1 /*
2 * Copyright (c) 2006-2023, RT-Thread Development Team
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 *
6 * Change Logs:
7 * Date Author Notes
8 * 2018-10-30 Bernard The first version
9 * 2023-09-15 xqyjlj perf rt_hw_interrupt_disable/enable
10 * 2023-12-10 xqyjlj spinlock should lock sched
11 * 2024-01-25 Shell Using rt_exit_critical_safe
12 */
13 #include <rthw.h>
14 #include <rtthread.h>
15
16 #ifdef RT_USING_SMART
17 #include <lwp.h>
18 #endif
19
20 #ifdef RT_USING_DEBUG
21 rt_base_t _cpus_critical_level;
22 #endif /* RT_USING_DEBUG */
23
24 static struct rt_cpu _cpus[RT_CPUS_NR];
25 rt_hw_spinlock_t _cpus_lock;
26 #if defined(RT_DEBUGING_SPINLOCK)
27 void *_cpus_lock_owner = 0;
28 void *_cpus_lock_pc = 0;
29
30 #endif /* RT_DEBUGING_SPINLOCK */
31
32 /**
33 * @brief Initialize a static spinlock object.
34 *
35 * @param lock is a pointer to the spinlock to initialize.
36 */
rt_spin_lock_init(struct rt_spinlock * lock)37 void rt_spin_lock_init(struct rt_spinlock *lock)
38 {
39 rt_hw_spin_lock_init(&lock->lock);
40 }
RTM_EXPORT(rt_spin_lock_init)41 RTM_EXPORT(rt_spin_lock_init)
42
43 /**
44 * @brief This function will lock the spinlock, will lock the thread scheduler.
45 *
46 * @note If the spinlock is locked, the current CPU will keep polling the spinlock state
47 * until the spinlock is unlocked.
48 *
49 * @param lock is a pointer to the spinlock.
50 */
51 void rt_spin_lock(struct rt_spinlock *lock)
52 {
53 rt_enter_critical();
54 rt_hw_spin_lock(&lock->lock);
55 RT_SPIN_LOCK_DEBUG(lock);
56 }
RTM_EXPORT(rt_spin_lock)57 RTM_EXPORT(rt_spin_lock)
58
59 /**
60 * @brief This function will unlock the spinlock, will unlock the thread scheduler.
61 *
62 * @note If the scheduling function is called before unlocking, it will be scheduled in this function.
63 *
64 * @param lock is a pointer to the spinlock.
65 */
66 void rt_spin_unlock(struct rt_spinlock *lock)
67 {
68 rt_base_t critical_level;
69 RT_SPIN_UNLOCK_DEBUG(lock, critical_level);
70 rt_hw_spin_unlock(&lock->lock);
71 rt_exit_critical_safe(critical_level);
72 }
RTM_EXPORT(rt_spin_unlock)73 RTM_EXPORT(rt_spin_unlock)
74
75 /**
76 * @brief This function will disable the local interrupt and then lock the spinlock, will lock the thread scheduler.
77 *
78 * @note If the spinlock is locked, the current CPU will keep polling the spinlock state
79 * until the spinlock is unlocked.
80 *
81 * @param lock is a pointer to the spinlock.
82 *
83 * @return Return current cpu interrupt status.
84 */
85 rt_base_t rt_spin_lock_irqsave(struct rt_spinlock *lock)
86 {
87 rt_base_t level;
88
89 level = rt_hw_local_irq_disable();
90 rt_enter_critical();
91 rt_hw_spin_lock(&lock->lock);
92 RT_SPIN_LOCK_DEBUG(lock);
93 return level;
94 }
RTM_EXPORT(rt_spin_lock_irqsave)95 RTM_EXPORT(rt_spin_lock_irqsave)
96
97 /**
98 * @brief This function will unlock the spinlock and then restore current cpu interrupt status, will unlock the thread scheduler.
99 *
100 * @note If the scheduling function is called before unlocking, it will be scheduled in this function.
101 *
102 * @param lock is a pointer to the spinlock.
103 *
104 * @param level is interrupt status returned by rt_spin_lock_irqsave().
105 */
106 void rt_spin_unlock_irqrestore(struct rt_spinlock *lock, rt_base_t level)
107 {
108 rt_base_t critical_level;
109
110 RT_SPIN_UNLOCK_DEBUG(lock, critical_level);
111 rt_hw_spin_unlock(&lock->lock);
112 rt_exit_critical_safe(critical_level);
113 rt_hw_local_irq_enable(level);
114 }
RTM_EXPORT(rt_spin_unlock_irqrestore)115 RTM_EXPORT(rt_spin_unlock_irqrestore)
116
117 /**
118 * @brief This fucntion will return current cpu object.
