1 use core::{ 2 hash::{Hash, Hasher}, 3 hint::spin_loop, 4 intrinsics::{likely, unlikely}, 5 mem::ManuallyDrop, 6 sync::atomic::{compiler_fence, AtomicBool, AtomicI32, AtomicIsize, AtomicUsize, Ordering}, 7 }; 8 9 use alloc::{ 10 string::{String, ToString}, 11 sync::{Arc, Weak}, 12 vec::Vec, 13 }; 14 use hashbrown::HashMap; 15 use system_error::SystemError; 16 17 use crate::{ 18 arch::{ 19 ipc::signal::{AtomicSignal, SigSet, Signal}, 20 process::ArchPCBInfo, 21 sched::sched, 22 CurrentIrqArch, 23 }, 24 exception::InterruptArch, 25 filesystem::{ 26 procfs::procfs_unregister_pid, 27 vfs::{file::FileDescriptorVec, FileType}, 28 }, 29 ipc::signal_types::{SigInfo, SigPending, SignalStruct}, 30 kdebug, kinfo, 31 libs::{ 32 align::AlignedBox, 33 casting::DowncastArc, 34 futex::{ 35 constant::{FutexFlag, FUTEX_BITSET_MATCH_ANY}, 36 futex::Futex, 37 }, 38 lock_free_flags::LockFreeFlags, 39 rwlock::{RwLock, RwLockReadGuard, RwLockUpgradableGuard, RwLockWriteGuard}, 40 spinlock::{SpinLock, SpinLockGuard}, 41 wait_queue::WaitQueue, 42 }, 43 mm::{percpu::PerCpuVar, set_INITIAL_PROCESS_ADDRESS_SPACE, ucontext::AddressSpace, VirtAddr}, 44 net::socket::SocketInode, 45 sched::{ 46 completion::Completion, 47 core::{sched_enqueue, CPU_EXECUTING}, 48 SchedPolicy, SchedPriority, 49 }, 50 smp::kick_cpu, 51 syscall::{user_access::clear_user, Syscall}, 52 }; 53 54 use self::kthread::WorkerPrivate; 55 56 pub mod abi; 57 pub mod c_adapter; 58 pub mod exec; 59 pub mod exit; 60 pub mod fork; 61 pub mod idle; 62 pub mod kthread; 63 pub mod pid; 64 pub mod process; 65 pub mod resource; 66 pub mod syscall; 67 68 /// 系统中所有进程的pcb 69 static ALL_PROCESS: SpinLock<Option<HashMap<Pid, Arc<ProcessControlBlock>>>> = SpinLock::new(None); 70 71 pub static mut SWITCH_RESULT: Option<PerCpuVar<SwitchResult>> = None; 72 73 /// 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 74 static mut __PROCESS_MANAGEMENT_INIT_DONE: bool = false; 75 76 #[derive(Debug)] 77 pub struct SwitchResult { 78 pub prev_pcb: Option<Arc<ProcessControlBlock>>, 79 pub next_pcb: Option<Arc<ProcessControlBlock>>, 80 } 81 82 impl SwitchResult { 83 pub fn new() -> Self { 84 Self { 85 prev_pcb: None, 86 next_pcb: None, 87 } 88 } 89 } 90 91 #[derive(Debug)] 92 pub struct ProcessManager; 93 impl ProcessManager { 94 fn init() { 95 static INIT_FLAG: AtomicBool = AtomicBool::new(false); 96 if INIT_FLAG 97 .compare_exchange(false, true, Ordering::SeqCst, Ordering::SeqCst) 98 .is_err() 99 { 100 panic!("ProcessManager has been initialized!"); 101 } 102 103 unsafe { 104 compiler_fence(Ordering::SeqCst); 105 kdebug!("To create address space for INIT process."); 106 // test_buddy(); 107 set_INITIAL_PROCESS_ADDRESS_SPACE( 108 AddressSpace::new(true).expect("Failed to create address space for INIT process."), 109 ); 110 kdebug!("INIT process address space created."); 111 compiler_fence(Ordering::SeqCst); 112 }; 113 114 ALL_PROCESS.lock_irqsave().replace(HashMap::new()); 115 Self::arch_init(); 116 kdebug!("process arch init done."); 117 Self::init_idle(); 118 kdebug!("process idle init done."); 119 120 unsafe { __PROCESS_MANAGEMENT_INIT_DONE = true }; 121 kinfo!("Process Manager initialized."); 122 } 123 124 /// 判断进程管理器是否已经初始化完成 125 pub fn initialized() -> bool { 126 unsafe { __PROCESS_MANAGEMENT_INIT_DONE } 127 } 128 129 /// 获取当前进程的pcb 130 pub fn current_pcb() -> Arc<ProcessControlBlock> { 131 if unlikely(unsafe { !__PROCESS_MANAGEMENT_INIT_DONE }) { 132 kerror!("unsafe__PROCESS_MANAGEMENT_INIT_DONE == false"); 133 loop { 134 spin_loop(); 135 } 136 } 137 return ProcessControlBlock::arch_current_pcb(); 138 } 139 140 /// 增加当前进程的锁持有计数 141 #[inline(always)] 142 pub fn preempt_disable() { 143 if likely(unsafe { __PROCESS_MANAGEMENT_INIT_DONE }) { 144 ProcessManager::current_pcb().preempt_disable(); 145 } 146 } 147 148 /// 减少当前进程的锁持有计数 149 #[inline(always)] 150 pub fn preempt_enable() { 151 if likely(unsafe { __PROCESS_MANAGEMENT_INIT_DONE }) { 152 ProcessManager::current_pcb().preempt_enable(); 153 } 154 } 155 156 /// 根据pid获取进程的pcb 157 /// 158 /// ## 参数 159 /// 160 /// - `pid` : 进程的pid 161 /// 162 /// ## 返回值 163 /// 164 /// 如果找到了对应的进程，那么返回该进程的pcb，否则返回None 165 pub fn find(pid: Pid) -> Option<Arc<ProcessControlBlock>> { 166 return ALL_PROCESS.lock_irqsave().as_ref()?.get(&pid).cloned(); 167 } 168 169 /// 向系统中添加一个进程的pcb 170 /// 171 /// ## 参数 172 /// 173 /// - `pcb` : 进程的pcb 174 /// 175 /// ## 返回值 176 /// 