Changes in src/libcfa/concurrency/coroutines.c [aed3f54:eb2e723]

File:

• src/libcfa/concurrency/coroutines.c (modified) (1 diff)

src/libcfa/concurrency/coroutines.c

@@ +1 @@
+//
+// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
+//
+// The contents of this file are covered under the licence agreement in the
+// file "LICENCE" distributed with Cforall.
+//
+// coroutines.c --
+//
+// Author           : Thierry Delisle
+// Created On       : Mon Nov 28 12:27:26 2016
+// Last Modified By : Thierry Delisle
+// 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 "coroutines"
+#include "libhdr.h"
+
+#define __CFA_INVOKE_PRIVATE__
+#include "invoke.h"
+
+//-----------------------------------------------------------------------------
+// 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
+
+//Current coroutine
+//Will need to be in TLS when multi-threading is added
+coroutine* current_coroutine;
+
+//-----------------------------------------------------------------------------
+// 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 ?{}(coStack_t* this, size_t size) {
+        this{};
+        this->size = size;
+
+        create_stack(this, this->size);
+}
+
+void ?{}(coroutine* this) {
+        this->name = "Anonymous Coroutine";
+        this->errno_ = 0;
+        this->state = Start;
+      this->notHalted = true;
+        this->starter = NULL;
+        this->last = NULL;
+}
+
+void ?{}(coroutine* this, size_t size) {
+        this{};
+        (&this->stack){size};
+}
+
+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 );
+        }
+}
+
+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);
+}
+
+// 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) {
+        LIB_DEBUG_PRINTF("Suspending back : to %p from %p\n", this_coroutine(), this_coroutine() ? this_coroutine()->last : (void*)-1);
+
+        suspend();
+}
+
+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;
+}
+
+// Local Variables: //
+// mode: c //
+// tab-width: 4 //
+// End: //