| Mathieu Desnoyers | 5b25b13 | 2015-09-11 13:07:39 -0700 | [diff] [blame^] | 1 | #ifndef _UAPI_LINUX_MEMBARRIER_H |
| 2 | #define _UAPI_LINUX_MEMBARRIER_H |
| 3 | |
| 4 | /* |
| 5 | * linux/membarrier.h |
| 6 | * |
| 7 | * membarrier system call API |
| 8 | * |
| 9 | * Copyright (c) 2010, 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 10 | * |
| 11 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 12 | * of this software and associated documentation files (the "Software"), to deal |
| 13 | * in the Software without restriction, including without limitation the rights |
| 14 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 15 | * copies of the Software, and to permit persons to whom the Software is |
| 16 | * furnished to do so, subject to the following conditions: |
| 17 | * |
| 18 | * The above copyright notice and this permission notice shall be included in |
| 19 | * all copies or substantial portions of the Software. |
| 20 | * |
| 21 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 22 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 23 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 24 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 25 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 26 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 27 | * SOFTWARE. |
| 28 | */ |
| 29 | |
| 30 | /** |
| 31 | * enum membarrier_cmd - membarrier system call command |
| 32 | * @MEMBARRIER_CMD_QUERY: Query the set of supported commands. It returns |
| 33 | * a bitmask of valid commands. |
| 34 | * @MEMBARRIER_CMD_SHARED: Execute a memory barrier on all running threads. |
| 35 | * Upon return from system call, the caller thread |
| 36 | * is ensured that all running threads have passed |
| 37 | * through a state where all memory accesses to |
| 38 | * user-space addresses match program order between |
| 39 | * entry to and return from the system call |
| 40 | * (non-running threads are de facto in such a |
| 41 | * state). This covers threads from all processes |
| 42 | * running on the system. This command returns 0. |
| 43 | * |
| 44 | * Command to be passed to the membarrier system call. The commands need to |
| 45 | * be a single bit each, except for MEMBARRIER_CMD_QUERY which is assigned to |
| 46 | * the value 0. |
| 47 | */ |
| 48 | enum membarrier_cmd { |
| 49 | MEMBARRIER_CMD_QUERY = 0, |
| 50 | MEMBARRIER_CMD_SHARED = (1 << 0), |
| 51 | }; |
| 52 | |
| 53 | #endif /* _UAPI_LINUX_MEMBARRIER_H */ |