diff options
Diffstat (limited to 'indra/llcommon')
| -rw-r--r-- | indra/llcommon/llcoros.cpp | 58 | ||||
| -rw-r--r-- | indra/llcommon/llcoros.h | 24 |
2 files changed, 56 insertions, 26 deletions
diff --git a/indra/llcommon/llcoros.cpp b/indra/llcommon/llcoros.cpp index d16bf0160b..e84fa6aea0 100644 --- a/indra/llcommon/llcoros.cpp +++ b/indra/llcommon/llcoros.cpp @@ -44,16 +44,25 @@ void LLCoros::no_cleanup(CoroData*) {} // CoroData for the currently-running coroutine. Use a thread_specific_ptr // because each thread potentially has its own distinct pool of coroutines. -// This thread_specific_ptr does NOT own the CoroData object! That's owned by -// LLCoros::mCoros. It merely identifies it. For this reason we instantiate -// it with a no-op cleanup function. -boost::thread_specific_ptr<LLCoros::CoroData> -LLCoros::sCurrentCoro(LLCoros::no_cleanup); +LLCoros::Current::Current() +{ + // Use a function-static instance so this thread_specific_ptr is + // instantiated on demand. Since we happen to know it's consumed by + // LLSingleton, this is likely to happen before the runtime has finished + // initializing module-static data. For the same reason, we can't package + // this pointer in an LLSingleton. + + // This thread_specific_ptr does NOT own the CoroData object! That's owned + // by LLCoros::mCoros. It merely identifies it. For this reason we + // instantiate it with a no-op cleanup function. + static boost::thread_specific_ptr<LLCoros::CoroData> sCurrent(LLCoros::no_cleanup); + mCurrent = &sCurrent; +} //static LLCoros::CoroData& LLCoros::get_CoroData(const std::string& caller) { - CoroData* current = sCurrentCoro.get(); + CoroData* current = Current(); if (! current) { LL_ERRS("LLCoros") << "Calling " << caller << " from non-coroutine context!" << LL_ENDL; @@ -79,20 +88,23 @@ bool LLCoros::get_consuming() return get_CoroData("get_consuming()").mConsuming; } -llcoro::Suspending::Suspending(): - mSuspended(LLCoros::sCurrentCoro.get()) +llcoro::Suspending::Suspending() { - // Revert mCurrentCoro to the value it had at the moment we last switched + LLCoros::Current current; + // Remember currently-running coroutine: we're about to suspend it. + mSuspended = current; + // Revert Current to the value it had at the moment we last switched // into this coroutine. - LLCoros::sCurrentCoro.reset(mSuspended->mPrev); + current.reset(mSuspended->mPrev); } llcoro::Suspending::~Suspending() { + LLCoros::Current current; // Okay, we're back, update our mPrev - mSuspended->mPrev = LLCoros::sCurrentCoro.get(); - // and reinstate our sCurrentCoro. - LLCoros::sCurrentCoro.reset(mSuspended); + mSuspended->mPrev = current; + // and reinstate our Current. + current.reset(mSuspended); } LLCoros::LLCoros(): @@ -212,7 +224,7 @@ bool LLCoros::kill(const std::string& name) std::string LLCoros::getName() const { - CoroData* current = sCurrentCoro.get(); + CoroData* current = Current(); if (! current) { // not in a coroutine @@ -228,8 +240,8 @@ void LLCoros::setStackSize(S32 stacksize) } // Top-level wrapper around caller's coroutine callable. This function accepts -// the coroutine library's implicit coro::self& parameter and sets sCurrentSelf -// but does not pass it down to the caller's callable. +// the coroutine library's implicit coro::self& parameter and saves it, but +// does not pass it down to the caller's callable. void LLCoros::toplevel(coro::self& self, CoroData* data, const callable_t& callable) { // capture the 'self' param in CoroData @@ -237,8 +249,8 @@ void LLCoros::toplevel(coro::self& self, CoroData* data, const callable_t& calla // run the code the caller actually wants in the coroutine callable(); // This cleanup isn't perfectly symmetrical with the way we initially set - // data->mPrev, but this is our last chance to reset mCurrentCoro. - sCurrentCoro.reset(data->mPrev); + // data->mPrev, but this is our last chance to reset Current. + Current().reset(data->mPrev); } /***************************************************************************** @@ -261,7 +273,7 @@ LLCoros::CoroData::CoroData(CoroData* prev, const std::string& name, mPrev(prev), mName(name), // Wrap the caller's callable in our toplevel() function so we can manage - // sCurrentCoro appropriately at startup and shutdown of each coroutine. + // Current appropriately at startup and shutdown of each coroutine. mCoro(boost::bind(toplevel, _1, this, callable), stacksize), // don't consume events unless specifically directed mConsuming(false), @@ -272,13 +284,13 @@ LLCoros::CoroData::CoroData(CoroData* prev, const std::string& name, std::string LLCoros::launch(const std::string& prefix, const callable_t& callable) { std::string name(generateDistinctName(prefix)); - // pass the current value of sCurrentCoro as previous context - CoroData* newCoro = new CoroData(sCurrentCoro.get(), name, - callable, mStackSize); + Current current; + // pass the current value of Current as previous context + CoroData* newCoro = new CoroData(current, name, callable, mStackSize); // Store it in our pointer map mCoros.insert(name, newCoro); // also set it as current - sCurrentCoro.reset(newCoro); + current.reset(newCoro); /* Run the coroutine until its first wait, then return here */ (newCoro->mCoro)(std::nothrow); return name; diff --git a/indra/llcommon/llcoros.h b/indra/llcommon/llcoros.h index 39316ed0e6..93e5ea8b9f 100644 --- a/indra/llcommon/llcoros.h +++ b/indra/llcommon/llcoros.h @@ -35,6 +35,7 @@ #include <boost/ptr_container/ptr_map.hpp> #include <boost/function.hpp> #include <boost/thread/tss.hpp> +#include <boost/noncopyable.hpp> #include <string> #include <stdexcept> @@ -145,6 +146,10 @@ public: */ std::string getName() const; + /// Get an opaque, distinct token for the running coroutine (or main). + typedef void* id; + static id get_id() { return Current(); } + /// for delayed initialization void setStackSize(S32 stacksize); @@ -222,8 +227,21 @@ private: typedef boost::ptr_map<std::string, CoroData> CoroMap; CoroMap mCoros; - // identify the current coroutine's CoroData - static boost::thread_specific_ptr<LLCoros::CoroData> sCurrentCoro; + // Identify the current coroutine's CoroData. Use a little helper class so + // a caller can either use a temporary instance, or instantiate a named + // variable and access it multiple times. + class Current + { + public: + Current(); + + operator LLCoros::CoroData*() { return get(); } + LLCoros::CoroData* get() { return mCurrent->get(); } + void reset(LLCoros::CoroData* ptr) { mCurrent->reset(ptr); } + + private: + boost::thread_specific_ptr<LLCoros::CoroData>* mCurrent; + }; }; namespace llcoro @@ -231,7 +249,7 @@ namespace llcoro /// Instantiate one of these in a block surrounding any leaf point when /// control literally switches away from this coroutine. -class Suspending +class Suspending: boost::noncopyable { public: Suspending(); |