projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| a33fda35 WL |
1 | /* |
| 2 | * Queued spinlock | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or modify | |
| 5 | * it under the terms of the GNU General Public License as published by | |
| 6 | * the Free Software Foundation; either version 2 of the License, or | |
| 7 | * (at your option) any later version. | |
| 8 | * | |
| 9 | * This program is distributed in the hope that it will be useful, | |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 12 | * GNU General Public License for more details. | |
| 13 | * | |
| 14 | * (C) Copyright 2013-2015 Hewlett-Packard Development Company, L.P. | |
| 15 | * | |
| 16 | * Authors: Waiman Long <waiman.long@hp.com> | |
| 17 | */ | |
| 18 | #ifndef __ASM_GENERIC_QSPINLOCK_TYPES_H | |
| 19 | #define __ASM_GENERIC_QSPINLOCK_TYPES_H | |
| 20 | ||
| 21 | /* | |
| 22 | * Including atomic.h with PARAVIRT on will cause compilation errors because | |
| 23 | * of recursive header file incluson via paravirt_types.h. So don't include | |
| 24 | * it if PARAVIRT is on. | |
| 25 | */ | |
| 26 | #ifndef CONFIG_PARAVIRT | |
| 27 | #include <linux/types.h> | |
| 28 | #include <linux/atomic.h> | |
| 29 | #endif | |
| 30 | ||
| 31 | typedef struct qspinlock { | |
| 32 | atomic_t val; | |
| 33 | } arch_spinlock_t; | |
| 34 | ||
| 35 | /* | |
| 36 | * Bitfields in the atomic value: | |
| 37 | * | |
| 69f9cae9 PZI |
38 | * When NR_CPUS < 16K |
| 39 | * 0- 7: locked byte | |
| 40 | * 8: pending | |
| 41 | * 9-15: not used | |
| 42 | * 16-17: tail index | |
| 43 | * 18-31: tail cpu (+1) | |
| 44 | * | |
| 45 | * When NR_CPUS >= 16K | |
| a33fda35 | 46 | * 0- 7: locked byte |
| c1fb159d PZI |
47 | * 8: pending |
| 48 | * 9-10: tail index | |
| 49 | * 11-31: tail cpu (+1) | |
| a33fda35 WL |
50 | */ |
| 51 | #define _Q_SET_MASK(type) (((1U << _Q_ ## type ## _BITS) - 1)\ | |
| 52 | << _Q_ ## type ## _OFFSET) | |
| 53 | #define _Q_LOCKED_OFFSET 0 | |
| 54 | #define _Q_LOCKED_BITS 8 | |
| 55 | #define _Q_LOCKED_MASK _Q_SET_MASK(LOCKED) | |
| 56 | ||
| c1fb159d | 57 | #define _Q_PENDING_OFFSET (_Q_LOCKED_OFFSET + _Q_LOCKED_BITS) |
| 69f9cae9 PZI |
58 | #if CONFIG_NR_CPUS < (1U << 14) |
| 59 | #define _Q_PENDING_BITS 8 | |
| 60 | #else | |
| c1fb159d | 61 | #define _Q_PENDING_BITS 1 |
| 69f9cae9 | 62 | #endif |
| c1fb159d PZI |
63 | #define _Q_PENDING_MASK _Q_SET_MASK(PENDING) |
| 64 | ||
| 65 | #define _Q_TAIL_IDX_OFFSET (_Q_PENDING_OFFSET + _Q_PENDING_BITS) | |
| a33fda35 WL |
66 | #define _Q_TAIL_IDX_BITS 2 |
| 67 | #define _Q_TAIL_IDX_MASK _Q_SET_MASK(TAIL_IDX) | |
| 68 | ||
| 69 | #define _Q_TAIL_CPU_OFFSET (_Q_TAIL_IDX_OFFSET + _Q_TAIL_IDX_BITS) | |
| 70 | #define _Q_TAIL_CPU_BITS (32 - _Q_TAIL_CPU_OFFSET) | |
| 71 | #define _Q_TAIL_CPU_MASK _Q_SET_MASK(TAIL_CPU) | |
| 72 | ||
| 69f9cae9 | 73 | #define _Q_TAIL_OFFSET _Q_TAIL_IDX_OFFSET |
| 6403bd7d WL |
74 | #define _Q_TAIL_MASK (_Q_TAIL_IDX_MASK | _Q_TAIL_CPU_MASK) |
| 75 | ||
| a33fda35 | 76 | #define _Q_LOCKED_VAL (1U << _Q_LOCKED_OFFSET) |
| c1fb159d | 77 | #define _Q_PENDING_VAL (1U << _Q_PENDING_OFFSET) |
| a33fda35 WL |
78 | |
| 79 | #endif /* __ASM_GENERIC_QSPINLOCK_TYPES_H */ |