177 /// 无 178 pub fn add_pcb(pcb: Arc<ProcessControlBlock>) { 179 ALL_PROCESS 180 .lock_irqsave() 181 .as_mut() 182 .unwrap() 183 .insert(pcb.pid(), pcb.clone()); 184 } 185 186 /// 唤醒一个进程 187 pub fn wakeup(pcb: &Arc<ProcessControlBlock>) -> Result<(), SystemError> { 188 let _guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 189 let state = pcb.sched_info().inner_lock_read_irqsave().state(); 190 if state.is_blocked() { 191 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 192 let state = writer.state(); 193 if state.is_blocked() { 194 writer.set_state(ProcessState::Runnable); 195 // avoid deadlock 196 drop(writer); 197 198 sched_enqueue(pcb.clone(), true); 199 return Ok(()); 200 } else if state.is_exited() { 201 return Err(SystemError::EINVAL); 202 } else { 203 return Ok(()); 204 } 205 } else if state.is_exited() { 206 return Err(SystemError::EINVAL); 207 } else { 208 return Ok(()); 209 } 210 } 211 212 /// 唤醒暂停的进程 213 pub fn wakeup_stop(pcb: &Arc<ProcessControlBlock>) -> Result<(), SystemError> { 214 let _guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 215 let state = pcb.sched_info().inner_lock_read_irqsave().state(); 216 if let ProcessState::Stopped = state { 217 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 218 let state = writer.state(); 219 if let ProcessState::Stopped = state { 220 writer.set_state(ProcessState::Runnable); 221 // avoid deadlock 222 drop(writer); 223 224 sched_enqueue(pcb.clone(), true); 225 return Ok(()); 226 } else if state.is_runnable() { 227 return Ok(()); 228 } else { 229 return Err(SystemError::EINVAL); 230 } 231 } else if state.is_runnable() { 232 return Ok(()); 233 } else { 234 return Err(SystemError::EINVAL); 235 } 236 } 237 238 /// 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 239 /// 240 /// ## 注意 241 /// 242 /// - 进入当前函数之前，不能持有sched_info的锁 243 /// - 进入当前函数之前，必须关闭中断 244 /// - 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 245 pub fn mark_sleep(interruptable: bool) -> Result<(), SystemError> { 246 assert_eq!( 247 CurrentIrqArch::is_irq_enabled(), 248 false, 249 "interrupt must be disabled before enter ProcessManager::mark_sleep()" 250 ); 251 252 let pcb = ProcessManager::current_pcb(); 253 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 254 if !matches!(writer.state(), ProcessState::Exited(_)) { 255 writer.set_state(ProcessState::Blocked(interruptable)); 256 pcb.flags().insert(ProcessFlags::NEED_SCHEDULE); 257 drop(writer); 258 259 return Ok(()); 260 } 261 return Err(SystemError::EINTR); 262 } 263 264 /// 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 265 /// 266 /// ## 注意 267 /// 268 /// - 进入当前函数之前，不能持有sched_info的锁 269 /// - 进入当前函数之前，必须关闭中断 270 pub fn mark_stop() -> Result<(), SystemError> { 271 assert_eq!( 272 CurrentIrqArch::is_irq_enabled(), 273 false, 274 "interrupt must be disabled before enter ProcessManager::mark_stop()" 275 ); 276 277 let pcb = ProcessManager::current_pcb(); 278 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 279 if !matches!(writer.state(), ProcessState::Exited(_)) { 280 writer.set_state(ProcessState::Stopped); 281 pcb.flags().insert(ProcessFlags::NEED_SCHEDULE); 282 drop(writer); 283 284 return Ok(()); 285 } 286 return Err(SystemError::EINTR); 287 } 288 /// 当子进程退出后向父进程发送通知 289 fn exit_notify() { 290 let current = ProcessManager::current_pcb(); 291 // 让INIT进程收养所有子进程 292 if current.pid() != Pid(1) { 293 unsafe { 294 current 295 .adopt_childen() 296 .unwrap_or_else(|e| panic!("adopte_childen failed: error: {e:?}")) 297 }; 298 let r = current.parent_pcb.read().upgrade(); 299 if r.is_none() { 300 return; 301 } 302 let parent_pcb = r.unwrap(); 303 let r = Syscall::kill(parent_pcb.pid(), Signal::SIGCHLD as i32); 304 if r.is_err() { 305 kwarn!( 306 "failed to send kill signal to {:?}'s parent pcb {:?