diff options
| -rw-r--r-- | indra/llcommon/tests/threadsafeschedule_test.cpp | 4 | ||||
| -rw-r--r-- | indra/llcommon/tests/workqueue_test.cpp | 23 | ||||
| -rw-r--r-- | indra/llcommon/workqueue.h | 167 |
3 files changed, 134 insertions, 60 deletions
diff --git a/indra/llcommon/tests/threadsafeschedule_test.cpp b/indra/llcommon/tests/threadsafeschedule_test.cpp index af67b9f492..c421cc7b1c 100644 --- a/indra/llcommon/tests/threadsafeschedule_test.cpp +++ b/indra/llcommon/tests/threadsafeschedule_test.cpp @@ -46,11 +46,11 @@ namespace tut // the real time required for each push() call. Explicitly increment // the timestamp for each one -- but since we're passing explicit // timestamps, make the queue reorder them. - queue.push(Queue::TimeTuple(Queue::Clock::now() + 20ms, "ghi")); + queue.push(Queue::TimeTuple(Queue::Clock::now() + 200ms, "ghi")); // Given the various push() overloads, you have to match the type // exactly: conversions are ambiguous. queue.push("abc"s); - queue.push(Queue::Clock::now() + 10ms, "def"); + queue.push(Queue::Clock::now() + 100ms, "def"); queue.close(); auto entry = queue.pop(); ensure_equals("failed to pop first", std::get<0>(entry), "abc"s); diff --git a/indra/llcommon/tests/workqueue_test.cpp b/indra/llcommon/tests/workqueue_test.cpp index d5405400fd..b69df49d33 100644 --- a/indra/llcommon/tests/workqueue_test.cpp +++ b/indra/llcommon/tests/workqueue_test.cpp @@ -138,7 +138,8 @@ namespace tut [](){ return 17; }, // Note that a postTo() *callback* can safely bind a reference to // a variable on the invoking thread, because the callback is run - // on the invoking thread. + // on the invoking thread. (Of course the bound variable must + // survive until the callback is called.) [&result](int i){ result = i; }); // this should post the callback to main qptr->runOne(); @@ -156,4 +157,24 @@ namespace tut main.runPending(); ensure_equals("failed to run string callback", alpha, "abc"); } + + template<> template<> + void object::test<5>() + { + set_test_name("postTo with void return"); + WorkQueue main("main"); + auto qptr = WorkQueue::getInstance("queue"); + std::string observe; + main.postTo( + qptr, + // The ONLY reason we can get away with binding a reference to + // 'observe' in our work callable is because we're directly + // calling qptr->runOne() on this same thread. It would be a + // mistake to do that if some other thread were servicing 'queue'. + [&observe](){ observe = "queue"; }, + [&observe](){ observe.append(";main"); }); + qptr->runOne(); + main.runOne(); + ensure_equals("failed to run both lambdas", observe, "queue;main"); + } } // namespace tut diff --git a/indra/llcommon/workqueue.h b/indra/llcommon/workqueue.h index cfae2019dc..deef3c8e84 100644 --- a/indra/llcommon/workqueue.h +++ b/indra/llcommon/workqueue.h @@ -115,62 +115,7 @@ namespace LL // code. template <typename CALLABLE, typename FOLLOWUP> bool postTo(WorkQueue::weak_t target, - const TimePoint& time, CALLABLE&& callable, FOLLOWUP&& callback) - { - // We're being asked to post to the WorkQueue at target. - // target is a weak_ptr: have to lock it to check it. - auto tptr = target.lock(); - if (! tptr) - // can't post() if the target WorkQueue has been destroyed - return false; - - // Here we believe target WorkQueue still exists. Post to it a - // lambda that packages our callable, our callback and a weak_ptr - // to this originating WorkQueue. - tptr->post( - time, - [reply = super::getWeak(), - callable = std::move(callable), - callback = std::move(callback)] - () - { - // Call the callable in any case -- but to minimize - // copying the result, immediately bind it into a reply - // lambda. The reply lambda also binds the original - // callback, so that when we, the originating WorkQueue, - // finally receive and process the reply lambda, we'll - // call the bound callback with the bound result -- on the - // same thread that originally called postTo(). - auto rlambda = - [result = callable(), - callback = std::move(callback)] - () - { callback(std::move(result)); }; - // Check if this originating WorkQueue still exists. - // Remember, the outer lambda is now running on a thread - // servicing the target WorkQueue, and real time has - // elapsed since postTo()'s tptr->post() call. - // reply is a weak_ptr: have to lock it to check it. - auto rptr = reply.lock(); - if (rptr) - { - // Only post reply lambda if the originating WorkQueue - // still exists. If not -- who would we tell? Log it? - try - { - rptr->post(std::move(rlambda)); - } - catch (const Closed&) - { - // Originating WorkQueue might still exist, but - // might be Closed. Same thing: just discard