/* GLIB sliced memory - fast threaded memory chunk allocator

 * Copyright (C) 2005 Tim Janik

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, see <http://www.gnu.org/licenses/>.

 */

#include <glib.h>

#include <string.h>

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

static gdouble parse_memsize (const gchar *cstring);

static void    usage         (void);

static void

fill_memory (guint **mem,

             guint   n,

             guint   val)

{

  guint j, o = 0;

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

    mem[j][o] = val;

}

static guint64

access_memory3 (guint  **mema,

                guint  **memb,

                guint  **memd,

                guint    n,

                guint64  repeats)

{

  guint64 accu = 0, i, j;

  const guint o = 0;

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

    {

      for (j = 1; j < n; j += 2)

        memd[j][o] = mema[j][o] + memb[j][o];

    }

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

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

      accu += memd[j][o];

  return accu;

}

static void

touch_mem (guint64 block_size,

           guint64 n_blocks,

           guint64 repeats)

{

  guint64 j, accu, n = n_blocks;

  GTimer *timer;

  guint **memc;

  guint **memb;

  guint **mema = g_new (guint*, n);

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

    mema[j] = g_slice_alloc (block_size);

  memb = g_new (guint*, n);

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

    memb[j] = g_slice_alloc (block_size);

  memc = g_new (guint*, n);

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

    memc[j] = g_slice_alloc (block_size);

  timer = g_timer_new();

  fill_memory (mema, n, 2);

  fill_memory (memb, n, 3);

  fill_memory (memc, n, 4);

  access_memory3 (mema, memb, memc, n, 3);

  g_timer_start (timer);

  accu = access_memory3 (mema, memb, memc, n, repeats);

  g_timer_stop (timer);

  g_print ("Access-time = %fs\n", g_timer_elapsed (timer, NULL));

  g_assert (accu / repeats == (2 + 3) * n / 2 + 4 * n / 2);

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

    {

      g_slice_free1 (block_size, mema[j]);

      g_slice_free1 (block_size, memb[j]);

      g_slice_free1 (block_size, memc[j]);

    }

  g_timer_destroy (timer);

  g_free (mema);

  g_free (memb);

  g_free (memc);

}

static void

usage (void)

{

  g_print ("Usage: slice-color <block-size> [memory-size] [repeats] [colorization]\n");

}

int

main (int   argc,

      char *argv[])

{

  guint64 block_size = 512, area_size = 1024 * 1024, n_blocks, repeats = 1000000;

  if (argc > 1)

    block_size = parse_memsize (argv[1]);

  else

    {

      usage();

      block_size = 512;

    }

  if (argc > 2)

    area_size = parse_memsize (argv[2]);

  if (argc > 3)

    repeats = parse_memsize (argv[3]);

  if (argc > 4)

    g_slice_set_config (G_SLICE_CONFIG_COLOR_INCREMENT, parse_memsize (argv[4]));

  /* figure number of blocks from block and area size.

   * divide area by 3 because touch_mem() allocates 3 areas

   */

  n_blocks = area_size / 3 / ALIGN (block_size, sizeof (gsize) * 2);

  /* basic sanity checks */

  if (!block_size || !n_blocks || block_size >= area_size)

    {

      g_printerr ("Invalid arguments: block-size=%" G_GUINT64_FORMAT " memory-size=%" G_GUINT64_FORMAT "\n", block_size, area_size);

      usage();

      return 1;

    }

  g_printerr ("Will allocate and touch %" G_GUINT64_FORMAT " blocks of %" G_GUINT64_FORMAT " bytes (= %" G_GUINT64_FORMAT " bytes) %" G_GUINT64_FORMAT " times with color increment: 0x%08" G_GINT64_MODIFIER "x\n",

              n_blocks, block_size, n_blocks * block_size, repeats,

	      (guint64)g_slice_get_config (G_SLICE_CONFIG_COLOR_INCREMENT));

  touch_mem (block_size, n_blocks, repeats);

  return 0;

}

static gdouble

parse_memsize (const gchar *cstring)

{

  gchar *mem = g_strdup (cstring);

  gchar *string = g_strstrip (mem);

  guint l = strlen (string);

  gdouble f = 0;

  gchar *derr = NULL;

  gdouble msize;

  switch (l ? string[l - 1] : 0)

    {

    case 'k':   f = 1000;               break;

    case 'K':   f = 1024;               break;

    case 'm':   f = 1000000;            break;

    case 'M':   f = 1024 * 1024;        break;

    case 'g':   f = 1000000000;         break;

    case 'G':   f = 1024 * 1024 * 1024; break;

    }

  if (f)

    string[l - 1] = 0;

  msize = g_ascii_strtod (string, &derr);

  g_free (mem);

  if (derr && *derr)

    {

      g_printerr ("failed to parse number at: %s\n", derr);

      msize = 0;

    }

  if (f)

    msize *= f;

  return msize;

}