1 use core::{ 2 fmt, 3 hash::Hash, 4 hint::spin_loop, 5 intrinsics::{likely, unlikely}, 6 mem::ManuallyDrop, 7 sync::atomic::{compiler_fence, fence, AtomicBool, AtomicUsize, Ordering}, 8 }; 9 10 use alloc::{ 11 ffi::CString, 12 string::{String, ToString}, 13 sync::{Arc, Weak}, 14 vec::Vec, 15 }; 16 use cred::INIT_CRED; 17 use hashbrown::HashMap; 18 use log::{debug, error, info, warn}; 19 use system_error::SystemError; 20 21 use crate::{ 22 arch::{ 23 cpu::current_cpu_id, 24 ipc::signal::{AtomicSignal, SigSet, Signal}, 25 process::ArchPCBInfo, 26 CurrentIrqArch, 27 }, 28 driver::tty::tty_core::TtyCore, 29 exception::InterruptArch, 30 filesystem::{ 31 procfs::procfs_unregister_pid, 32 vfs::{file::FileDescriptorVec, FileType}, 33 }, 34 ipc::signal_types::{SigInfo, SigPending, SignalStruct}, 35 libs::{ 36 align::AlignedBox, 37 casting::DowncastArc, 38 futex::{ 39 constant::{FutexFlag, FUTEX_BITSET_MATCH_ANY}, 40 futex::{Futex, RobustListHead}, 41 }, 42 lock_free_flags::LockFreeFlags, 43 rwlock::{RwLock, RwLockReadGuard, RwLockWriteGuard}, 44 spinlock::{SpinLock, SpinLockGuard}, 45 wait_queue::WaitQueue, 46 }, 47 mm::{ 48 percpu::{PerCpu, PerCpuVar}, 49 set_IDLE_PROCESS_ADDRESS_SPACE, 50 ucontext::AddressSpace, 51 VirtAddr, 52 }, 53 net::socket::SocketInode, 54 sched::completion::Completion, 55 sched::{ 56 cpu_rq, fair::FairSchedEntity, prio::MAX_PRIO, DequeueFlag, EnqueueFlag, OnRq, SchedMode, 57 WakeupFlags, __schedule, 58 }, 59 smp::{ 60 core::smp_get_processor_id, 61 cpu::{AtomicProcessorId, ProcessorId}, 62 kick_cpu, 63 }, 64 syscall::{user_access::clear_user, Syscall}, 65 }; 66 use timer::AlarmTimer; 67 68 use self::{cred::Cred, kthread::WorkerPrivate}; 69 70 pub mod abi; 71 pub mod c_adapter; 72 pub mod cred; 73 pub mod exec; 74 pub mod exit; 75 pub mod fork; 76 pub mod idle; 77 pub mod kthread; 78 pub mod pid; 79 pub mod resource; 80 pub mod stdio; 81 pub mod syscall; 82 pub mod timer; 83 pub mod utils; 84 85 /// 系统中所有进程的pcb 86 static ALL_PROCESS: SpinLock<Option<HashMap<Pid, Arc<ProcessControlBlock>>>> = SpinLock::new(None); 87 88 pub static mut PROCESS_SWITCH_RESULT: Option<PerCpuVar<SwitchResult>> = None; 89 90 /// 一个只改变1次的全局变量，标志进程管理器是否已经初始化完成 91 static mut __PROCESS_MANAGEMENT_INIT_DONE: bool = false; 92 93 #[derive(Debug)] 94 pub struct SwitchResult { 95 pub prev_pcb: Option<Arc<ProcessControlBlock>>, 96 pub next_pcb: Option<Arc<ProcessControlBlock>>, 97 } 98 99 impl SwitchResult { 100 pub fn new() -> Self { 101 Self { 102 prev_pcb: None, 103 next_pcb: None, 104 } 105 } 106 } 107 108 #[derive(Debug)] 109 pub struct ProcessManager; 110 impl ProcessManager { 111 #[inline(never)] 112 fn init() { 113 static INIT_FLAG: AtomicBool = AtomicBool::new(false); 114 if INIT_FLAG 115 .compare_exchange(false, true, Ordering::SeqCst, Ordering::SeqCst) 116 .is_err() 117 { 118 panic!("ProcessManager has been initialized!"); 119 } 120 121 unsafe { 122 compiler_fence(Ordering::SeqCst); 123 debug!("To create address space for INIT process."); 124 // test_buddy(); 125 set_IDLE_PROCESS_ADDRESS_SPACE( 126 AddressSpace::new(true).expect("Failed to create address space for INIT process."), 127 ); 128 debug!("INIT process address space created."); 129 compiler_fence(Ordering::SeqCst); 130 }; 131 132 ALL_PROCESS.lock_irqsave().replace(HashMap::new()); 133 Self::init_switch_result(); 134 Self::arch_init(); 135 debug!("process arch init done."); 136 Self::init_idle(); 137 debug!("process idle init done."); 138 139 unsafe { __PROCESS_MANAGEMENT_INIT_DONE = true }; 140 info!("Process Manager initialized."); 141 } 142 143 fn init_switch_result() { 144 let mut switch_res_vec: Vec<SwitchResult> = Vec::new(); 145 for _ in 0..PerCpu::MAX_CPU_NUM { 146 switch_res_vec.push(SwitchResult::new()); 147 } 148 unsafe { 149 PROCESS_SWITCH_RESULT = Some(PerCpuVar::new(switch_res_vec).unwrap()); 150 } 151 } 152 153 /// 判断进程管理器是否已经初始化完成 154 #[allow(dead_code)] 155 pub fn initialized() -> bool { 156 unsafe { __PROCESS_MANAGEMENT_INIT_DONE } 157 } 158 159 /// 获取当前进程的pcb 160 pub fn current_pcb() -> Arc<ProcessControlBlock> { 161 if unlikely(unsafe { !__PROCESS_MANAGEMENT_INIT_DONE }) { 162 error!("unsafe__PROCESS_MANAGEMENT_INIT_DONE == false"); 163 loop { 164 spin_loop(); 165 } 166 } 167 return ProcessControlBlock::arch_current_pcb(); 168 } 169 170 /// 获取当前进程的pid 171 /// 172 /// 如果进程管理器未初始化完成，那么返回0 173 pub fn current_pid() -> Pid { 174 if unlikely(unsafe { !