119 *
120 * @return Return a pointer to the current cpu object.
121 */
122 struct rt_cpu *rt_cpu_self(void)
123 {
124 return &_cpus[rt_hw_cpu_id()];
125 }
126
127 /**
128 * @brief This fucntion will return the cpu object corresponding to index.
129 *
130 * @param index is the index of target cpu object.
131 *
132 * @return Return a pointer to the cpu object corresponding to index.
133 */
rt_cpu_index(int index)134 struct rt_cpu *rt_cpu_index(int index)
135 {
136 return &_cpus[index];
137 }
138
139 /**
140 * @brief This function will lock all cpus's scheduler and disable local irq.
141 *
142 * @return Return current cpu interrupt status.
143 */
rt_cpus_lock(void)144 rt_base_t rt_cpus_lock(void)
145 {
146 rt_base_t level;
147 struct rt_cpu* pcpu;
148
149 level = rt_hw_local_irq_disable();
150 pcpu = rt_cpu_self();
151 if (pcpu->current_thread != RT_NULL)
152 {
153 rt_ubase_t lock_nest = rt_atomic_load(&(pcpu->current_thread->cpus_lock_nest));
154
155 rt_atomic_add(&(pcpu->current_thread->cpus_lock_nest), 1);
156 if (lock_nest == 0)
157 {
158 rt_enter_critical();
159 rt_hw_spin_lock(&_cpus_lock);
160 #ifdef RT_USING_DEBUG
161 _cpus_critical_level = rt_critical_level();
162 #endif /* RT_USING_DEBUG */
163
164 #ifdef RT_DEBUGING_SPINLOCK
165 _cpus_lock_owner = pcpu->current_thread;
166 _cpus_lock_pc = __GET_RETURN_ADDRESS;
167 #endif /* RT_DEBUGING_SPINLOCK */
168 }
169 }
170
171 return level;
172 }
173 RTM_EXPORT(rt_cpus_lock);
174
175 /**
176 * @brief This function will restore all cpus's scheduler and restore local irq.
177 *
178 * @param level is interrupt status returned by rt_cpus_lock().
179 */
rt_cpus_unlock(rt_base_t level)180 void rt_cpus_unlock(rt_base_t level)
181 {
182 struct rt_cpu* pcpu = rt_cpu_self();
183
184 if (pcpu->current_thread != RT_NULL)
185 {
186 rt_base_t critical_level = 0;
187 RT_ASSERT(rt_atomic_load(&(pcpu->current_thread->cpus_lock_nest)) > 0);
188 rt_atomic_sub(&(pcpu->current_thread->cpus_lock_nest), 1);
189
190 if (pcpu->current_thread->cpus_lock_nest == 0)
191 {
192 #if defined(RT_DEBUGING_SPINLOCK)
193 _cpus_lock_owner = __OWNER_MAGIC;
194 _cpus_lock_pc = RT_NULL;
195 #endif /* RT_DEBUGING_SPINLOCK */
196 #ifdef RT_USING_DEBUG
197 critical_level = _cpus_critical_level;
198 _cpus_critical_level = 0;
199 #endif /* RT_USING_DEBUG */
200 rt_hw_spin_unlock(&_cpus_lock);
201 rt_exit_critical_safe(critical_level);
202 }
203 }
204 rt_hw_local_irq_enable(level);
205 }
206 RTM_EXPORT(rt_cpus_unlock);
207
208 /**
209 * This function is invoked by scheduler.
210 * It will restore the lock state to whatever the thread's counter expects.
211 * If target thread not locked the cpus then unlock the cpus lock.
212 *
213 * @param thread is a pointer to the target thread.
214 */
rt_cpus_lock_status_restore(struct rt_thread * thread)215 void rt_cpus_lock_status_restore(struct rt_thread *thread)
216 {
217 #if defined(ARCH_MM_MMU) && defined(RT_USING_SMART)
218 lwp_aspace_switch(thread);
219 #endif
220 rt_sched_post_ctx_switch(thread);
221 }
222 RTM_EXPORT(rt_cpus_lock_status_restore);
223
224 /* A safe API with debugging feature to be called in most codes */
225
226 #undef rt_cpu_get_id
227 /**
228 * @brief Get logical CPU ID
229 *
230 * @return logical CPU ID
231 */
rt_cpu_get_id(void)232 rt_base_t rt_cpu_get_id(void)
233 {
234
235 RT_ASSERT(rt_sched_thread_is_binding(RT_NULL) ||
236 rt_hw_interrupt_is_disabled() ||
237 !rt_scheduler_is_available());
238
239 return rt_hw_cpu_id();
240 }
241