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 init; 63 pub mod kthread; 64 pub mod pid; 65 pub mod process; 66 pub mod resource; 67 pub mod syscall; 68 69 /// 系统中所有进程的pcb 70 static ALL_PROCESS: SpinLock<Option<HashMap<Pid, Arc<ProcessControlBlock>>>> = SpinLock::new(None); 71 72 pub static mut SWITCH_RESULT: Option<PerCpuVar<SwitchResult>> = None; 73 74 /// 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 75 static mut __PROCESS_MANAGEMENT_INIT_DONE: bool = false; 76 77 #[derive(Debug)] 78 pub struct SwitchResult { 79 pub prev_pcb: Option<Arc<ProcessControlBlock>>, 80 pub next_pcb: Option<Arc<ProcessControlBlock>>, 81 } 82 83 impl SwitchResult { 84 pub fn new() -> Self { 85 Self { 86 prev_pcb: None, 87 next_pcb: None, 88 } 89 } 90 } 91 92 #[derive(Debug)] 93 pub struct ProcessManager; 94 impl ProcessManager { 95 fn init() { 96 static INIT_FLAG: AtomicBool = AtomicBool::new(false); 97 if INIT_FLAG 98 .compare_exchange(false, true, Ordering::SeqCst, Ordering::SeqCst) 99 .is_err() 100 { 101 panic!("ProcessManager has been initialized!"); 102 } 103 104 unsafe { 105 compiler_fence(Ordering::SeqCst); 106 kdebug!("To create address space for INIT process."); 107 // test_buddy(); 108 set_INITIAL_PROCESS_ADDRESS_SPACE( 109 AddressSpace::new(true).expect("Failed to create address space for INIT process."), 110 ); 111 kdebug!("INIT process address space created."); 112 compiler_fence(Ordering::SeqCst); 113 }; 114 115 ALL_PROCESS.lock_irqsave().replace(HashMap::new()); 116 Self::arch_init(); 117 kdebug!("process arch init done."); 118 Self::init_idle(); 119 kdebug!("process idle init done."); 120 121 unsafe { __PROCESS_MANAGEMENT_INIT_DONE = true }; 122 kinfo!("Process Manager initialized."); 123 } 124 125 /// 判断进程管理器是否已经初始化完成 126 pub fn initialized() -> bool { 127 unsafe { __PROCESS_MANAGEMENT_INIT_DONE } 128 } 129 130 /// 获取当前进程的pcb 131 pub fn current_pcb() -> Arc<ProcessControlBlock> { 132 if unlikely(unsafe { !__PROCESS_MANAGEMENT_INIT_DONE }) { 133 kerror!("unsafe__PROCESS_MANAGEMENT_INIT_DONE == false"); 134 loop { 135 spin_loop(); 136 } 137 } 138 return ProcessControlBlock::arch_current_pcb(); 139 } 140 141 /// 增加当前进程的锁持有计数 142 #[inline(always)] 143 pub fn preempt_disable() { 144 if likely(unsafe { __PROCESS_MANAGEMENT_INIT_DONE }) { 145 ProcessManager::current_pcb().preempt_disable(); 146 } 147 } 148 149 /// 减少当前进程的锁持有计数 150 #[inline(always)] 151 pub fn preempt_enable() { 152 if likely(unsafe { __PROCESS_MANAGEMENT_INIT_DONE }) { 153 ProcessManager::current_pcb().preempt_enable(); 154 } 155 } 156 157 /// 根据pid获取进程的pcb 158 /// 159 /// ## 参数 160 /// 161 /// - `pid` : 进程的pid 162 /// 163 /// ## 返回值 164 /// 165 /// 如果找到了对应的进程，那么返回该进程的pcb，否则返回None 166 pub fn find(pid: Pid) -> Option<Arc<ProcessControlBlock>> { 167 return ALL_PROCESS.lock_irqsave().as_ref()?.get(&pid).cloned(); 168 } 169 170 /// 向系统中添加一个进程的pcb 171 /// 172 /// ## 参数 173 /// 174 /// - `pcb` : 进程的pcb 175 /// 176 /// ## 返回值 177 /// 178 /// 无 179 pub fn add_pcb(pcb: Arc<ProcessControlBlock>) { 180 ALL_PROCESS 181 .lock_irqsave() 182 .as_mut() 183 .unwrap() 184 .insert(pcb.pid(), pcb.clone()); 185 } 186 187 /// 唤醒一个进程 188 pub fn wakeup(pcb: &Arc<ProcessControlBlock>) -> Result<(), SystemError> { 189 let _guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 190 let state = pcb.sched_info().inner_lock_read_irqsave().state(); 191 if state.is_blocked() { 192 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 193 let state = writer.state(); 194 if state.is_blocked() { 195 writer.set_state(ProcessState::Runnable); 196 // avoid deadlock 197 drop(writer); 198 199 sched_enqueue(pcb.clone(), true); 200 return Ok(()); 201 } else if state.is_exited() { 202 return Err(SystemError::EINVAL); 203 } else { 204 return Ok(()); 205 } 206 } else if state.is_exited() { 207 return Err(SystemError::EINVAL); 208 } else { 209 return Ok(()); 210 } 211 } 212 213 /// 唤醒暂停的进程 214 pub fn wakeup_stop(pcb: &Arc<ProcessControlBlock>) -> Result<(), SystemError> { 215 let _guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 216 let state = pcb.sched_info().inner_lock_read_irqsave().state(); 217 if let ProcessState::Stopped = state { 218 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 219 let