__PROCESS_MANAGEMENT_INIT_DONE }) { 175 return Pid(0); 176 } 177 178 return ProcessManager::current_pcb().pid(); 179 } 180 181 /// 增加当前进程的锁持有计数 182 #[inline(always)] 183 pub fn preempt_disable() { 184 if likely(unsafe { __PROCESS_MANAGEMENT_INIT_DONE }) { 185 ProcessManager::current_pcb().preempt_disable(); 186 } 187 } 188 189 /// 减少当前进程的锁持有计数 190 #[inline(always)] 191 pub fn preempt_enable() { 192 if likely(unsafe { __PROCESS_MANAGEMENT_INIT_DONE }) { 193 ProcessManager::current_pcb().preempt_enable(); 194 } 195 } 196 197 /// 根据pid获取进程的pcb 198 /// 199 /// ## 参数 200 /// 201 /// - `pid` : 进程的pid 202 /// 203 /// ## 返回值 204 /// 205 /// 如果找到了对应的进程，那么返回该进程的pcb，否则返回None 206 pub fn find(pid: Pid) -> Option<Arc<ProcessControlBlock>> { 207 return ALL_PROCESS.lock_irqsave().as_ref()?.get(&pid).cloned(); 208 } 209 210 /// 向系统中添加一个进程的pcb 211 /// 212 /// ## 参数 213 /// 214 /// - `pcb` : 进程的pcb 215 /// 216 /// ## 返回值 217 /// 218 /// 无 219 pub fn add_pcb(pcb: Arc<ProcessControlBlock>) { 220 ALL_PROCESS 221 .lock_irqsave() 222 .as_mut() 223 .unwrap() 224 .insert(pcb.pid(), pcb.clone()); 225 } 226 227 /// 唤醒一个进程 228 pub fn wakeup(pcb: &Arc<ProcessControlBlock>) -> Result<(), SystemError> { 229 let _guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 230 let state = pcb.sched_info().inner_lock_read_irqsave().state(); 231 if state.is_blocked() { 232 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 233 let state = writer.state(); 234 if state.is_blocked() { 235 writer.set_state(ProcessState::Runnable); 236 writer.set_wakeup(); 237 238 // avoid deadlock 239 drop(writer); 240 241 let rq = 242 cpu_rq(pcb.sched_info().on_cpu().unwrap_or(current_cpu_id()).data() as usize); 243 244 let (rq, _guard) = rq.self_lock(); 245 rq.update_rq_clock(); 246 rq.activate_task( 247 pcb, 248 EnqueueFlag::ENQUEUE_WAKEUP | EnqueueFlag::ENQUEUE_NOCLOCK, 249 ); 250 251 rq.check_preempt_currnet(pcb, WakeupFlags::empty()); 252 253 // sched_enqueue(pcb.clone(), true); 254 return Ok(()); 255 } else if state.is_exited() { 256 return Err(SystemError::EINVAL); 257 } else { 258 return Ok(()); 259 } 260 } else if state.is_exited() { 261 return Err(SystemError::EINVAL); 262 } else { 263 return Ok(()); 264 } 265 } 266 267 /// 唤醒暂停的进程 268 pub fn wakeup_stop(pcb: &Arc<ProcessControlBlock>) -> Result<(), SystemError> { 269 let _guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 270 let state = pcb.sched_info().inner_lock_read_irqsave().state(); 271 if let ProcessState::Stopped = state { 272 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 273 let state = writer.state(); 274 if let ProcessState::Stopped = state { 275 writer.set_state(ProcessState::Runnable); 276 // avoid deadlock 277 drop(writer); 278 279 let rq = cpu_rq(pcb.sched_info().on_cpu().unwrap().data() as usize); 280 281 let (rq, _guard) = rq.self_lock(); 282 rq.update_rq_clock(); 283 rq.activate_task( 284 pcb, 285 EnqueueFlag::ENQUEUE_WAKEUP | EnqueueFlag::ENQUEUE_NOCLOCK, 286 ); 287 288 rq.check_preempt_currnet(pcb, WakeupFlags::empty()); 289 290 // sched_enqueue(pcb.clone(), true); 291 return Ok(()); 292 } else if state.is_runnable() { 293 return Ok(()); 294 } else { 295 return Err(SystemError::EINVAL); 296 } 297 } else if state.is_runnable() { 298 return Ok(()); 299 } else { 300 return Err(SystemError::EINVAL); 301 } 302 } 303 304 /// 标志当前进程永久睡眠，但是发起调度的工作，应该由调用者完成 305 /// 306 /// ## 注意 307 /// 308 /// - 进入当前函数之前，不能持有sched_info的锁 309 /// - 进入当前函数之前，必须关闭中断 310 /// - 进入当前函数之后必须保证逻辑的正确性，避免被重复加入调度队列 311 pub fn mark_sleep(interruptable: bool) -> Result<(), SystemError> { 312 assert!( 313 !CurrentIrqArch::is_irq_enabled(), 314 "interrupt must be disabled before enter ProcessManager::mark_sleep()" 315 ); 316 let pcb = ProcessManager::current_pcb(); 317 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 318 if !matches!(writer.state(), ProcessState::Exited(_)) { 319 writer.set_state(ProcessState::Blocked(interruptable)); 320 writer.set_sleep(); 321 pcb.flags().insert(ProcessFlags::NEED_SCHEDULE); 322 fence(Ordering::SeqCst); 323 drop(writer); 324 return Ok(()); 325 } 326 return Err(SystemError::EINTR); 327 } 328 329 /// 标志当前进程为停止状态，但是发起调度的工作，应该由调用者完成 330 /// 331 /// ## 注意 332 /// 333 /// - 进入当前函数之前，不能持有sched_info的锁 334 /// - 进入当前函数之前，必须关闭中断 335 pub fn mark_stop() -> Result<(), SystemError> { 336 assert!( 337 !CurrentIrqArch::is_irq_enabled(), 338 "interrupt must be disabled before enter ProcessManager::mark_stop()" 339 ); 340 341 let pcb = ProcessManager::current_pcb(); 342 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 343 if !matches!(writer.state(), ProcessState::Exited(_)) { 344 writer.set_state(ProcessState::Stopped); 345 pcb.flags().insert(ProcessFlags::NEED_SCHEDULE); 346 drop(writer); 347 348 return Ok(()); 349 } 350 return Err(SystemError::EINTR); 351 } 352 /// 当子进程退出后向父进程发送通知 353 fn exit_notify() { 354 let current = ProcessManager::current_pcb(); 355 // 让INIT进程收养所有子进程 356 if current.pid() != Pid(1) { 357 unsafe { 358 current 359 .adopt_childen() 360 .unwrap_or_else(|e| panic!("adopte_childen failed: error: {e:?}")) 361 }; 362 let r = current.parent_pcb.read_irqsave().upgrade(); 363 if r.is_none() { 364 return; 365 } 366 let parent_pcb = r.unwrap(); 367 let r = Syscall::kill(parent_pcb.pid(), Signal::SIGCHLD as i32); 368 if r.is_err() { 369 warn!( 370 "failed to send kill signal to {:?}'s parent pcb {:?