/* slice-threadinit.c - test GSlice across g_thread_init

 * Copyright (C) 2007 Tim Janik

 *

 * This work is provided "as is"; redistribution and modification

 * in whole or in part, in any medium, physical or electronic is

 * permitted without restriction.

 *

 * This work 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.

 *

 * In no event shall the authors 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.

 */

#include <glib.h>

#define N_PAGES                 (101)                   /* number of pages to sample */

#define SAMPLE_SIZE             (7)

#define PAGE_SIZE               (128)                   /* must be <= minimum GSlice alignment block */

#define MAGAZINE_PROBES         { 97, 265, 347 }        /* block sizes hopefully unused by g_thread_init */

#define MAX_PROBE_TRIALS        (1031)                  /* must be >= maximum magazine size */

#define ALIGN(size, base)       ((base) * (gsize) (((size) + (base) - 1) / (base)))

static struct {

  void *page;

  void *sample;

} pages[N_PAGES] = { { NULL, }, };

static const guint magazine_probes[] = MAGAZINE_PROBES;

#define N_MAGAZINE_PROBES       G_N_ELEMENTS (magazine_probes)

static void

release_trash_list (GSList **trash_list,

                    gsize    block_size)

{

  while (*trash_list)

    {

      g_slice_free1 (block_size, (*trash_list)->data);

      *trash_list = g_slist_delete_link (*trash_list, *trash_list);

    }

}

static GSList *free_list = NULL;

static gboolean

allocate_from_known_page (void)

{

  guint i, j, n_trials = N_PAGES * PAGE_SIZE / SAMPLE_SIZE; /* upper bound */

  for (i = 0; i < n_trials; i++)

    {

      void *b = g_slice_alloc (SAMPLE_SIZE);

      void *p = (void*) (PAGE_SIZE * ((gsize) b / PAGE_SIZE));

      free_list = g_slist_prepend (free_list, b);

      /* find page */

      for (j = 0; j < N_PAGES; j++)

        if (pages[j].page == p)

          return TRUE;

    }

  return FALSE;

}

int

main (int   argc,

      char *argv[])

{

  int j, n_pages = 0;

  void *mps[N_MAGAZINE_PROBES];

  /* probe some magazine sizes */

  for (j = 0; j < N_MAGAZINE_PROBES; j++)

    mps[j] = g_slice_alloc (magazine_probes[j]);

  /* mps[*] now contains pointers to allocated slices */

  /* allocate blocks from N_PAGES different pages */

  while (n_pages < N_PAGES)

    {

      void *b = g_slice_alloc (SAMPLE_SIZE);

      void *p = (void*) (PAGE_SIZE * ((gsize) b / PAGE_SIZE));

      for (j = 0; j < N_PAGES; j++)

        if (pages[j].page == p)

          break;

      if (j < N_PAGES)  /* known page */

        free_list = g_slist_prepend (free_list, b);

      else              /* new page */

        {

          j = n_pages++;

          pages[j].page = p;

          pages[j].sample = b;

        }

    }

  /* release intermediate allocations */

  release_trash_list (&free_list, SAMPLE_SIZE);

  /* ensure that we can allocate from known pages */

  if (!allocate_from_known_page())

    g_error ("failed to allocate from magazine/page cache (before g_thread_init)");

  /* release intermediate allocations */

  release_trash_list (&free_list, SAMPLE_SIZE);

  /* release magazine probes to be retained */

  for (j = 0; j < N_MAGAZINE_PROBES; j++)

    g_slice_free1 (magazine_probes[j], mps[j]);

  /* mps[*] now contains pointers to releaed slices */

  /* ensure probes were retained */

  for (j = 0; j < N_MAGAZINE_PROBES; j++)

    {

      GSList *trash = NULL;

      guint k;

      for (k = 0; k < MAX_PROBE_TRIALS; k++)

        {

          void *mem = g_slice_alloc (magazine_probes[j]);

          if (mem == mps[j])

            break;      /* reallocated previously freed slice */

          trash = g_slist_prepend (trash, mem);

        }

      release_trash_list (&trash, magazine_probes[j]);

      if (k >= MAX_PROBE_TRIALS)        /* failed to reallocate slice */

        g_error ("failed to reallocate slice from magazine (before g_thread_init): size=%d", magazine_probes[j]);

    }

  /* mps[*] now contains pointers to reallocated slices */

  /* release magazine probes to be retained across g_thread_init */

  for (j = 0; j < N_MAGAZINE_PROBES; j++)

    g_slice_free1 (magazine_probes[j], mps[j]);

  /* mps[*] now contains pointers to released slices */

  /* initialize threading (should retain allocator state) */

  g_thread_init (NULL);

  /* ensure probes were retained */

  for (j = 0; j < N_MAGAZINE_PROBES; j++)

    {

      GSList *trash = NULL;

      guint k;

      for (k = 0; k < MAX_PROBE_TRIALS; k++)

        {

          void *mem = g_slice_alloc (magazine_probes[j]);

          if (mem == mps[j])

            break;      /* reallocated previously freed slice */

          trash = g_slist_prepend (trash, mem);

        }

      release_trash_list (&trash, magazine_probes[j]);

      if (k >= MAX_PROBE_TRIALS)        /* failed to reallocate slice */

        g_error ("failed to reallocate slice from magazine (after g_thread_init): size=%d", magazine_probes[j]);

    }

  /* mps[*] now contains pointers to reallocated slices */

  /* ensure that we can allocate from known pages */

  if (!allocate_from_known_page())

    g_error ("failed to allocate from magazine/page cache (after g_thread_init)");

  /* some cleanups */

  for (j = 0; j < N_MAGAZINE_PROBES; j++)

    g_slice_free1 (magazine_probes[j], mps[j]);

  release_trash_list (&free_list, SAMPLE_SIZE);

  return 0;

}