1 #ifndef _UAPI_LINUX_MEMBARRIER_H 1 #ifndef _UAPI_LINUX_MEMBARRIER_H
2 #define _UAPI_LINUX_MEMBARRIER_H 2 #define _UAPI_LINUX_MEMBARRIER_H
3 3
4 /* 4 /*
5 * linux/membarrier.h 5 * linux/membarrier.h
6 * 6 *
7 * membarrier system call API 7 * membarrier system call API
8 * 8 *
9 * Copyright (c) 2010, 2015 Mathieu Desnoyers 9 * Copyright (c) 2010, 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
10 * 10 *
11 * Permission is hereby granted, free of charg 11 * Permission is hereby granted, free of charge, to any person obtaining a copy
12 * of this software and associated documentati 12 * of this software and associated documentation files (the "Software"), to deal
13 * in the Software without restriction, includ 13 * in the Software without restriction, including without limitation the rights
14 * to use, copy, modify, merge, publish, distr 14 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
15 * copies of the Software, and to permit perso 15 * copies of the Software, and to permit persons to whom the Software is
16 * furnished to do so, subject to the followin 16 * furnished to do so, subject to the following conditions:
17 * 17 *
18 * The above copyright notice and this permiss 18 * The above copyright notice and this permission notice shall be included in
19 * all copies or substantial portions of the S 19 * all copies or substantial portions of the Software.
20 * 20 *
21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT W 21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
22 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE W 22 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINF 23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
24 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR 24 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
25 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT 25 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
26 * OUT OF OR IN CONNECTION WITH THE SOFTWARE O 26 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
27 * SOFTWARE. 27 * SOFTWARE.
28 */ 28 */
29 29
30 /** 30 /**
31 * enum membarrier_cmd - membarrier system cal 31 * enum membarrier_cmd - membarrier system call command
32 * @MEMBARRIER_CMD_QUERY: Query the set of s 32 * @MEMBARRIER_CMD_QUERY: Query the set of supported commands. It returns
33 * a bitmask of valid 33 * a bitmask of valid commands.
34 * @MEMBARRIER_CMD_GLOBAL: Execute a memory b !! 34 * @MEMBARRIER_CMD_SHARED: Execute a memory barrier on all running threads.
35 * Upon return from s 35 * Upon return from system call, the caller thread
36 * is ensured that al 36 * is ensured that all running threads have passed
37 * through a state wh 37 * through a state where all memory accesses to
38 * user-space address 38 * user-space addresses match program order between
39 * entry to and retur 39 * entry to and return from the system call
40 * (non-running threa 40 * (non-running threads are de facto in such a
41 * state). This cover 41 * state). This covers threads from all processes
42 * running on the sys 42 * running on the system. This command returns 0.
43 * @MEMBARRIER_CMD_GLOBAL_EXPEDITED: <<
44 * Execute a memory b <<
45 * of all processes w <<
46 * with MEMBARRIER_CM <<
47 * Upon return from s <<
48 * is ensured that al <<
49 * through a state wh <<
50 * user-space address <<
51 * entry to and retur <<
52 * (non-running threa <<
53 * state). This only <<
54 * which registered w <<
55 * MEMBARRIER_CMD_REG <<
56 * This command retur <<
57 * registration is ab <<
58 * the barriers, it i <<
59 * MEMBARRIER_CMD_GLO <<
60 * non-registered pro <<
61 * @MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED: <<
62 * Register the proce <<
63 * MEMBARRIER_CMD_GLO <<
64 * barriers. Always r <<
65 * @MEMBARRIER_CMD_PRIVATE_EXPEDITED: 43 * @MEMBARRIER_CMD_PRIVATE_EXPEDITED:
66 * Execute a memory b 44 * Execute a memory barrier on each running
67 * thread belonging t 45 * thread belonging to the same process as the current
68 * thread. Upon retur 46 * thread. Upon return from system call, the
69 * caller thread is e 47 * caller thread is ensured that all its running
70 * threads siblings h 48 * threads siblings have passed through a state
71 * where all memory a 49 * where all memory accesses to user-space
72 * addresses match pr 50 * addresses match program order between entry
73 * to and return from 51 * to and return from the system call
74 * (non-running threa 52 * (non-running threads are de facto in such a
75 * state). This only 53 * state). This only covers threads from the
76 * same process as th !! 54 * same processes as the caller thread. This
77 * command returns 0 55 * command returns 0 on success. The
78 * "expedited" comman 56 * "expedited" commands complete faster than
79 * the non-expedited 57 * the non-expedited ones, they never block,
80 * but have the downs 58 * but have the downside of causing extra
81 * overhead. A proces 59 * overhead. A process needs to register its
82 * intent to use the 60 * intent to use the private expedited command
83 * prior to using it, 61 * prior to using it, otherwise this command
84 * returns -EPERM. 62 * returns -EPERM.
