nuttx/mm/mm_heap/mm_mallinfo.c

/****************************************************************************
 * mm/mm_heap/mm_mallinfo.c
 *
 *   Copyright (C) 2007, 2009, 2013-2014 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 <malloc.h>
#include <assert.h>
#include <debug.h>

#include <nuttx/mm/mm.h>

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: mm_mallinfo
 *
 * Description:
 *   mallinfo returns a copy of updated current heap information.
 *
 ****************************************************************************/

int mm_mallinfo(FAR struct mm_heap_s *heap, FAR struct mallinfo *info)
{
  FAR struct mm_allocnode_s *node;
#ifdef CONFIG_DEBUG_ASSERTIONS
  FAR struct mm_allocnode_s *prev;
#endif
  size_t mxordblk = 0;
  int    ordblks  = 0;  /* Number of non-inuse chunks */
  size_t uordblks = 0;  /* Total allocated space */
  size_t fordblks = 0;  /* Total non-inuse space */
#if CONFIG_MM_REGIONS > 1
  int region;
#else
# define region 0
#endif

  DEBUGASSERT(info);

  /* Visit each region */

#if CONFIG_MM_REGIONS > 1
  for (region = 0; region < heap->mm_nregions; region++)
#endif
    {
#ifdef CONFIG_DEBUG_ASSERTIONS
      prev = NULL;
#endif
      /* Visit each node in the region
       * Retake the semaphore for each region to reduce latencies
       */

      mm_takesemaphore(heap);

      for (node = heap->mm_heapstart[region];
           node < heap->mm_heapend[region];
           node = (FAR struct mm_allocnode_s *)
                  ((FAR char *)node + node->size))
        {
          minfo("region=%d node=%p size=%u preceding=%u (%c)\n",
                region, node, (unsigned int)node->size,
                (unsigned int)(node->preceding & ~MM_ALLOC_BIT),
                (node->preceding & MM_ALLOC_BIT) ? 'A' : 'F');

          /* Check if the node corresponds to an allocated memory chunk */

          if ((node->preceding & MM_ALLOC_BIT) != 0)
            {
              DEBUGASSERT(node->size >= SIZEOF_MM_ALLOCNODE);
              uordblks += node->size;
            }
          else
            {
#ifdef CONFIG_DEBUG_ASSERTIONS
              FAR struct mm_freenode_s *fnode = (FAR void *)node;
#endif
              DEBUGASSERT(node->size >= SIZEOF_MM_FREENODE);
              DEBUGASSERT(fnode->blink->flink == fnode);
              DEBUGASSERT(fnode->blink->size <= fnode->size);
              DEBUGASSERT(fnode->flink == NULL ||
                          fnode->flink->blink == fnode);
              DEBUGASSERT(fnode->flink == NULL ||
                          fnode->flink->size == 0 ||
                          fnode->flink->size >= fnode->size);
              ordblks++;
              fordblks += node->size;
              if (node->size > mxordblk)
                {
                  mxordblk = node->size;
                }
            }

          DEBUGASSERT(prev == NULL ||
                      prev->size == (node->preceding & ~MM_ALLOC_BIT));
#ifdef CONFIG_DEBUG_ASSERTIONS
          prev = node;
#endif
        }

      minfo("region=%d node=%p heapend=%p\n",
            region, node, heap->mm_heapend[region]);
      DEBUGASSERT(node == heap->mm_heapend[region]);

      mm_givesemaphore(heap);

      uordblks += SIZEOF_MM_ALLOCNODE; /* account for the tail node */
    }
#undef region

  DEBUGASSERT(uordblks + fordblks == heap->mm_heapsize);

  info->arena    = heap->mm_heapsize;
  info->ordblks  = ordblks;
  info->mxordblk = mxordblk;
  info->uordblks = uordblks;
  info->fordblks = fordblks;
  return OK;
}