}", 371 current.pid(), 372 parent_pcb.pid() 373 ); 374 } 375 // todo: 这里需要向父进程发送SIGCHLD信号 376 // todo: 这里还需要根据线程组的信息，决定信号的发送 377 } 378 } 379 380 /// 退出当前进程 381 /// 382 /// ## 参数 383 /// 384 /// - `exit_code` : 进程的退出码 385 pub fn exit(exit_code: usize) -> ! { 386 // 关中断 387 let _guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 388 let pcb = ProcessManager::current_pcb(); 389 let pid = pcb.pid(); 390 pcb.sched_info 391 .inner_lock_write_irqsave() 392 .set_state(ProcessState::Exited(exit_code)); 393 pcb.wait_queue.wakeup(Some(ProcessState::Blocked(true))); 394 395 let rq = cpu_rq(smp_get_processor_id().data() as usize); 396 let (rq, guard) = rq.self_lock(); 397 rq.deactivate_task( 398 pcb.clone(), 399 DequeueFlag::DEQUEUE_SLEEP | DequeueFlag::DEQUEUE_NOCLOCK, 400 ); 401 drop(guard); 402 403 // 进行进程退出后的工作 404 let thread = pcb.thread.write_irqsave(); 405 if let Some(addr) = thread.set_child_tid { 406 unsafe { clear_user(addr, core::mem::size_of::<i32>()).expect("clear tid failed") }; 407 } 408 409 if let Some(addr) = thread.clear_child_tid { 410 if Arc::strong_count(&pcb.basic().user_vm().expect("User VM Not found")) > 1 { 411 let _ = 412 Futex::futex_wake(addr, FutexFlag::FLAGS_MATCH_NONE, 1, FUTEX_BITSET_MATCH_ANY); 413 } 414 unsafe { clear_user(addr, core::mem::size_of::<i32>()).expect("clear tid failed") }; 415 } 416 417 RobustListHead::exit_robust_list(pcb.clone()); 418 419 // 如果是vfork出来的进程，则需要处理completion 420 if thread.vfork_done.is_some() { 421 thread.vfork_done.as_ref().unwrap().complete_all(); 422 } 423 drop(thread); 424 unsafe { pcb.basic_mut().set_user_vm(None) }; 425 426 // TODO 由于未实现进程组，tty记录的前台进程组等于当前进程，故退出前要置空 427 // 后续相关逻辑需要在SYS_EXIT_GROUP系统调用中实现 428 if let Some(tty) = pcb.sig_info_irqsave().tty() { 429 tty.core().contorl_info_irqsave().pgid = None; 430 } 431 pcb.sig_info_mut().set_tty(None); 432 433 drop(pcb); 434 ProcessManager::exit_notify(); 435 // unsafe { CurrentIrqArch::interrupt_enable() }; 436 __schedule(SchedMode::SM_NONE); 437 error!("pid {pid:?} exited but sched again!"); 438 #[allow(clippy::empty_loop)] 439 loop { 440 spin_loop(); 441 } 442 } 443 444 pub unsafe fn release(pid: Pid) { 445 let pcb = ProcessManager::find(pid); 446 if pcb.is_some() { 447 // let pcb = pcb.unwrap(); 448 // 判断该pcb是否在全局没有任何引用 449 // TODO: 当前，pcb的Arc指针存在泄露问题，引用计数不正确，打算在接下来实现debug专用的Arc，方便调试，然后解决这个bug。 450 // 因此目前暂时注释掉，使得能跑 451 // if Arc::strong_count(&pcb) <= 2 { 452 // drop(pcb); 453 // ALL_PROCESS.lock().as_mut().unwrap().remove(&pid); 454 // } else { 455 // // 如果不为1就panic 456 // let msg = format!("pcb '{:?}' is still referenced, strong count={}",pcb.pid(), Arc::strong_count(&pcb)); 457 // error!("{}", msg); 458 // panic!() 459 // } 460 461 ALL_PROCESS.lock_irqsave().as_mut().unwrap().remove(&pid); 462 } 463 } 464 465 /// 上下文切换完成后的钩子函数 466 unsafe fn switch_finish_hook() { 467 // debug!("switch_finish_hook"); 468 let prev_pcb = PROCESS_SWITCH_RESULT 469 .as_mut() 470 .unwrap() 471 .get_mut() 472 .prev_pcb 473 .take() 474 .expect("prev_pcb is None"); 475 let next_pcb = PROCESS_SWITCH_RESULT 476 .as_mut() 477 .unwrap() 478 .get_mut() 479 .next_pcb 480 .take() 481 .expect("next_pcb is None"); 482 483 // 由于进程切换前使用了SpinLockGuard::leak()，所以这里需要手动释放锁 484 fence(Ordering::SeqCst); 485 486 prev_pcb.arch_info.force_unlock(); 487 fence(Ordering::SeqCst); 488 489 next_pcb.arch_info.force_unlock(); 490 fence(Ordering::SeqCst); 491 } 492 493 /// 如果目标进程正在目标CPU上运行，那么就让这个cpu陷入内核态 494 /// 495 /// ## 参数 496 /// 497 /// - `pcb` : 进程的pcb 498 #[allow(dead_code)] 499 pub fn kick(pcb: &Arc<ProcessControlBlock>) { 500 ProcessManager::current_pcb().preempt_disable(); 501 let cpu_id = pcb.sched_info().on_cpu(); 502 503 if let Some(cpu_id) = cpu_id { 504 if pcb.pid() == cpu_rq(cpu_id.data() as usize).current().pid() { 505 kick_cpu(cpu_id).expect("ProcessManager::kick(): Failed to kick cpu"); 506 } 507 } 508 509 ProcessManager::current_pcb().preempt_enable(); 510 } 511 } 512 513 /// 上下文切换的钩子函数,当这个函数return的时候,将会发生上下文切换 514 #[cfg(target_arch = "x86_64")] 515 #[inline(never)] 516 pub unsafe extern "sysv64" fn switch_finish_hook() { 517 ProcessManager::switch_finish_hook(); 518 } 519 #[cfg(target_arch = "riscv64")] 520 #[inline(always)] 521 pub unsafe fn switch_finish_hook() { 522 ProcessManager::switch_finish_hook(); 523 } 524 525 int_like!(Pid, AtomicPid, usize, AtomicUsize); 526 527 impl fmt::Display for Pid { 528 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { 529 write!(f, "{}", self.0) 530 } 531 } 532 533 #[derive(Debug, Clone, Copy, PartialEq, Eq)] 534 pub enum ProcessState { 535 /// The process is running on a CPU or in a run queue. 536 Runnable, 537 /// The process is waiting for an event to occur. 538 /// 其中的bool表示该等待过程是否可以被打断。 539 /// - 如果该bool为true,那么，硬件中断/信号/其他系统事件都可以打断该等待过程，使得该进程重新进入Runnable状态。 540 /// - 如果该bool为false,那么，这个进程必须被显式的唤醒，才能重新进入Runnable状态。 541 Blocked(bool), 542 /// 进程被信号终止 543 Stopped, 544 /// 进程已经退出，usize表示进程的退出码 545 Exited(usize), 546 } 547 548 #[allow(dead_code)] 549 impl ProcessState { 550 #[inline(always)] 551 pub fn is_runnable(&self) -> bool { 552 return matches!(self, ProcessState::Runnable); 553 } 554 555 #[inline(always)] 556 pub fn is_blocked(&self) -> bool { 557 return matches!(self, ProcessState::Blocked(_)); 558 } 559 560 #[inline(always)] 561 pub fn is_blocked_interruptable(&self) -> bool { 562 return matches!(self, ProcessState::Blocked(true)); 563 } 564 565 /// Returns `true` if the process state is [`Exited`]. 566 #[inline(always)] 567 pub fn is_exited(&self) -> bool { 568 return matches!(self, ProcessState::Exited(_)); 569 } 570 571 /// Returns `true` if the process state is [`Stopped`]. 572 /// 573 /// [`Stopped`]: ProcessState::Stopped 574 #[inline(always)] 575 pub fn is_stopped(&self) -> bool { 576 matches!