1  /* Malloc huge page support.  Generic implementation.
       2     Copyright (C) 2021-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public License as
       7     published by the Free Software Foundation; either version 2.1 of the
       8     License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; see the file COPYING.LIB.  If
      17     not, see <https://www.gnu.org/licenses/>.  */
      18  
      19  #ifndef _MALLOC_HUGEPAGES_H
      20  #define _MALLOC_HUGEPAGES_H
      21  
      22  #include <stddef.h>
      23  
      24  /* Return the default transparent huge page size.  */
      25  unsigned long int __malloc_default_thp_pagesize (void) attribute_hidden;
      26  
      27  enum malloc_thp_mode_t
      28  {
      29    malloc_thp_mode_always,
      30    malloc_thp_mode_madvise,
      31    malloc_thp_mode_never,
      32    malloc_thp_mode_not_supported
      33  };
      34  
      35  enum malloc_thp_mode_t __malloc_thp_mode (void) attribute_hidden;
      36  
      37  /* Return the supported huge page size from the REQUESTED sizes on PAGESIZE
      38     along with the required extra mmap flags on FLAGS,  Requesting the value
      39     of 0 returns the default huge page size, otherwise the value will be
      40     matched against the sizes supported by the system.  */
      41  void __malloc_hugepage_config (size_t requested, size_t *pagesize, int *flags)
      42       attribute_hidden;
      43  
      44  #endif /* _MALLOC_HUGEPAGES_H */