}", 307 current.pid(), 308 parent_pcb.pid() 309 ); 310 } 311 // todo: 这里需要向父进程发送SIGCHLD信号 312 // todo: 这里还需要根据线程组的信息，决定信号的发送 313 } 314 } 315 316 /// 退出当前进程 317 /// 318 /// ## 参数 319 /// 320 /// - `exit_code` : 进程的退出码 321 pub fn exit(exit_code: usize) -> ! { 322 // 关中断 323 unsafe { CurrentIrqArch::interrupt_disable() }; 324 let pcb = ProcessManager::current_pcb(); 325 pcb.sched_info 326 .inner_lock_write_irqsave() 327 .set_state(ProcessState::Exited(exit_code)); 328 pcb.wait_queue.wakeup(Some(ProcessState::Blocked(true))); 329 330 // 进行进程退出后的工作 331 let thread = pcb.thread.write(); 332 if let Some(addr) = thread.set_child_tid { 333 unsafe { clear_user(addr, core::mem::size_of::<i32>()).expect("clear tid failed") }; 334 } 335 336 if let Some(addr) = thread.clear_child_tid { 337 if Arc::strong_count(&pcb.basic().user_vm().expect("User VM Not found")) > 1 { 338 let _ = 339 Futex::futex_wake(addr, FutexFlag::FLAGS_MATCH_NONE, 1, FUTEX_BITSET_MATCH_ANY); 340 } 341 unsafe { clear_user(addr, core::mem::size_of::<i32>()).expect("clear tid failed") }; 342 } 343 344 // 如果是vfork出来的进程，则需要处理completion 345 if thread.vfork_done.is_some() { 346 thread.vfork_done.as_ref().unwrap().complete_all(); 347 } 348 drop(thread); 349 unsafe { pcb.basic_mut().set_user_vm(None) }; 350 drop(pcb); 351 ProcessManager::exit_notify(); 352 unsafe { CurrentIrqArch::interrupt_enable() }; 353 354 sched(); 355 loop {} 356 } 357 358 pub unsafe fn release(pid: Pid) { 359 let pcb = ProcessManager::find(pid); 360 if !pcb.is_none() { 361 // let pcb = pcb.unwrap(); 362 // 判断该pcb是否在全局没有任何引用 363 // 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。 364 // 因此目前暂时注释掉，使得能跑 365 // if Arc::strong_count(&pcb) <= 2 { 366 // drop(pcb); 367 // ALL_PROCESS.lock().as_mut().unwrap().remove(&pid); 368 // } else { 369 // // 如果不为1就panic 370 // let msg = format!("pcb '{:?}' is still referenced, strong count={}",pcb.pid(), Arc::strong_count(&pcb)); 371 // kerror!("{}", msg); 372 // panic!() 373 // } 374 375 ALL_PROCESS.lock_irqsave().as_mut().unwrap().remove(&pid); 376 } 377 } 378 379 /// 上下文切换完成后的钩子函数 380 unsafe fn switch_finish_hook() { 381 // kdebug!("switch_finish_hook"); 382 let prev_pcb = SWITCH_RESULT 383 .as_mut() 384 .unwrap() 385 .get_mut() 386 .prev_pcb 387 .take() 388 .expect("prev_pcb is None"); 389 let next_pcb = SWITCH_RESULT 390 .as_mut() 391 .unwrap() 392 .get_mut() 393 .next_pcb 394 .take() 395 .expect("next_pcb is None"); 396 397 // 由于进程切换前使用了SpinLockGuard::leak()，所以这里需要手动释放锁 398 prev_pcb.arch_info.force_unlock(); 399 next_pcb.arch_info.force_unlock(); 400 } 401 402 /// 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 403 /// 404 /// ## 参数 405 /// 406 /// - `pcb` : 进程的pcb 407 #[allow(dead_code)] 408 pub fn kick(pcb: &Arc<ProcessControlBlock>) { 409 ProcessManager::current_pcb().preempt_disable(); 410 let cpu_id = pcb.sched_info().on_cpu(); 411 412 if let Some(cpu_id) = cpu_id { 413 let cpu_id = cpu_id; 414 415 if pcb.pid() == CPU_EXECUTING.get(cpu_id) { 416 kick_cpu(cpu_id).expect("ProcessManager::kick(): Failed to kick cpu"); 417 } 418 } 419 420 ProcessManager::current_pcb().preempt_enable(); 421 } 422 } 423 424 /// 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 425 #[cfg(target_arch = "x86_64")] 426 pub unsafe extern "sysv64" fn switch_finish_hook() { 427 ProcessManager::switch_finish_hook(); 428 } 429 #[cfg(target_arch = "riscv64")] 430 pub unsafe extern "C" fn switch_finish_hook() { 431 ProcessManager::switch_finish_hook(); 432 } 433 434 int_like!(Pid, AtomicPid, usize, AtomicUsize); 435 436 impl Hash for Pid { 437 fn hash<H: Hasher>(&self, state: &mut H) { 438 self.0.hash(state); 439 } 440 } 441 442 impl Pid { 443 pub fn to_string(&self) -> String { 444 self.0.to_string() 445 } 446 } 447 448 #[derive(Debug, Clone, Copy, PartialEq, Eq)] 449 pub enum ProcessState { 450 /// The process is running on a CPU or in a run queue. 451 Runnable, 452 /// The process is waiting for an event to occur. 453 /// 其中的bool表示该等待过程是否可以被打断。 454 /// - 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。 455 /// - 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。 456 Blocked(bool), 457 /// 进程被信号终止 458 Stopped, 459 /// 进程已经退出，usize表示进程的退出码 460 Exited(usize), 461 } 462 463 #[allow(dead_code)] 464 impl ProcessState { 465 #[inline(always)] 466 pub fn is_runnable(&self) -> bool { 467 return matches!(self, ProcessState::Runnable); 468 } 469 470 #[inline(always)] 471 pub fn is_blocked(&self) -> bool { 472 return matches!(self, ProcessState::Blocked(_)); 473 } 474 475 #[inline(always)] 476 pub fn is_blocked_interruptable(&self) -> bool { 477 return matches!(self, ProcessState::Blocked(true)); 478 } 479 480 /// Returns `true` if the process state is [`Exited`]. 481 #[inline(always)] 482 pub fn is_exited(&self) -> bool { 483 return matches!(self, ProcessState::Exited(_)); 484 } 485 486 /// Returns `true` if the process state is [`Stopped`]. 487 /// 488 /// [`Stopped`]: ProcessState::Stopped 489 #[inline(always)] 490 pub fn is_stopped(&self) -> bool { 491 matches!