(self, ProcessState::Stopped) 577 } 578 579 /// Returns exit code if the process state is [`Exited`]. 580 #[inline(always)] 581 pub fn exit_code(&self) -> Option<usize> { 582 match self { 583 ProcessState::Exited(code) => Some(*code), 584 _ => None, 585 } 586 } 587 } 588 589 bitflags! { 590 /// pcb的标志位 591 pub struct ProcessFlags: usize { 592 /// 当前pcb表示一个内核线程 593 const KTHREAD = 1 << 0; 594 /// 当前进程需要被调度 595 const NEED_SCHEDULE = 1 << 1; 596 /// 进程由于vfork而与父进程存在资源共享 597 const VFORK = 1 << 2; 598 /// 进程不可被冻结 599 const NOFREEZE = 1 << 3; 600 /// 进程正在退出 601 const EXITING = 1 << 4; 602 /// 进程由于接收到终止信号唤醒 603 const WAKEKILL = 1 << 5; 604 /// 进程由于接收到信号而退出.(Killed by a signal) 605 const SIGNALED = 1 << 6; 606 /// 进程需要迁移到其他cpu上 607 const NEED_MIGRATE = 1 << 7; 608 /// 随机化的虚拟地址空间，主要用于动态链接器的加载 609 const RANDOMIZE = 1 << 8; 610 } 611 } 612 613 #[derive(Debug)] 614 pub struct ProcessControlBlock { 615 /// 当前进程的pid 616 pid: Pid, 617 /// 当前进程的线程组id（这个值在同一个线程组内永远不变） 618 tgid: Pid, 619 620 basic: RwLock<ProcessBasicInfo>, 621 /// 当前进程的自旋锁持有计数 622 preempt_count: AtomicUsize, 623 624 flags: LockFreeFlags<ProcessFlags>, 625 worker_private: SpinLock<Option<WorkerPrivate>>, 626 /// 进程的内核栈 627 kernel_stack: RwLock<KernelStack>, 628 629 /// 系统调用栈 630 syscall_stack: RwLock<KernelStack>, 631 632 /// 与调度相关的信息 633 sched_info: ProcessSchedulerInfo, 634 /// 与处理器架构相关的信息 635 arch_info: SpinLock<ArchPCBInfo>, 636 /// 与信号处理相关的信息(似乎可以是无锁的) 637 sig_info: RwLock<ProcessSignalInfo>, 638 /// 信号处理结构体 639 sig_struct: SpinLock<SignalStruct>, 640 /// 退出信号S 641 exit_signal: AtomicSignal, 642 643 /// 父进程指针 644 parent_pcb: RwLock<Weak<ProcessControlBlock>>, 645 /// 真实父进程指针 646 real_parent_pcb: RwLock<Weak<ProcessControlBlock>>, 647 648 /// 子进程链表 649 children: RwLock<Vec<Pid>>, 650 651 /// 等待队列 652 wait_queue: WaitQueue, 653 654 /// 线程信息 655 thread: RwLock<ThreadInfo>, 656 657 ///闹钟定时器 658 alarm_timer: SpinLock<Option<AlarmTimer>>, 659 660 /// 进程的robust lock列表 661 robust_list: RwLock<Option<RobustListHead>>, 662 663 /// 进程作为主体的凭证集 664 cred: SpinLock<Cred>, 665 } 666 667 impl ProcessControlBlock { 668 /// Generate a new pcb. 669 /// 670 /// ## 参数 671 /// 672 /// - `name` : 进程的名字 673 /// - `kstack` : 进程的内核栈 674 /// 675 /// ## 返回值 676 /// 677 /// 返回一个新的pcb 678 pub fn new(name: String, kstack: KernelStack) -> Arc<Self> { 679 return Self::do_create_pcb(name, kstack, false); 680 } 681 682 /// 创建一个新的idle进程 683 /// 684 /// 请注意，这个函数只能在进程管理初始化的时候调用。 685 pub fn new_idle(cpu_id: u32, kstack: KernelStack) -> Arc<Self> { 686 let name = format!("idle-{}", cpu_id); 687 return Self::do_create_pcb(name, kstack, true); 688 } 689 690 /// # 函数的功能 691 /// 692 /// 返回此函数是否是内核进程 693 /// 694 /// # 返回值 695 /// 696 /// 若进程是内核进程则返回true 否则返回false 697 pub fn is_kthread(&self) -> bool { 698 return matches!(self.flags(), &mut ProcessFlags::KTHREAD); 699 } 700 701 #[inline(never)] 702 fn do_create_pcb(name: String, kstack: KernelStack, is_idle: bool) -> Arc<Self> { 703 let (pid, ppid, cwd, cred) = if is_idle { 704 let cred = INIT_CRED.clone(); 705 (Pid(0), Pid(0), "/".to_string(), cred) 706 } else { 707 let ppid = ProcessManager::current_pcb().pid(); 708 let mut cred = ProcessManager::current_pcb().cred(); 709 cred.cap_permitted = cred.cap_ambient; 710 cred.cap_effective = cred.cap_ambient; 711 let cwd = ProcessManager::current_pcb().basic().cwd(); 712 (Self::generate_pid(), ppid, cwd, cred) 713 }; 714 715 let basic_info = ProcessBasicInfo::new(Pid(0), ppid, Pid(0), name, cwd, None); 716 let preempt_count = AtomicUsize::new(0); 717 let flags = unsafe { LockFreeFlags::new(ProcessFlags::empty()) }; 718 719 let sched_info = ProcessSchedulerInfo::new(None); 720 let arch_info = SpinLock::new(ArchPCBInfo::new(&kstack)); 721 722 let ppcb: Weak<ProcessControlBlock> = ProcessManager::find(ppid) 723 .map(|p| Arc::downgrade(&p)) 724 .unwrap_or_default(); 725 726 let pcb = Self { 727 pid, 728 tgid: pid, 729 basic: basic_info, 730 preempt_count, 731 flags, 732 kernel_stack: RwLock::new(kstack), 733 syscall_stack: RwLock::new(KernelStack::new().unwrap()), 734 worker_private: SpinLock::new(None), 735 sched_info, 736 arch_info, 737 sig_info: RwLock::new(ProcessSignalInfo::default()), 738 sig_struct: SpinLock::new(SignalStruct::new()), 739 exit_signal: AtomicSignal::new(Signal::SIGCHLD), 740 parent_pcb: RwLock::new(ppcb.clone()), 741 real_parent_pcb: RwLock::new(ppcb), 742 children: RwLock::new(Vec::new()), 743 wait_queue: WaitQueue::default(), 744 thread: RwLock::new(ThreadInfo::new()), 745 alarm_timer: SpinLock::new(None), 746 robust_list: RwLock::new(None), 747 cred: SpinLock::new(cred), 748 }; 749 750 // 初始化系统调用栈 751 #[cfg(target_arch = "x86_64")] 752 pcb.arch_info 753 .lock() 754 .init_syscall_stack(&pcb.syscall_stack.read()); 755 756 let pcb = Arc::new(pcb); 757 758 pcb.sched_info() 759 .sched_entity() 760 .force_mut() 761 .set_pcb(Arc::downgrade(&pcb)); 762 // 设置进程的arc指针到内核栈和系统调用栈的最低地址处 763 unsafe { 764 pcb.kernel_stack 765 .write() 766 .set_pcb(Arc::downgrade(&pcb)) 767 .unwrap(); 768 769 pcb.syscall_stack 770 .write() 771 .set_pcb(Arc::downgrade(&pcb)) 772 .unwrap() 773 }; 774 775 // 将当前pcb加入父进程的子进程哈希表中 776 if pcb.pid() > Pid(1) { 777 if let Some(ppcb_arc) = pcb.parent_pcb.read_irqsave().upgrade() { 778 let mut children = ppcb_arc.children.write_irqsave(); 779 children.push(pcb.pid()); 780 } else { 781 panic!