Changeset 20ffcf3 for doc/proposals/concurrency/text/together.tex

Timestamp:

Nov 13, 2017, 10:45:32 AM (8 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, aaron-thesis, arm-eh, ast-experimental, cleanup-dtors, deferred_resn, demangler, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, new-env, no_list, persistent-indexer, pthread-emulation, qualifiedEnum, resolv-new, with_gc

Children:

b3ffb61

Parents:

6d2386e

Message:

Commit after new draft

File:

• doc/proposals/concurrency/text/together.tex (modified) (2 diffs)

doc/proposals/concurrency/text/together.tex

@@ -7 +7 @@
 
 \section{Threads as monitors}
-As it was subtely alluded in section \ref{threads}, \code{threads} in \CFA are in fact monitors. This means that all the monitors features are available when using threads. For example, here is a very simple two thread pipeline that could be used for a simulator of a game engine :
+As it was subtely alluded in section \ref{threads}, \code{threads} in \CFA are in fact monitors, which means that all monitor features are available when using threads. For example, here is a very simple two thread pipeline that could be used for a simulator of a game engine :
 \begin{cfacode}
 // Visualization declaration
@@ -72 +72 @@
         }
 }
+
+// Call destructor for simulator once simulator finishes
+// Call destructor for renderer to signify shutdown
 \end{cfacode}
 
 \section{Fibers \& Threads}
+As mentionned in section \ref{preemption}, \CFA uses preemptive threads by default but can use fibers on demand. Currently, using fibers is done by adding the following line of code to the program~:
+\begin{cfacode}
+unsigned int default_preemption() {
+        return 0;
+}
+\end{cfacode}
+This function is called by the kernel to fetch the default preemption rate, where 0 signifies an infinite time-slice i.e. no preemption. However, once clusters are fully implemented, it will be possible to create fibers and uthreads in on the same system :
+\begin{figure}
+\begin{cfacode}
+//Cluster forward declaration
+struct cluster;
+
+//Processor forward declaration
+struct processor;
+
+//Construct clusters with a preemption rate
+void ?{}(cluster& this, unsigned int rate);
+//Construct processor and add it to cluster
+void ?{}(processor& this, cluster& cluster);
+//Construct thread and schedule it on cluster
+void ?{}(thread& this, cluster& cluster);
+
+//Declare two clusters
+cluster thread_cluster = { 10`ms };                     //Preempt every 10 ms
+cluster fibers_cluster = { 0 };                         //Never preempt
+
+//Construct 4 processors
+processor processors[4] = {
+        //2 for the thread cluster
+        thread_cluster;
+        thread_cluster;
+        //2 for the fibers cluster
+        fibers_cluster;
+        fibers_cluster;
+};
+
+//Declares thread
+thread UThread {};
+void ?{}(UThread& this) {
+        //Construct underlying thread to automatically
+        //be scheduled on the thread cluster
+        (this){ thread_cluster }
+}
+
+void main(UThread & this);
+
+//Declares fibers
+thread Fiber {};
+void ?{}(Fiber& this) {
+        //Construct underlying thread to automatically
+        //be scheduled on the fiber cluster
+        (this.__thread){ fibers_cluster }
+}
+
+void main(Fiber & this);
+\end{cfacode}
+\end{figure}