state = writer.state(); 220 if let ProcessState::Stopped = state { 221 writer.set_state(ProcessState::Runnable); 222 // avoid deadlock 223 drop(writer); 224 225 sched_enqueue(pcb.clone(), true); 226 return Ok(()); 227 } else if state.is_runnable() { 228 return Ok(()); 229 } else { 230 return Err(SystemError::EINVAL); 231 } 232 } else if state.is_runnable() { 233 return Ok(()); 234 } else { 235 return Err(SystemError::EINVAL); 236 } 237 } 238 239 /// 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 240 /// 241 /// ## 注意 242 /// 243 /// - 进入当前函数之前，不能持有sched_info的锁 244 /// - 进入当前函数之前，必须关闭中断 245 /// - 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 246 pub fn mark_sleep(interruptable: bool) -> Result<(), SystemError> { 247 assert_eq!( 248 CurrentIrqArch::is_irq_enabled(), 249 false, 250 "interrupt must be disabled before enter ProcessManager::mark_sleep()" 251 ); 252 253 let pcb = ProcessManager::current_pcb(); 254 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 255 if !matches!(writer.state(), ProcessState::Exited(_)) { 256 writer.set_state(ProcessState::Blocked(interruptable)); 257 pcb.flags().insert(ProcessFlags::NEED_SCHEDULE); 258 drop(writer); 259 260 return Ok(()); 261 } 262 return Err(SystemError::EINTR); 263 } 264 265 /// 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 266 /// 267 /// ## 注意 268 /// 269 /// - 进入当前函数之前，不能持有sched_info的锁 270 /// - 进入当前函数之前，必须关闭中断 271 pub fn mark_stop() -> Result<(), SystemError> { 272 assert_eq!( 273 CurrentIrqArch::is_irq_enabled(), 274 false, 275 "interrupt must be disabled before enter ProcessManager::mark_stop()" 276 ); 277 278 let pcb = ProcessManager::current_pcb(); 279 let mut writer = pcb.sched_info().inner_lock_write_irqsave(); 280 if !matches!(writer.state(), ProcessState::Exited(_)) { 281 writer.set_state(ProcessState::Stopped); 282 pcb.flags().insert(ProcessFlags::NEED_SCHEDULE); 283 drop(writer); 284 285 return Ok(()); 286 } 287 return Err(SystemError::EINTR); 288 } 289 /// 当子进程退出后向父进程发送通知 290 fn exit_notify() { 291 let current = ProcessManager::current_pcb(); 292 // 让INIT进程收养所有子进程 293 if current.pid() != Pid(1) { 294 unsafe { 295 current 296 .adopt_childen() 297 .unwrap_or_else(|e| panic!("adopte_childen failed: error: {e:?}")) 298 }; 299 let r = current.parent_pcb.read().upgrade(); 300 if r.is_none() { 301 return; 302 } 303 let parent_pcb = r.unwrap(); 304 let r = Syscall::kill(parent_pcb.pid(), Signal::SIGCHLD as i32); 305 if r.is_err() { 306 kwarn!( 307 "failed to send kill signal to {:?}'s parent pcb {:?}", 308 current.pid(), 309 parent_pcb.pid() 310 ); 311 } 312 // todo: 这里需要向父进程发送SIGCHLD信号 313 // todo: 这里还需要根据线程组的信息，决定信号的发送 314 } 315 } 316 317 /// 退出当前进程 318 /// 319 /// ## 参数 320 /// 321 /// - `exit_code` : 进程的退出码 322 pub fn exit(exit_code: usize) -> ! { 323 // 关中断 324 unsafe { CurrentIrqArch::interrupt_disable() }; 325 let pcb = ProcessManager::current_pcb(); 326 pcb.sched_info 327 .inner_lock_write_irqsave() 328 .set_state(ProcessState::Exited(exit_code)); 329 pcb.wait_queue.wakeup(Some(ProcessState::Blocked(true))); 330 331 // 进行进程退出后的工作 332 let thread = pcb.thread.write(); 333 if let Some(addr) = thread.set_child_tid { 334 unsafe { clear_user(addr, core::mem::size_of::<i32>()).expect("clear tid failed") }; 335 } 336 337 if let Some(addr) = thread.clear_child_tid { 338 if Arc::strong_count(&pcb.basic().user_vm().expect("User VM Not found")) > 1 { 339 let _ = 340 Futex::futex_wake(addr, FutexFlag::FLAGS_MATCH_NONE, 1, FUTEX_BITSET_MATCH_ANY); 341 } 342 unsafe { clear_user(addr, core::mem::size_of::<i32>()).expect("clear tid failed") }; 343 } 344 345 // 如果是vfork出来的进程，则需要处理completion 346 if thread.vfork_done.is_some() { 347 thread.vfork_done.as_ref().unwrap().complete_all(); 348 } 349 drop(thread); 350 unsafe { pcb.basic_mut().set_user_vm(None) }; 351 drop(pcb); 352 ProcessManager::exit_notify(); 353 unsafe { CurrentIrqArch::interrupt_enable() }; 354 355 sched(); 356 loop {} 357 } 358 359 pub unsafe fn release(pid: Pid) { 360 let pcb = ProcessManager::find(pid); 361 if !pcb.is_none() { 362 // let pcb = pcb.unwrap(); 363 // 判断该pcb是否在全局没有任何引用 364 // 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。 