the - // callback. - } - } - }); - // looks like we were able to post() - return true; - } + const TimePoint& time, CALLABLE&& callable, FOLLOWUP&& callback); /** * Post work to another WorkQueue, requesting a specific callback to @@ -183,7 +128,8 @@ namespace LL bool postTo(WorkQueue::weak_t target, CALLABLE&& callable, FOLLOWUP&& callback) { - return postTo(target, TimePoint::clock::now(), std::move(callable), std::move(callback)); + return postTo(target, TimePoint::clock::now(), + std::move(callable), std::move(callback)); } /*--------------------------- worker API ---------------------------*/ @@ -231,6 +177,17 @@ namespace LL bool runUntil(const TimePoint& until); private: + template <typename CALLABLE, typename FOLLOWUP> + static auto makeReplyLambda(CALLABLE&& callable, FOLLOWUP&& callback); + + /// general case: arbitrary C++ return type + template <typename CALLABLE, typename FOLLOWUP, typename RETURNTYPE> + struct MakeReplyLambda; + + /// specialize for CALLABLE returning void + template <typename CALLABLE, typename FOLLOWUP> + struct MakeReplyLambda<CALLABLE, FOLLOWUP, void>; + static void error(const std::string& msg); static std::string makeName(const std::string& name); void callWork(const Queue::DataTuple& work); @@ -329,6 +286,102 @@ namespace LL getWeak(), TimePoint::clock::now(), interval, std::move(callable))); } + template <typename CALLABLE, typename FOLLOWUP, typename RETURNTYPE> + struct WorkQueue::MakeReplyLambda + { + auto operator()(CALLABLE&& callable, FOLLOWUP&& callback) + { + // Call the callable in any case -- but to minimize + // copying the result, immediately bind it into the reply + // lambda. The reply lambda also binds the original + // callback, so that when we, the originating WorkQueue, + // finally receive and process the reply lambda, we'll + // call the bound callback with the bound result -- on the + // same thread that originally called postTo(). + return + [result = std::forward<CALLABLE>(callable)(), + callback = std::move(callback)] + () + { callback(std::move(result)); }; + } + }; + + /// specialize for CALLABLE returning void + template <typename CALLABLE, typename FOLLOWUP> + struct WorkQueue::MakeReplyLambda<CALLABLE, FOLLOWUP, void> + { + auto operator()(CALLABLE&& callable, FOLLOWUP&& callback) + { + // Call the callable, which produces no result. + std::forward<CALLABLE>(callable)(); + // This reply lambda binds the original callback, so + // that when we, the originating WorkQueue, finally + // receive and process the reply lambda, we'll call + // the bound callback -- on the same thread that + // originally called postTo(). + return [callback = std::move(callback)](){ callback(); }; + } + }; + + template <typename CALLABLE, typename FOLLOWUP> + auto WorkQueue::makeReplyLambda(CALLABLE&& callable, FOLLOWUP&& callback) + { + return MakeReplyLambda<CALLABLE, FOLLOWUP, + decltype(std::forward<CALLABLE>(callable)())>() + (std::move(callable), std::move(callback)); + } + + template <typename CALLABLE, typename FOLLOWUP> + bool WorkQueue::postTo(WorkQueue::weak_t target, + const TimePoint& time, CALLABLE&& callable, FOLLOWUP&& callback) + { + // We're being asked to post to the WorkQueue at target. + // target is a weak_ptr: have to lock it to check it. + auto tptr = target.lock(); + if (! tptr) + // can't post() if the target WorkQueue has been destroyed + return false; + + // Here we believe target WorkQueue still exists. Post to it a + // lambda that packages our callable, our callback and a weak_ptr + // to this originating WorkQueue. + tptr->post( + time, + [reply = super::getWeak(), + callable = std::move(callable), + callback = std::move(callback)] + () + { + // Make a reply lambda to repost to THIS WorkQueue. + // Delegate to makeReplyLambda() so we can partially + // specialize on void return. + auto rlambda = makeReplyLambda(std::move(callable), std::move(callback)); + // Check if this originating WorkQueue still exists. + // Remember, the outer lambda is now running on a thread + // servicing the target WorkQueue, and real time has + // elapsed since postTo()'s tptr->post() call. + // reply is a weak_ptr: have to lock it to check it. + auto rptr = reply.lock(); + if (rptr) + { + // Only post reply lambda if the originating WorkQueue + // still exists. If not -- who would we tell? Log it? + try + { + rptr->post(std::move(rlambda)); + } + catch (const Closed&) + { + // Originating WorkQueue might still exist, but + // might be Closed. Same thing: just discard the + // callback. + } + } + }); + // looks like we were able to post() + return true; + } + } // namespace LL #endif /* ! defined(LL_WORKQUEUE_H) */ |