To what "explicit continuation locking" do you refer?
How does this address the issue that using TSMutexLock() or MutexLock
in a currently running continuation function (unnecessarily) blocks
all other events waiting in a thread event queue? Whereas the
inability to lock a continuation mutex cause the continuation to be
requeued at the end of the thread event queue, thus allowing
succeeding events in the thread's queue to be handled.
On Tue, Oct 9, 2018 at 3:44 PM Alan Carroll
<solidwallofc...@oath.com.invalid> wrote:
>
> It's a bit more complex than that. One key thing is that if you schedule an
> event for a continuation, when the event handler is called the continuation
> mutex will be locked. Therefore it's rarely the case a plugin needs to lock
> its continuations explicitly. For that reason, simply scheduling handles
> lock contention without thread blocking.
>
> In the core, there is a class, MutexLock, which does the RAII style locking.
>
> On Tue, Oct 9, 2018 at 2:26 PM Walt Karas <wka...@oath.com.invalid> wrote:
>
> > In TS, is it important to favor use of continuation mutexes to avoid
> > thread blocking. For example, should code like this:
> >
> > before();
> > TSMutexLock(mutex);
> > critical_section();
> > TSMutexUnlock(mutex);
> > after();
> >
> > be replaced with code like:
> >
> > int contf_after(TSCont, TSEvent, void *)
> > {
> > after();
> >
> > return 0;
> > }
> >
> > int contf_critical_section(TSCont, TSEvent, void *)
> > {
> > critical_section();
> >
> > static TSCont cont_after = TSContCreate(contf_after, nullptr);
> >
> > TSContSchedule(cont_after, 0, TS_THREAD_POOL_DEFAULT);
> >
> > return 0;
> > }
> >
> > // ...
> >
> > before();
> >
> > static TSCont cont_critical_section =
> > TSContCreate(contf_critical_section, mutex);
> >
> > TSContSchedule(cont_critical_section, 0, TS_THREAD_POOL_DEFAULT);
> >
> > // ...
> >
> > (This is plugin code but I assume the same principle would apply to core
> > code.)
> >
>
>
> --
> *Beware the fisherman who's casting out his line in to a dried up riverbed.*
> *Oh don't try to tell him 'cause he won't believe. Throw some bread to the
> ducks instead.*
> *It's easier that way. *- Genesis : Duke : VI 25-28
