This CL also removes ability to assign names to mutexes which was
added in c25ebfff96 but did not yield
any interesting data.
TEST=ci
CoreLibraryReviewExempt: Changes to dart:concurrent only.
Cq-Include-Trybots: luci.dart.try:vm-fuchsia-release-x64-try,vm-win-debug-x64-try,vm-win-release-x64-try,vm-aot-linux-product-x64-try
Change-Id: Id41e1d29832f6008e02f0a571ee67564e1a84224
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/375300
Reviewed-by: Martin Kustermann <kustermann@google.com>
This relands https://dart-review.googlesource.com/c/sdk/+/205633
but without renaming TARGET_OS_IPHONE to DART_TARGET_OS_IPHONE.
It also changes uses of TARGET_OS_IOS to
DART_TARGET_OS_MACOS_IOS to be consistent with the rest of the
VM.
TargetConditionals.h for XCode 13 defines several
TARGET_OS_* preprocessor symbols that confuse the
Dart build. There is probably a more targeted fix
for this, but renaming the symbols that Dart uses
will also prevent this problem if more symbols
are added to the platform headers in the future.
See: https://github.com/dart-lang/sdk/issues/46499
TEST=It builds.
Change-Id: Ie775c19dd23cfdf5f65e5ebc6ee4ec3a561676fa
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/205860
Commit-Queue: Zach Anderson <zra@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
TargetConditionals.h for XCode 13 defines several
TARGET_OS_* preprocessor symbols that confuse the
Dart build. There is probably a more targeted fix
for this, but renaming the symbols that Dart uses
will also prevent this problem if more symbols
are added to the platform headers in the future.
See: https://github.com/dart-lang/sdk/issues/46499
TEST=It builds.
Change-Id: I3b33a03b4a9a14b76d55fe12f8cdefec4b3c3664
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/205633
Commit-Queue: Zach Anderson <zra@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Code path Monitor::Wait that handles timeout contains a race between removing
waiter from the list and another thread signaling waiter's event:
T1: WaitForSingleObject(wait_data->event_, ...) returns with WAIT_TIMEOUT
T2: SetEvent(wait_data->event_)
T1: data_.RemoveWaiter(wait_data->event_)
This race leaves wait_data->event_ signaled, which breaks an important invariant
the method relies on: if WaitForSingleObject returns successfully (neither
timedout nor failed), that implies that wait_data was removed from the
waiters list by the method that signaled the event (SignalAndRemoveAllWaiters
or SignalAndRemoveFirstWaiter). However if wait_data->event_ is left signaled
the next invocation to WaitForSingleObject will return prior to any invocation
of SignalAndRemoveAllWaiters/SignalAndRemoveFirstWaiter, which means that
wait_data->event_ will be left in the list, which can lead to all sorts of
bugs, for example:
T1: // Assuming that wait_data WD1 for thread T1 is left with signaled event.
T1: ml.Wait() | waiters list: WD1
T1: | WaitForSingleObject(...) returns "spuriously" | waiters list: WD1
T1: // WD1 is still on the waiters list, even though |
T1 // it is not waiting anymore | waiters list: WD1
|
T2: ml.Wait() | waiters list: WD1 -> WD2
|
T1: // wait on the same monitor again |
T1: ml.Wait() | waiters list: WD1 -> WD2
T1: | GetMonitorWaitDataForThread() | waiters list: WD1 -> WD2
T1: | | wait_data->next_ = NULL | waiters list: WD1
T3: // Notify all waiters. Only T1 will wake up!
T3: ml.NotifyAll()
Notice how waiting on the same monitor caused us to corrupt the singled
linked list of waiters, because GetMonitorWaitDataForThread(...) does
wait_data->next_ = NULL - which means that if WD1 was accidentally left
in the list of waiters then all elements on that list after WD1 are lost.
This means that NotifyAll will not wake up all threads.
This was causing deadlocks in GC (#29261) by breaking ThreadBarrier logic.
Fixes https://github.com/dart-lang/sdk/issues/29261
Bug:
Change-Id: Ia61efa065bc7db8fe4bbf549032f35932356a0f4
Reviewed-on: https://dart-review.googlesource.com/20760
Reviewed-by: Zach Anderson <zra@google.com>
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Like HOST_ARCH_*, HOST_OS_* describes the OS the VM is running on, which may be different from the OS the VM is generating code for during AOT compilation.
Currently we conflate the two when emitting AOT as assembly, and we get away with it because Flutter only uses assembly for targeting iOS and one can only target iOS from a Mac, but we expect to use assembly for Android as well so native tools can unwind Dart frames.
R=zra@google.com
Review-Url: https://codereview.chromium.org/2750843003 .
Also:
- Reaps exited threads in the thread pool before putting
a thread on the idle list so that a new arriving task
isn't blocked on a supposedly idle thread in the middle
of a join.
- Stops trying to join eventhandler threads on
Windows. Now that we're using the correct exit() call,
we probably don't have to worry about exit code pollution,
so joining the threads is unnecessary.
related #26400R=asiva@google.com, iposva@google.com
Review URL: https://codereview.chromium.org/1978153002 .
Ryan Macnak