(self, ProcessState::Stopped) 492 } 493 494 /// Returns exit code if the process state is [`Exited`]. 495 #[inline(always)] 496 pub fn exit_code(&self) -> Option<usize> { 497 match self { 498 ProcessState::Exited(code) => Some(*code), 499 _ => None, 500 } 501 } 502 } 503 504 bitflags! { 505 /// pcb的标志位 506 pub struct ProcessFlags: usize { 507 /// 当前pcb表示一个内核线程 508 const KTHREAD = 1 << 0; 509 /// 当前进程需要被调度 510 const NEED_SCHEDULE = 1 << 1; 511 /// 进程由于vfork而与父进程存在资源共享 512 const VFORK = 1 << 2; 513 /// 进程不可被冻结 514 const NOFREEZE = 1 << 3; 515 /// 进程正在退出 516 const EXITING = 1 << 4; 517 /// 进程由于接收到终止信号唤醒 518 const WAKEKILL = 1 << 5; 519 /// 进程由于接收到信号而退出.(Killed by a signal) 520 const SIGNALED = 1 << 6; 521 /// 进程需要迁移到其他cpu上 522 const NEED_MIGRATE = 1 << 7; 523 } 524 } 525 526 #[derive(Debug)] 527 pub struct ProcessControlBlock { 528 /// 当前进程的pid 529 pid: Pid, 530 /// 当前进程的线程组id（这个值在同一个线程组内永远不变） 531 tgid: Pid, 532 533 basic: RwLock<ProcessBasicInfo>, 534 /// 当前进程的自旋锁持有计数 535 preempt_count: AtomicUsize, 536 537 flags: LockFreeFlags<ProcessFlags>, 538 worker_private: SpinLock<Option<WorkerPrivate>>, 539 /// 进程的内核栈 540 kernel_stack: RwLock<KernelStack>, 541 542 /// 系统调用栈 543 syscall_stack: RwLock<KernelStack>, 544 545 /// 与调度相关的信息 546 sched_info: ProcessSchedulerInfo, 547 /// 与处理器架构相关的信息 548 arch_info: SpinLock<ArchPCBInfo>, 549 /// 与信号处理相关的信息(似乎可以是无锁的) 550 sig_info: RwLock<ProcessSignalInfo>, 551 /// 信号处理结构体 552 sig_struct: SpinLock<SignalStruct>, 553 /// 退出信号S 554 exit_signal: AtomicSignal, 555 556 /// 父进程指针 557 parent_pcb: RwLock<Weak<ProcessControlBlock>>, 558 /// 真实父进程指针 559 real_parent_pcb: RwLock<Weak<ProcessControlBlock>>, 560 561 /// 子进程链表 562 children: RwLock<Vec<Pid>>, 563 564 /// 等待队列 565 wait_queue: WaitQueue, 566 567 /// 线程信息 568 thread: RwLock<ThreadInfo>, 569 } 570 571 impl ProcessControlBlock { 572 /// Generate a new pcb. 573 /// 574 /// ## 参数 575 /// 576 /// - `name` : 进程的名字 577 /// - `kstack` : 进程的内核栈 578 /// 579 /// ## 返回值 580 /// 581 /// 返回一个新的pcb 582 pub fn new(name: String, kstack: KernelStack) -> Arc<Self> { 583 return Self::do_create_pcb(name, kstack, false); 584 } 585 586 /// 创建一个新的idle进程 587 /// 588 /// 请注意，这个函数只能在进程管理初始化的时候调用。 589 pub fn new_idle(cpu_id: u32, kstack: KernelStack) -> Arc<Self> { 590 let name = format!("idle-{}", cpu_id); 591 return Self::do_create_pcb(name, kstack, true); 592 } 593 594 #[inline(never)] 595 fn do_create_pcb(name: String, kstack: KernelStack, is_idle: bool) -> Arc<Self> { 596 let (pid, ppid, cwd) = if is_idle { 597 (Pid(0), Pid(0), "/".to_string()) 598 } else { 599 let ppid = ProcessManager::current_pcb().pid(); 600 let cwd = ProcessManager::current_pcb().basic().cwd(); 601 (Self::generate_pid(), ppid, cwd) 602 }; 603 604 let basic_info = ProcessBasicInfo::new(Pid(0), ppid, name, cwd, None); 605 let preempt_count = AtomicUsize::new(0); 606 let flags = unsafe { LockFreeFlags::new(ProcessFlags::empty()) }; 607 608 let sched_info = ProcessSchedulerInfo::new(None); 609 let arch_info = SpinLock::new(ArchPCBInfo::new(&kstack)); 610 611 let ppcb: Weak<ProcessControlBlock> = ProcessManager::find(ppid) 612 .map(|p| Arc::downgrade(&p)) 613 .unwrap_or_else(|| Weak::new()); 614 615 let pcb = Self { 616 pid, 617 tgid: pid, 618 basic: basic_info, 619 preempt_count, 620 flags, 621 kernel_stack: RwLock::new(kstack), 622 syscall_stack: RwLock::new(KernelStack::new().unwrap()), 623 worker_private: SpinLock::new(None), 624 sched_info, 625 arch_info, 626 sig_info: RwLock::new(ProcessSignalInfo::default()), 627 sig_struct: SpinLock::new(SignalStruct::new()), 628 exit_signal: AtomicSignal::new(Signal::SIGCHLD), 629 parent_pcb: RwLock::new(ppcb.clone()), 630 real_parent_pcb: RwLock::new(ppcb), 631 children: RwLock::new(Vec::new()), 632 wait_queue: WaitQueue::INIT, 633 thread: RwLock::new(ThreadInfo::new()), 634 }; 635 636 // 初始化系统调用栈 637 #[cfg(target_arch = "x86_64")] 638 pcb.arch_info 639 .lock() 640 .init_syscall_stack(&pcb.syscall_stack.read()); 641 642 let pcb = Arc::new(pcb); 643 644 // 设置进程的arc指针到内核栈和系统调用栈的最低地址处 645 unsafe { 646 pcb.kernel_stack 647 .write() 648 .set_pcb(Arc::downgrade(&pcb)) 649 .unwrap(); 650 651 pcb.syscall_stack 652 .write() 653 .set_pcb(Arc::downgrade(&pcb)) 654 .unwrap() 655 }; 656 657 // 将当前pcb加入父进程的子进程哈希表中 658 if pcb.pid() > Pid(1) { 659 if let Some(ppcb_arc) = pcb.parent_pcb.read().upgrade() { 660 let mut children = ppcb_arc.children.write_irqsave(); 661 children.push(pcb.pid()); 662 } else { 663 panic!("parent pcb is None"); 664 } 665 } 666 667 return pcb; 668 } 669 670 /// 生成一个新的pid 671 #[inline(always)] 672 fn generate_pid() -> Pid { 673 static NEXT_PID: AtomicPid = AtomicPid::new(Pid(1)); 674 return NEXT_PID.fetch_add(Pid(1), Ordering::SeqCst); 675 } 676 677 /// 返回当前进程的锁持有计数 678 #[inline(always)] 679 pub fn preempt_count(&self) -> usize { 680 return self.preempt_count.load(Ordering::SeqCst); 681 } 682 683 /// 增加当前进程的锁持有计数 684 #[inline(always)] 685 pub fn preempt_disable(&self) { 686 self.preempt_count.fetch_add(1, Ordering::SeqCst); 687 } 688 689 /// 减少当前进程的锁持有计数 690 #[inline(always)] 691 pub fn preempt_enable(&self) { 692 self.preempt_count.fetch_sub(1, Ordering::SeqCst); 693 } 694 695 #[inline(always)] 696 pub unsafe fn set_preempt_count(&self, count: usize) { 697 self.preempt_count.store(count, Ordering::SeqCst); 698 } 699 700 #[inline(always)] 701 pub fn flags(&self) -> &mut ProcessFlags { 702 return self.flags.get_mut(); 703 } 704 705 /// 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 706 /// 否则会导致死锁 707 #[inline(always)] 708 pub fn basic(&self) -> RwLockReadGuard<ProcessBasicInfo> { 709 return self.basic.read(); 710 } 711 712 #[inline(always)] 713 pub fn set_name(&self, name: String) { 714 self.basic.write().set_name(name); 715 } 716 717 #[inline(always)] 718 pub fn basic_mut(&self) -> RwLockWriteGuard<ProcessBasicInfo> { 719 return self.basic.write_irqsave(); 720 } 721 722 /// # 获取arch info的锁，同时关闭中断 723 #[inline(always)] 724 pub fn arch_info_irqsave(&self) -> SpinLockGuard<ArchPCBInfo> { 725 return self.arch_info.lock_irqsave(); 726 } 727 728 /// # 获取arch info的锁，但是不关闭中断 729 /// 730 /// 由于arch info在进程切换的时候会使用到， 731 /// 因此在中断上下文外，获取arch info 而不irqsave是不安全的. 732 /// 733 /// 只能在以下情况下使用这个函数： 734 /// - 在中断上下文中（中断已经禁用），获取arch info的锁。 735 /// - 刚刚创建新的pcb 736 #[inline(always)] 737 pub unsafe fn arch_info(&self) -> SpinLockGuard<ArchPCBInfo> { 738 return self.arch_info.lock(); 739 } 740 741 #[inline(always)] 742 pub fn kernel_stack(&self) -> RwLockReadGuard<KernelStack> { 743 return self.kernel_stack.read(); 744 } 745 746 #[inline(always)] 747 #[allow(dead_code)] 748 pub fn kernel_stack_mut(&self) -> RwLockWriteGuard<KernelStack> { 749 return self.kernel_stack.write(); 750 } 751 752 #[inline(always)] 753 pub fn sched_info(&self) -> &ProcessSchedulerInfo { 754 return &self.sched_info; 755 } 756 757 #[inline(always)] 758 pub fn worker_private(&self) -> SpinLockGuard<Option<WorkerPrivate>> { 759 return self.worker_private.lock(); 760 } 761 762 #[inline(always)] 763 pub fn pid(&self) -> Pid { 764 return self.pid; 765 } 766 767 #[inline(always)] 768 pub fn tgid(&self) -> Pid { 769 return self.tgid; 770 } 771 772 /// 获取文件描述符表的Arc指针 773 #[inline(always)] 774 pub fn fd_table(&self) -> Arc<RwLock<FileDescriptorVec>> { 775 return self.basic.read().fd_table().unwrap(); 776 } 777 778 /// 根据文件描述符序号，获取socket对象的Arc指针 779 /// 780 /// ## 参数 781 /// 782 /// - `fd` 文件描述符序号 783 /// 784 /// ## 返回值 785 /// 786 /// 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 787 pub fn get_socket(&self, fd: i32) -> Option<Arc<SocketInode>> { 788 let binding = ProcessManager::current_pcb().fd_table(); 789 let fd_table_guard = binding.read(); 790 791 let f = fd_table_guard.get_file_by_fd(fd)?; 792 drop(fd_table_guard); 793 794 let guard = f.lock(); 795 if guard.file_type() != FileType::Socket { 796 return None; 797 } 798 let socket: Arc<SocketInode> = guard 799 .inode() 800 .downcast_arc::<SocketInode>() 801 .expect("Not a socket inode"); 802 return Some(socket); 803 } 804 805 /// 当前进程退出时,让初始进程收养所有子进程 806 unsafe fn adopt_childen(&self) -> Result<(), SystemError> { 807 match ProcessManager::find(Pid(1)) { 808 Some(init_pcb) => { 809 let childen_guard = self.children.write(); 810 let mut init_childen_guard = init_pcb.children.write(); 811 812 childen_guard.iter().for_each(|pid| { 813 init_childen_guard.push(*pid); 814 }); 815 816 return Ok(()); 817 } 818 _ => Err(SystemError::ECHILD), 819 } 820 } 821 822 /// 生成进程的名字 823 pub fn generate_name(program_path: &str, args: &Vec<String>) -> String { 824 let mut name = program_path.to_string(); 825 for arg in args { 826 name.push(' '); 827 name.push_str(arg); 828 } 829 return name; 830 } 831 832 pub fn sig_info(&self) -> RwLockReadGuard<ProcessSignalInfo> { 833 self.sig_info.read() 834 } 835 836 pub fn sig_info_irqsave(&self) -> RwLockReadGuard<ProcessSignalInfo> { 