365 // 因此目前暂时注释掉，使得能跑 366 // if Arc::strong_count(&pcb) <= 2 { 367 // drop(pcb); 368 // ALL_PROCESS.lock().as_mut().unwrap().remove(&pid); 369 // } else { 370 // // 如果不为1就panic 371 // let msg = format!("pcb '{:?}' is still referenced, strong count={}",pcb.pid(), Arc::strong_count(&pcb)); 372 // kerror!("{}", msg); 373 // panic!() 374 // } 375 376 ALL_PROCESS.lock_irqsave().as_mut().unwrap().remove(&pid); 377 } 378 } 379 380 /// 上下文切换完成后的钩子函数 381 unsafe fn switch_finish_hook() { 382 // kdebug!("switch_finish_hook"); 383 let prev_pcb = SWITCH_RESULT 384 .as_mut() 385 .unwrap() 386 .get_mut() 387 .prev_pcb 388 .take() 389 .expect("prev_pcb is None"); 390 let next_pcb = SWITCH_RESULT 391 .as_mut() 392 .unwrap() 393 .get_mut() 394 .next_pcb 395 .take() 396 .expect("next_pcb is None"); 397 398 // 由于进程切换前使用了SpinLockGuard::leak()，所以这里需要手动释放锁 399 prev_pcb.arch_info.force_unlock(); 400 next_pcb.arch_info.force_unlock(); 401 } 402 403 /// 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 404 /// 405 /// ## 参数 406 /// 407 /// - `pcb` : 进程的pcb 408 #[allow(dead_code)] 409 pub fn kick(pcb: &Arc<ProcessControlBlock>) { 410 ProcessManager::current_pcb().preempt_disable(); 411 let cpu_id = pcb.sched_info().on_cpu(); 412 413 if let Some(cpu_id) = cpu_id { 414 let cpu_id = cpu_id; 415 416 if pcb.pid() == CPU_EXECUTING.get(cpu_id) { 417 kick_cpu(cpu_id).expect("ProcessManager::kick(): Failed to kick cpu"); 418 } 419 } 420 421 ProcessManager::current_pcb().preempt_enable(); 422 } 423 } 424 425 /// 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 426 #[cfg(target_arch = "x86_64")] 427 pub unsafe extern "sysv64" fn switch_finish_hook() { 428 ProcessManager::switch_finish_hook(); 429 } 430 #[cfg(target_arch = "riscv64")] 431 pub unsafe extern "C" fn switch_finish_hook() { 432 ProcessManager::switch_finish_hook(); 433 } 434 435 int_like!(Pid, AtomicPid, usize, AtomicUsize); 436 437 impl Hash for Pid { 438 fn hash<H: Hasher>(&self, state: &mut H) { 439 self.0.hash(state); 440 } 441 } 442 443 impl Pid { 444 pub fn to_string(&self) -> String { 445 self.0.to_string() 446 } 447 } 448 449 #[derive(Debug, Clone, Copy, PartialEq, Eq)] 450 pub enum ProcessState { 451 /// The process is running on a CPU or in a run queue. 452 Runnable, 453 /// The process is waiting for an event to occur. 454 /// 其中的bool表示该等待过程是否可以被打断。 455 /// - 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。 456 /// - 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。 457 Blocked(bool), 458 /// 进程被信号终止 459 Stopped, 460 /// 进程已经退出，usize表示进程的退出码 461 Exited(usize), 462 } 463 464 #[allow(dead_code)] 465 impl ProcessState { 466 #[inline(always)] 467 pub fn is_runnable(&self) -> bool { 468 return matches!(self, ProcessState::Runnable); 469 } 470 471 #[inline(always)] 472 pub fn is_blocked(&self) -> bool { 473 return matches!(self, ProcessState::Blocked(_)); 474 } 475 476 #[inline(always)] 477 pub fn is_blocked_interruptable(&self) -> bool { 478 return matches!(self, ProcessState::Blocked(true)); 479 } 480 481 /// Returns `true` if the process state is [`Exited`]. 482 #[inline(always)] 483 pub fn is_exited(&self) -> bool { 484 return matches!(self, ProcessState::Exited(_)); 485 } 486 487 /// Returns `true` if the process state is [`Stopped`]. 488 /// 489 /// [`Stopped`]: ProcessState::Stopped 490 #[inline(always)] 491 pub fn is_stopped(&self) -> bool { 492 matches!(self, ProcessState::Stopped) 493 } 494 495 /// Returns exit code if the process state is [`Exited`]. 496 #[inline(always)] 497 pub fn exit_code(&self) -> Option<usize> { 498 match self { 499 ProcessState::Exited(code) => Some(*code), 500 _ => None, 501 } 502 } 503 } 504 505 bitflags! { 506 /// pcb的标志位 507 pub struct ProcessFlags: usize { 508 /// 当前pcb表示一个内核线程 509 const KTHREAD = 1 << 0; 510 /// 当前进程需要被调度 511 const NEED_SCHEDULE = 1 << 1; 512 /// 进程由于vfork而与父进程存在资源共享 513 const VFORK = 1 << 2; 514 /// 进程不可被冻结 515 const NOFREEZE = 1 << 3; 516 /// 进程正在退出 517 const EXITING = 1 << 4; 518 /// 进程由于接收到终止信号唤醒 519 const WAKEKILL = 1 << 5; 520 /// 进程由于接收到信号而退出.