/************************************************************************
* sched/mq_initialize.c
*
* Copyright (C) 2007, 2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name NuttX 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
* COPYRIGHT OWNER OR 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.
*
************************************************************************/
/************************************************************************
* Included Files
************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <queue.h>
#include <nuttx/kmalloc.h>
#include "mq_internal.h"
/************************************************************************
* Definitions
************************************************************************/
/************************************************************************
* Private Type Declarations
************************************************************************/
/* This is a container for a list of message queue descriptors. */
struct mq_des_block_s
{
sq_entry_t queue;
struct mq_des mqdes[NUM_MSG_DESCRIPTORS];
};
/************************************************************************
* Global Variables
************************************************************************/
/* This is a list of all opened message queues */
sq_queue_t g_msgqueues;
/* The g_msgfree is a list of messages that are available for general
* use. The number of messages in this list is a system configuration
* item.
*/
sq_queue_t g_msgfree;
/* The g_msgfreeInt is a list of messages that are reserved for use by
* interrupt handlers.
*/
sq_queue_t g_msgfreeirq;
/* The g_desfree data structure is a list of message descriptors available
* to the operating system for general use. The number of messages in the
* pool is a constant.
*/
sq_queue_t g_desfree;
/************************************************************************
* Private Variables
************************************************************************/
/* g_msgalloc is a pointer to the start of the allocated block of
* messages.
*/
static mqmsg_t *g_msgalloc;
/* g_msgfreeirqalloc is a pointer to the start of the allocated block of
* messages.
*/
static mqmsg_t *g_msgfreeirqalloc;
/* g_desalloc is a list of allocated block of message queue descriptors. */
static sq_queue_t g_desalloc;
/************************************************************************
* Private Functions
************************************************************************/
/************************************************************************
* Name: mq_msgblockalloc
*
* Description:
* Allocate a block of messages and place them on the free list.
*
* Inputs Parameters:
* queue
*
************************************************************************/
static mqmsg_t *mq_msgblockalloc(sq_queue_t *queue, uint16_t nmsgs,
uint8_t alloc_type)
{
mqmsg_t *mqmsgblock;
/* The g_msgfree must be loaded at initialization time to hold the
* configured number of messages.
*/
mqmsgblock = (mqmsg_t*)kmalloc(sizeof(mqmsg_t) * nmsgs);
if (mqmsgblock)
{
mqmsg_t *mqmsg = mqmsgblock;
int i;
for (i = 0; i < nmsgs; i++)
{
mqmsg->type = alloc_type;
sq_addlast((FAR sq_entry_t*)mqmsg++, queue);
}
}
return mqmsgblock;
}
/************************************************************************
* Public Functions
************************************************************************/
/************************************************************************
* Name: mq_initialize
*
* Description:
* This function initializes the messasge system. This function must
* be called early in the initialization sequence before any of the
* other message interfaces execute.
*
* Inputs:
* None
*
* Return Value:
* None
*
************************************************************************/
void mq_initialize(void)
{
/* Initialize the list of message queues */
sq_init(&g_msgqueues);
/* Initialize the message free lists */
sq_init(&g_msgfree);
sq_init(&g_msgfreeirq);
sq_init(&g_desalloc);
/* Allocate a block of messages for general use */
g_msgalloc =
mq_msgblockalloc(&g_msgfree, CONFIG_PREALLOC_MQ_MSGS,
MQ_ALLOC_FIXED);
/* Allocate a block of messages for use exclusively by
* interrupt handlers
*/
g_msgfreeirqalloc =
mq_msgblockalloc(&g_msgfreeirq, NUM_INTERRUPT_MSGS,
MQ_ALLOC_IRQ);
/* Allocate a block of message queue descriptors */
mq_desblockalloc();
}
/************************************************************************
* Name: mq_desblockalloc
*
* Description:
* Allocate a block of message descriptors and place them on the free
* list.
*
* Inputs:
* None
*
* Return Value:
* None
*
************************************************************************/
void mq_desblockalloc(void)
{
FAR struct mq_des_block_s *mqdesblock;
/* Allocate a block of message descriptors */
mqdesblock = (FAR struct mq_des_block_s *)kmalloc(sizeof(struct mq_des_block_s));
if (mqdesblock)
{
int i;
/* Add the block to the list of allocated blocks (in case
* we ever need to reclaim the memory.
*/
sq_addlast((FAR sq_entry_t*)&mqdesblock->queue, &g_desalloc);
/* Then add each message queue descriptor to the free list */
for (i = 0; i < NUM_MSG_DESCRIPTORS; i++)
{
sq_addlast((FAR sq_entry_t*)&mqdesblock->mqdes[i], &g_desfree);
}
}
}
