On Thu, 23 Jan 2025 14:26:23 GMT, Maurizio Cimadamore <mcimadam...@openjdk.org> wrote:
>> Ah no, the allocate fails of course: >> >> java.lang.WrongThreadException: Attempted access outside owning thread >> at >> java.base/jdk.internal.foreign.MemorySessionImpl.wrongThread(MemorySessionImpl.java:322) >> at >> java.base/jdk.internal.misc.ScopedMemoryAccess$ScopedAccessError.newRuntimeException(ScopedMemoryAccess.java:114) >> at >> java.base/jdk.internal.foreign.MemorySessionImpl.checkValidState(MemorySessionImpl.java:217) >> at >> java.base/jdk.internal.foreign.SegmentFactories.allocateSegment(SegmentFactories.java:181) >> at >> java.base/jdk.internal.foreign.ArenaImpl.allocateNoInit(ArenaImpl.java:52) >> at java.base/jdk.internal.foreign.ArenaImpl.allocate(ArenaImpl.java:57) >> at java.base/jdk.internal.foreign.ArenaImpl.allocate(ArenaImpl.java:31) >> at >> java.base/java.lang.foreign.SegmentAllocator.allocate(SegmentAllocator.java:644) >> at >> java.base/jdk.internal.foreign.abi.BufferStack$PerThread.<init>(BufferStack.java:73) >> at >> java.base/jdk.internal.foreign.abi.BufferStack$1.initialValue(BufferStack.java:50) >> at >> java.base/jdk.internal.foreign.abi.BufferStack$1.initialValue(BufferStack.java:47) >> at java.base/java.lang.ThreadLocal.setInitialValue(ThreadLocal.java:224) >> at java.base/java.lang.ThreadLocal.get(ThreadLocal.java:193) >> at >> java.base/java.lang.ThreadLocal.getCarrierThreadLocal(ThreadLocal.java:180) >> at java.base/java.lang.System$1.getCarrierThreadLocal(System.java:2237) >> at >> java.base/jdk.internal.misc.CarrierThreadLocal.get(CarrierThreadLocal.java:39) >> at >> java.base/jdk.internal.foreign.abi.BufferStack.pushFrame(BufferStack.java:61) >> at TestBufferStack.lambda$stress$1(TestBufferStack.java:113) > >> Ah no, the allocate fails of course: >> >> ``` >> java.lang.WrongThreadException: Attempted access outside owning thread >> at >> java.base/jdk.internal.foreign.MemorySessionImpl.wrongThread(MemorySessionImpl.java:322) >> at >> java.base/jdk.internal.misc.ScopedMemoryAccess$ScopedAccessError.newRuntimeException(ScopedMemoryAccess.java:114) >> at >> java.base/jdk.internal.foreign.MemorySessionImpl.checkValidState(MemorySessionImpl.java:217) >> at >> java.base/jdk.internal.foreign.SegmentFactories.allocateSegment(SegmentFactories.java:181) >> at >> java.base/jdk.internal.foreign.ArenaImpl.allocateNoInit(ArenaImpl.java:52) >> at java.base/jdk.internal.foreign.ArenaImpl.allocate(ArenaImpl.java:57) >> at java.base/jdk.internal.foreign.ArenaImpl.allocate(ArenaImpl.java:31) >> at >> java.base/java.lang.foreign.SegmentAllocator.allocate(SegmentAllocator.java:644) >> at >> java.base/jdk.internal.foreign.abi.BufferStack$PerThread.<init>(BufferStack.java:73) >> at >> java.base/jdk.internal.foreign.abi.BufferStack$1.initialValue(BufferStack.java:50) >> at >> java.base/jdk.internal.foreign.abi.BufferStack$1.initialValue(BufferStack.java:47) >> at java.base/java.lang.ThreadLocal.setInitialValue(ThreadLocal.java:224) >> at java.base/java.lang.ThreadLocal.get(ThreadLocal.java:193) >> at >> java.base/java.lang.ThreadLocal.getCarrierThreadLocal(ThreadLocal.java:180) >> at java.base/java.lang.System$1.getCarrierThreadLocal(System.java:2237) >> at >> java.base/jdk.internal.misc.CarrierThreadLocal.get(CarrierThreadLocal.java:39) >> at >> java.base/jdk.internal.foreign.abi.BufferStack.pushFrame(BufferStack.java:61) >> at TestBufferStack.lambda$stress$1(TestBufferStack.java:113) >> ``` > > I was under the impression (which appears incorrect) that `initialValue` > would be called by the carrier thread as well. So, we basically have a > mismatch where `initialValue` is called with thread A, but `terminate` is > called on thread B ? Exactly. initialValue happens on-demand, not upfront, i.e. in the very moment the VT calls get(). Whereas terminate happens as the last action of the CT. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/23142#discussion_r1927071961
