/*									tab:4 * * * "Copyright (c) 2000-2002 The Regents of the University  of California.   * All rights reserved. * * Permission to use, copy, modify, and distribute this software and its * documentation for any purpose, without fee, and without written agreement is * hereby granted, provided that the above copyright notice, the following * two paragraphs and the author appear in all copies of this software. *  * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *  * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS." * *//*									tab:4 *  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.  By *  downloading, copying, installing or using the software you agree to *  this license.  If you do not agree to this license, do not download, *  install, copy or use the software. * *  Intel Open Source License  * *  Copyright (c) 2002 Intel Corporation  *  All rights reserved.  *  Redistribution and use in source and binary forms, with or without *  modification, are permitted provided that the following conditions are *  met: *  *	Redistributions of source code must retain the above copyright *  notice, this list of conditions and the following disclaimer. *	Redistributions in binary form must reproduce the above copyright *  notice, this list of conditions and the following disclaimer in the *  documentation and/or other materials provided with the distribution. *      Neither the name of the Intel Corporation nor the names of its *  contributors may be used to endorse or promote products derived from *  this software without specific prior written permission. *   *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS *  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *  PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE INTEL OR ITS *  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, *  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, *  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *  *  *//* * Authors:   Philip Levis * History:   July 19, 2002 *	      * *//** * @author Philip Levis */includes Bombilla;module BContextSynch {  provides {    interface BombillaContextSynch as Synch;    interface BombillaAnalysis as Analysis;    interface StdControl;  }  uses {    interface BombillaError;    interface BombillaLocks as Locks;    interface BombillaInstruction as Instruction;    interface BombillaQueue as Queue;     interface BombillaStacks as Stacks;  }}implementation {  BombillaQueue readyQueue;    command result_t StdControl.init() {    call Queue.init(&readyQueue);    return SUCCESS;  }    command result_t StdControl.start() {    return SUCCESS;  }    command result_t StdControl.stop() {    return SUCCESS;  }  command void Synch.reboot() {    call Queue.init(&readyQueue);    call Locks.reboot();  }	  command bool Synch.isRunnable(BombillaContext* context) {     int8_t i;    uint16_t neededLocks = (context->acquireSet);    dbg(DBG_USR2, "VM: Checking whether context %i runnable: ", (int)context->which);    for (i = 0; i < BOMB_HEAPSIZE; i++) {      if (neededLocks & (1 << i)) {	if (call Locks.isLocked(i)) {	  dbg_clear(DBG_USR2, "no\n");	  return FALSE;	}      }    }    dbg_clear(DBG_USR2, "yes\n");    return TRUE;  }  command result_t Synch.obtainLocks(BombillaContext* caller,                                      BombillaContext* obtainer) {     int8_t i;    uint16_t neededLocks = (obtainer->acquireSet);    dbg(DBG_USR2, "VM: Attempting to obtain necessary locks for context %i\n", obtainer->which);    for (i = 0; i < BOMB_HEAPSIZE; i++) {      if (neededLocks & (1 << i)) {	call Locks.lock(obtainer, i);      }    }    obtainer->acquireSet = 0;    return SUCCESS;		  }  command result_t Synch.releaseLocks(BombillaContext* caller,                                       BombillaContext* releaser) {    int8_t i;    uint16_t lockSet = (releaser->releaseSet);    dbg(DBG_USR2, "VM: Attempting to release specified locks for context %i.\n", releaser->which);    for (i = 0; i < BOMB_HEAPSIZE; i++) {      if (lockSet & (1 << i)) {	call Locks.unlock(releaser, i);      }    }    releaser->releaseSet = 0;    return SUCCESS;		  }  command result_t Synch.releaseAllLocks(BombillaContext* caller,                                         BombillaContext* releaser) {    int8_t i;    uint16_t lockSet = (releaser->heldSet);    dbg(DBG_USR2, "VM: Attempting to release all locks for context %i.\n", releaser->which);    for (i = 0; i < BOMB_HEAPSIZE; i++) {      if (lockSet & (1 << i)) {	call Locks.unlock(releaser, i);      }    }    releaser->releaseSet = 0;    return SUCCESS;  }  command void Analysis.analyzeCapsuleVars(BombillaCapsuleBuffer* buf) {    int i;    dbg(DBG_USR2, "VM: Analyzing capsule vars for context %i: ", buf->capsule.type);    buf->usedVars = 0;    for (i = 0; i < BOMB_PGMSIZE; i++) {      if (call  Instruction.isVClass(buf->capsule.code[i])) {	uint8_t arg = (buf->capsule.code[i]) & VARG_MASK;	dbg_clear(DBG_USR2, "%i ", (int)arg);	buf->usedVars |= (1 << arg);      }    }    dbg_clear(DBG_USR2, "\n");    buf->haveSeen = 0;  } uint16_t capsuleCallsDeep(BombillaCapsuleBuffer* capsules[], int which) {    int i;    BombillaCapsuleBuffer* buf = capsules[which];    if (buf->haveSeen) {      return buf->usedVars;    }    buf->haveSeen = 1;    for (i = 0; i < BOMB_PGMSIZE; i++) {      if ((buf->capsule.code[i] & 0xfc) == OPcall0) {        uint8_t arg = (buf->capsule.code[i]) & 0x3;        buf->usedVars |= capsuleCallsDeep(capsules, arg);      }    }    return buf->usedVars; } command void Analysis.analyzeCapsuleCalls(BombillaCapsuleBuffer* capsules[]) {   int i;   int numCapsules = uniqueCount("Capsule");   for (i = 0; i < numCapsules; i++) {     capsuleCallsDeep(capsules, i);   } }  command void Synch.initializeContext(BombillaContext* context) {   context->heldSet = 0;   context->releaseSet = 0;   context->currentCapsule = &context->rootCapsule;   context->acquireSet = context->currentCapsule->usedVars;   context->pc = 0;   call Stacks.resetStacks(context);   context->queue = 0;   context->state = BOMB_STATE_HALT; } command void Synch.yieldContext(BombillaContext* context) {   BombillaContext* start = NULL;   BombillaContext* current = NULL;   dbg(DBG_USR2, "VM (%i): Yielding.\n", (int)context->which);   if (!call Queue.empty(&readyQueue)) {     do {       current = call Queue.dequeue(context, &readyQueue);       if (!call Synch.resumeContext(context, current)) {         dbg(DBG_USR2, "VM (%i): Context %i not runnable.\n", (int)context->which, (int)current->which);         if (start == NULL) {           start = current;         }         else if (start == current) {           dbg(DBG_USR2, "VM (%i): Looped on ready queue. End checks.\n", (int)context->which);           break;         }       }     }     while (!call Queue.empty(&readyQueue));   }   else {     dbg(DBG_USR2, "VM (%i): Ready queue empty.\n", (int)context->which);   } }  command bool Synch.resumeContext(BombillaContext* caller,                                  BombillaContext* context) {   context->state = BOMB_STATE_RESUMING;   if (call Synch.isRunnable(context)) {     call Synch.obtainLocks(caller, context);     signal Synch.makeRunnable(context);     dbg(DBG_USR2, "VM (%i): Resumption of %i successful.\n", (int)caller->which, (int)context->which);     return TRUE;   }   else {     dbg(DBG_USR2, "VM (%i): Resumption of %i unsuccessful, putting on the queue.\n", (int)caller->which, (int)context->which);      call Queue.enqueue(caller, &readyQueue, context);      return FALSE;    }	 } command void Synch.haltContext(BombillaContext* context) {   call Synch.releaseAllLocks(context, context);   call Synch.yieldContext(context);   context->state = BOMB_STATE_HALT;    // !!! Need something better here... it should    // dequeue a waiting context from any waiting situation    /*    if ((context->which == BOMB_CAPSULE_SEND_INDEX) &&	!call Queue.empty(&state->sendrWaitQueue)) {      BombillaContext* waiter = call Queue.dequeue(context, &state->sendrWaitQueue);      call Synch.resumeContext(context, waiter, &(state->readyQueue), state->locks);      }*/  }}