Me@0: /*
Me@0:  * Copyright 2010  OpenSourceCodeStewardshipFoundation
Me@0:  *
Me@0:  * Licensed under BSD
Me@0:  */
Me@0: 
Me@0: #include <stdio.h>
Me@0: #include <stdlib.h>
Me@0: #include <malloc.h>
Me@0: 
Me@0: #include "VMS.h"
Me@0: #include "Queue_impl/BlockingQueue.h"
Me@0: 
Me@0: 
Me@0: /*Setup has two phases:
Me@0:  * 1) Semantic layer first calls init_VMS, which creates masterEnv, and puts
Me@0:  *    the master work-unit into the work-queue
Me@0:  * 2) Semantic layer then does its own init, which creates the initial
Me@0:  *    work-units inside the semantic layer, ready to schedule them when
Me@0:  *    asked by the first run of the masterLoop.
Me@0:  *
Me@0:  *This part is bit weird because VMS really wants to be "always there", and
Me@0:  * have applications attach and detach..  for now, this VMS is part of
Me@0:  * the app, so the VMS system starts up as part of running the app.
Me@0:  *
Me@0:  *The semantic layer is fully isolated from the VMS internasl by
Me@0:  * making the semantic layer setup into a state that it's ready with its
Me@0:  * initial work-units, ready to schedule them to slaves when the masterLoop
Me@0:  * asks.  Without this pattern, the semantic layer's setup would
Me@0:  * have to modify slaves directly to assign the initial work-units, and put
Me@0:  * them into the workQ itself, breaking the isolation completely.
Me@0:  *
Me@0:  * 
Me@0:  *The semantic layer creates the initial work-unit(s), and adds its
Me@0:  * own environment data to masterEnv, and fills in the pointers to
Me@0:  * the requestHandler and slaveScheduler plug-in functions
Me@0:  *
Me@0:  *This allocates VMS data structures, populates the master VMSProc,
Me@0:  * and master environment, and returns the master environment to the semantic
Me@0:  * layer.
Me@0:  */
Me@0:    //Global vars are all inside VMS.h
Me@0: MasterEnv *
Me@0: init_VMS(  )
Me@0:  {
Me@0:       //Make the central work-queue
Me@0:    workQ = makeQ();
Me@0: 
Me@0:    masterEnv = malloc( sizeof(MasterEnv) );
Me@0: 
Me@0:    create_master( masterEnv );
Me@0: 
Me@0:    create_slaves( masterEnv );
Me@0: 
Me@0:       //When coreLoops start up, the first thing 
Me@0:    writeQ( masterEnv->masterWorkUnit, workQ );
Me@0:  }
Me@0: 
Me@0: 
Me@0: 
Me@0: /*Fill up the virtual master data structure, which is already alloc'd in the
Me@0:  * masterEnv.
Me@0:  *The virtual Master is the same structure as a virtual slave, but it
Me@0:  * isn't in the array of virtual slaves.
Me@0:  * The reason it's the same structure is so that the coreLoop doesn't
Me@0:  *  have to differentiate -- all work units are assigned to a VMSProcr, and
Me@0:  *  the core loop treats them all the same way, whether it's the virtual
Me@0:  *  master continuation or a slave's work-unit.
Me@0:  *Note: masterLoop is jumped into an back out of, so have to be careful with
Me@0:  * register usage and saving all persistent-across-calls state to masterEnv
Me@0:  */
Me@0: void
Me@0: create_master( MasterEnv *masterEnv )
Me@0:  { VMSProcr virtMaster;
Me@0: 
Me@0:    virtMaster = &(masterEnv->virtMaster);
Me@0:    virtMaster->workUnitToDo                  = malloc( sizeof( WorkUnit ) );
Me@0:    virtMaster->workUnitToDo->workData        = masterEnv;
Me@0:       //TODO: figure out call structure: what GCC will do with regs
Me@0:       // will jump to the masterLoop from the coreLoop -- what regs need
Me@0:       // saving, from before jump to after -- and what reg to put masterEnv
Me@0:       // pointer in when jump to masterLoop
Me@0:    virtMaster->workUnitToDo->addrToJumpTo    = &masterLoop;
Me@0:    virtMaster->workUnitToDo->slaveAssignedTo = virtMaster;
Me@0:  }
Me@0: 
Me@0: void
Me@0: create_slaves( MasterEnv *masterEnv )
Me@0:  { VMSProcr *virtSlaves;
Me@0:    int i;
Me@0: 
Me@0:    virtSlaves = masterEnv->virtSlaves;  //TODO: make sure this is right
Me@0:    for( i = 0; i < NUM_SLAVES; i++ )
Me@0:     {
Me@0:          //Set state to mean "everything done, schedule work to slave"
Me@0:       virtSlaves[i].workIsDone        = FALSE;
Me@0:       virtSlaves[i].needsWorkAssigned = TRUE;
Me@0:     }
Me@0:  }
Me@0: 
Me@0: /*Semantic layer calls this when it want the system to start running..
