add cargo fmt in Makefile, and exec make fmt

wait child exit in forktree

.github/workflows/build-doc.yml

@@ -1,25 +0,0 @@
-name: Build Rust Doc
-
-on: [push]
-
-env:
-  CARGO_TERM_COLOR: always
-
-jobs:
-  build-doc:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - name: Build doc
-        run: |
-          rustup target add riscv64gc-unknown-none-elf
-          rustup component add llvm-tools-preview
-          rustup component add rust-src
-          cd os
-          cargo doc --no-deps --verbose
-      - name: Deploy to Github Pages
-        uses: peaceiris/actions-gh-pages@v3
-        with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-          publish_dir: ./os/target/riscv64gc-unknown-none-elf/doc
-          destination_dir: ${{ github.ref_name }}

.github/workflows/doc-and-test.yml

@@ -0,0 +1,66 @@
+name: Build Rust Doc And Run tests
+
+on: [push]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build-doc:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly-2022-04-11
+          components: rust-src, llvm-tools-preview
+          target: riscv64gc-unknown-none-elf
+      - name: Build doc
+        run: cd os && cargo doc --no-deps --verbose
+      - name: Deploy to Github Pages
+        uses: peaceiris/actions-gh-pages@v3
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./os/target/riscv64gc-unknown-none-elf/doc
+          destination_dir: ${{ github.ref_name }}
+
+  run-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly-2022-04-11
+          components: rust-src, llvm-tools-preview
+          target: riscv64gc-unknown-none-elf
+      - uses: actions-rs/install@v0.1
+        with:
+          crate: cargo-binutils
+          version: latest
+          use-tool-cache: true
+      - name: Cache QEMU
+        uses: actions/cache@v3
+        with:
+          path: qemu-7.0.0
+          key: qemu-7.0.0-x86_64-riscv64
+      - name: Install QEMU
+        run: |
+          sudo apt-get update
+          sudo apt-get install ninja-build -y
+          if [ ! -d qemu-7.0.0 ]; then
+            wget https://download.qemu.org/qemu-7.0.0.tar.xz
+            tar -xf qemu-7.0.0.tar.xz
+            cd qemu-7.0.0
+            ./configure --target-list=riscv64-softmmu
+            make -j
+          else
+            cd qemu-7.0.0
+          fi
+          sudo make install
+          qemu-system-riscv64 --version
+
+      - name: Run usertests
+        run: cd os && make run TEST=1
+        timeout-minutes: 10

.gitignore

@@ -1,18 +1,13 @@
-.idea
-Cargo.lock
-target
+.*/*
+!.github/*
+!.vscode/settings.json
+
+**/target/
+**/Cargo.lock
+
 os/src/link_app.S
 os/src/linker.ld
 os/last-*
-os/Cargo.lock
 os/.gdb_history
-user/build
-user/target/*
-user/.idea/*
-user/Cargo.lock
-easy-fs/Cargo.lock
-easy-fs/target/*
-easy-fs-fuse/Cargo.lock
-easy-fs-fuse/target/*
 tools/
 pushall.sh

.vscode/settings.json

@@ -0,0 +1,10 @@
+{
+    // Prevent "can't find crate for `test`" error on no_std
+    // Ref: https://github.com/rust-lang/vscode-rust/issues/729
+    // For vscode-rust plugin users:
+    "rust.target": "riscv64gc-unknown-none-elf",
+    "rust.all_targets": false,
+    // For Rust Analyzer plugin users:
+    "rust-analyzer.cargo.target": "riscv64gc-unknown-none-elf",
+    "rust-analyzer.checkOnSave.allTargets": false
+}

Makefile

@@ -6,3 +6,5 @@ docker:
 
 build_docker: 
 	docker build -t ${DOCKER_NAME} .
+fmt:
+	cd easy-fs; cargo fmt; cd ../easy-fs-fuse cargo fmt; cd ../os ; cargo fmt; cd ../user; cargo fmt; cd ..

README.md

@@ -3,6 +3,8 @@ rCore-Tutorial version 3.5. See the [Documentation in Chinese](https://rcore-os.
 
 rCore-Tutorial API Docs.  See the [API Docs of Ten OSes ](#OS-API-DOCS)
 
+If you don't know  Rust Language and try to learn it, please visit [Rust Learning Resources](https://github.com/rcore-os/rCore/wiki/study-resource-of-system-programming-in-RUST)
+
 Official QQ group number: 735045051
 
 ## news
@@ -188,6 +190,44 @@ $ make run BOARD=k210
 
 Type `Ctrl+]` to disconnect from K210.
 
+## Show runtime debug info of OS kernel version
+The branch of ch9-log contains a lot of debug info. You could try to run rcore tutorial 
+for understand the internal behavior of os kernel.
+
+```sh
+$ git clone https://github.com/rcore-os/rCore-Tutorial-v3.git
+$ cd rCore-Tutorial-v3/os
+$ git checkout ch9-log
+$ make run
+......
+[rustsbi] RustSBI version 0.2.0-alpha.10, adapting to RISC-V SBI v0.3
+.______       __    __      _______.___________.  _______..______   __
+|   _  \     |  |  |  |    /       |           | /       ||   _  \ |  |
+|  |_)  |    |  |  |  |   |   (----`---|  |----`|   (----`|  |_)  ||  |
+|      /     |  |  |  |    \   \       |  |      \   \    |   _  < |  |
+|  |\  \----.|  `--'  |.----)   |      |  |  .----)   |   |  |_)  ||  |
+| _| `._____| \______/ |_______/       |__|  |_______/    |______/ |__|
+
+[rustsbi] Implementation: RustSBI-QEMU Version 0.0.2
+[rustsbi-dtb] Hart count: cluster0 with 1 cores
+[rustsbi] misa: RV64ACDFIMSU
+[rustsbi] mideleg: ssoft, stimer, sext (0x222)
+[rustsbi] medeleg: ima, ia, bkpt, la, sa, uecall, ipage, lpage, spage (0xb1ab)
+[rustsbi] pmp0: 0x10000000 ..= 0x10001fff (rw-)
+[rustsbi] pmp1: 0x2000000 ..= 0x200ffff (rw-)
+[rustsbi] pmp2: 0xc000000 ..= 0xc3fffff (rw-)
+[rustsbi] pmp3: 0x80000000 ..= 0x8fffffff (rwx)
+[rustsbi] enter supervisor 0x80200000
+[KERN] rust_main() begin
+[KERN] clear_bss() begin
+[KERN] clear_bss() end
+[KERN] mm::init() begin
+[KERN] mm::init_heap() begin
+[KERN] mm::init_heap() end
+[KERN] mm::init_frame_allocator() begin
+[KERN] mm::frame_allocator::lazy_static!FRAME_ALLOCATOR begin
+......
+```
 ## Rustdoc
 
 Currently it can only help you view the code since only a tiny part of the code has been documented.

easy-fs-fuse/.gitignore

@@ -1,3 +0,0 @@
-.idea/
-target/
-Cargo.lock

easy-fs-fuse/src/main.rs

@@ -23,6 +23,8 @@ impl BlockDevice for BlockFile {
             .expect("Error when seeking!");
         assert_eq!(file.write(buf).unwrap(), BLOCK_SZ, "Not a complete block!");
     }
+
+    fn handle_irq(&self) { unimplemented!(); }
 }
 
 fn main() {

easy-fs/src/block_dev.rs

@@ -3,4 +3,5 @@ use core::any::Any;
 pub trait BlockDevice: Send + Sync + Any {
     fn read_block(&self, block_id: usize, buf: &mut [u8]);
     fn write_block(&self, block_id: usize, buf: &[u8]);
+    fn handle_irq(&self);
 }

os/Cargo.toml

@@ -12,6 +12,7 @@ lazy_static = { version = "1.4.0", features = ["spin_no_std"] }
 buddy_system_allocator = "0.6"
 bitflags = "1.2.1"
 xmas-elf = "0.7.0"
+volatile = "0.3"
 virtio-drivers = { git = "https://github.com/rcore-os/virtio-drivers" }
 k210-pac = { git = "https://github.com/wyfcyx/k210-pac" }
 k210-hal = { git = "https://github.com/wyfcyx/k210-hal" }

os/Makefile

@@ -37,6 +37,9 @@ OBJCOPY := rust-objcopy --binary-architecture=riscv64
 # Disassembly
 DISASM ?= -x
 
+# Run usertests or usershell
+TEST ?=
+
 build: env switch-check $(KERNEL_BIN) fs-img 
 
 switch-check:
@@ -61,7 +64,7 @@ $(KERNEL_BIN): kernel
 	@$(OBJCOPY) $(KERNEL_ELF) --strip-all -O binary $@
 
 fs-img: $(APPS)
-	@cd ../user && make build
+	@cd ../user && make build TEST=$(TEST)
 	@rm -f $(FS_IMG)
 	@cd ../easy-fs-fuse && cargo run --release -- -s ../user/src/bin/ -t ../user/target/riscv64gc-unknown-none-elf/release/
 
@@ -81,7 +84,7 @@ disasm: kernel
 
 disasm-vim: kernel
 	@$(OBJDUMP) $(DISASM) $(KERNEL_ELF) > $(DISASM_TMP)
-	@vim $(DISASM_TMP)
+	@nvim $(DISASM_TMP)
 	@rm $(DISASM_TMP)
 
 run: run-inner

os/src/boards/k210.rs

@@ -21,3 +21,10 @@ pub const MMIO: &[(usize, usize)] = &[
 
 pub type BlockDeviceImpl = crate::drivers::block::SDCardWrapper;
 
+pub fn device_init() {
+    unimplemented!();
+}
+
+pub fn irq_handler() {
+    unimplemented!();
+}

os/src/boards/qemu.rs

@@ -1,6 +1,126 @@
 pub const CLOCK_FREQ: usize = 12500000;
 
-pub const MMIO: &[(usize, usize)] = &[(0x10001000, 0x1000)];
+pub const MMIO: &[(usize, usize)] = &[
+    (0x1000_0000, 0x1000),    // VIRT_UART0 in virt machine
+    (0x1000_1000, 0x1000),    // VIRT_VIRTIO in virt machine
+    (0x0C00_0000, 0x40_0000), // VIRT_PLIC in virt machine
+    (0x0010_0000, 0x00_2000), // VIRT_TEST/RTC  in virt machine
+];
 
 pub type BlockDeviceImpl = crate::drivers::block::VirtIOBlock;
+pub type CharDeviceImpl = crate::drivers::chardev::NS16550a<VIRT_UART>;
 
+pub const VIRT_PLIC: usize = 0xC00_0000;
+pub const VIRT_UART: usize = 0x1000_0000;
+
+use crate::drivers::block::BLOCK_DEVICE;
+use crate::drivers::chardev::{CharDevice, UART};
+use crate::drivers::plic::{IntrTargetPriority, PLIC};
+
+pub fn device_init() {
+    use riscv::register::sie;
+    let mut plic = unsafe { PLIC::new(VIRT_PLIC) };
+    let hart_id: usize = 0;
+    let supervisor = IntrTargetPriority::Supervisor;
+    let machine = IntrTargetPriority::Machine;
+    plic.set_threshold(hart_id, supervisor, 0);
+    plic.set_threshold(hart_id, machine, 1);
+    for intr_src_id in [1usize, 10] {
+        plic.enable(hart_id, supervisor, intr_src_id);
+        plic.set_priority(intr_src_id, 1);
+    }
+    unsafe {
+        sie::set_sext();
+    }
+}
+
+pub fn irq_handler() {
+    let mut plic = unsafe { PLIC::new(VIRT_PLIC) };
+    let intr_src_id = plic.claim(0, IntrTargetPriority::Supervisor);
+    match intr_src_id {
+        1 => BLOCK_DEVICE.handle_irq(),
+        10 => UART.handle_irq(),
+        _ => panic!("unsupported IRQ {}", intr_src_id),
+    }
+    plic.complete(0, IntrTargetPriority::Supervisor, intr_src_id);
+}
+
+//ref:: https://github.com/andre-richter/qemu-exit
+use core::arch::asm;
+
+const EXIT_SUCCESS: u32 = 0x5555; // Equals `exit(0)`. qemu successful exit
+
+const EXIT_FAILURE_FLAG: u32 = 0x3333;
+const EXIT_FAILURE: u32 = exit_code_encode(1); // Equals `exit(1)`. qemu failed exit
+const EXIT_RESET: u32 = 0x7777; // qemu reset
+
+pub trait QEMUExit {
+    /// Exit with specified return code.
+    ///
+    /// Note: For `X86`, code is binary-OR'ed with `0x1` inside QEMU.
+    fn exit(&self, code: u32) -> !;
+
+    /// Exit QEMU using `EXIT_SUCCESS`, aka `0`, if possible.
+    ///
+    /// Note: Not possible for `X86`.
+    fn exit_success(&self) -> !;
+
+    /// Exit QEMU using `EXIT_FAILURE`, aka `1`.
+    fn exit_failure(&self) -> !;
+}
+
+/// RISCV64 configuration
+pub struct RISCV64 {
+    /// Address of the sifive_test mapped device.
+    addr: u64,
+}
+
+/// Encode the exit code using EXIT_FAILURE_FLAG.
+const fn exit_code_encode(code: u32) -> u32 {
+    (code << 16) | EXIT_FAILURE_FLAG
+}
+
+impl RISCV64 {
+    /// Create an instance.
+    pub const fn new(addr: u64) -> Self {
+        RISCV64 { addr }
+    }
+}
+
+impl QEMUExit for RISCV64 {
+    /// Exit qemu with specified exit code.
+    fn exit(&self, code: u32) -> ! {
+        // If code is not a special value, we need to encode it with EXIT_FAILURE_FLAG.
+        let code_new = match code {
+            EXIT_SUCCESS | EXIT_FAILURE | EXIT_RESET => code,
+            _ => exit_code_encode(code),
+        };
+
+        unsafe {
+            asm!(
+                "sw {0}, 0({1})",
+                in(reg)code_new, in(reg)self.addr
+            );
+
+            // For the case that the QEMU exit attempt did not work, transition into an infinite
+            // loop. Calling `panic!()` here is unfeasible, since there is a good chance
+            // this function here is the last expression in the `panic!()` handler
+            // itself. This prevents a possible infinite loop.
+            loop {
+                asm!("wfi", options(nomem, nostack));
+            }
+        }
+    }
+
+    fn exit_success(&self) -> ! {
+        self.exit(EXIT_SUCCESS);
+    }
+
+    fn exit_failure(&self) -> ! {
+        self.exit(EXIT_FAILURE);
+    }
+}
+
+const VIRT_TEST: u64 = 0x100000;
+
+pub const QEMU_EXIT_HANDLE: RISCV64 = RISCV64::new(VIRT_TEST);

os/src/config.rs

@@ -8,7 +8,6 @@ pub const PAGE_SIZE: usize = 0x1000;
 pub const PAGE_SIZE_BITS: usize = 0xc;
 
 pub const TRAMPOLINE: usize = usize::MAX - PAGE_SIZE + 1;
-pub const TRAP_CONTEXT: usize = TRAMPOLINE - PAGE_SIZE;
+pub const TRAP_CONTEXT_BASE: usize = TRAMPOLINE - PAGE_SIZE;
 
 pub use crate::board::{CLOCK_FREQ, MMIO};
-

os/src/console.rs

@@ -1,4 +1,4 @@
-use crate::sbi::console_putchar;
+use crate::drivers::chardev::{CharDevice, UART};
 use core::fmt::{self, Write};
 
 struct Stdout;
@@ -6,7 +6,7 @@ struct Stdout;
 impl Write for Stdout {
     fn write_str(&mut self, s: &str) -> fmt::Result {
         for c in s.chars() {
-            console_putchar(c as usize);
+            UART.write(c as u8);
         }
         Ok(())
     }
@@ -19,13 +19,13 @@ pub fn print(args: fmt::Arguments) {
 #[macro_export]
 macro_rules! print {
     ($fmt: literal $(, $($arg: tt)+)?) => {
-        $crate::console::print(format_args!($fmt $(, $($arg)+)?));
+        $crate::console::print(format_args!($fmt $(, $($arg)+)?))
     }
 }
 
 #[macro_export]
 macro_rules! println {
     ($fmt: literal $(, $($arg: tt)+)?) => {
-        $crate::console::print(format_args!(concat!($fmt, "\n") $(, $($arg)+)?));
+        $crate::console::print(format_args!(concat!($fmt, "\n") $(, $($arg)+)?))
     }
 }

os/src/drivers/block/mod.rs

@@ -1,13 +1,13 @@
 mod sdcard;
 mod virtio_blk;
 
-pub use virtio_blk::VirtIOBlock;
 pub use sdcard::SDCardWrapper;
+pub use virtio_blk::VirtIOBlock;
 
+use crate::board::BlockDeviceImpl;
 use alloc::sync::Arc;
 use easy_fs::BlockDevice;
 use lazy_static::*;
-use crate::board::BlockDeviceImpl;
 
 lazy_static! {
     pub static ref BLOCK_DEVICE: Arc<dyn BlockDevice> = Arc::new(BlockDeviceImpl::new());

os/src/drivers/block/sdcard.rs

@@ -3,7 +3,7 @@
 #![allow(unused)]
 
 use super::BlockDevice;
-use crate::sync::UPSafeCell;
+use crate::sync::UPIntrFreeCell;
 use core::convert::TryInto;
 use k210_hal::prelude::*;
 use k210_pac::{Peripherals, SPI0};
@@ -321,14 +321,14 @@ impl</*'a,*/ X: SPI> SDCard</*'a,*/ X> {
      * Get SD card data response.
      * @param  None
      * @retval The SD status: Read data response xxx0<status>1
-     *         - status 010: Data accecpted
+     *         - status 010: Data accepted
      *         - status 101: Data rejected due to a crc error
      *         - status 110: Data rejected due to a Write error.
      *         - status 111: Data rejected due to other error.
      */
     fn get_dataresponse(&self) -> u8 {
         let response = &mut [0u8];
-        /* Read resonse */
+        /* Read response */
         self.read_data(response);
         /* Mask unused bits */
         response[0] &= 0x1F;
@@ -423,7 +423,7 @@ impl</*'a,*/ X: SPI> SDCard</*'a,*/ X> {
             /* Byte 15 */
             CSD_CRC: (csd_tab[15] & 0xFE) >> 1,
             Reserved4: 1,
-            /* Return the reponse */
+            /* Return the response */
         })
     }
 
@@ -715,8 +715,8 @@ fn io_init() {
 }
 
 lazy_static! {
-    static ref PERIPHERALS: UPSafeCell<Peripherals> =
-        unsafe { UPSafeCell::new(Peripherals::take().unwrap()) };
+    static ref PERIPHERALS: UPIntrFreeCell<Peripherals> =
+        unsafe { UPIntrFreeCell::new(Peripherals::take().unwrap()) };
 }
 
 fn init_sdcard() -> SDCard<SPIImpl<SPI0>> {
@@ -740,11 +740,11 @@ fn init_sdcard() -> SDCard<SPIImpl<SPI0>> {
     sd
 }
 
-pub struct SDCardWrapper(UPSafeCell<SDCard<SPIImpl<SPI0>>>);
+pub struct SDCardWrapper(UPIntrFreeCell<SDCard<SPIImpl<SPI0>>>);
 
 impl SDCardWrapper {
     pub fn new() -> Self {
-        unsafe { Self(UPSafeCell::new(init_sdcard())) }
+        unsafe { Self(UPIntrFreeCell::new(init_sdcard())) }
     }
 }
 
@@ -761,4 +761,7 @@ impl BlockDevice for SDCardWrapper {
             .write_sector(buf, block_id as u32)
             .unwrap();
     }
+    fn handle_irq(&self) {
+        unimplemented!();
+    }
 }

os/src/drivers/block/virtio_blk.rs

@@ -3,42 +3,93 @@ use crate::mm::{
     frame_alloc, frame_dealloc, kernel_token, FrameTracker, PageTable, PhysAddr, PhysPageNum,
     StepByOne, VirtAddr,
 };
-use crate::sync::UPSafeCell;
+use crate::sync::{Condvar, UPIntrFreeCell};
+use crate::task::schedule;
+use crate::DEV_NON_BLOCKING_ACCESS;
+use alloc::collections::BTreeMap;
 use alloc::vec::Vec;
 use lazy_static::*;
-use virtio_drivers::{VirtIOBlk, VirtIOHeader};
+use virtio_drivers::{BlkResp, RespStatus, VirtIOBlk, VirtIOHeader};
 
 #[allow(unused)]
 const VIRTIO0: usize = 0x10001000;
 
-pub struct VirtIOBlock(UPSafeCell<VirtIOBlk<'static>>);
+pub struct VirtIOBlock {
+    virtio_blk: UPIntrFreeCell<VirtIOBlk<'static>>,
+    condvars: BTreeMap<u16, Condvar>,
+}
 
 lazy_static! {
-    static ref QUEUE_FRAMES: UPSafeCell<Vec<FrameTracker>> = unsafe { UPSafeCell::new(Vec::new()) };
+    static ref QUEUE_FRAMES: UPIntrFreeCell<Vec<FrameTracker>> =
+        unsafe { UPIntrFreeCell::new(Vec::new()) };
 }
 
 impl BlockDevice for VirtIOBlock {
     fn read_block(&self, block_id: usize, buf: &mut [u8]) {
-        self.0
-            .exclusive_access()
-            .read_block(block_id, buf)
-            .expect("Error when reading VirtIOBlk");
+        let nb = *DEV_NON_BLOCKING_ACCESS.exclusive_access();
+        if nb {
+            let mut resp = BlkResp::default();
+            let task_cx_ptr = self.virtio_blk.exclusive_session(|blk| {
+                let token = unsafe { blk.read_block_nb(block_id, buf, &mut resp).unwrap() };
+                self.condvars.get(&token).unwrap().wait_no_sched()
+            });
+            schedule(task_cx_ptr);
+            assert_eq!(
+                resp.status(),
+                RespStatus::Ok,
+                "Error when reading VirtIOBlk"
+            );
+        } else {
+            self.virtio_blk
+                .exclusive_access()
+                .read_block(block_id, buf)
+                .expect("Error when reading VirtIOBlk");
+        }
     }
     fn write_block(&self, block_id: usize, buf: &[u8]) {
-        self.0
-            .exclusive_access()
-            .write_block(block_id, buf)
-            .expect("Error when writing VirtIOBlk");
+        let nb = *DEV_NON_BLOCKING_ACCESS.exclusive_access();
+        if nb {
+            let mut resp = BlkResp::default();
+            let task_cx_ptr = self.virtio_blk.exclusive_session(|blk| {
+                let token = unsafe { blk.write_block_nb(block_id, buf, &mut resp).unwrap() };
+                self.condvars.get(&token).unwrap().wait_no_sched()
+            });
+            schedule(task_cx_ptr);
+            assert_eq!(
+                resp.status(),
+                RespStatus::Ok,
+                "Error when writing VirtIOBlk"
+            );
+        } else {
+            self.virtio_blk
+                .exclusive_access()
+                .write_block(block_id, buf)
+                .expect("Error when writing VirtIOBlk");
+        }
+    }
+    fn handle_irq(&self) {
+        self.virtio_blk.exclusive_session(|blk| {
+            while let Ok(token) = blk.pop_used() {
+                self.condvars.get(&token).unwrap().signal();
+            }
+        });
     }
 }
 
 impl VirtIOBlock {
-    #[allow(unused)]
     pub fn new() -> Self {
-        unsafe {
-            Self(UPSafeCell::new(
-                VirtIOBlk::new(&mut *(VIRTIO0 as *mut VirtIOHeader)).unwrap(),
-            ))
+        let virtio_blk = unsafe {
+            UPIntrFreeCell::new(VirtIOBlk::new(&mut *(VIRTIO0 as *mut VirtIOHeader)).unwrap())
+        };
+        let mut condvars = BTreeMap::new();
+        let channels = virtio_blk.exclusive_access().virt_queue_size();
+        for i in 0..channels {
+            let condvar = Condvar::new();
+            condvars.insert(i, condvar);
+        }
+        Self {
+            virtio_blk,
+            condvars,
         }
     }
 }

os/src/drivers/chardev/mod.rs

@@ -0,0 +1,17 @@
+mod ns16550a;
+
+pub use ns16550a::NS16550a;
+
+use crate::board::CharDeviceImpl;
+use alloc::sync::Arc;
+use lazy_static::*;
+
+pub trait CharDevice {
+    fn read(&self) -> u8;
+    fn write(&self, ch: u8);
+    fn handle_irq(&self);
+}
+
+lazy_static! {
+    pub static ref UART: Arc<CharDeviceImpl> = Arc::new(CharDeviceImpl::new());
+}

os/src/drivers/chardev/ns16550a.rs

@@ -0,0 +1,175 @@
+///! Ref: https://www.lammertbies.nl/comm/info/serial-uart
+///! Ref: ns16550a datasheet: https://datasheetspdf.com/pdf-file/605590/NationalSemiconductor/NS16550A/1
+///! Ref: ns16450 datasheet: https://datasheetspdf.com/pdf-file/1311818/NationalSemiconductor/NS16450/1
+use super::CharDevice;
+use crate::sync::{Condvar, UPIntrFreeCell};
+use crate::task::schedule;
+use alloc::collections::VecDeque;
+use bitflags::*;
+use volatile::{ReadOnly, Volatile, WriteOnly};
+
+bitflags! {
+    /// InterruptEnableRegister
+    pub struct IER: u8 {
+        const RX_AVAILABLE = 1 << 0;
+        const TX_EMPTY = 1 << 1;
+    }
+
+    /// LineStatusRegister
+    pub struct LSR: u8 {
+        const DATA_AVAILABLE = 1 << 0;
+        const THR_EMPTY = 1 << 5;
+    }
+
+    /// Model Control Register
+    pub struct MCR: u8 {
+        const DATA_TERMINAL_READY = 1 << 0;
+        const REQUEST_TO_SEND = 1 << 1;
+        const AUX_OUTPUT1 = 1 << 2;
+        const AUX_OUTPUT2 = 1 << 3;
+    }
+}
+
+#[repr(C)]
+#[allow(dead_code)]
+struct ReadWithoutDLAB {
+    /// receiver buffer register
+    pub rbr: ReadOnly<u8>,
+    /// interrupt enable register
+    pub ier: Volatile<IER>,
+    /// interrupt identification register
+    pub iir: ReadOnly<u8>,
+    /// line control register
+    pub lcr: Volatile<u8>,
+    /// model control register
+    pub mcr: Volatile<MCR>,
+    /// line status register
+    pub lsr: ReadOnly<LSR>,
+    /// ignore MSR
+    _padding1: ReadOnly<u8>,
+    /// ignore SCR
+    _padding2: ReadOnly<u8>,
+}
+
+#[repr(C)]
+#[allow(dead_code)]
+struct WriteWithoutDLAB {
+    /// transmitter holding register
+    pub thr: WriteOnly<u8>,
+    /// interrupt enable register
+    pub ier: Volatile<IER>,
+    /// ignore FCR
+    _padding0: ReadOnly<u8>,
+    /// line control register
+    pub lcr: Volatile<u8>,
+    /// modem control register
+    pub mcr: Volatile<MCR>,
+    /// line status register
+    pub lsr: ReadOnly<LSR>,
+    /// ignore other registers
+    _padding1: ReadOnly<u16>,
+}
+
+pub struct NS16550aRaw {
+    base_addr: usize,
+}
+
+impl NS16550aRaw {
+    fn read_end(&mut self) -> &mut ReadWithoutDLAB {
+        unsafe { &mut *(self.base_addr as *mut ReadWithoutDLAB) }
+    }
+
+    fn write_end(&mut self) -> &mut WriteWithoutDLAB {
+        unsafe { &mut *(self.base_addr as *mut WriteWithoutDLAB) }
+    }
+
+    pub fn new(base_addr: usize) -> Self {
+        Self { base_addr }
+    }
+
+    pub fn init(&mut self) {
+        let read_end = self.read_end();
+        let mut mcr = MCR::empty();
+        mcr |= MCR::DATA_TERMINAL_READY;
+        mcr |= MCR::REQUEST_TO_SEND;
+        mcr |= MCR::AUX_OUTPUT2;
+        read_end.mcr.write(mcr);
+        let ier = IER::RX_AVAILABLE;
+        read_end.ier.write(ier);
+    }
+
+    pub fn read(&mut self) -> Option<u8> {
+        let read_end = self.read_end();
+        let lsr = read_end.lsr.read();
+        if lsr.contains(LSR::DATA_AVAILABLE) {
+            Some(read_end.rbr.read())
+        } else {
+            None
+        }
+    }
+
+    pub fn write(&mut self, ch: u8) {
+        let write_end = self.write_end();
+        loop {
+            if write_end.lsr.read().contains(LSR::THR_EMPTY) {
+                write_end.thr.write(ch);
+                break;
+            }
+        }
+    }
+}
+
+struct NS16550aInner {
+    ns16550a: NS16550aRaw,
+    read_buffer: VecDeque<u8>,
+}
+
+pub struct NS16550a<const BASE_ADDR: usize> {
+    inner: UPIntrFreeCell<NS16550aInner>,
+    condvar: Condvar,
+}
+
+impl<const BASE_ADDR: usize> NS16550a<BASE_ADDR> {
+    pub fn new() -> Self {
+        let mut inner = NS16550aInner {
+            ns16550a: NS16550aRaw::new(BASE_ADDR),
+            read_buffer: VecDeque::new(),
+        };
+        inner.ns16550a.init();
+        Self {
+            inner: unsafe { UPIntrFreeCell::new(inner) },
+            condvar: Condvar::new(),
+        }
+    }
+}
+
+impl<const BASE_ADDR: usize> CharDevice for NS16550a<BASE_ADDR> {
+    fn read(&self) -> u8 {
+        loop {
+            let mut inner = self.inner.exclusive_access();
+            if let Some(ch) = inner.read_buffer.pop_front() {
+                return ch;
+            } else {
+                let task_cx_ptr = self.condvar.wait_no_sched();
+                drop(inner);
+                schedule(task_cx_ptr);
+            }
+        }
+    }
+    fn write(&self, ch: u8) {
+        let mut inner = self.inner.exclusive_access();
+        inner.ns16550a.write(ch);
+    }
+    fn handle_irq(&self) {
+        let mut count = 0;
+        self.inner.exclusive_session(|inner| {
+            while let Some(ch) = inner.ns16550a.read() {
+                count += 1;
+                inner.read_buffer.push_back(ch);
+            }
+        });
+        if count > 0 {
+            self.condvar.signal();
+        }
+    }
+}

os/src/drivers/mod.rs

@@ -1,3 +1,6 @@
 pub mod block;
+pub mod chardev;
+pub mod plic;
 
 pub use block::BLOCK_DEVICE;
+pub use chardev::UART;

os/src/drivers/plic.rs

@@ -0,0 +1,124 @@
+#[allow(clippy::upper_case_acronyms)]
+pub struct PLIC {
+    base_addr: usize,
+}
+
+#[derive(Copy, Clone)]
+pub enum IntrTargetPriority {
+    Machine = 0,
+    Supervisor = 1,
+}
+
+impl IntrTargetPriority {
+    pub fn supported_number() -> usize {
+        2
+    }
+}
+
+impl PLIC {
+    fn priority_ptr(&self, intr_source_id: usize) -> *mut u32 {
+        assert!(intr_source_id > 0 && intr_source_id <= 132);
+        (self.base_addr + intr_source_id * 4) as *mut u32
+    }
+    fn hart_id_with_priority(hart_id: usize, target_priority: IntrTargetPriority) -> usize {
+        let priority_num = IntrTargetPriority::supported_number();
+        hart_id * priority_num + target_priority as usize
+    }
+    fn enable_ptr(
+        &self,
+        hart_id: usize,
+        target_priority: IntrTargetPriority,
+        intr_source_id: usize,
+    ) -> (*mut u32, usize) {
+        let id = Self::hart_id_with_priority(hart_id, target_priority);
+        let (reg_id, reg_shift) = (intr_source_id / 32, intr_source_id % 32);
+        (
+            (self.base_addr + 0x2000 + 0x80 * id + 0x4 * reg_id) as *mut u32,
+            reg_shift,
+        )
+    }
+    fn threshold_ptr_of_hart_with_priority(
+        &self,
+        hart_id: usize,
+        target_priority: IntrTargetPriority,
+    ) -> *mut u32 {
+        let id = Self::hart_id_with_priority(hart_id, target_priority);
+        (self.base_addr + 0x20_0000 + 0x1000 * id) as *mut u32
+    }
+    fn claim_comp_ptr_of_hart_with_priority(
+        &self,
+        hart_id: usize,
+        target_priority: IntrTargetPriority,
+    ) -> *mut u32 {
+        let id = Self::hart_id_with_priority(hart_id, target_priority);
+        (self.base_addr + 0x20_0004 + 0x1000 * id) as *mut u32
+    }
+    pub unsafe fn new(base_addr: usize) -> Self {
+        Self { base_addr }
+    }
+    pub fn set_priority(&mut self, intr_source_id: usize, priority: u32) {
+        assert!(priority < 8);
+        unsafe {
+            self.priority_ptr(intr_source_id).write_volatile(priority);
+        }
+    }
+    #[allow(unused)]
+    pub fn get_priority(&mut self, intr_source_id: usize) -> u32 {
+        unsafe { self.priority_ptr(intr_source_id).read_volatile() & 7 }
+    }
+    pub fn enable(
+        &mut self,
+        hart_id: usize,
+        target_priority: IntrTargetPriority,
+        intr_source_id: usize,
+    ) {
+        let (reg_ptr, shift) = self.enable_ptr(hart_id, target_priority, intr_source_id);
+        unsafe {
+            reg_ptr.write_volatile(reg_ptr.read_volatile() | 1 << shift);
+        }
+    }
+    #[allow(unused)]
+    pub fn disable(
+        &mut self,
+        hart_id: usize,
+        target_priority: IntrTargetPriority,
+        intr_source_id: usize,
+    ) {
+        let (reg_ptr, shift) = self.enable_ptr(hart_id, target_priority, intr_source_id);
+        unsafe {
+            reg_ptr.write_volatile(reg_ptr.read_volatile() & (!(1u32 << shift)));
+        }
+    }
+    pub fn set_threshold(
+        &mut self,
+        hart_id: usize,
+        target_priority: IntrTargetPriority,
+        threshold: u32,
+    ) {
+        assert!(threshold < 8);
+        let threshold_ptr = self.threshold_ptr_of_hart_with_priority(hart_id, target_priority);
+        unsafe {
+            threshold_ptr.write_volatile(threshold);
+        }
+    }
+    #[allow(unused)]
+    pub fn get_threshold(&mut self, hart_id: usize, target_priority: IntrTargetPriority) -> u32 {
+        let threshold_ptr = self.threshold_ptr_of_hart_with_priority(hart_id, target_priority);
+        unsafe { threshold_ptr.read_volatile() & 7 }
+    }
+    pub fn claim(&mut self, hart_id: usize, target_priority: IntrTargetPriority) -> u32 {
+        let claim_comp_ptr = self.claim_comp_ptr_of_hart_with_priority(hart_id, target_priority);
+        unsafe { claim_comp_ptr.read_volatile() }
+    }
+    pub fn complete(
+        &mut self,
+        hart_id: usize,
+        target_priority: IntrTargetPriority,
+        completion: u32,
+    ) {
+        let claim_comp_ptr = self.claim_comp_ptr_of_hart_with_priority(hart_id, target_priority);
+        unsafe {
+            claim_comp_ptr.write_volatile(completion);
+        }
+    }
+}

os/src/entry.asm

@@ -9,4 +9,4 @@ _start:
 boot_stack:
     .space 4096 * 16
     .globl boot_stack_top
-boot_stack_top:
+boot_stack_top:

os/src/fs/inode.rs

@@ -1,7 +1,7 @@
 use super::File;
 use crate::drivers::BLOCK_DEVICE;
 use crate::mm::UserBuffer;
-use crate::sync::UPSafeCell;
+use crate::sync::UPIntrFreeCell;
 use alloc::sync::Arc;
 use alloc::vec::Vec;
 use bitflags::*;
@@ -11,7 +11,7 @@ use lazy_static::*;
 pub struct OSInode {
     readable: bool,
     writable: bool,
-    inner: UPSafeCell<OSInodeInner>,
+    inner: UPIntrFreeCell<OSInodeInner>,
 }
 
 pub struct OSInodeInner {
@@ -24,7 +24,7 @@ impl OSInode {
         Self {
             readable,
             writable,
-            inner: unsafe { UPSafeCell::new(OSInodeInner { offset: 0, inode }) },
+            inner: unsafe { UPIntrFreeCell::new(OSInodeInner { offset: 0, inode }) },
         }
     }
     pub fn read_all(&self) -> Vec<u8> {
@@ -55,7 +55,7 @@ pub fn list_apps() {
     for app in ROOT_INODE.ls() {
         println!("{}", app);
     }
-    println!("**************/");
+    println!("**************/")
 }
 
 bitflags! {

os/src/fs/pipe.rs

@@ -1,6 +1,6 @@
 use super::File;
 use crate::mm::UserBuffer;
-use crate::sync::UPSafeCell;
+use crate::sync::UPIntrFreeCell;
 use alloc::sync::{Arc, Weak};
 
 use crate::task::suspend_current_and_run_next;
@@ -8,18 +8,18 @@ use crate::task::suspend_current_and_run_next;
 pub struct Pipe {
     readable: bool,
     writable: bool,
-    buffer: Arc<UPSafeCell<PipeRingBuffer>>,
+    buffer: Arc<UPIntrFreeCell<PipeRingBuffer>>,
 }
 
 impl Pipe {
-    pub fn read_end_with_buffer(buffer: Arc<UPSafeCell<PipeRingBuffer>>) -> Self {
+    pub fn read_end_with_buffer(buffer: Arc<UPIntrFreeCell<PipeRingBuffer>>) -> Self {
         Self {
             readable: true,
             writable: false,
             buffer,
         }
     }
-    pub fn write_end_with_buffer(buffer: Arc<UPSafeCell<PipeRingBuffer>>) -> Self {
+    pub fn write_end_with_buffer(buffer: Arc<UPIntrFreeCell<PipeRingBuffer>>) -> Self {
         Self {
             readable: false,
             writable: true,
@@ -98,7 +98,7 @@ impl PipeRingBuffer {
 
 /// Return (read_end, write_end)
 pub fn make_pipe() -> (Arc<Pipe>, Arc<Pipe>) {
-    let buffer = Arc::new(unsafe { UPSafeCell::new(PipeRingBuffer::new()) });
+    let buffer = Arc::new(unsafe { UPIntrFreeCell::new(PipeRingBuffer::new()) });
     let read_end = Arc::new(Pipe::read_end_with_buffer(buffer.clone()));
     let write_end = Arc::new(Pipe::write_end_with_buffer(buffer.clone()));
     buffer.exclusive_access().set_write_end(&write_end);

os/src/fs/stdio.rs

@@ -1,10 +1,8 @@
 use super::File;
+use crate::drivers::chardev::{CharDevice, UART};
 use crate::mm::UserBuffer;
-use crate::sbi::console_getchar;
-use crate::task::suspend_current_and_run_next;
 
 pub struct Stdin;
-
 pub struct Stdout;
 
 impl File for Stdin {
@@ -16,18 +14,8 @@ impl File for Stdin {
     }
     fn read(&self, mut user_buf: UserBuffer) -> usize {
         assert_eq!(user_buf.len(), 1);
-        // busy loop
-        let mut c: usize;
-        loop {
-            c = console_getchar();
-            if c == 0 {
-                suspend_current_and_run_next();
-                continue;
-            } else {
-                break;
-            }
-        }
-        let ch = c as u8;
+        //println!("before UART.read() in Stdin::read()");
+        let ch = UART.read();
         unsafe {
             user_buf.buffers[0].as_mut_ptr().write_volatile(ch);
         }

os/src/lang_items.rs

@@ -1,4 +1,6 @@
 use crate::sbi::shutdown;
+use crate::task::current_kstack_top;
+use core::arch::asm;
 use core::panic::PanicInfo;
 
 #[panic_handler]
@@ -13,5 +15,23 @@ fn panic(info: &PanicInfo) -> ! {
     } else {
         println!("[kernel] Panicked: {}", info.message().unwrap());
     }
-    shutdown()
+    unsafe {
+        backtrace();
+    }
+    shutdown(255)
+}
+
+unsafe fn backtrace() {
+    let mut fp: usize;
+    let stop = current_kstack_top();
+    asm!("mv {}, s0", out(reg) fp);
+    println!("---START BACKTRACE---");
+    for i in 0..10 {
+        if fp == stop {
+            break;
+        }
+        println!("#{}:ra={:#x}", i, *((fp - 8) as *const usize));
+        fp = *((fp - 16) as *const usize);
+    }
+    println!("---END   BACKTRACE---");
 }

os/src/main.rs

@@ -29,9 +29,7 @@ mod task;
 mod timer;
 mod trap;
 
-use core::arch::global_asm;
-
-global_asm!(include_str!("entry.asm"));
+core::arch::global_asm!(include_str!("entry.asm"));
 
 fn clear_bss() {
     extern "C" {
@@ -44,17 +42,25 @@ fn clear_bss() {
     }
 }
 
+use lazy_static::*;
+use sync::UPIntrFreeCell;
+
+lazy_static! {
+    pub static ref DEV_NON_BLOCKING_ACCESS: UPIntrFreeCell<bool> =
+        unsafe { UPIntrFreeCell::new(false) };
+}
+
 #[no_mangle]
 pub fn rust_main() -> ! {
     clear_bss();
-    println!("[kernel] Hello, world!");
     mm::init();
-    mm::remap_test();
     trap::init();
     trap::enable_timer_interrupt();
     timer::set_next_trigger();
+    board::device_init();
     fs::list_apps();
     task::add_initproc();
+    *DEV_NON_BLOCKING_ACCESS.exclusive_access() = true;
     task::run_tasks();
     panic!("Unreachable in rust_main!");
 }

os/src/mm/address.rs

@@ -83,7 +83,11 @@ impl From<PhysPageNum> for usize {
 }
 impl From<VirtAddr> for usize {
     fn from(v: VirtAddr) -> Self {
-        v.0
+        if v.0 >= (1 << (VA_WIDTH_SV39 - 1)) {
+            v.0 | (!((1 << VA_WIDTH_SV39) - 1))
+        } else {
+            v.0
+        }
     }
 }
 impl From<VirtPageNum> for usize {

os/src/mm/frame_allocator.rs

@@ -1,6 +1,6 @@
 use super::{PhysAddr, PhysPageNum};
 use crate::config::MEMORY_END;
-use crate::sync::UPSafeCell;
+use crate::sync::UPIntrFreeCell;
 use alloc::vec::Vec;
 use core::fmt::{self, Debug, Formatter};
 use lazy_static::*;
@@ -83,8 +83,8 @@ impl FrameAllocator for StackFrameAllocator {
 type FrameAllocatorImpl = StackFrameAllocator;
 
 lazy_static! {
-    pub static ref FRAME_ALLOCATOR: UPSafeCell<FrameAllocatorImpl> =
-        unsafe { UPSafeCell::new(FrameAllocatorImpl::new()) };
+    pub static ref FRAME_ALLOCATOR: UPIntrFreeCell<FrameAllocatorImpl> =
+        unsafe { UPIntrFreeCell::new(FrameAllocatorImpl::new()) };
 }
 
 pub fn init_frame_allocator() {

os/src/mm/memory_set.rs

@@ -2,8 +2,8 @@ use super::{frame_alloc, FrameTracker};
 use super::{PTEFlags, PageTable, PageTableEntry};
 use super::{PhysAddr, PhysPageNum, VirtAddr, VirtPageNum};
 use super::{StepByOne, VPNRange};
-use crate::config::{MEMORY_END, MMIO, PAGE_SIZE, TRAMPOLINE, TRAP_CONTEXT, USER_STACK_SIZE};
-use crate::sync::UPSafeCell;
+use crate::config::{MEMORY_END, MMIO, PAGE_SIZE, TRAMPOLINE};
+use crate::sync::UPIntrFreeCell;
 use alloc::collections::BTreeMap;
 use alloc::sync::Arc;
 use alloc::vec::Vec;
@@ -25,8 +25,8 @@ extern "C" {
 }
 
 lazy_static! {
-    pub static ref KERNEL_SPACE: Arc<UPSafeCell<MemorySet>> =
-        Arc::new(unsafe { UPSafeCell::new(MemorySet::new_kernel()) });
+    pub static ref KERNEL_SPACE: Arc<UPIntrFreeCell<MemorySet>> =
+        Arc::new(unsafe { UPIntrFreeCell::new(MemorySet::new_kernel()) });
 }
 
 pub fn kernel_token() -> usize {
@@ -163,8 +163,8 @@ impl MemorySet {
         }
         memory_set
     }
-    /// Include sections in elf and trampoline and TrapContext and user stack,
-    /// also returns user_sp and entry point.
+    /// Include sections in elf and trampoline,
+    /// also returns user_sp_base and entry point.
     pub fn from_elf(elf_data: &[u8]) -> (Self, usize, usize) {
         let mut memory_set = Self::new_bare();
         // map trampoline
@@ -200,34 +200,12 @@ impl MemorySet {
                 );
             }
         }
-        // map user stack with U flags
         let max_end_va: VirtAddr = max_end_vpn.into();
-        let mut user_stack_bottom: usize = max_end_va.into();
-        // guard page
-        user_stack_bottom += PAGE_SIZE;
-        let user_stack_top = user_stack_bottom + USER_STACK_SIZE;
-        memory_set.push(
-            MapArea::new(
-                user_stack_bottom.into(),
-                user_stack_top.into(),
-                MapType::Framed,
-                MapPermission::R | MapPermission::W | MapPermission::U,
-            ),
-            None,
-        );
-        // map TrapContext
-        memory_set.push(
-            MapArea::new(
-                TRAP_CONTEXT.into(),
-                TRAMPOLINE.into(),
-                MapType::Framed,
-                MapPermission::R | MapPermission::W,
-            ),
-            None,
-        );
+        let mut user_stack_base: usize = max_end_va.into();
+        user_stack_base += PAGE_SIZE;
         (
             memory_set,
-            user_stack_top,
+            user_stack_base,
             elf.header.pt2.entry_point() as usize,
         )
     }
@@ -373,26 +351,20 @@ pub fn remap_test() {
     let mid_text: VirtAddr = ((stext as usize + etext as usize) / 2).into();
     let mid_rodata: VirtAddr = ((srodata as usize + erodata as usize) / 2).into();
     let mid_data: VirtAddr = ((sdata as usize + edata as usize) / 2).into();
-    assert!(
-        !kernel_space
-            .page_table
-            .translate(mid_text.floor())
-            .unwrap()
-            .writable(),
-    );
-    assert!(
-        !kernel_space
-            .page_table
-            .translate(mid_rodata.floor())
-            .unwrap()
-            .writable(),
-    );
-    assert!(
-        !kernel_space
-            .page_table
-            .translate(mid_data.floor())
-            .unwrap()
-            .executable(),
-    );
+    assert!(!kernel_space
+        .page_table
+        .translate(mid_text.floor())
+        .unwrap()
+        .writable(),);
+    assert!(!kernel_space
+        .page_table
+        .translate(mid_rodata.floor())
+        .unwrap()
+        .writable(),);
+    assert!(!kernel_space
+        .page_table
+        .translate(mid_data.floor())
+        .unwrap()
+        .executable(),);
     println!("remap_test passed!");
 }

os/src/sbi.rs

@@ -16,7 +16,7 @@ const SBI_SHUTDOWN: usize = 8;
 fn sbi_call(which: usize, arg0: usize, arg1: usize, arg2: usize) -> usize {
     let mut ret;
     unsafe {
-        asm!(
+        core::arch::asm!(
             "ecall",
             inlateout("x10") arg0 => ret,
             in("x11") arg1,
@@ -39,7 +39,9 @@ pub fn console_getchar() -> usize {
     sbi_call(SBI_CONSOLE_GETCHAR, 0, 0, 0)
 }
 
-pub fn shutdown() -> ! {
-    sbi_call(SBI_SHUTDOWN, 0, 0, 0);
+use crate::board::QEMUExit;
+pub fn shutdown(exit_code: usize) -> ! {
+    //sbi_call(SBI_SHUTDOWN, exit_code, 0, 0);
+    crate::board::QEMU_EXIT_HANDLE.exit_failure();
     panic!("It should shutdown!");
 }

os/src/sync/condvar.rs

@@ -0,0 +1,58 @@
+use crate::sync::{Mutex, UPIntrFreeCell};
+use crate::task::{
+    add_task, block_current_and_run_next, block_current_task, current_task, TaskContext,
+    TaskControlBlock,
+};
+use alloc::{collections::VecDeque, sync::Arc};
+
+pub struct Condvar {
+    pub inner: UPIntrFreeCell<CondvarInner>,
+}
+
+pub struct CondvarInner {
+    pub wait_queue: VecDeque<Arc<TaskControlBlock>>,
+}
+
+impl Condvar {
+    pub fn new() -> Self {
+        Self {
+            inner: unsafe {
+                UPIntrFreeCell::new(CondvarInner {
+                    wait_queue: VecDeque::new(),
+                })
+            },
+        }
+    }
+
+    pub fn signal(&self) {
+        let mut inner = self.inner.exclusive_access();
+        if let Some(task) = inner.wait_queue.pop_front() {
+            add_task(task);
+        }
+    }
+
+    /*
+    pub fn wait(&self) {
+        let mut inner = self.inner.exclusive_access();
+        inner.wait_queue.push_back(current_task().unwrap());
+        drop(inner);
+        block_current_and_run_next();
+    }
+    */
+
+    pub fn wait_no_sched(&self) -> *mut TaskContext {
+        self.inner.exclusive_session(|inner| {
+            inner.wait_queue.push_back(current_task().unwrap());
+        });
+        block_current_task()
+    }
+
+    pub fn wait_with_mutex(&self, mutex: Arc<dyn Mutex>) {
+        mutex.unlock();
+        self.inner.exclusive_session(|inner| {
+            inner.wait_queue.push_back(current_task().unwrap());
+        });
+        block_current_and_run_next();
+        mutex.lock();
+    }
+}

os/src/sync/mod.rs

@@ -1,3 +1,9 @@
+mod condvar;
+mod mutex;
+mod semaphore;
 mod up;
 