("parent pcb is None"); 782 } 783 } 784 785 return pcb; 786 } 787 788 /// 生成一个新的pid 789 #[inline(always)] 790 fn generate_pid() -> Pid { 791 static NEXT_PID: AtomicPid = AtomicPid::new(Pid(1)); 792 return NEXT_PID.fetch_add(Pid(1), Ordering::SeqCst); 793 } 794 795 /// 返回当前进程的锁持有计数 796 #[inline(always)] 797 pub fn preempt_count(&self) -> usize { 798 return self.preempt_count.load(Ordering::SeqCst); 799 } 800 801 /// 增加当前进程的锁持有计数 802 #[inline(always)] 803 pub fn preempt_disable(&self) { 804 self.preempt_count.fetch_add(1, Ordering::SeqCst); 805 } 806 807 /// 减少当前进程的锁持有计数 808 #[inline(always)] 809 pub fn preempt_enable(&self) { 810 self.preempt_count.fetch_sub(1, Ordering::SeqCst); 811 } 812 813 #[inline(always)] 814 pub unsafe fn set_preempt_count(&self, count: usize) { 815 self.preempt_count.store(count, Ordering::SeqCst); 816 } 817 818 #[inline(always)] 819 pub fn flags(&self) -> &mut ProcessFlags { 820 return self.flags.get_mut(); 821 } 822 823 /// 请注意，这个值能在中断上下文中读取，但不能被中断上下文修改 824 /// 否则会导致死锁 825 #[inline(always)] 826 pub fn basic(&self) -> RwLockReadGuard<ProcessBasicInfo> { 827 return self.basic.read_irqsave(); 828 } 829 830 #[inline(always)] 831 pub fn set_name(&self, name: String) { 832 self.basic.write().set_name(name); 833 } 834 835 #[inline(always)] 836 pub fn basic_mut(&self) -> RwLockWriteGuard<ProcessBasicInfo> { 837 return self.basic.write_irqsave(); 838 } 839 840 /// # 获取arch info的锁，同时关闭中断 841 #[inline(always)] 842 pub fn arch_info_irqsave(&self) -> SpinLockGuard<ArchPCBInfo> { 843 return self.arch_info.lock_irqsave(); 844 } 845 846 /// # 获取arch info的锁，但是不关闭中断 847 /// 848 /// 由于arch info在进程切换的时候会使用到， 849 /// 因此在中断上下文外，获取arch info 而不irqsave是不安全的. 850 /// 851 /// 只能在以下情况下使用这个函数： 852 /// - 在中断上下文中（中断已经禁用），获取arch info的锁。 853 /// - 刚刚创建新的pcb 854 #[inline(always)] 855 pub unsafe fn arch_info(&self) -> SpinLockGuard<ArchPCBInfo> { 856 return self.arch_info.lock(); 857 } 858 859 #[inline(always)] 860 pub fn kernel_stack(&self) -> RwLockReadGuard<KernelStack> { 861 return self.kernel_stack.read(); 862 } 863 864 pub unsafe fn kernel_stack_force_ref(&self) -> &KernelStack { 865 self.kernel_stack.force_get_ref() 866 } 867 868 #[inline(always)] 869 #[allow(dead_code)] 870 pub fn kernel_stack_mut(&self) -> RwLockWriteGuard<KernelStack> { 871 return self.kernel_stack.write(); 872 } 873 874 #[inline(always)] 875 pub fn sched_info(&self) -> &ProcessSchedulerInfo { 876 return &self.sched_info; 877 } 878 879 #[inline(always)] 880 pub fn worker_private(&self) -> SpinLockGuard<Option<WorkerPrivate>> { 881 return self.worker_private.lock(); 882 } 883 884 #[inline(always)] 885 pub fn pid(&self) -> Pid { 886 return self.pid; 887 } 888 889 #[inline(always)] 890 pub fn tgid(&self) -> Pid { 891 return self.tgid; 892 } 893 894 /// 获取文件描述符表的Arc指针 895 #[inline(always)] 896 pub fn fd_table(&self) -> Arc<RwLock<FileDescriptorVec>> { 897 return self.basic.read().fd_table().unwrap(); 898 } 899 900 #[inline(always)] 901 pub fn cred(&self) -> Cred { 902 self.cred.lock().clone() 903 } 904 905 /// 根据文件描述符序号，获取socket对象的Arc指针 906 /// 907 /// ## 参数 908 /// 909 /// - `fd` 文件描述符序号 910 /// 911 /// ## 返回值 912 /// 913 /// Option(&mut Box<dyn Socket>) socket对象的可变引用. 如果文件描述符不是socket，那么返回None 914 pub fn get_socket(&self, fd: i32) -> Option<Arc<SocketInode>> { 915 let binding = ProcessManager::current_pcb().fd_table(); 916 let fd_table_guard = binding.read(); 917 918 let f = fd_table_guard.get_file_by_fd(fd)?; 919 drop(fd_table_guard); 920 921 if f.file_type() != FileType::Socket { 922 return None; 923 } 924 let socket: Arc<SocketInode> = f 925 .inode() 926 .downcast_arc::<SocketInode>() 927 .expect("Not a socket inode"); 928 return Some(socket); 929 } 930 931 /// 当前进程退出时,让初始进程收养所有子进程 932 unsafe fn adopt_childen(&self) -> Result<(), SystemError> { 933 match ProcessManager::find(Pid(1)) { 934 Some(init_pcb) => { 935 let childen_guard = self.children.write(); 936 let mut init_childen_guard = init_pcb.children.write(); 937 938 childen_guard.iter().for_each(|pid| { 939 init_childen_guard.push(*pid); 940 }); 941 942 return Ok(()); 943 } 944 _ => Err(SystemError::ECHILD), 945 } 946 } 947 948 /// 生成进程的名字 949 pub fn generate_name(program_path: &str, args: &Vec<CString>) -> String { 950 let mut name = program_path.to_string(); 951 for arg in args { 952 name.push(' '); 953 name.push_str(arg.to_string_lossy().as_ref()); 954 } 955 return name; 956 } 957 958 pub fn sig_info_irqsave(&self) -> RwLockReadGuard<ProcessSignalInfo> { 959 self.sig_info.read_irqsave() 960 } 961 962 pub fn try_siginfo_irqsave(&self, times: u8) -> Option<RwLockReadGuard<ProcessSignalInfo>> { 963 for _ in 0..times { 964 if let Some(r) = self.sig_info.try_read_irqsave() { 965 return Some(r); 966 } 967 } 968 969 return None; 970 } 971 972 pub fn sig_info_mut(&self) -> RwLockWriteGuard<ProcessSignalInfo> { 973 self.sig_info.write_irqsave() 974 } 975 976 pub fn try_siginfo_mut(&self, times: u8) -> Option<RwLockWriteGuard<ProcessSignalInfo>> { 977 for _ in 0..times { 978 if let Some(r) = self.sig_info.try_write_irqsave() { 979 return Some(r); 980 } 981 } 982 983 return None; 984 } 985 986 /// 判断当前进程是否有未处理的信号 987 pub fn has_pending_signal(&self) -> bool { 988 let sig_info = self.sig_info_irqsave(); 989 let has_pending = sig_info.sig_pending().has_pending(); 990 drop(sig_info); 991 return has_pending; 992 } 993 994 pub fn sig_struct(&self) -> SpinLockGuard<SignalStruct> { 995 self.sig_struct.lock_irqsave() 996 } 997 998 pub fn try_sig_struct_irqsave(&self, times: u8) -> Option<SpinLockGuard<SignalStruct>> { 999 for _ in 0..times { 1000 if let Ok(r) = self.sig_struct.try_lock_irqsave() { 1001 return Some(r); 1002 } 1003 } 1004 1005 return None; 1006 } 1007 1008 pub fn sig_struct_irqsave(&self) -> SpinLockGuard<SignalStruct> { 1009 self.sig_struct.lock_irqsave() 1010 } 1011 1012 #[inline(always)] 1013 pub fn get_robust_list(&self) -> RwLockReadGuard<Option<RobustListHead>> { 1014 return self.robust_list.read_irqsave(); 1015 } 1016 1017 #[inline(always)] 1018 pub fn set_robust_list(&self, new_robust_list: Option<RobustListHead>) { 1019 *self.robust_list.write_irqsave() = new_robust_list; 1020 } 1021 1022 pub fn alarm_timer_irqsave(&self) -> SpinLockGuard<Option<AlarmTimer>> { 1023 return self.alarm_timer.lock_irqsave(); 1024 } 1025 } 1026 1027 impl Drop for ProcessControlBlock { 1028 fn drop(&mut self) { 1029 let irq_guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 1030 // 在ProcFS中,解除进程的注册 1031 procfs_unregister_pid(self.pid()) 1032 .unwrap_or_else(|e| panic!("procfs_unregister_pid failed: error: {e:?}")); 1033 1034 if let Some(ppcb) = self.parent_pcb.read_irqsave().upgrade() { 1035 ppcb.children 1036 .write_irqsave() 1037 .retain(|pid| *pid != self.pid()); 1038 } 1039 1040 drop(irq_guard); 1041 } 1042 } 1043 1044 /// 线程信息 1045 #[derive(Debug)] 1046 pub struct ThreadInfo { 1047 // 来自用户空间记录用户线程id的地址，在该线程结束时将该地址置0以通知父进程 1048 clear_child_tid: Option<VirtAddr>, 1049 set_child_tid: Option<VirtAddr>, 1050 1051 vfork_done: Option<Arc<Completion>>, 1052 /// 线程组的组长 1053 group_leader: Weak<ProcessControlBlock>, 1054 } 1055 1056 impl ThreadInfo { 1057 pub fn new() -> Self { 1058 Self { 1059 clear_child_tid: None, 1060 set_child_tid: None, 1061 vfork_done: None, 1062 group_leader: Weak::default(), 1063 } 1064 } 1065 1066 pub fn group_leader(&self) -> Option<Arc<ProcessControlBlock>> { 1067 return self.group_leader.upgrade(); 1068 } 1069 } 1070 1071 /// 进程的基本信息 1072 /// 1073 /// 这个结构体保存进程的基本信息，主要是那些不会随着进程的运行而经常改变的信息。 1074 #[derive(Debug)] 1075 pub struct ProcessBasicInfo { 1076 /// 当前进程的进程组id 1077 pgid: Pid, 1078 /// 当前进程的父进程的pid 1079 ppid: Pid, 1080 /// 当前进程所属会话id 1081 sid: Pid, 1082 /// 进程的名字 1083 name: String, 1084 1085 /// 当前进程的工作目录 1086 cwd: String, 1087 1088 /// 用户地址空间 1089 user_vm: Option<Arc<AddressSpace>>, 1090 1091 /// 文件描述符表 1092 fd_table: Option<Arc<RwLock<FileDescriptorVec>>>, 1093 } 1094 1095 impl ProcessBasicInfo { 1096 #[inline(never)] 1097 pub fn new( 1098 pgid: Pid, 1099 ppid: Pid, 1100 sid: Pid, 1101 name: String, 1102 cwd: String, 1103 user_vm: Option<Arc<AddressSpace>>, 1104 ) -> RwLock<Self> { 1105 let fd_table = Arc::new(RwLock::new(FileDescriptorVec::new())); 1106 return RwLock::new(Self { 1107 pgid, 1108 ppid, 1109 sid, 1110 name, 1111 cwd, 1112 user_vm, 1113 fd_table: Some(fd_table), 1114 }); 1115 } 1116 1117 pub fn pgid(&self) -> Pid { 1118 return self.pgid; 1119 } 1120 1121 pub fn ppid(&self) -> Pid { 1122 return self.ppid; 1123 } 1124 1125 pub fn sid(&self) -> Pid { 1126 return self.sid; 1127 } 1128 1129 pub fn name(&self) -> &str { 1130 return &self.name; 1131 } 1132 1133 pub fn set_name(&mut self, name: String) { 1134 self.name = name; 1135 } 1136 1137 pub fn cwd(&self) -> String { 1138 return self.cwd.clone(); 1139 } 1140 pub fn set_cwd(&mut self, path: String) { 1141 return self.cwd = path; 1142 } 1143 1144 pub fn user_vm(&self) -> Option<Arc<AddressSpace>> { 1145 return self.user_vm.clone(); 1146 } 1147 1148 pub unsafe fn set_user_vm(&mut self, user_vm: Option<Arc<AddressSpace>>) { 1149 self.user_vm = user_vm; 1150 } 1151 1152 pub fn fd_table(&self) -> Option<Arc<RwLock<FileDescriptorVec>>> { 1153 return self.fd_table.clone(); 1154 } 1155 1156 pub fn set_fd_table(&mut self, fd_table: Option<Arc<RwLock<FileDescriptorVec>>>) { 1157 self.fd_table = fd_table; 1158 } 1159 } 1160 1161 #[derive(Debug)] 1162 pub struct ProcessSchedulerInfo { 1163 /// 当前进程所在的cpu 1164 on_cpu: AtomicProcessorId, 1165 /// 如果当前进程等待被迁移到另一个cpu核心上（也就是flags中的PF_NEED_MIGRATE被置位）， 1166 /// 该字段存储要被迁移到的目标处理器核心号 1167 // migrate_to: AtomicProcessorId, 1168 inner_locked: RwLock<InnerSchedInfo>, 1169 /// 进程的调度优先级 1170 // priority: SchedPriority, 1171 /// 当前进程的虚拟运行时间 1172 // virtual_runtime: AtomicIsize, 1173 /// 由实时调度器管理的时间片 1174 // rt_time_slice: AtomicIsize, 1175 pub sched_stat: RwLock<SchedInfo>, 1176 /// 调度策略 1177 pub sched_policy: RwLock<crate::sched::SchedPolicy>, 1178 /// cfs调度实体 1179 pub sched_entity: Arc<FairSchedEntity>, 1180 pub on_rq: SpinLock<OnRq>, 1181 1182 pub prio_data: RwLock<PrioData>, 1183 } 1184 1185 #[derive(Debug, Default)] 1186 #[allow(dead_code)] 1187 pub struct SchedInfo { 1188 /// 记录任务在特定 CPU 上运行的次数 1189 pub pcount: usize, 1190 /// 记录任务等待在运行队列上的时间 1191 pub run_delay: usize, 1192 /// 记录任务上次在 CPU 上运行的时间戳 1193 pub