Me@0:  *
Me@0:  *This creates the core loops, pins them to physical cores, gives them the
Me@0:  * pointer to the workQ, and starts them running.
Me@0:  */
Me@0:  void
Me@0: VMS__start()
Me@0:  { int retCode, coreIdx;
Me@0: 
Me@0: //TODO: still just skeleton code -- figure out right way to do this
Me@0: 
Me@0:       //Create the PThread loops that take from work-queue, and start them
Me@0:    for( coreIdx=0; coreIdx < NUM_WORKERS; coreIdx++ )
Me@0:     {
Me@0:       thdParams[coreIdx]        = (ThdParams *)malloc( sizeof(ThdParams) );
Me@0:       thdParams[coreIdx]->workQ = workQ;
Me@0:       thdParams[coreIdx]->id    = coreIdx;
Me@0: 
Me@0:          //Now make and start thd..  the coreLoopThds entry
Me@0:          // has all the info needed to later stop the thread.
Me@0:       retCode =
Me@0:        pthread_create( &(coreLoopThds[coreIdx]), thdAttrs, &coreLoop,
Me@0:                        (void *)(thdParams[coreIdx]) );
Me@0:       if( retCode != 0 )
Me@0:        { //error
Me@0:          printf("ERROR creating coreLoop %d, code: %d\n", coreIdx, retCode);
Me@0:          exit(-1);
Me@0:        }
Me@0: 
Me@0:       pinThdToCore( );  //figure out how to specify this..
Me@0: 
Me@0:       startThd(); //look up PThread call to start the thread running, if it's
Me@0:                   // not automatic
Me@0:     }
Me@0:  }
Me@0: 
Me@0:  /*there is a label inside this function -- save the addr of this label in
Me@0:  * the callingPr struc, as the pick-up point from which to start the next
Me@0:  * work-unit for that procr.  If turns out have to save registers, then
Me@0:  * save them in the procr struc too.  Then do assembly jump to the CoreLoop's
Me@0:  * "done with work-unit" label.  The procr struc is in the request in the
Me@0:  * slave that animated the just-ended work-unit, so all the state is saved
Me@0:  * there, and will get passed along, inside the request handler, to the
Me@0:  * next work-unit for that procr.
Me@0:  */
Me@0: VMS__save_ret_and_jump_to_CoreLoop( callingPr )
Me@0:  {
Me@0:    //TODO: figure out how to save the addr of a label into a mem loc
Me@0:    //NOTE: because resume pt is inside the VMS fn, it's always the same, no
Me@0:    // matter what the semantic layer is, no matter what semantic libr called.
Me@0:    callingPr->resumePt = &resumeNextWorkUnitPt;
Me@0:    save_processor_state_in( callingPr ); //save x86 regs, if GCC needs it to
Me@0:    coreLoopRetPt = callingPr->coreLoopRetPt;
Me@0:    //TODO: figure out how to do jump correctly -- target addr is constant
Me@0:    asm( jmp coreLoopRetPt );
Me@0: 
Me@0: resumeNextWorkUnitPt:
Me@0:    return;
Me@0:  }
Me@0: 
Me@0: 
Me@0: /*The semantic virt procr is available in the request sent from the slave
Me@0:  * 
Me@0:  * The request handler has to add the work-unit created to the semantic
Me@0:  * virtual processor the work-unit is a section of its time-line -- does this when create the
Me@0:  * work-unit -- means the procr data struc is available in the request sent
Me@0:  * from the slave, from which the new work-unit is generated..
Me@0:  */
Me@0: VMS__add_request_to_slave( SlaveReqst req, VMSProcr callingPr )
Me@0:  { VMSProcr slave;
Me@0:    slave = callingPr->workUnit->currSlave
Me@0:  req->nextRequest =  callingPr->workUnit->currSlave->requests = req;
Me@0:  }
Me@0: 
Me@0: 
Me@0: