Hotfix run each request in bound thread #4080
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When using foreign libraries that use thread-local state, a program must ensure that foreign calls are always made from the same OS thread, by way of making these calls in _bound threads_, see https://downloads.haskell.org/ghc/latest/docs/libraries/base-4.20.0.0-1f57/Control-Concurrent.html#g:8 This PR * adds a flag to the generic RPC server in `kore-rpc-types` to request running workers in bound threads. The server will use `forkOS` instead of `forkIO` in this case. * requests running with bound threads when an LLVM backend library is used. This _should_ protect us against problems related to using thread-local storage in the LLVM backend. Needs to be thoroughly tested before merging, because issues only materialised in proofs with substantial workload and parallel exploration.
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…ll block" This reverts commit 207d6b1. The branch crashed in a proof with 16x parallelism, trying with `Safe` calls again to narrow down why.
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Fixes a problem with recently-introduced thread-local storage in the LLVM backend.
We have to make sure that all foreign calls relating to an LLVM-based term evaluation use the same OS thread, which can only be achieved via bound threads .
This PR
kore-rpc-typesto request processing requests in bound threadskore-rpc-boosteruses this flag for bound threads when an LLVM backend library is usedThis should protect us against problems related to using thread-local storage in the LLVM backend. Needs to be thoroughly tested before merging, because issues only materialised in proofs with substantial workload and parallel exploration.
Branch HOTFIX-use-bound-threads-for-request-workers is a simple take on this, running the whole worker thread in the server as a bound thread. This version here only runs the single request in a bound thread, and also declares the LLVM calls
unsafebecause they won't read HS heap data and never call back into Haskell.