837 self.sig_info.read_irqsave() 838 } 839 840 pub fn try_siginfo(&self, times: u8) -> Option<RwLockReadGuard<ProcessSignalInfo>> { 841 for _ in 0..times { 842 if let Some(r) = self.sig_info.try_read() { 843 return Some(r); 844 } 845 } 846 847 return None; 848 } 849 850 pub fn sig_info_mut(&self) -> RwLockWriteGuard<ProcessSignalInfo> { 851 self.sig_info.write_irqsave() 852 } 853 854 pub fn try_siginfo_mut(&self, times: u8) -> Option<RwLockWriteGuard<ProcessSignalInfo>> { 855 for _ in 0..times { 856 if let Some(r) = self.sig_info.try_write() { 857 return Some(r); 858 } 859 } 860 861 return None; 862 } 863 864 pub fn sig_struct(&self) -> SpinLockGuard<SignalStruct> { 865 self.sig_struct.lock() 866 } 867 868 pub fn try_sig_struct_irq(&self, times: u8) -> Option<SpinLockGuard<SignalStruct>> { 869 for _ in 0..times { 870 if let Ok(r) = self.sig_struct.try_lock_irqsave() { 871 return Some(r); 872 } 873 } 874 875 return None; 876 } 877 878 pub fn sig_struct_irqsave(&self) -> SpinLockGuard<SignalStruct> { 879 self.sig_struct.lock_irqsave() 880 } 881 } 882 883 impl Drop for ProcessControlBlock { 884 fn drop(&mut self) { 885 // 在ProcFS中,解除进程的注册 886 procfs_unregister_pid(self.pid()) 887 .unwrap_or_else(|e| panic!("procfs_unregister_pid failed: error: {e:?}")); 888 889 if let Some(ppcb) = self.parent_pcb.read().upgrade() { 890 ppcb.children.write().retain(|pid| *pid != self.pid()); 891 } 892 } 893 } 894 895 /// 线程信息 896 #[derive(Debug)] 897 pub struct ThreadInfo { 898 // 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 899 clear_child_tid: Option<VirtAddr>, 900 set_child_tid: Option<VirtAddr>, 901 902 vfork_done: Option<Arc<Completion>>, 903 /// 线程组的组长 904 group_leader: Weak<ProcessControlBlock>, 905 } 906 907 impl ThreadInfo { 908 pub fn new() -> Self { 909 Self { 910 clear_child_tid: None, 911 set_child_tid: None, 912 vfork_done: None, 913 group_leader: Weak::default(), 914 } 915 } 916 917 pub fn group_leader(&self) -> Option<Arc<ProcessControlBlock>> { 918 return self.group_leader.upgrade(); 919 } 920 } 921 922 /// 进程的基本信息 923 /// 924 /// 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。 925 #[derive(Debug)] 926 pub struct ProcessBasicInfo { 927 /// 当前进程的进程组id 928 pgid: Pid, 929 /// 当前进程的父进程的pid 930 ppid: Pid, 931 /// 进程的名字 932 name: String, 933 934 /// 当前进程的工作目录 935 cwd: String, 936 937 /// 用户地址空间 938 user_vm: Option<Arc<AddressSpace>>, 939 940 /// 文件描述符表 941 fd_table: Option<Arc<RwLock<FileDescriptorVec>>>, 942 } 943 944 impl ProcessBasicInfo { 945 #[inline(never)] 946 pub fn new( 947 pgid: Pid, 948 ppid: Pid, 949 name: String, 950 cwd: String, 951 user_vm: Option<Arc<AddressSpace>>, 952 ) -> RwLock<Self> { 953 let fd_table = Arc::new(RwLock::new(FileDescriptorVec::new())); 954 return RwLock::new(Self { 955 pgid, 956 ppid, 957 name, 958 cwd, 959 user_vm, 960 fd_table: Some(fd_table), 961 }); 962 } 963 964 pub fn pgid(&self) -> Pid { 965 return self.pgid; 966 } 967 968 pub fn ppid(&self) -> Pid { 969 return self.ppid; 970 } 971 972 pub fn name(&self) -> &str { 973 return &self.name; 974 } 975 976 pub fn set_name(&mut self, name: String) { 977 self.name = name; 978 } 979 980 pub fn cwd(&self) -> String { 981 return self.cwd.clone(); 982 } 983 pub fn set_cwd(&mut self, path: String) { 984 return self.cwd = path; 985 } 986 987 pub fn user_vm(&self) -> Option<Arc<AddressSpace>> { 988 return self.user_vm.clone(); 989 } 990 991 pub unsafe fn set_user_vm(&mut self, user_vm: Option<Arc<AddressSpace>>) { 992 self.user_vm = user_vm; 993 } 994 995 pub fn fd_table(&self) -> Option<Arc<RwLock<FileDescriptorVec>>> { 996 return self.fd_table.clone(); 997 } 998 999 pub fn set_fd_table(&mut self, fd_table: Option<Arc<RwLock<FileDescriptorVec>>>) { 1000 self.fd_table = fd_table; 1001 } 1002 } 1003 1004 #[derive(Debug)] 1005 pub struct ProcessSchedulerInfo { 1006 /// 当前进程所在的cpu 1007 on_cpu: AtomicI32, 1008 /// 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）， 1009 /// 该字段存储要被迁移到的目标处理器核心号 1010 migrate_to: AtomicI32, 1011 inner_locked: RwLock<InnerSchedInfo>, 1012 /// 进程的调度优先级 1013 priority: SchedPriority, 1014 /// 当前进程的虚拟运行时间 1015 virtual_runtime: AtomicIsize, 1016 /// 由实时调度器管理的时间片 1017 rt_time_slice: AtomicIsize, 1018 } 1019 1020 #[derive(Debug)] 1021 pub struct InnerSchedInfo { 1022 /// 当前进程的状态 1023 state: ProcessState, 1024 /// 进程的调度策略 1025 sched_policy: SchedPolicy, 1026 } 1027 1028 impl InnerSchedInfo { 1029 pub fn state(&self) -> ProcessState { 1030 return self.state; 1031 } 1032 1033 pub fn set_state(&mut self, state: ProcessState) { 1034 self.state = state; 1035 } 1036 1037 pub fn policy(&self) -> SchedPolicy { 1038 return self.sched_policy; 1039 } 1040 } 1041 1042 impl ProcessSchedulerInfo { 1043 #[inline(never)] 1044 pub fn new(on_cpu: Option<u32>) -> Self { 1045 let cpu_id = match on_cpu { 1046 Some(cpu_id) => cpu_id as i32, 1047 None => -1, 1048 }; 1049 return Self { 1050 on_cpu: AtomicI32::new(cpu_id), 1051 migrate_to: AtomicI32::new(-1), 1052 inner_locked: RwLock::new(InnerSchedInfo { 1053 state: ProcessState::Blocked(false), 1054 sched_policy: SchedPolicy::CFS, 1055 }), 1056 virtual_runtime: AtomicIsize::new(0), 1057 rt_time_slice: AtomicIsize::new(0), 1058 priority: SchedPriority::new(100).unwrap(), 1059 }; 1060 } 1061 1062 pub fn on_cpu(&self) -> Option<u32> { 1063 let on_cpu = self.on_cpu.load(Ordering::SeqCst); 1064 if on_cpu == -1 { 1065 return None; 1066 } else { 1067 return Some(on_cpu as u32); 1068 } 1069 } 1070 1071 pub fn set_on_cpu(&self, on_cpu: Option<u32>) { 1072 if let Some(cpu_id) = on_cpu { 1073 self.on_cpu.store(cpu_id as i32, Ordering::SeqCst); 1074 } else { 1075 self.on_cpu.store(-1, Ordering::SeqCst); 1076 } 1077 } 1078 1079 pub fn migrate_to(&self) -> Option<u32> { 1080 let migrate_to = self.migrate_to.load(Ordering::SeqCst); 1081 if migrate_to == -1 { 1082 return None; 1083 } else { 1084 return Some(migrate_to as u32); 1085 } 1086 } 1087 1088 pub fn set_migrate_to(&self, migrate_to: Option<u32>) { 1089 if let Some(data) = migrate_to { 1090 self.migrate_to.store(data as i32, Ordering::SeqCst); 1091 } else { 1092 self.migrate_to.store(-1, Ordering::SeqCst) 1093 } 1094 } 1095 1096 pub fn inner_lock_write_irqsave(&self) -> RwLockWriteGuard<InnerSchedInfo> { 1097 return self.inner_locked.write_irqsave(); 1098 } 1099 1100 pub fn inner_lock_read_irqsave(&self) -> RwLockReadGuard<InnerSchedInfo> { 1101 return self.inner_locked.read_irqsave(); 1102 } 1103 1104 pub fn inner_lock_try_read_irqsave( 1105 &self, 1106 times: u8, 1107 ) -> Option<RwLockReadGuard<InnerSchedInfo>> { 1108 for _ in 0..times { 1109 if let Some(r) = self.inner_locked.try_read_irqsave() { 1110 return Some(r); 1111 } 1112 } 1113 1114 return None; 1115 } 1116 1117 pub fn inner_lock_try_upgradable_read_irqsave( 1118 &self, 1119 times: u8, 1120 ) -> Option<RwLockUpgradableGuard<InnerSchedInfo>> { 1121 for _ in 0..times { 1122 if let Some(r) = self.inner_locked.try_upgradeable_read_irqsave() { 1123 return Some(r); 1124 } 1125 } 1126 1127 return None; 1128 } 1129 1130 pub fn virtual_runtime(&self) -> isize { 1131 return self.virtual_runtime.load(Ordering::SeqCst); 1132 } 1133 1134 pub fn set_virtual_runtime(&self, virtual_runtime: isize) { 1135 self.virtual_runtime 1136 .store(virtual_runtime, Ordering::SeqCst); 1137 } 1138 pub fn increase_virtual_runtime(&self, delta: isize) { 1139 self.virtual_runtime.fetch_add(delta, Ordering::SeqCst); 1140 } 1141 1142 pub fn rt_time_slice(&self) -> isize { 1143 return self.rt_time_slice.load(Ordering::SeqCst); 1144 } 1145 1146 pub fn set_rt_time_slice(&self, rt_time_slice: isize) { 1147 self.rt_time_slice.store(rt_time_slice, Ordering::SeqCst); 1148 } 1149 1150 pub fn increase_rt_time_slice(&self, delta: isize) { 1151 self.rt_time_slice.fetch_add(delta, Ordering::SeqCst); 1152 } 1153 1154 pub fn priority(&self) -> SchedPriority { 1155 return self.priority; 1156 } 1157 } 1158 1159 #[derive(Debug, Clone)] 1160 pub struct KernelStack { 1161 stack: Option<AlignedBox<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>>, 1162 /// 标记该内核栈是否可以被释放 1163 can_be_freed: bool, 1164 } 1165 1166 impl KernelStack { 1167 pub const SIZE: usize = 0x4000; 1168 pub const ALIGN: usize = 0x4000; 1169 1170 pub fn new() -> Result<Self, SystemError> { 1171 return Ok(Self { 1172 stack: Some( 1173 AlignedBox::<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>::new_zeroed()?, 1174 ), 1175 can_be_freed: true, 1176 }); 1177 } 1178 1179 /// 根据已有的空间，构造一个内核栈结构体 1180 /// 1181 /// 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！ 