(Killed by a signal) 521 const SIGNALED = 1 << 6; 522 /// 进程需要迁移到其他cpu上 523 const NEED_MIGRATE = 1 << 7; 524 } 525 } 526 527 #[derive(Debug)] 528 pub struct ProcessControlBlock { 529 /// 当前进程的pid 530 pid: Pid, 531 /// 当前进程的线程组id（这个值在同一个线程组内永远不变） 532 tgid: Pid, 533 534 basic: RwLock<ProcessBasicInfo>, 535 /// 当前进程的自旋锁持有计数 536 preempt_count: AtomicUsize, 537 538 flags: LockFreeFlags<ProcessFlags>, 539 worker_private: SpinLock<Option<WorkerPrivate>>, 540 /// 进程的内核栈 541 kernel_stack: RwLock<KernelStack>, 542 543 /// 系统调用栈 544 syscall_stack: RwLock<KernelStack>, 545 546 /// 与调度相关的信息 547 sched_info: ProcessSchedulerInfo, 548 /// 与处理器架构相关的信息 549 arch_info: SpinLock<ArchPCBInfo>, 550 /// 与信号处理相关的信息(似乎可以是无锁的) 551 sig_info: RwLock<ProcessSignalInfo>, 552 /// 信号处理结构体 553 sig_struct: SpinLock<SignalStruct>, 554 /// 退出信号S 555 exit_signal: AtomicSignal, 556 557 /// 父进程指针 558 parent_pcb: RwLock<Weak<ProcessControlBlock>>, 559 /// 真实父进程指针 560 real_parent_pcb: RwLock<Weak<ProcessControlBlock>>, 561 562 /// 子进程链表 563 children: RwLock<Vec<Pid>>, 564 565 /// 等待队列 566 wait_queue: WaitQueue, 567 568 /// 线程信息 569 thread: RwLock<ThreadInfo>, 570 } 571 572 impl ProcessControlBlock { 573 /// Generate a new pcb. 574 /// 575 /// ## 参数 576 /// 577 /// - `name` : 进程的名字 578 /// - `kstack` : 进程的内核栈 579 /// 580 /// ## 返回值 581 /// 582 /// 返回一个新的pcb 583 pub fn new(name: String, kstack: KernelStack) -> Arc<Self> { 584 return Self::do_create_pcb(name, kstack, false); 585 } 586 587 /// 创建一个新的idle进程 588 /// 589 /// 请注意，这个函数只能在进程管理初始化的时候调用。 590 pub fn new_idle(cpu_id: u32, kstack: KernelStack) -> Arc<Self> { 591 let name = format!("idle-{}", cpu_id); 592 return Self::do_create_pcb(name, kstack, true); 593 } 594 595 #[inline(never)] 596 fn do_create_pcb(name: String, kstack: KernelStack, is_idle: bool) -> Arc<Self> { 597 let (pid, ppid, cwd) = if is_idle { 598 (Pid(0), Pid(0), "/".to_string()) 599 } else { 600 let ppid = ProcessManager::current_pcb().pid(); 601 let cwd = ProcessManager::current_pcb().basic().cwd(); 602 (Self::generate_pid(), ppid, cwd) 603 }; 604 605 let basic_info = ProcessBasicInfo::new(Pid(0), ppid, name, cwd, None); 606 let preempt_count = AtomicUsize::new(0); 607 let flags = unsafe { LockFreeFlags::new(ProcessFlags::empty()) }; 608 609 let sched_info = ProcessSchedulerInfo::new(None); 610 let arch_info = SpinLock::new(ArchPCBInfo::new(&kstack)); 611 612 let ppcb: Weak<ProcessControlBlock> = ProcessManager::find(ppid) 613 .map(|p| Arc::downgrade(&p)) 614 .unwrap_or_else(|| Weak::new()); 615 616 let pcb = Self { 617 pid, 618 tgid: pid, 619 basic: basic_info, 620 preempt_count, 621 flags, 622 kernel_stack: RwLock::new(kstack), 623 syscall_stack: RwLock::new(KernelStack::new().unwrap()), 624 worker_private: SpinLock::new(None), 625 sched_info, 626 arch_info, 627 sig_info: RwLock::new(ProcessSignalInfo::default()), 628 sig_struct: SpinLock::new(SignalStruct::new()), 629 exit_signal: AtomicSignal::new(Signal::SIGCHLD), 630 parent_pcb: RwLock::new(ppcb.clone()), 631 real_parent_pcb: RwLock::new(ppcb), 632 children: RwLock::new(Vec::new()), 633 wait_queue: WaitQueue::INIT, 634 thread: RwLock::new(ThreadInfo::new()), 635 }; 636 637 // 初始化系统调用栈 638 #[cfg(target_arch = "x86_64")] 639 pcb.arch_info 640 .lock() 641 .init_syscall_stack(&pcb.syscall_stack.read()); 642 643 let pcb = Arc::new(pcb); 644 645 // 设置进程的arc指针到内核栈和系统调用栈的最低地址处 646 unsafe { 647 pcb.kernel_stack 648 .write() 649 .set_pcb(Arc::downgrade(&pcb)) 650 .unwrap(); 651 652 pcb.syscall_stack 653 .write() 654 .set_pcb(Arc::downgrade(&pcb)) 655 .unwrap() 656 }; 657 658 // 将当前pcb加入父进程的子进程哈希表中 659 if pcb.pid() > Pid(1) { 660 if let Some(ppcb_arc) = pcb.parent_pcb.read().upgrade() { 661 let mut children = ppcb_arc.children.write_irqsave(); 662 children.push(pcb.pid()); 663 } else { 664 panic!("parent pcb is None"); 665 } 666 } 667 668 return pcb; 669 } 670 671 /// 生成一个新的pid 672 #[inline(always)] 673 fn generate_pid() -> Pid { 674 static NEXT_PID: AtomicPid = AtomicPid::new(Pid(1)); 675 return NEXT_PID.fetch_add(Pid(1), Ordering::SeqCst); 676 } 677 678 /// 返回当前进程的锁持有计数 679 #[inline(always)] 680 pub fn preempt_count(&self) -> usize { 681 return self.preempt_count.load(Ordering::SeqCst); 682 } 683 684 /// 增加当前进程的锁持有计数 685 #[inline(always)] 686 pub fn preempt_disable(&self) { 687 self.preempt_count.fetch_add(1, Ordering::SeqCst); 688 } 689 690 /// 减少当前进程的锁持有计数 691 #[inline(always)] 692 pub fn preempt_enable(&self) { 693 self.preempt_count.fetch_sub(1, Ordering::SeqCst); 