Changes in src/libcfa/concurrency/threads.c [c84e80a:596f987b]

File:

• src/libcfa/concurrency/threads.c (modified) (3 diffs)

src/libcfa/concurrency/threads.c

@@ -1 @@
-//                              -*- Mode: CFA -*-
 //
 // Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
@@ -9 +8 @@
 //
 // Author           : Thierry Delisle
-// Created On       : Tue Jan 17 12:27:26 2016
+// Created On       : Mon Nov 28 12:27:26 2016
 // Last Modified By : Thierry Delisle
-// Last Modified On : --
+// Last Modified On : Mon Nov 28 12:27:26 2016
 // Update Count     : 0
 //
 
+extern "C" {
+#include <stddef.h>
+#include <malloc.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/mman.h>
+}
+
 #include "threads"
-
-#include "kernel"
 #include "libhdr.h"
 
@@ -23 +29 @@
 #include "invoke.h"
 
-#include <stdlib>
+//-----------------------------------------------------------------------------
+// Global state variables
+
+// minimum feasible stack size in bytes
+#define MinStackSize 1000
+static size_t pageSize = 0;                             // architecture pagesize HACK, should go in proper runtime singleton
+
+//Extra private desctructor for the main
+//FIXME the main should not actually allocate a stack
+//Since the main is never resumed the extra stack does not cause 
+//any problem but it is wasted memory
+void ?{}(coStack_t* this, size_t size);
+void ?{}(coroutine* this, size_t size);
+
+//Main coroutine
+//FIXME do not construct a stack for the main
+coroutine main_coroutine = { 1000 };
+
+//Current coroutine
+//Will need to be in TLS when multi-threading is added
+coroutine* current_coroutine = &main_coroutine;
 
 //-----------------------------------------------------------------------------
-// Forward declarations
-forall(otype T | is_thread(T) )
-void start( thread(T)* this );
-
-forall(otype T | is_thread(T) )
-void stop( thread(T)* this );
-
-//-----------------------------------------------------------------------------
-// Thread ctors and dtors
-
-void ?{}(thread_h* this) {
-        (&this->c){};
+// Coroutine ctors and dtors
+void ?{}(coStack_t* this) {
+        this->size              = 10240;        // size of stack
+        this->storage   = NULL; // pointer to stack
+        this->limit             = NULL; // stack grows towards stack limit
+        this->base              = NULL; // base of stack
+        this->context   = NULL; // address of cfa_context_t
+        this->top               = NULL; // address of top of storage
+        this->userStack = false;        
 }
 
-void ^?{}(thread_h* this) {
-        ^(&this->c){};
+void ?{}(coStack_t* this, size_t size) {
+        this{};
+        this->size = size;
+
+        create_stack(this, this->size);
 }
 
-forall(otype T | is_thread(T) )
-void ?{}( thread(T)* this ) {
-        printf("thread() ctor\n");
-        (&this->handle){};
-        start(this);
+void ?{}(coroutine* this) {
+        this->name = "Anonymous Coroutine";
+        this->errno_ = 0;
+        this->state = Start;
+      this->notHalted = true;
+        this->starter = NULL;
+        this->last = NULL;
 }
 
-forall(otype T, ttype P | is_thread(T) | { void ?{}(T*, P); } )
-void ?{}( thread(T)* this, P params ) {
-        (&this->handle){ params };
-        start(this);
+void ?{}(coroutine* this, size_t size) {
+        this{};
+        (&this->stack){size};
 }
 
-forall(otype T | is_thread(T) )
-void ^?{}( thread(T)* this ) {
-        stop(this);
-        ^(&this->handle){};
+void ^?{}(coStack_t* this) {
+        if ( ! this->userStack ) {
+                LIB_DEBUG_DO(
+                        if ( mprotect( this->storage, pageSize, PROT_READ | PROT_WRITE ) == -1 ) {
+                                abortf( "(coStack_t *)%p.^?{}() : internal error, mprotect failure, error(%d) %s.", this, errno, strerror( errno ) );
+                        }
+                );
+                free( this->storage );
+        }
 }
 