85 * @MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED: 63 * @MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED:
86 * Register the proce 64 * Register the process intent to use
87 * MEMBARRIER_CMD_PRI 65 * MEMBARRIER_CMD_PRIVATE_EXPEDITED. Always
88 * returns 0. 66 * returns 0.
89 * @MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE <<
90 * In addition to pro <<
91 * guarantees describ <<
92 * MEMBARRIER_CMD_PRI <<
93 * the caller thread, <<
94 * call, that all its <<
95 * have executed a co <<
96 * instruction. (arch <<
97 * guarantee that non <<
98 * core serializing i <<
99 * resume user-space <<
100 * covers threads fro <<
101 * caller thread. Thi <<
102 * success. The "expe <<
103 * faster than the no <<
104 * never block, but h <<
105 * causing extra over <<
106 * not implemented by <<
107 * is returned. A pro <<
108 * intent to use the <<
109 * core command prior <<
110 * this command retur <<
111 * @MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_ <<
112 * Register the proce <<
113 * MEMBARRIER_CMD_PRI <<
114 * If this command is <<
115 * architecture, -EIN <<
116 * Returns 0 on succe <<
117 * @MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ: <<
118 * Ensure the caller <<
119 * system call, that <<
120 * siblings have any <<
121 * critical sections <<
122 * parameter is 0; if <<
123 * MEMBARRIER_CMD_FLA <<
124 * then this operatio <<
125 * on CPU indicated b <<
126 * not implemented by <<
127 * is returned. A pro <<
128 * intent to use the <<
129 * command prior to u <<
130 * this command retur <<
131 * @MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_ <<
132 * Register the proce <<
133 * MEMBARRIER_CMD_PRI <<
134 * If this command is <<
135 * architecture, -EIN <<
136 * Returns 0 on succe <<
137 * @MEMBARRIER_CMD_SHARED: <<
138 * Alias to MEMBARRIE <<
139 * header backward co <<
140 * @MEMBARRIER_CMD_GET_REGISTRATIONS: <<
141 * Returns a bitmask <<
142 * registration comma <<
143 * 67 *
144 * Command to be passed to the membarrier syst 68 * Command to be passed to the membarrier system call. The commands need to
145 * be a single bit each, except for MEMBARRIER 69 * be a single bit each, except for MEMBARRIER_CMD_QUERY which is assigned to
146 * the value 0. 70 * the value 0.
147 */ 71 */
148 enum membarrier_cmd { 72 enum membarrier_cmd {
149 MEMBARRIER_CMD_QUERY !! 73 MEMBARRIER_CMD_QUERY = 0,
150 MEMBARRIER_CMD_GLOBAL !! 74 MEMBARRIER_CMD_SHARED = (1 << 0),
151 MEMBARRIER_CMD_GLOBAL_EXPEDITED !! 75 /* reserved for MEMBARRIER_CMD_SHARED_EXPEDITED (1 << 1) */
152 MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDIT !! 76 /* reserved for MEMBARRIER_CMD_PRIVATE (1 << 2) */
153 MEMBARRIER_CMD_PRIVATE_EXPEDITED !! 77 MEMBARRIER_CMD_PRIVATE_EXPEDITED = (1 << 3),
154 MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDI !! 78 MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED = (1 << 4),
155 MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_ <<
156 MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDI <<
157 MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ <<
158 MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDI <<
159 MEMBARRIER_CMD_GET_REGISTRATIONS <<
160 <<
161 /* Alias for header backward compatibi <<
162 MEMBARRIER_CMD_SHARED <<
163 }; <<
164 <<
165 enum membarrier_cmd_flag { <<
166 MEMBARRIER_CMD_FLAG_CPU = (1 < <<
167 }; 79 };
168 80
169 #endif /* _UAPI_LINUX_MEMBARRIER_H */ 81 #endif /* _UAPI_LINUX_MEMBARRIER_H */
170 82
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.