| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
|---|---|
| 2 | |
| 3 | #pragma once |
| 4 | |
| 5 | #include "mos/platform/platform_defs.hpp" |
| 6 | |
| 7 | #include <mos/mos_global.h> |
| 8 | #include <mos/types.hpp> |
| 9 | |
| 10 | #define barrier() MOS_PLATFORM_MEMORY_BARRIER() |
| 11 | |
| 12 | class SpinLocker; |
| 13 | struct spinlock_t |
| 14 | { |
| 15 | bool flag = false; |
| 16 | #if MOS_DEBUG_FEATURE(spinlock) |
| 17 | const char *file = nullptr; |
| 18 | int line = 0; |
| 19 | #endif |
| 20 | |
| 21 | SpinLocker lock(); |
| 22 | }; |
| 23 | |
| 24 | #define spinlock_init(lock) \ |
| 25 | do \ |
| 26 | { \ |
| 27 | (lock)->flag = 0; \ |
| 28 | } while (0) |
| 29 | |
| 30 | // clang-format off |
| 31 | #define SPINLOCK_INIT { 0 } |
| 32 | // clang-format on |
| 33 | |
| 34 | #define _spinlock_real_acquire(lock) \ |
| 35 | do \ |
| 36 | { \ |
| 37 | barrier(); \ |
| 38 | while (__atomic_test_and_set(&(lock)->flag, __ATOMIC_ACQUIRE)) \ |
| 39 | ; \ |
| 40 | } while (0) |
| 41 | |
| 42 | #define _spinlock_real_release(lock) \ |
| 43 | do \ |
| 44 | { \ |
| 45 | __atomic_clear(&(lock)->flag, __ATOMIC_RELEASE); \ |
| 46 | } while (0) |
| 47 | |
| 48 | #if MOS_DEBUG_FEATURE(spinlock) |
| 49 | #define spinlock_acquire(lock) \ |
| 50 | do \ |
| 51 | { \ |
| 52 | _spinlock_real_acquire(lock); \ |
| 53 | (lock)->file = __FILE__; \ |
| 54 | (lock)->line = __LINE__; \ |
| 55 | } while (0) |
| 56 | #define spinlock_release(lock) \ |
| 57 | do \ |
| 58 | { \ |
| 59 | (lock)->file = NULL; \ |
| 60 | (lock)->line = 0; \ |
| 61 | _spinlock_real_release(lock); \ |
| 62 | } while (0) |
| 63 | #else |
| 64 | #define spinlock_acquire(lock) _spinlock_real_acquire(lock) |
| 65 | #define spinlock_release(lock) _spinlock_real_release(lock) |
| 66 | #endif |
| 67 | |
| 68 | #define spinlock_acquire_nodebug(lock) _spinlock_real_acquire(lock) |
| 69 | #define spinlock_release_nodebug(lock) _spinlock_real_release(lock) |
| 70 | |
| 71 | should_inline bool spinlock_is_locked(const spinlock_t *lock) |
| 72 | { |
| 73 | return lock->flag; |
| 74 | } |
| 75 | |
| 76 | typedef struct |
| 77 | { |
| 78 | spinlock_t lock; |
| 79 | void *owner; |
| 80 | size_t count; |
| 81 | } recursive_spinlock_t; |
| 82 | |
| 83 | // clang-format off |
| 84 | #define RECURSIVE_SPINLOCK_INIT { SPINLOCK_INIT, NULL, 0 } |
| 85 | // clang-format on |
| 86 | |
| 87 | should_inline void recursive_spinlock_acquire(recursive_spinlock_t *lock, void *owner) |
| 88 | { |
| 89 | if (lock->owner == owner) |
| 90 | { |
| 91 | lock->count++; |
| 92 | } |
| 93 | else |
| 94 | { |
| 95 | spinlock_acquire(&lock->lock); |
| 96 | lock->owner = owner; |
| 97 | lock->count = 1; |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | should_inline void recursive_spinlock_release(recursive_spinlock_t *lock, void *owner) |
| 102 | { |
| 103 | if (lock->owner == owner) |
| 104 | { |
| 105 | lock->count--; |
| 106 | if (lock->count == 0) |
| 107 | { |
| 108 | lock->owner = NULL; |
| 109 | spinlock_release(&lock->lock); |
| 110 | } |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | should_inline bool recursive_spinlock_is_locked(recursive_spinlock_t *lock) |
| 115 | { |
| 116 | return lock->lock.flag; |
| 117 | } |
| 118 | |
| 119 | class [[nodiscard("don't discard")]] SpinUnlocker |
| 120 | { |
| 121 | public: |
| 122 | explicit SpinUnlocker(spinlock_t *lock) : m_lock(lock) |
| 123 | { |
| 124 | spinlock_release(m_lock); |
| 125 | } |
| 126 | |
| 127 | SpinUnlocker(const SpinUnlocker &) = delete; |
| 128 | SpinUnlocker &operator=(const SpinUnlocker &) = delete; |
| 129 | SpinUnlocker(SpinUnlocker &&) = delete; |
| 130 | SpinUnlocker &operator=(SpinUnlocker &&) = delete; |
| 131 | |
| 132 | void discard() |
| 133 | { |
| 134 | m_lock = nullptr; |
| 135 | } |
| 136 | |
| 137 | ~SpinUnlocker() |
| 138 | { |
| 139 | if (m_lock) |
| 140 | spinlock_acquire(m_lock); |
| 141 | } |
| 142 | |
| 143 | private: |
| 144 | spinlock_t *m_lock; |
| 145 | }; |
| 146 | |
| 147 | class [[nodiscard("don't discard")]] SpinLocker |
| 148 | { |
| 149 | public: |
| 150 | explicit SpinLocker(spinlock_t *lock) : m_lock(lock) |
| 151 | { |
| 152 | spinlock_acquire(m_lock); |
| 153 | } |
| 154 | |
| 155 | SpinLocker(const SpinLocker &) = delete; |
| 156 | SpinLocker &operator=(const SpinLocker &) = delete; |
| 157 | SpinLocker(SpinLocker &&) = delete; |
| 158 | SpinLocker &operator=(SpinLocker &&) = delete; |
| 159 | |
| 160 | void discard() |
| 161 | { |
| 162 | m_lock = nullptr; |
| 163 | } |
| 164 | |
| 165 | ~SpinLocker() |
| 166 | { |
| 167 | if (m_lock) |
| 168 | spinlock_release(m_lock); |
| 169 | } |
| 170 | |
| 171 | SpinUnlocker UnlockTemporarily() |
| 172 | { |
| 173 | return SpinUnlocker(m_lock); |
| 174 | } |
| 175 | |
| 176 | private: |
| 177 | spinlock_t *m_lock; |
| 178 | }; |
| 179 | |
| 180 | inline SpinLocker spinlock_t::lock() |
| 181 | { |
| 182 | return SpinLocker(this); |
| 183 | } |
| 184 |