sysdeps/generic/malloc-hugepages.h

   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 */