694 } 695 696 #[inline(always)] 697 pub unsafe fn set_preempt_count(&self, count: usize) { 698 self.preempt_count.store(count, Ordering::SeqCst); 699 } 700 701 #[inline(always)] 702 pub fn flags(&self) -> &mut ProcessFlags { 703 return self.flags.get_mut(); 704 } 705 706 /// 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 707 /// 否则会导致死锁 708 #[inline(always)] 709 pub fn basic(&self) -> RwLockReadGuard<ProcessBasicInfo> { 710 return self.basic.read(); 711 } 712 713 #[inline(always)] 714 pub fn set_name(&self, name: String) { 715 self.basic.write().set_name(name); 716 } 717 718 #[inline(always)] 719 pub fn basic_mut(&self) -> RwLockWriteGuard<ProcessBasicInfo> { 720 return self.basic.write_irqsave(); 721 } 722 723 /// # 获取arch info的锁，同时关闭中断 724 #[inline(always)] 725 pub fn arch_info_irqsave(&self) -> SpinLockGuard<ArchPCBInfo> { 726 return self.arch_info.lock_irqsave(); 727 } 728 729 /// # 获取arch info的锁，但是不关闭中断 730 /// 731 /// 由于arch info在进程切换的时候会使用到， 732 /// 因此在中断上下文外，获取arch info 而不irqsave是不安全的. 733 /// 734 /// 只能在以下情况下使用这个函数： 735 /// - 在中断上下文中（中断已经禁用），获取arch info的锁。 736 /// - 刚刚创建新的pcb 737 #[inline(always)] 738 pub unsafe fn arch_info(&self) -> SpinLockGuard<ArchPCBInfo> { 739 return self.arch_info.lock(); 740 } 741 742 #[inline(always)] 743 pub fn kernel_stack(&self) -> RwLockReadGuard<KernelStack> { 744 return self.kernel_stack.read(); 745 } 746 747 #[inline(always)] 748 #[allow(dead_code)] 749 pub fn kernel_stack_mut(&self) -> RwLockWriteGuard<KernelStack> { 750 return self.kernel_stack.write(); 751 } 752 753 #[inline(always)] 754 pub fn sched_info(&self) -> &ProcessSchedulerInfo { 755 return &self.sched_info; 756 } 757 758 #[inline(always)] 759 pub fn worker_private(&self) -> SpinLockGuard<Option<WorkerPrivate>> { 760 return self.worker_private.lock(); 761 } 762 763 #[inline(always)] 764 pub fn pid(&self) -> Pid { 765 return self.pid; 766 } 767 768 #[inline(always)] 769 pub fn tgid(&self) -> Pid { 770 return self.tgid; 771 } 772 773 /// 获取文件描述符表的Arc指针 774 #[inline(always)] 775 pub fn fd_table(&self) -> Arc<RwLock<FileDescriptorVec>> { 776 return self.basic.read().fd_table().unwrap(); 777 } 778 779 /// 根据文件描述符序号，获取socket对象的Arc指针 780 /// 781 /// ## 参数 782 /// 783 /// - `fd` 文件描述符序号 784 /// 785 /// ## 返回值 786 /// 787 /// 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 788 pub fn get_socket(&self, fd: i32) -> Option<Arc<SocketInode>> { 789 let binding = ProcessManager::current_pcb().fd_table(); 790 let fd_table_guard = binding.read(); 791 792 let f = fd_table_guard.get_file_by_fd(fd)?; 793 drop(fd_table_guard); 794 795 let guard = f.lock(); 796 if guard.file_type() != FileType::Socket { 797 return None; 798 } 799 let socket: Arc<SocketInode> = guard 800 .inode() 801 .downcast_arc::<SocketInode>() 802 .expect("Not a socket inode"); 803 return Some(socket); 804 } 805 806 /// 当前进程退出时,让初始进程收养所有子进程 807 unsafe fn adopt_childen(&self) -> Result<(), SystemError> { 808 match ProcessManager::find(Pid(1)) { 809 Some(init_pcb) => { 810 let childen_guard = self.children.write(); 811 let mut init_childen_guard = init_pcb.children.write(); 812 813 childen_guard.iter().for_each(|pid| { 814 init_childen_guard.push(*pid); 815 }); 816 817 return Ok(()); 818 } 819 _ => Err(SystemError::ECHILD), 820 } 821 } 822 823 /// 生成进程的名字 824 pub fn generate_name(program_path: &str, args: &Vec<String>) -> String { 825 let mut name = program_path.to_string(); 826 for arg in args { 827 name.push_str(arg); 828 name.push(' '); 829 } 830 return name; 831 } 832 833 pub fn sig_info(&self) -> RwLockReadGuard<ProcessSignalInfo> { 834 self.sig_info.read() 835 } 836 837 pub fn sig_info_irqsave(&self) -> RwLockReadGuard<ProcessSignalInfo> { 838 self.sig_info.read_irqsave() 839 } 840 841 pub fn try_siginfo(&self, times: u8) -> Option<RwLockReadGuard<ProcessSignalInfo>> { 842 for _ in 0..times { 843 if let Some(r) = self.sig_info.try_read() { 844 return Some(r); 845 } 846 } 847 848 return None; 849 } 850 851 pub fn sig_info_mut(&self) -> RwLockWriteGuard<ProcessSignalInfo> { 852 self.sig_info.write_irqsave() 853 } 854 855 pub fn try_siginfo_mut(&self, times: u8) -> Option<RwLockWriteGuard<ProcessSignalInfo>> { 856 for _ in 0..times { 857 if let