about summary refs log tree commit diff
path: root/elf/dl-tunables.list
blob: ec0fe20787605b6cdceba9ad16d705b91c3edfc6 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
# Copyright (C) 2016-2017 Free Software Foundation, Inc.
# This file is part of the GNU C Library.

# The GNU C 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.

# The GNU C 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 the GNU C Library; if not, see
# <http://www.gnu.org/licenses/>.

# Allowed attributes for tunables:
#
# type: Defaults to STRING
# minval: Optional minimum acceptable value
# maxval: Optional maximum acceptable value
# env_alias: An alias environment variable
# security_level: Specify security level of the tunable.  Valid values are:
#
# 	     SXID_ERASE: (default) Don't read for AT_SECURE binaries and
# 	     		 removed so that child processes can't read it.
# 	     SXID_IGNORE: Don't read for AT_SECURE binaries, but retained for
# 	     		  non-AT_SECURE subprocesses.
# 	     NONE: Read all the time.

glibc {
  malloc {
    check {
      type: INT_32
      minval: 0
      maxval: 3
      env_alias: MALLOC_CHECK_
    }
    top_pad {
      type: SIZE_T
      env_alias: MALLOC_TOP_PAD_
      security_level: SXID_IGNORE
    }
    perturb {
      type: INT_32
      minval: 0
      maxval: 0xff
      env_alias: MALLOC_PERTURB_
      security_level: SXID_IGNORE
    }
    mmap_threshold {
      type: SIZE_T
      env_alias: MALLOC_MMAP_THRESHOLD_
      security_level: SXID_IGNORE
    }
    trim_threshold {
      type: SIZE_T
      env_alias: MALLOC_TRIM_THRESHOLD_
      security_level: SXID_IGNORE
    }
    mmap_max {
      type: INT_32
      env_alias: MALLOC_MMAP_MAX_
      security_level: SXID_IGNORE
    }
    arena_max {
      type: SIZE_T
      env_alias: MALLOC_ARENA_MAX
      minval: 1
      security_level: SXID_IGNORE
    }
    arena_test {
      type: SIZE_T
      env_alias: MALLOC_ARENA_TEST
      minval: 1
      security_level: SXID_IGNORE
    }
    tcache_max {
      type: SIZE_T
      security_level: SXID_ERASE
    }
    tcache_count {
      type: SIZE_T
      security_level: SXID_ERASE
    }
    tcache_unsorted_limit {
      type: SIZE_T
      security_level: SXID_ERASE
    }
  }
  tune {
    hwcap_mask {
      type: UINT_64
      env_alias: LD_HWCAP_MASK
      default: HWCAP_IMPORTANT
      }
  }

  elision {
    enable {
      type: INT_32
      minval: 0
      maxval: 1
      security_level: SXID_ERASE
    }
    skip_lock_busy {
      type: INT_32
      default: 3
      security_level: SXID_ERASE
    }
    skip_lock_internal_abort {
      type: INT_32
      default: 3
      security_level: SXID_ERASE
    }
    skip_lock_after_retries {
      type: INT_32
      default: 3
      security_level: SXID_ERASE
    }
    tries {
      type: INT_32
      default: 3
      security_level: SXID_ERASE
    }
    skip_trylock_internal_abort {
      type: INT_32
      default: 3
      security_level: SXID_ERASE
    }
  }
}