
approach to test the functionality: We let a normal Dart test call a
small C wrapper using FFI, to create a lightweight isolate, run it on a
new thread and join that thread.
TEST=vm/dart{,_2}/isolates/dart_api_create_lightweight_isolate_test
Issue https://github.com/dart-lang/sdk/issues/36097
Closes https://github.com/dart-lang/sdk/issues/44088
Change-Id: Id77ba928793fdb517f6cb7e8130df98a0366ddd6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/170983
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
When Dart invokes Isolate.spawn the Dart VM calls out to the embedder to
create an isolate (group) or initialize it (in case of lightweight
isolates).
* If the embedder doesn't implement this functionality or fails to
perform the creation/initialization, it will signal this failure
via the return value it gives to the VM in the call back
implementation (i.e. Dart_InitializeParams.create_group and
Dart_InitializeParams.initialize_isolate}).
* If the embeder sucessfully completed it's work, the VM owns the
isolate after the embedder call returns. The VM is then responsible
for running it.
It is an undocumented invariant atm that the embedder is responsible
to make the isolate runnable if it signals the VM that isolate was
sucessfully created/initialized.
=> If it does not do that, we have effectively an isolate leak.
=> Though right now seemingly all of our embedders to that correctly.
To avoid this unintentional isolate leak we make the isolate runnable
ourselves if embedder callback was successful but did not make it
runnable itself.
=> This also avoids unnecessary ceremony code in the embedders that
look like this:
Dart_ExitIsolate();
Dart_IsolateMakeRunnable(child);
Dart_EnterIsolate(child);
The implementation of `Dart_IsolateMakeRunnable()` had an untested and
unused code path that caused running the isolate (on a thread pool).
This is not documented and can lead to bugs because often the
embedders enter the isolate right after making it runnable (e.g. above
code sequence) - which would be racing with the spawned message handler
thread.
=> Furtunately our embedders are well behaved and make the isolate
runnable during the callback.
=> As a safeguard we'll make `Dart_IsolateMakeRunnable()` return an
error if it's called outside the callback (which we can detect by
the presense of a spawn state)
Issue https://github.com/dart-lang/sdk/issues/44088
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Changes internal details of implementation which is already covered by tests.
Change-Id: Ieef316cc0807d99f2fcb1fbd56bbc9c41e904ba8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/170882
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
prevent repeated port allocations
Flutter makes heavy use of short-lived Timers which currently causes
repeated opening/closing of the Timer port. This change allows for
RawReceivePorts to be set active / inactive, allowing for a port to be
kept open but not considered alive.
Flutter benchmark changes:
Before dart-lang/sdk@d5118d5: "notifyListener2_iteration": 545.0
After dart-lang/sdk@d5118d5: "notifyListener2_iteration": 1639.0
With fix: "notifyListener2_iteration": 629.0
Fixes https://github.com/flutter/flutter/issues/69583
TEST=Updated port state tests and verified change against Flutter's microbenchmarks
Change-Id: I50ff1a1b0f1f29bcdac958e41c66429e9586fba2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/171628
Commit-Queue: Ben Konyi <bkonyi@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
This reverts commit 5bf9163e1b.
Reason for revert: Tests failing on bots.
Original change's description:
> [ Service / dart:isolate ] Added getPorts RPC and 'debugName' optional
> parameter for ReceivePort and RawReceivePort
>
> This change collects additional information related to ReceivePort
> allocation locations and an optional debug name that will be displayed
> by tooling. ReceivePort is now a special InstanceKind and a ReceivePort
> @Instance will include the port ID, allocation stack trace, and debug
> name.
>
> Change-Id: I003cfff2b7649218e37d9b653c0e953df5d992e7
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/167902
> Reviewed-by: Ryan Macnak <rmacnak@google.com>
TBR=bkonyi@google.com,rmacnak@google.com,asiva@google.com
Change-Id: I39c3abb07c8c40c158eb4549749b076399bccce9
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/169160
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>
parameter for ReceivePort and RawReceivePort
This change collects additional information related to ReceivePort
allocation locations and an optional debug name that will be displayed
by tooling. ReceivePort is now a special InstanceKind and a ReceivePort
@Instance will include the port ID, allocation stack trace, and debug
name.
Change-Id: I003cfff2b7649218e37d9b653c0e953df5d992e7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/167902
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Daco Harkes