Some(r) = self.sig_info.try_write() { 858 return Some(r); 859 } 860 } 861 862 return None; 863 } 864 865 pub fn sig_struct(&self) -> SpinLockGuard<SignalStruct> { 866 self.sig_struct.lock() 867 } 868 869 pub fn try_sig_struct_irq(&self, times: u8) -> Option<SpinLockGuard<SignalStruct>> { 870 for _ in 0..times { 871 if let Ok(r) = self.sig_struct.try_lock_irqsave() { 872 return Some(r); 873 } 874 } 875 876 return None; 877 } 878 879 pub fn sig_struct_irqsave(&self) -> SpinLockGuard<SignalStruct> { 880 self.sig_struct.lock_irqsave() 881 } 882 } 883 884 impl Drop for ProcessControlBlock { 885 fn drop(&mut self) { 886 // 在ProcFS中,解除进程的注册 887 procfs_unregister_pid(self.pid()) 888 .unwrap_or_else(|e| panic!("procfs_unregister_pid failed: error: {e:?}")); 889 890 if let Some(ppcb) = self.parent_pcb.read().upgrade() { 891 ppcb.children.write().retain(|pid| *pid != self.pid()); 892 } 893 } 894 } 895 896 /// 线程信息 897 #[derive(Debug)] 898 pub struct ThreadInfo { 899 // 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 900 clear_child_tid: Option<VirtAddr>, 901 set_child_tid: Option<VirtAddr>, 902 903 vfork_done: Option<Arc<Completion>>, 904 /// 线程组的组长 905 group_leader: Weak<ProcessControlBlock>, 906 } 907 908 impl ThreadInfo { 909 pub fn new() -> Self { 910 Self { 911 clear_child_tid: None, 912 set_child_tid: None, 913 vfork_done: None, 914 group_leader: Weak::default(), 915 } 916 } 917 918 pub fn group_leader(&self) -> Option<Arc<ProcessControlBlock>> { 919 return self.group_leader.upgrade(); 920 } 921 } 922 923 /// 进程的基本信息 924 /// 925 /// 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。 926 #[derive(Debug)] 927 pub struct ProcessBasicInfo { 928 /// 当前进程的进程组id 929 pgid: Pid, 930 /// 当前进程的父进程的pid 931 ppid: Pid, 932 /// 进程的名字 933 name: String, 934 935 /// 当前进程的工作目录 936 cwd: String, 937 938 /// 用户地址空间 939 user_vm: Option<Arc<AddressSpace>>, 940 941 /// 文件描述符表 942 fd_table: Option<Arc<RwLock<FileDescriptorVec>>>, 943 } 944 945 impl ProcessBasicInfo { 946 #[inline(never)] 947 pub fn new( 948 pgid: Pid, 949 ppid: Pid, 950 name: String, 951 cwd: String, 952 user_vm: Option<Arc<AddressSpace>>, 953 ) -> RwLock<Self> { 954 let fd_table = Arc::new(RwLock::new(FileDescriptorVec::new())); 955 return RwLock::new(Self { 956 pgid, 957 ppid, 958 name, 959 cwd, 960 user_vm, 961 fd_table: Some(fd_table), 962 }); 963 } 964 965 pub fn pgid(&self) -> Pid { 966 return self.pgid; 967 } 968 969 pub fn ppid(&self) -> Pid { 970 return self.ppid; 971 } 972 973 pub fn name(&self) -> &str { 974 return &self.name; 975 } 976 977 pub fn set_name(&mut self, name: String) { 978 self.name = name; 979 } 980 981 pub fn cwd(&self) -> String { 982 return self.cwd.clone(); 983 } 984 pub fn set_cwd(&mut self, path: String) { 985 return self.cwd = path; 986 } 987 988 pub fn user_vm(&self) -> Option<Arc<AddressSpace>> { 989 return self.user_vm.clone(); 990 } 991 992 pub unsafe fn set_user_vm(&mut self, user_vm: Option<Arc<AddressSpace>>) { 993 self.user_vm = user_vm; 994 } 995 996 pub fn fd_table(&self) -> Option<Arc<RwLock<FileDescriptorVec>>> { 997 return self.fd_table.clone(); 998 } 999 1000 pub fn set_fd_table(&mut self, fd_table: Option<Arc<RwLock<FileDescriptorVec>>>) { 1001 self.fd_table = fd_table; 1002 } 1003 } 1004 1005 #[derive(Debug)] 1006 pub struct ProcessSchedulerInfo { 1007 /// 当前进程所在的cpu 1008 on_cpu: AtomicI32, 1009 /// 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）， 1010 /// 该字段存储要被迁移到的目标处理器核心号 1011 migrate_to: AtomicI32, 1012 inner_locked: RwLock<InnerSchedInfo>, 1013 /// 进程的调度优先级 1014 priority: SchedPriority, 1015 /// 当前进程的虚拟运行时间 1016 virtual_runtime: AtomicIsize, 1017 /// 由实时调度器管理的时间片 1018 rt_time_slice: AtomicIsize, 1019 } 1020 1021 #[derive(Debug)] 1022 pub struct InnerSchedInfo { 1023 /// 当前进程的状态 1024 state: ProcessState, 1025 /// 进程的调度策略 1026 sched_policy: SchedPolicy, 1027 } 1028 1029 impl InnerSchedInfo { 1030 pub fn state(&self) -> ProcessState { 1031 return self.state; 1032 } 1033 1034 pub fn set_state(&mut self, state: ProcessState) { 1035 self.state = state; 1036 } 1037 1038 pub fn policy(&self) -> SchedPolicy { 1039 return self.sched_policy; 1040 } 1041 } 1042 1043 impl ProcessSchedulerInfo { 1044 #[inline(never)] 1045 pub fn new(on_cpu: Option<u32>) -> Self { 1046 let cpu_id = match on_cpu { 1047 Some(cpu_id) => cpu_id as i32, 1048 None => -1, 1049 }; 1050 return Self { 1051 on_cpu: AtomicI32::new(cpu_id), 1052 migrate_to: AtomicI32::new(-1), 1053 inner_locked: RwLock::new(InnerSchedInfo { 1054 state: ProcessState::Blocked(false), 1055 sched_policy: SchedPolicy::CFS, 1056 }), 1057 virtual_runtime: AtomicIsize::new(0), 1058 rt_time_slice: AtomicIsize::new(0), 1059 priority: SchedPriority::new(100).unwrap(), 1060 }; 1061 } 1062 1063 pub fn on_cpu(&self) -> Option<u32> { 1064 let on_cpu = self.on_cpu.load(Ordering::SeqCst); 1065 if on_cpu == -1 { 1066 return None; 1067 } else { 1068 return Some(on_cpu as u32); 1069 } 1070 } 1071 1072 pub fn set_on_cpu(&self, on_cpu: Option<u32>) { 1073 if let Some(cpu_id) = on_cpu { 1074 self.on_cpu.store(cpu_id as i32, Ordering::SeqCst); 1075 } else { 1076 self.on_cpu.store(-1, Ordering::SeqCst); 1077 } 1078 } 1079 1080 pub fn migrate_to(&self) -> Option<u32> { 1081 let migrate_to = self.migrate_to.load(Ordering::SeqCst); 1082 if migrate_to == -1 { 1083 return None; 1084 } else { 1085 return Some(migrate_to as u32); 1086 } 1087 } 1088 1089 pub fn set_migrate_to(&self, migrate_to: Option<u32>) { 1090 if let Some(data) = migrate_to { 1091 self.migrate_to.store(data as i32, Ordering::SeqCst); 1092 } else { 1093 self.migrate_to.store(-1, Ordering::SeqCst) 1094 } 1095 } 1096 1097 pub fn inner_lock_write_irqsave(&self) -> RwLockWriteGuard<InnerSchedInfo> { 1098 return self.inner_locked.write_irqsave(); 1099 } 1100 1101 pub fn inner_lock_read_irqsave(&self) -> RwLockReadGuard<InnerSchedInfo> { 1102 return self.inner_locked.read_irqsave(); 1103 } 1104 1105 pub fn inner_lock_try_read_irqsave( 1106 &self, 1107 times: u8, 1108 ) -> Option<RwLockReadGuard<InnerSchedInfo>> { 1109 for _ in 0..times { 1110 if let Some(r) = self.inner_locked.try_read_irqsave() { 1111 return Some(r); 1112 } 1113 } 1114 1115 return None; 1116 } 1117 1118 pub fn inner_lock_try_upgradable_read_irqsave( 1119 &self, 1120 times: u8, 1121 ) -> Option<RwLockUpgradableGuard<InnerSchedInfo>> { 1122 for _ in 0..times { 1123 if let Some(r) = self.inner_locked.try_upgradeable_read_irqsave() { 1124 return Some(r); 1125 } 1126 } 1127 1128 return None; 1129 } 1130 1131 pub fn virtual_runtime(&self) -> isize { 1132 return self.virtual_runtime.load(Ordering::SeqCst); 1133 } 1134 1135 pub fn set_virtual_runtime(&self, virtual_runtime: isize) { 1136 self.virtual_runtime 1137 .store(virtual_runtime, Ordering::SeqCst); 1138 } 1139 pub fn increase_virtual_runtime(&self, delta: isize) { 1140 self.virtual_runtime.fetch_add(delta, Ordering::SeqCst); 1141 } 1142 1143 pub fn rt_time_slice(&self) -> isize { 1144 return self.rt_time_slice.load(Ordering::SeqCst); 1145 } 1146 1147 pub fn set_rt_time_slice(&self, rt_time_slice: isize) { 1148 self.rt_time_slice.store(rt_time_slice, Ordering::SeqCst); 1149 } 1150 1151 pub fn increase_rt_time_slice(&self, delta: isize) { 1152 self.rt_time_slice.fetch_add(delta, Ordering::SeqCst); 1153 } 1154 1155 pub fn priority(&self) -> SchedPriority { 1156 return self.priority; 1157 } 1158 } 1159 1160 #[derive(Debug, Clone)] 1161 pub struct KernelStack { 1162 stack: Option<AlignedBox<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>>, 1163 /// 标记该内核栈是否可以被释放 1164 can_be_freed: bool, 1165 } 1166 1167 impl KernelStack { 1168 pub const SIZE: usize = 0x4000; 1169 pub const ALIGN: usize = 0x4000; 1170 1171 pub fn new() -> Result<Self, SystemError> { 1172 return Ok(Self { 1173 stack: Some( 1174 AlignedBox::<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>::new_zeroed()?, 1175 ), 1176 can_be_freed: true, 1177 }); 1178 } 1179 1180 /// 根据已有的空间，构造一个内核栈结构体 1181 /// 1182 /// 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！ 