1 #![allow(dead_code)] 2 3 use system_error::SystemError; 4 5 use crate::{ 6 libs::{spinlock::SpinLock, wait_queue::WaitQueue}, 7 time::timer::schedule_timeout, 8 }; 9 10 const COMPLETE_ALL: u32 = u32::MAX; 11 const MAX_TIMEOUT: i64 = i64::MAX; 12 13 #[derive(Debug)] 14 pub struct Completion { 15 inner: SpinLock<InnerCompletion>, 16 } 17 18 impl Completion { new() -> Self19 pub const fn new() -> Self { 20 Self { 21 inner: SpinLock::new(InnerCompletion::new()), 22 } 23 } 24 25 /// @brief 基本函数：通用的处理wait命令的函数(即所有wait_for_completion函数最核心部分在这里) 26 /// 27 /// @param timeout jiffies 28 /// @param interuptible 设置进程是否能被打断 29 /// @return 返回剩余时间或者SystemError do_wait_for_common(&self, mut timeout: i64, interuptible: bool) -> Result<i64, SystemError>30 fn do_wait_for_common(&self, mut timeout: i64, interuptible: bool) -> Result<i64, SystemError> { 31 let mut inner = self.inner.lock_irqsave(); 32 33 if inner.done == 0 { 34 //loop break 类似 do while 保证进行一次信号检测 35 loop { 36 //检查当前线程是否有未处理的信号 37 // if (signal_pending_state(state, current)) { 38 // timeout = -ERESTARTSYS; 39 // break; 40 //} 41 42 if interuptible { 43 unsafe { inner.wait_queue.sleep_without_schedule() }; 44 } else { 45 unsafe { inner.wait_queue.sleep_without_schedule_uninterruptible() }; 46 } 47 drop(inner); 48 timeout = schedule_timeout(timeout)?; 49 inner = self.inner.lock_irqsave(); 50 if inner.done != 0 || timeout <= 0 { 51 break; 52 } 53 } 54 inner.wait_queue.wakeup(None); 55 if inner.done == 0 { 56 drop(inner); 57 return Ok(timeout); 58 } 59 } 60 if inner.done != COMPLETE_ALL { 61 inner.done -= 1; 62 } 63 drop(inner); 64 return Ok(if timeout > 0 { timeout } else { 1 }); 65 } 66 67 /// @brief 等待指定时间，超时后就返回, 同时设置pcb state为uninteruptible. 68 /// @param timeout 非负整数，等待指定时间，超时后就返回/或者提前done wait_for_completion_timeout(&self, timeout: i64) -> Result<i64, SystemError>69 pub fn wait_for_completion_timeout(&self, timeout: i64) -> Result<i64, SystemError> { 70 self.do_wait_for_common(timeout, false) 71 } 72 73 /// @brief 等待completion命令唤醒进程, 同时设置pcb state 为uninteruptible. wait_for_completion(&self) -> Result<i64, SystemError>74 pub fn wait_for_completion(&self) -> Result<i64, SystemError> { 75 self.do_wait_for_common(MAX_TIMEOUT, false) 76 } 77 78 /// @brief @brief 等待completion的完成，但是可以被中断 wait_for_completion_interruptible(&self) -> Result<i64, SystemError>79 pub fn wait_for_completion_interruptible(&self) -> Result<i64, SystemError> { 80 self.do_wait_for_common(MAX_TIMEOUT, true) 81 } 82 wait_for_completion_interruptible_timeout( &mut self, timeout: i64, ) -> Result<i64, SystemError>83 pub fn wait_for_completion_interruptible_timeout( 84 &mut self, 85 timeout: i64, 86 ) -> Result<i64, SystemError> { 87 assert!(timeout >= 0); 88 self.do_wait_for_common(timeout, true) 89 } 90 91 /// @brief 唤醒一个wait_queue中的节点 complete(&self)92 pub fn complete(&self) { 93 let mut inner = self.inner.lock_irqsave(); 94 if inner.done != COMPLETE_ALL { 95 inner.done = inner.done.saturating_add(1); 96 } 97 inner.wait_queue.wakeup(None); 98 // 脱离生命周期，自动释放guard 99 } 100 101 /// @brief 永久标记done为Complete_All，并从wait_queue中删除所有节点 complete_all(&self)102 pub fn complete_all(&self) { 103 let mut inner = self.inner.lock_irqsave(); 104 inner.done = COMPLETE_ALL; 105 inner.wait_queue.wakeup_all(None); 106 // 脱离生命周期，自动释放guard 107 } 108 109 /// @brief @brief 尝试获取completion的一个done！如果您在wait之前加上这个函数作为判断，说不定会加快运行速度。 110 /// 111 /// @return true - 表示不需要wait_for_completion，并且已经获取到了一个completion(即返回true意味着done已经被 减1 ) 112 /// @return false - 表示当前done=0，您需要进入等待，即wait_for_completion try_wait_for_completion(&mut self) -> bool113 pub fn try_wait_for_completion(&mut self) -> bool { 114 let mut inner = self.inner.lock_irqsave(); 115 if inner.done == 0 { 116 return false; 117 } 118 119 if inner.done != 0 { 120 return false; 121 } else if inner.done != COMPLETE_ALL { 122 inner.done -= 1; 123 } 124 return true; 125 // 脱离生命周期，自动释放guard 126 } 127 128 // @brief 测试一个completion是否有waiter。（即done是不是等于0） completion_done(&self) -> bool129 pub fn completion_done(&self) -> bool { 130 let inner = self.inner.lock_irqsave(); 131 if inner.done == 0 { 132 return false; 133 } 134 135 if inner.done == 0 { 136 return false; 137 } 138 return true; 139 // 脱离生命周期，自动释放guard 140 } 141 } 142 #[derive(Debug)] 143 pub struct InnerCompletion { 144 done: u32, 145 wait_queue: WaitQueue, 146 } 147 148 impl InnerCompletion { new() -> Self149 pub const fn new() -> Self { 150 Self { 151 done: 0, 152 wait_queue: WaitQueue::default(), 153 } 154 } 155 } 156