-//-----------------------------------------------------------------------------
-// Starting and stopping threads
-extern "C" {
-      forall(dtype T | is_thread(T))
-      void CtxInvokeThread(T * this);
+void ^?{}(coroutine* this) {}
+
+// Part of the Public API
+// Not inline since only ever called once per coroutine
+forall(dtype T | is_coroutine(T))
+void prime(T* cor) {
+        coroutine* this = get_coroutine(cor);
+        assert(this->state == Start);
+
+        this->state = Primed;
+        resume(cor);
 }
 
-forall(otype T | is_thread(T))
-void start( thread(T)* this ) {
-        T* handle  = &this->handle;
-        coroutine* thrd_c = get_coroutine(handle);
-        thread_h*  thrd_h = get_thread   (handle);
-        thrd_c->last = this_coroutine();
-        current_coroutine = thrd_c;
-
-        // LIB_DEBUG_PRINTF("Thread start : %p (t %p, c %p)\n", handle, thrd_c, thrd_h);
-
-        create_stack(&thrd_c->stack, thrd_c->stack.size);
-        CtxStart(handle, CtxInvokeThread);
-        CtxSwitch( thrd_c->last->stack.context, thrd_c->stack.context );
-
-        scheduler_add(thrd_h);
+// We need to call suspend from invoke.c, so we expose this wrapper that
+// is not inline (We can't inline Cforall in C)
+void suspend_no_inline(void) {
+        suspend();
 }
 
-forall(otype T | is_thread(T) )
-void stop( thread(T)* this ) {
+void corCxtSw(coroutine* src, coroutine* dst) {
+        // THREAD_GETMEM( This )->disableInterrupts();
 
+        // set state of current coroutine to inactive
+        src->state = Inactive;
+
+        // set new coroutine that task is executing
+        current_coroutine = dst;                        
+
+        // context switch to specified coroutine
+        CtxSwitch( src->stack.context, dst->stack.context );
+        // when CtxSwitch returns we are back in the src coroutine              
+
+        // set state of new coroutine to active
+        src->state = Active;
+
+        // THREAD_GETMEM( This )->enableInterrupts();
+} //ctxSwitchDirect
+
+void create_stack( coStack_t* this, unsigned int storageSize ) {
+        //TEMP HACK do this on proper kernel startup
+        if(pageSize == 0ul) pageSize = sysconf( _SC_PAGESIZE );
+
+        size_t cxtSize = libCeiling( sizeof(machine_context_t), 8 ); // minimum alignment
+
+        if ( (intptr_t)this->storage == 0 ) {
+                this->userStack = false;
+                this->size = libCeiling( storageSize, 16 );
+                // use malloc/memalign because "new" raises an exception for out-of-memory
+                
+                // assume malloc has 8 byte alignment so add 8 to allow rounding up to 16 byte alignment
+                LIB_DEBUG_DO( this->storage = memalign( pageSize, cxtSize + this->size + pageSize ) );
+                LIB_NO_DEBUG_DO( this->storage = malloc( cxtSize + this->size + 8 ) );
+
+                LIB_DEBUG_DO(
+                        if ( mprotect( this->storage, pageSize, PROT_NONE ) == -1 ) {
+                                abortf( "(uMachContext &)%p.createContext() : internal error, mprotect failure, error(%d) %s.", this, (int)errno, strerror( (int)errno ) );
+                        } // if
+                );
+
+                if ( (intptr_t)this->storage == 0 ) {
+                        abortf( "Attempt to allocate %d bytes of storage for coroutine or task execution-state but insufficient memory available.", this->size );
+                } // if
+
+                LIB_DEBUG_DO( this->limit = (char *)this->storage + pageSize );
+                LIB_NO_DEBUG_DO( this->limit = (char *)libCeiling( (unsigned long)this->storage, 16 ) ); // minimum alignment
+
+        } else {
+                assertf( ((size_t)this->storage & (libAlign() - 1)) != 0ul, "Stack storage %p for task/coroutine must be aligned on %d byte boundary.", this->storage, (int)libAlign() );
+                this->userStack = true;
+                this->size = storageSize - cxtSize;
+
+                if ( this->size % 16 != 0u ) this->size -= 8;
+
+                this->limit = (char *)libCeiling( (unsigned long)this->storage, 16 ); // minimum alignment
+        } // if
+        assertf( this->size >= MinStackSize, "Stack size %d provides less than minimum of %d bytes for a stack.", this->size, MinStackSize );
+
+        this->base = (char *)this->limit + this->size;
+        this->context = this->base;
+        this->top = (char *)this->context + cxtSize;
 }