1183 pub unsafe fn from_existed(base: VirtAddr) -> Result<Self, SystemError> { 1184 if base.is_null() || base.check_aligned(Self::ALIGN) == false { 1185 return Err(SystemError::EFAULT); 1186 } 1187 1188 return Ok(Self { 1189 stack: Some( 1190 AlignedBox::<[u8; KernelStack::SIZE], { KernelStack::ALIGN }>::new_unchecked( 1191 base.data() as *mut [u8; KernelStack::SIZE], 1192 ), 1193 ), 1194 can_be_freed: false, 1195 }); 1196 } 1197 1198 /// 返回内核栈的起始虚拟地址(低地址) 1199 pub fn start_address(&self) -> VirtAddr { 1200 return VirtAddr::new(self.stack.as_ref().unwrap().as_ptr() as usize); 1201 } 1202 1203 /// 返回内核栈的结束虚拟地址(高地址)(不包含该地址) 1204 pub fn stack_max_address(&self) -> VirtAddr { 1205 return VirtAddr::new(self.stack.as_ref().unwrap().as_ptr() as usize + Self::SIZE); 1206 } 1207 1208 pub unsafe fn set_pcb(&mut self, pcb: Weak<ProcessControlBlock>) -> Result<(), SystemError> { 1209 // 将一个Weak<ProcessControlBlock>放到内核栈的最低地址处 1210 let p: *const ProcessControlBlock = Weak::into_raw(pcb); 1211 let stack_bottom_ptr = self.start_address().data() as *mut *const ProcessControlBlock; 1212 1213 // 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 1214 if unlikely(unsafe { !(*stack_bottom_ptr).is_null() }) { 1215 kerror!("kernel stack bottom is not null: {:p}", *stack_bottom_ptr); 1216 return Err(SystemError::EPERM); 1217 } 1218 // 将pcb的地址放到内核栈的最低地址处 1219 unsafe { 1220 *stack_bottom_ptr = p; 1221 } 1222 1223 return Ok(()); 1224 } 1225 1226 /// 清除内核栈的pcb指针 1227 /// 1228 /// ## 参数 1229 /// 1230 /// - `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 1231 pub unsafe fn clear_pcb(&mut self, force: bool) { 1232 let stack_bottom_ptr = self.start_address().data() as *mut *const ProcessControlBlock; 1233 if unlikely(unsafe { (*stack_bottom_ptr).is_null() }) { 1234 return; 1235 } 1236 1237 if !force { 1238 let pcb_ptr: Weak<ProcessControlBlock> = Weak::from_raw(*stack_bottom_ptr); 1239 drop(pcb_ptr); 1240 } 1241 1242 *stack_bottom_ptr = core::ptr::null(); 1243 } 1244 1245 /// 返回指向当前内核栈pcb的Arc指针 1246 #[allow(dead_code)] 1247 pub unsafe fn pcb(&self) -> Option<Arc<ProcessControlBlock>> { 1248 // 从内核栈的最低地址处取出pcb的地址 1249 let p = self.stack.as_ref().unwrap().as_ptr() as *const *const ProcessControlBlock; 1250 if unlikely(unsafe { (*p).is_null() }) { 1251 return None; 1252 } 1253 1254 // 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 1255 let weak_wrapper: ManuallyDrop<Weak<ProcessControlBlock>> = 1256 ManuallyDrop::new(Weak::from_raw(*p)); 1257 1258 let new_arc: Arc<ProcessControlBlock> = weak_wrapper.upgrade()?; 1259 return Some(new_arc); 1260 } 1261 } 1262 1263 impl Drop for KernelStack { 1264 fn drop(&mut self) { 1265 if !self.stack.is_none() { 1266 let ptr = self.stack.as_ref().unwrap().as_ptr() as *const *const ProcessControlBlock; 1267 if unsafe { !(*ptr).is_null() } { 1268 let pcb_ptr: Weak<ProcessControlBlock> = unsafe { Weak::from_raw(*ptr) }; 1269 drop(pcb_ptr); 1270 } 1271 } 1272 // 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 1273 if !self.can_be_freed { 1274 let bx = self.stack.take(); 1275 core::mem::forget(bx); 1276 } 1277 } 1278 } 1279 1280 pub fn process_init() { 1281 ProcessManager::init(); 1282 } 1283 1284 #[derive(Debug)] 1285 pub struct ProcessSignalInfo { 1286 // 当前进程 1287 sig_block: SigSet, 1288 // sig_pending 中存储当前线程要处理的信号 1289 sig_pending: SigPending, 1290 // sig_shared_pending 中存储当前线程所属进程要处理的信号 1291 sig_shared_pending: SigPending, 1292 } 1293 1294 impl ProcessSignalInfo { 1295 pub fn sig_block(&self) -> &SigSet { 1296 &self.sig_block 1297 } 1298 1299 pub fn sig_pending(&self) -> &SigPending { 1300 &self.sig_pending 1301 } 1302 1303 pub fn sig_pending_mut(&mut self) -> &mut SigPending { 1304 &mut self.sig_pending 1305 } 1306 1307 pub fn sig_block_mut(&mut self) -> &mut SigSet { 1308 &mut self.sig_block 1309 } 1310 1311 pub fn sig_shared_pending_mut(&mut self) -> &mut SigPending { 1312 &mut self.sig_shared_pending 1313 } 1314 1315 pub fn sig_shared_pending(&self) -> &SigPending { 1316 &self.sig_shared_pending 1317 } 1318 1319 /// 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 1320 /// 1321 /// ## 参数 1322 /// 1323 /// - `sig_mask` 被忽略掉的信号 1324 /// 1325 pub fn dequeue_signal(&mut self, sig_mask: &SigSet) -> (Signal, Option<SigInfo>) { 1326 let res = self.sig_pending.dequeue_signal(sig_mask); 1327 if res.0 != Signal::INVALID { 1328 return res; 1329 } else { 1330 return self.sig_shared_pending.dequeue_signal(sig_mask); 1331 } 1332 } 1333 } 1334 1335 impl Default for ProcessSignalInfo { 1336 fn default() -> Self { 1337 Self { 1338 sig_block: SigSet::empty(), 1339 sig_pending: SigPending::default(), 1340 sig_shared_pending: SigPending::default(), 1341 } 1342 } 1343 } 1344