last_arrival: u64, 1194 /// 记录任务上次被加入到运行队列中的时间戳 1195 pub last_queued: u64, 1196 } 1197 1198 #[derive(Debug)] 1199 #[allow(dead_code)] 1200 pub struct PrioData { 1201 pub prio: i32, 1202 pub static_prio: i32, 1203 pub normal_prio: i32, 1204 } 1205 1206 impl Default for PrioData { 1207 fn default() -> Self { 1208 Self { 1209 prio: MAX_PRIO - 20, 1210 static_prio: MAX_PRIO - 20, 1211 normal_prio: MAX_PRIO - 20, 1212 } 1213 } 1214 } 1215 1216 #[derive(Debug)] 1217 pub struct InnerSchedInfo { 1218 /// 当前进程的状态 1219 state: ProcessState, 1220 /// 进程的调度策略 1221 sleep: bool, 1222 } 1223 1224 impl InnerSchedInfo { 1225 pub fn state(&self) -> ProcessState { 1226 return self.state; 1227 } 1228 1229 pub fn set_state(&mut self, state: ProcessState) { 1230 self.state = state; 1231 } 1232 1233 pub fn set_sleep(&mut self) { 1234 self.sleep = true; 1235 } 1236 1237 pub fn set_wakeup(&mut self) { 1238 self.sleep = false; 1239 } 1240 1241 pub fn is_mark_sleep(&self) -> bool { 1242 self.sleep 1243 } 1244 } 1245 1246 impl ProcessSchedulerInfo { 1247 #[inline(never)] 1248 pub fn new(on_cpu: Option<ProcessorId>) -> Self { 1249 let cpu_id = on_cpu.unwrap_or(ProcessorId::INVALID); 1250 return Self { 1251 on_cpu: AtomicProcessorId::new(cpu_id), 1252 // migrate_to: AtomicProcessorId::new(ProcessorId::INVALID), 1253 inner_locked: RwLock::new(InnerSchedInfo { 1254 state: ProcessState::Blocked(false), 1255 sleep: false, 1256 }), 1257 // virtual_runtime: AtomicIsize::new(0), 1258 // rt_time_slice: AtomicIsize::new(0), 1259 // priority: SchedPriority::new(100).unwrap(), 1260 sched_stat: RwLock::new(SchedInfo::default()), 1261 sched_policy: RwLock::new(crate::sched::SchedPolicy::CFS), 1262 sched_entity: FairSchedEntity::new(), 1263 on_rq: SpinLock::new(OnRq::None), 1264 prio_data: RwLock::new(PrioData::default()), 1265 }; 1266 } 1267 1268 pub fn sched_entity(&self) -> Arc<FairSchedEntity> { 1269 return self.sched_entity.clone(); 1270 } 1271 1272 pub fn on_cpu(&self) -> Option<ProcessorId> { 1273 let on_cpu = self.on_cpu.load(Ordering::SeqCst); 1274 if on_cpu == ProcessorId::INVALID { 1275 return None; 1276 } else { 1277 return Some(on_cpu); 1278 } 1279 } 1280 1281 pub fn set_on_cpu(&self, on_cpu: Option<ProcessorId>) { 1282 if let Some(cpu_id) = on_cpu { 1283 self.on_cpu.store(cpu_id, Ordering::SeqCst); 1284 } else { 1285 self.on_cpu.store(ProcessorId::INVALID, Ordering::SeqCst); 1286 } 1287 } 1288 1289 // pub fn migrate_to(&self) -> Option<ProcessorId> { 1290 // let migrate_to = self.migrate_to.load(Ordering::SeqCst); 1291 // if migrate_to == ProcessorId::INVALID { 1292 // return None; 1293 // } else { 1294 // return Some(migrate_to); 1295 // } 1296 // } 1297 1298 // pub fn set_migrate_to(&self, migrate_to: Option<ProcessorId>) { 1299 // if let Some(data) = migrate_to { 1300 // self.migrate_to.store(data, Ordering::SeqCst); 1301 // } else { 1302 // self.migrate_to 1303 // .store(ProcessorId::INVALID, Ordering::SeqCst) 1304 // } 1305 // } 1306 1307 pub fn inner_lock_write_irqsave(&self) -> RwLockWriteGuard<InnerSchedInfo> { 1308 return self.inner_locked.write_irqsave(); 1309 } 1310 1311 pub fn inner_lock_read_irqsave(&self) -> RwLockReadGuard<InnerSchedInfo> { 1312 return self.inner_locked.read_irqsave(); 1313 } 1314 1315 // pub fn inner_lock_try_read_irqsave( 1316 // &self, 1317 // times: u8, 1318 // ) -> Option<RwLockReadGuard<InnerSchedInfo>> { 1319 // for _ in 0..times { 1320 // if let Some(r) = self.inner_locked.try_read_irqsave() { 1321 // return Some(r); 1322 // } 1323 // } 1324 1325 // return None; 1326 // } 1327 1328 // pub fn inner_lock_try_upgradable_read_irqsave( 1329 // &self, 1330 // times: u8, 1331 // ) -> Option<RwLockUpgradableGuard<InnerSchedInfo>> { 1332 // for _ in 0..times { 1333 // if let Some(r) = self.inner_locked.try_upgradeable_read_irqsave() { 1334 // return Some(r); 1335 // } 1336 // } 1337 1338 // return None; 1339 // } 1340 1341 // pub fn virtual_runtime(&self) -> isize { 1342 // return self.virtual_runtime.load(Ordering::SeqCst); 1343 // } 1344 1345 // pub fn set_virtual_runtime(&self, virtual_runtime: isize) { 1346 // self.virtual_runtime 1347 // .store(virtual_runtime, Ordering::SeqCst); 1348 // } 1349 // pub fn increase_virtual_runtime(&self, delta: isize) { 1350 // self.virtual_runtime.fetch_add(delta, Ordering::SeqCst); 1351 // } 1352 1353 // pub fn rt_time_slice(&self) -> isize { 1354 // return self.rt_time_slice.load(Ordering::SeqCst); 1355 // } 1356 1357 // pub fn set_rt_time_slice(&self, rt_time_slice: isize) { 1358 // self.rt_time_slice.store(rt_time_slice, Ordering::SeqCst); 1359 // } 1360 1361 // pub fn increase_rt_time_slice(&self, delta: isize) { 1362 // self.rt_time_slice.fetch_add(delta, Ordering::SeqCst); 1363 // } 1364 1365 pub fn policy(&self) -> crate::sched::SchedPolicy { 1366 return *self.sched_policy.read_irqsave(); 1367 } 1368 } 1369 1370 #[derive(Debug, Clone)] 1371 pub struct KernelStack { 1372 stack: Option<AlignedBox<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>>, 1373 /// 标记该内核栈是否可以被释放 1374 can_be_freed: bool, 1375 } 1376 1377 impl KernelStack { 1378 pub const SIZE: usize = 0x4000; 1379 pub const ALIGN: usize = 0x4000; 1380 1381 pub fn new() -> Result<Self, SystemError> { 1382 return Ok(Self { 1383 stack: Some( 1384 AlignedBox::<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>::new_zeroed()?, 1385 ), 1386 can_be_freed: true, 1387 }); 1388 } 1389 1390 /// 根据已有的空间，构造一个内核栈结构体 1391 /// 1392 /// 仅仅用于BSP启动时，为idle进程构造内核栈。