This will allow async handlers to be added that return void or Error::success().
Such handlers are expected to be common, since one of the primary uses of
addAsyncHandler is to run the body of the handler in a detached thread, in which
case the main handler returns immediately and does not need to provide an Error
value.
llvm-svn: 312746
The tests were failing due to an occasional deadlock in SerializationTraits
for Error: Both serializers and deserializers were protected by a single
mutex and in the unit test (where both ends of the RPC are in the same
process) one side might obtain the mutex, then block waiting for input,
leaving the other side of the connection unable to obtain the mutex to
write the data the first side was waiting for. Splitting the mutex into
two (one for serialization, one for deserialization) appears to have fixed the
issue.
llvm-svn: 300286
This patch allows Error and Expected types to be passed to and returned from
RPC functions.
Serializers and deserializers for custom error types (types deriving from the
ErrorInfo class template) can be registered with the SerializationTraits for
a given channel type (see registerStringError in RPCSerialization.h for an
example), allowing a given custom type to be sent/received. Unregistered types
will be serialized/deserialized as StringErrors using the custom type's log
message as the error string.
llvm-svn: 300167
handler args.
The specialization just inherits from the std::decay'd response handler type.
This allows member functions (via MemberFunctionWrapper) to be used as async
handlers.
llvm-svn: 295151
Launch policies provided a mechanism for running RPC handlers on a background
thread (unblocking the main RPC receiver thread). Async handlers generalize
this by passing the responder function (the function that sends the RPC return
value) as an argument to the handler. The handler can optionally do its work on
a background thread (the same way launch policies do), but can also (a) can
inspect the call arguments before deciding to run the work on a different
thread, or (b) can use the responder in a subsequent RPC call (e.g. in the
handler of a callAsync), allowing the handler to call back to the originator (or
to a 3rd party) without blocking the listener thread, and without launching a
new thread.
llvm-svn: 295030
This refactor allows parallel calls to be made via an arbitrary async call
dispatcher. In particular, this allows ParallelCallGroup to be used with
derived RPC classes that expose custom async RPC call operations.
llvm-svn: 292891
APICalls allows groups of functions to be composed into an API that can be
registered as a unit with an RPC endpoint. Doing registration on a-whole API
basis (rather than per-function) allows missing API functions to be detected
early.
APICalls also allows Function membership to be tested at compile-time. This
allows clients to write static assertions that functions to be called are
members of registered APIs.
llvm-svn: 291380
multiple asynchronous RPC calls.
ParallelCallGroup allows multiple asynchronous calls to be dispatched,
and provides a wait method that blocks until all asynchronous calls have
been executed on the remote and all return value handlers run on the
local machine.
This will allow, for example, the JIT client to issue memory allocation calls
for all sections in parallel, then block until all memory has been allocated
on the remote and the allocated addresses registered with the client, at which
point the JIT client can proceed to applying relocations.
llvm-svn: 290523
This unit test infinite-looped on s390x due to a thread_yield being optimized
out. I've updated the QueueChannel class (where thread_yield was called) to use
a condition variable instead. This should cause the unit test to behave
correctly.
llvm-svn: 287121
This broke s390x due to a bug in the QueueChannel implementation that led to it
infinite-looping. Disabling it while I look into a fix.
llvm-svn: 286917
return types.
This class allows user provided handlers to return either error-wrapped types
or plain types. In the latter case, the plain type is wrapped with a success
value of Error or Expected<T> type to fit it into the rest of the serialization
machinery.
This patch allows us to remove the RPC unit-test workaround added in r286646.
llvm-svn: 286701
return type.
This should be fixed permanently by having the RPCUtils header recognize the
ErrorSuccess type. I'll commit that in a follow up patch.
llvm-svn: 286646
(1) Add support for function key negotiation.
The previous version of the RPC required both sides to maintain the same
enumeration for functions in the API. This means that any version skew between
the client and server would result in communication failure.
With this version of the patch functions (and serializable types) are defined
with string names, and the derived function signature strings are used to
negotiate the actual function keys (which are used for efficient call
serialization). This allows clients to connect to any server that supports a
superset of the API (based on the function signatures it supports).
(2) Add a callAsync primitive.
The callAsync primitive can be used to install a return value handler that will
run as soon as the RPC function's return value is sent back from the remote.
(3) Launch policies for RPC function handlers.