1182 pub unsafe fn from_existed(base: VirtAddr) -> Result<Self, SystemError> { 1183 if base.is_null() || base.check_aligned(Self::ALIGN) == false { 1184 return Err(SystemError::EFAULT); 1185 } 1186 1187 return Ok(Self { 1188 stack: Some( 1189 AlignedBox::<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>::new_unchecked( 1190 base.data() as *mut [u8; KernelStack::SIZE], 1191 ), 1192 ), 1193 can_be_freed: false, 1194 }); 1195 } 1196 1197 /// 返回内核栈的起始虚拟地址(低地址) 1198 pub fn start_address(&self) -> VirtAddr { 1199 return VirtAddr::new(self.stack.as_ref().unwrap().as_ptr() as usize); 1200 } 1201 1202 /// 返回内核栈的结束虚拟地址(高地址)(不包含该地址) 1203 pub fn stack_max_address(&self) -> VirtAddr { 1204 return VirtAddr::new(self.stack.as_ref().unwrap().as_ptr() as usize + Self::SIZE); 1205 } 1206 1207 pub unsafe fn set_pcb(&mut self, pcb: Weak<ProcessControlBlock>) -> Result<(), SystemError> { 1208 // 将一个Weak<ProcessControlBlock>放到内核栈的最低地址处 1209 let p: *const ProcessControlBlock = Weak::into_raw(pcb); 1210 let stack_bottom_ptr = self.start_address().data() as *mut *const ProcessControlBlock; 1211 1212 // 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 1213 if unlikely(unsafe { !(*stack_bottom_ptr).is_null() }) { 1214 kerror!("kernel stack bottom is not null: {:p}", *stack_bottom_ptr); 1215 return Err(SystemError::EPERM); 1216 } 1217 // 将pcb的地址放到内核栈的最低地址处 1218 unsafe { 1219 *stack_bottom_ptr = p; 1220 } 1221 1222 return Ok(()); 1223 } 1224 1225 /// 清除内核栈的pcb指针 1226 /// 1227 /// ## 参数 1228 /// 1229 /// - `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 1230 pub unsafe fn clear_pcb(&mut self, force: bool) { 1231 let stack_bottom_ptr = self.start_address().data() as *mut *const ProcessControlBlock; 1232 if unlikely(unsafe { (*stack_bottom_ptr).is_null() }) { 1233 return; 1234 } 1235 1236 if !force { 1237 let pcb_ptr: Weak<ProcessControlBlock> = Weak::from_raw(*stack_bottom_ptr); 1238 drop(pcb_ptr); 1239 } 1240 1241 *stack_bottom_ptr = core::ptr::null(); 1242 } 1243 1244 /// 返回指向当前内核栈pcb的Arc指针 1245 #[allow(dead_code)] 1246 pub unsafe fn pcb(&self) -> Option<Arc<ProcessControlBlock>> { 1247 // 从内核栈的最低地址处取出pcb的地址 1248 let p = self.stack.as_ref().unwrap().as_ptr() as *const *const ProcessControlBlock; 1249 if unlikely(unsafe { (*p).is_null() }) { 1250 return None; 1251 } 1252 1253 // 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 1254 let weak_wrapper: ManuallyDrop<Weak<ProcessControlBlock>> = 1255 ManuallyDrop::new(Weak::from_raw(*p)); 1256 1257 let new_arc: Arc<ProcessControlBlock> = weak_wrapper.upgrade()?; 1258 return Some(new_arc); 1259 } 1260 } 1261 1262 impl Drop for KernelStack { 1263 fn drop(&mut self) { 1264 if !self.stack.is_none() { 1265 let ptr = self.stack.as_ref().unwrap().as_ptr() as *const *const ProcessControlBlock; 1266 if unsafe { !(*ptr).is_null() } { 1267 let pcb_ptr: Weak<ProcessControlBlock> = unsafe { Weak::from_raw(*ptr) }; 1268 drop(pcb_ptr); 1269 } 1270 } 1271 // 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 1272 if !self.can_be_freed { 1273 let bx = self.stack.take(); 1274 core::mem::forget(bx); 1275 } 1276 } 1277 } 1278 1279 pub fn process_init() { 1280 ProcessManager::init(); 1281 } 1282 1283 #[derive(Debug)] 1284 pub struct ProcessSignalInfo { 1285 // 当前进程 1286 sig_block: SigSet, 1287 // sig_pending 中存储当前线程要处理的信号 1288 sig_pending: SigPending, 1289 // sig_shared_pending 中存储当前线程所属进程要处理的信号 1290 sig_shared_pending: SigPending, 1291 } 1292 1293 impl ProcessSignalInfo { 1294 pub fn sig_block(&self) -> &SigSet { 1295 &self.sig_block 1296 } 1297 1298 pub fn sig_pending(&self) -> &SigPending { 1299 &self.sig_pending 1300 } 1301 1302 pub fn sig_pending_mut(&mut self) -> &mut SigPending { 1303 &mut self.sig_pending 1304 } 1305 1306 pub fn sig_block_mut(&mut self) -> &mut SigSet { 1307 &mut self.sig_block 1308 } 1309 1310 pub fn sig_shared_pending_mut(&mut self) -> &mut SigPending { 1311 &mut self.sig_shared_pending 1312 } 1313 1314 pub fn sig_shared_pending(&self) -> &SigPending { 1315 &self.sig_shared_pending 1316 } 1317 1318 /// 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 1319 /// 1320 /// ## 参数 1321 /// 1322 /// - `sig_mask` 被忽略掉的信号 1323 /// 1324 pub fn dequeue_signal(&mut self, sig_mask: &SigSet) -> (Signal, Option<SigInfo>) { 1325 let res = self.sig_pending.dequeue_signal(sig_mask); 1326 if res.0 != Signal::INVALID { 1327 return res; 1328 } else { 1329 return self.sig_shared_pending.dequeue_signal(sig_mask); 1330 } 1331 } 1332 } 1333 1334 impl Default for ProcessSignalInfo { 1335 fn default() -> Self { 1336 Self { 1337 sig_block: SigSet::empty(), 1338 sig_pending: SigPending::default(), 1339 sig_shared_pending: SigPending::default(), 1340 } 1341 } 1342 } 1343