其他时候使用这个函数，很可能造成错误！ 1393 pub unsafe fn from_existed(base: VirtAddr) -> Result<Self, SystemError> { 1394 if base.is_null() || !base.check_aligned(Self::ALIGN) { 1395 return Err(SystemError::EFAULT); 1396 } 1397 1398 return Ok(Self { 1399 stack: Some( 1400 AlignedBox::<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>::new_unchecked( 1401 base.data() as *mut [u8; KernelStack::SIZE], 1402 ), 1403 ), 1404 can_be_freed: false, 1405 }); 1406 } 1407 1408 /// 返回内核栈的起始虚拟地址(低地址) 1409 pub fn start_address(&self) -> VirtAddr { 1410 return VirtAddr::new(self.stack.as_ref().unwrap().as_ptr() as usize); 1411 } 1412 1413 /// 返回内核栈的结束虚拟地址(高地址)(不包含该地址) 1414 pub fn stack_max_address(&self) -> VirtAddr { 1415 return VirtAddr::new(self.stack.as_ref().unwrap().as_ptr() as usize + Self::SIZE); 1416 } 1417 1418 pub unsafe fn set_pcb(&mut self, pcb: Weak<ProcessControlBlock>) -> Result<(), SystemError> { 1419 // 将一个Weak<ProcessControlBlock>放到内核栈的最低地址处 1420 let p: *const ProcessControlBlock = Weak::into_raw(pcb); 1421 let stack_bottom_ptr = self.start_address().data() as *mut *const ProcessControlBlock; 1422 1423 // 如果内核栈的最低地址处已经有了一个pcb，那么，这里就不再设置,直接返回错误 1424 if unlikely(unsafe { !(*stack_bottom_ptr).is_null() }) { 1425 error!("kernel stack bottom is not null: {:p}", *stack_bottom_ptr); 1426 return Err(SystemError::EPERM); 1427 } 1428 // 将pcb的地址放到内核栈的最低地址处 1429 unsafe { 1430 *stack_bottom_ptr = p; 1431 } 1432 1433 return Ok(()); 1434 } 1435 1436 /// 清除内核栈的pcb指针 1437 /// 1438 /// ## 参数 1439 /// 1440 /// - `force` : 如果为true,那么，即使该内核栈的pcb指针不为null，也会被强制清除而不处理Weak指针问题 1441 pub unsafe fn clear_pcb(&mut self, force: bool) { 1442 let stack_bottom_ptr = self.start_address().data() as *mut *const ProcessControlBlock; 1443 if unlikely(unsafe { (*stack_bottom_ptr).is_null() }) { 1444 return; 1445 } 1446 1447 if !force { 1448 let pcb_ptr: Weak<ProcessControlBlock> = Weak::from_raw(*stack_bottom_ptr); 1449 drop(pcb_ptr); 1450 } 1451 1452 *stack_bottom_ptr = core::ptr::null(); 1453 } 1454 1455 /// 返回指向当前内核栈pcb的Arc指针 1456 #[allow(dead_code)] 1457 pub unsafe fn pcb(&self) -> Option<Arc<ProcessControlBlock>> { 1458 // 从内核栈的最低地址处取出pcb的地址 1459 let p = self.stack.as_ref().unwrap().as_ptr() as *const *const ProcessControlBlock; 1460 if unlikely(unsafe { (*p).is_null() }) { 1461 return None; 1462 } 1463 1464 // 为了防止内核栈的pcb指针被释放，这里需要将其包装一下，使得Arc的drop不会被调用 1465 let weak_wrapper: ManuallyDrop<Weak<ProcessControlBlock>> = 1466 ManuallyDrop::new(Weak::from_raw(*p)); 1467 1468 let new_arc: Arc<ProcessControlBlock> = weak_wrapper.upgrade()?; 1469 return Some(new_arc); 1470 } 1471 } 1472 1473 impl Drop for KernelStack { 1474 fn drop(&mut self) { 1475 if self.stack.is_some() { 1476 let ptr = self.stack.as_ref().unwrap().as_ptr() as *const *const ProcessControlBlock; 1477 if unsafe { !(*ptr).is_null() } { 1478 let pcb_ptr: Weak<ProcessControlBlock> = unsafe { Weak::from_raw(*ptr) }; 1479 drop(pcb_ptr); 1480 } 1481 } 1482 // 如果该内核栈不可以被释放，那么，这里就forget，不调用AlignedBox的drop函数 1483 if !self.can_be_freed { 1484 let bx = self.stack.take(); 1485 core::mem::forget(bx); 1486 } 1487 } 1488 } 1489 1490 pub fn process_init() { 1491 ProcessManager::init(); 1492 } 1493 1494 #[derive(Debug)] 1495 pub struct ProcessSignalInfo { 1496 // 当前进程 1497 sig_block: SigSet, 1498 // sig_pending 中存储当前线程要处理的信号 1499 sig_pending: SigPending, 1500 // sig_shared_pending 中存储当前线程所属进程要处理的信号 1501 sig_shared_pending: SigPending, 1502 // 当前进程对应的tty 1503 tty: Option<Arc<TtyCore>>, 1504 } 1505 1506 impl ProcessSignalInfo { 1507 pub fn sig_block(&self) -> &SigSet { 1508 &self.sig_block 1509 } 1510 1511 pub fn sig_pending(&self) -> &SigPending { 1512 &self.sig_pending 1513 } 1514 1515 pub fn sig_pending_mut(&mut self) -> &mut SigPending { 1516 &mut self.sig_pending 1517 } 1518 1519 pub fn sig_block_mut(&mut self) -> &mut SigSet { 1520 &mut self.sig_block 1521 } 1522 1523 pub fn sig_shared_pending_mut(&mut self) -> &mut SigPending { 1524 &mut self.sig_shared_pending 1525 } 1526 1527 pub fn sig_shared_pending(&self) -> &SigPending { 1528 &self.sig_shared_pending 1529 } 1530 1531 pub fn tty(&self) -> Option<Arc<TtyCore>> { 1532 self.tty.clone() 1533 } 1534 1535 pub fn set_tty(&mut self, tty: Option<Arc<TtyCore>>) { 1536 self.tty = tty; 1537 } 1538 1539 /// 从 pcb 的 siginfo中取出下一个要处理的信号，先处理线程信号，再处理进程信号 1540 /// 1541 /// ## 参数 1542 /// 1543 /// - `sig_mask` 被忽略掉的信号 1544 /// 1545 pub fn dequeue_signal(&mut self, sig_mask: &SigSet) -> (Signal, Option<SigInfo>) { 1546 let res = self.sig_pending.dequeue_signal(sig_mask); 1547 if res.0 != Signal::INVALID { 1548 return res; 1549 } else { 1550 return self.sig_shared_pending.dequeue_signal(sig_mask); 1551 } 1552 } 1553 } 1554 1555 impl Default for ProcessSignalInfo { 1556 fn default() -> Self { 1557 Self { 1558 sig_block: SigSet::empty(), 1559 sig_pending: SigPending::default(), 1560 sig_shared_pending: SigPending::default(), 1561 tty: None, 1562 } 1563 } 1564 } 1565