The new addHandler method, which installs handlers for RPC functions, takes two
arguments: (1) the handler itself, and (2) an optional "launch policy". When the
RPC function is called, the launch policy (if present) is invoked to actually
launch the handler. This allows the handler to be spawned on a background
thread, or added to a work list. If no launch policy is used, the handler is run
on the server thread itself. This should only be used for short-running
handlers, or entirely synchronous RPC APIs.
(4) Zero cost cross type serialization.
You can now define serialization from any type to a different "wire" type. For
example, this allows you to call an RPC function that's defined to take a
std::string while passing a StringRef argument. If a serializer from StringRef
to std::string has been defined for the channel type this will be used to
serialize the argument without having to construct a std::string instance.
This allows buffer reference types to be used as arguments to RPC calls without
requiring a copy of the buffer to be made.
llvm-svn: 286620
This reverts commit r280016, and the followups of r280017, r280027,
r280051, r280058, and r280059.
MSVC's implementation of std::promise does not get along with
llvm::Error. It uses its promised value too much like a normal value
type.
llvm-svn: 280100
behaviors, and add a callB (blacking call) primitive.
callB is a blocking call primitive for threaded code where the RPC responses are
being processed on a separate thread. (For single threaded code callST should
continue to be used instead).
No unit test yet: Last time I commited a threaded unit test it deadlocked on
one of the s390x builders. I'll try to re-enable that test first, and add a new
test if I can sort out the deadlock issue.
llvm-svn: 280051
Optional.
For void functions the return type of a nonblocking call changes from
Expected<future<Optional<bool>>> to Expected<future<Error>>, and for functions
returning T the return type changes from Expected<future<Optional<T>>> to
Expected<future<Expected<T>>>.
Inner results need to be checked (since the RPC connection may have dropped
out before a result came back) and Error/Expected provide stronger checking
requirements. It also allows us drop the crufty 'optionalToError' function and
just collapse Errors in the single-threaded call primitives.
llvm-svn: 280016
This replaces use of std::error_code and ErrorOr in the ORC RPC support library
with Error and Expected. This required updating the OrcRemoteTarget API, Client,
and server code, as well as updating the Orc C API.
This patch also fixes several instances where Errors were dropped.
llvm-svn: 267457
Three problems:
1. <future> can't be easily used. If you must use it, see
include/Support/ThreadPool.h for how.
2. constexpr problems, even after 266588.
3. Move assignment operators can't be defaulted in MSVC2013.
llvm-svn: 266615
asynchronous call/handle. Also updates the ORC remote JIT API to use the new
scheme.
The previous version of the RPC tools only supported void functions, and
required the user to manually call a paired function to return results. This
patch replaces the Procedure typedef (which only supported void functions) with
the Function typedef which supports return values, e.g.:
Function<FooId, int32_t(std::string)> Foo;
The RPC primitives and channel operations are also expanded. RPC channels must
support four new operations: startSendMessage, endSendMessage,
startRecieveMessage and endRecieveMessage, to handle channel locking. In
addition, serialization support for tuples to RPCChannels is added to enable
multiple return values.
The RPC primitives are expanded from callAppend, call, expect and handle, to:
appendCallAsync - Make an asynchronous call to the given function.
callAsync - The same as appendCallAsync, but calls send on the channel when
done.
callSTHandling - Blocking call for single-threaded code. Wraps a call to
callAsync then waits on the result, using a user-supplied
handler to handle any callbacks from the remote.
callST - The same as callSTHandling, except that it doesn't handle
callbacks - it expects the result to be the first return.
expect and handle - as before.
handleResponse - Handle a response from the remote.
waitForResult - Wait for the response with the given sequence number to arrive.
llvm-svn: 266581
This patch adds utilities to ORC for managing a remote JIT target. It consists
of:
1. A very primitive RPC system for making calls over a byte-stream. See
RPCChannel.h, RPCUtils.h.
2. An RPC API defined in the above system for managing memory, looking up
symbols, creating stubs, etc. on a remote target. See OrcRemoteTargetRPCAPI.h.
3. An interface for creating high-level JIT components (memory managers,
callback managers, stub managers, etc.) that operate over the RPC API. See
OrcRemoteTargetClient.h.
4. A helper class for building servers that can handle the RPC calls. See
OrcRemoteTargetServer.h.
The system is designed to work neatly with the existing ORC components and
functionality. In particular, the ORC callback API (and consequently the
CompileOnDemandLayer) is supported, enabling lazy compilation of remote code.
Assuming this doesn't trigger any builder failures, a follow-up patch will be
committed which tests these utilities by using them to replace LLI's existing
remote-JITing demo code.
llvm-svn: 257305
Lang Hames