/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/**
 * @page article_atomic Invoking multiple primitives as a single atomic operation
 * It is often necessary to invoke multiple operations involving a
 * reschedulation as a single atomic operation.<br>
 * ChibiOS/RT already implements APIs that perform complex operations, as
 * example the API @p chSemSignalWait() performs two operations atomically.<br>
 * If more complex operations are required in your application then it is
 * possible to build macro-operations, see the following example:
 * @code
  chSysLock();
 
  chSemSignalI(&sem1);
  chSemSignalI(&sem2);
  chMtxUnlockS();
  chSchRescheduleS();
 
  chSysUnlock();
 * @endcode
 * The above example performs a signal operation on two semaphores, unlocks the
 * last aquired mutex and finally performs a reschedulation. All the operations
 * are performed atomically.<br>
 * An hypotetical @p chSemSignalSignalWait() operation could be implemented as
 * follow:
 * @code
  chSysLock();
 
  chSemSignalI(&sem1);
  chSemSignalI(&sem2);
  chSemWaitS(&Sem3);  /* May reschedule or not. */
  chSchRescheduleS(); /* This one reschedules if necessary. */
 
  chSysUnlock();
 * @endcode
 * In general multiple @ref I-Class and (non rescheduling) @ref S-Class APIs
 * can be included and the block is terminated by a rescheduling @ref S-Class
 * API. An extra @p chSchRescheduleS() can be present at the very end of the
 * block, it only reschedules if a reschedulation is still required.
 */