-pub use up::UPSafeCell;
+pub use condvar::Condvar;
+pub use mutex::{Mutex, MutexBlocking, MutexSpin};
+pub use semaphore::Semaphore;
+pub use up::{UPIntrFreeCell, UPIntrRefMut};

os/src/sync/mutex.rs

@@ -0,0 +1,88 @@
+use super::UPIntrFreeCell;
+use crate::task::TaskControlBlock;
+use crate::task::{add_task, current_task};
+use crate::task::{block_current_and_run_next, suspend_current_and_run_next};
+use alloc::{collections::VecDeque, sync::Arc};
+
+pub trait Mutex: Sync + Send {
+    fn lock(&self);
+    fn unlock(&self);
+}
+
+pub struct MutexSpin {
+    locked: UPIntrFreeCell<bool>,
+}
+
+impl MutexSpin {
+    pub fn new() -> Self {
+        Self {
+            locked: unsafe { UPIntrFreeCell::new(false) },
+        }
+    }
+}
+
+impl Mutex for MutexSpin {
+    fn lock(&self) {
+        loop {
+            let mut locked = self.locked.exclusive_access();
+            if *locked {
+                drop(locked);
+                suspend_current_and_run_next();
+                continue;
+            } else {
+                *locked = true;
+                return;
+            }
+        }
+    }
+
+    fn unlock(&self) {
+        let mut locked = self.locked.exclusive_access();
+        *locked = false;
+    }
+}
+
+pub struct MutexBlocking {
+    inner: UPIntrFreeCell<MutexBlockingInner>,
+}
+
+pub struct MutexBlockingInner {
+    locked: bool,
+    wait_queue: VecDeque<Arc<TaskControlBlock>>,
+}
+
+impl MutexBlocking {
+    pub fn new() -> Self {
+        Self {
+            inner: unsafe {
+                UPIntrFreeCell::new(MutexBlockingInner {
+                    locked: false,
+                    wait_queue: VecDeque::new(),
+                })
+            },
+        }
+    }
+}
+
+impl Mutex for MutexBlocking {
+    fn lock(&self) {
+        let mut mutex_inner = self.inner.exclusive_access();
+        if mutex_inner.locked {
+            mutex_inner.wait_queue.push_back(current_task().unwrap());
+            drop(mutex_inner);
+            block_current_and_run_next();
+        } else {
+            mutex_inner.locked = true;
+        }
+    }
+
+    fn unlock(&self) {
+        let mut mutex_inner = self.inner.exclusive_access();
+        assert!(mutex_inner.locked);
+        if let Some(waking_task) = mutex_inner.wait_queue.pop_front() {
+            add_task(waking_task);
+        } else {
+            mutex_inner.locked = false;
+        }
+    }
+}

os/src/sync/semaphore.rs

@@ -0,0 +1,45 @@
+use crate::sync::UPIntrFreeCell;
+use crate::task::{add_task, block_current_and_run_next, current_task, TaskControlBlock};
+use alloc::{collections::VecDeque, sync::Arc};
+
+pub struct Semaphore {
+    pub inner: UPIntrFreeCell<SemaphoreInner>,
+}
+
+pub struct SemaphoreInner {
+    pub count: isize,
+    pub wait_queue: VecDeque<Arc<TaskControlBlock>>,
+}
+
+impl Semaphore {
+    pub fn new(res_count: usize) -> Self {
+        Self {
+            inner: unsafe {
+                UPIntrFreeCell::new(SemaphoreInner {
+                    count: res_count as isize,
+                    wait_queue: VecDeque::new(),
+                })
+            },
+        }
+    }
+
+    pub fn up(&self) {
+        let mut inner = self.inner.exclusive_access();
+        inner.count += 1;
+        if inner.count <= 0 {
+            if let Some(task) = inner.wait_queue.pop_front() {
+                add_task(task);
+            }
+        }
+    }
+
+    pub fn down(&self) {
+        let mut inner = self.inner.exclusive_access();
+        inner.count -= 1;
+        if inner.count < 0 {
+            inner.wait_queue.push_back(current_task().unwrap());
+            drop(inner);
+            block_current_and_run_next();
+        }
+    }
+}

os/src/sync/up.rs

@@ -1,5 +1,9 @@
-use core::cell::{RefCell, RefMut};
+use core::cell::{RefCell, RefMut, UnsafeCell};
+use core::ops::{Deref, DerefMut};
+use lazy_static::*;
+use riscv::register::sstatus;
 
+/*
 /// Wrap a static data structure inside it so that we are
 /// able to access it without any `unsafe`.
 ///
@@ -27,3 +31,110 @@ impl<T> UPSafeCell<T> {
         self.inner.borrow_mut()
     }
 }
+*/
+
+pub struct UPSafeCellRaw<T> {
+    inner: UnsafeCell<T>,
+}
+
+unsafe impl<T> Sync for UPSafeCellRaw<T> {}
+
+impl<T> UPSafeCellRaw<T> {
+    pub unsafe fn new(value: T) -> Self {
+        Self {
+            inner: UnsafeCell::new(value),
+        }
+    }
+    pub fn get_mut(&self) -> &mut T {
+        unsafe { &mut (*self.inner.get()) }
+    }
+}
+
+pub struct IntrMaskingInfo {
+    nested_level: usize,
+    sie_before_masking: bool,
+}
+
+lazy_static! {
+    static ref INTR_MASKING_INFO: UPSafeCellRaw<IntrMaskingInfo> =
+        unsafe { UPSafeCellRaw::new(IntrMaskingInfo::new()) };
+}
+
+impl IntrMaskingInfo {
+    pub fn new() -> Self {
+        Self {
+            nested_level: 0,
+            sie_before_masking: false,
+        }
+    }
+
+    pub fn enter(&mut self) {
+        let sie = sstatus::read().sie();
+        unsafe {
+            sstatus::clear_sie();
+        }
+        if self.nested_level == 0 {
+            self.sie_before_masking = sie;
+        }
+        self.nested_level += 1;
+    }
+
+    pub fn exit(&mut self) {
+        self.nested_level -= 1;
+        if self.nested_level == 0 && self.sie_before_masking {
+            unsafe {
+                sstatus::set_sie();
+            }
+        }
+    }
+}
+
+pub struct UPIntrFreeCell<T> {
+    /// inner data
+    inner: RefCell<T>,
+}
+
+unsafe impl<T> Sync for UPIntrFreeCell<T> {}
+
+pub struct UPIntrRefMut<'a, T>(Option<RefMut<'a, T>>);
+
+impl<T> UPIntrFreeCell<T> {
+    pub unsafe fn new(value: T) -> Self {
+        Self {
+            inner: RefCell::new(value),
+        }
+    }
+
+    /// Panic if the data has been borrowed.
+    pub fn exclusive_access(&self) -> UPIntrRefMut<'_, T> {
+        INTR_MASKING_INFO.get_mut().enter();
+        UPIntrRefMut(Some(self.inner.borrow_mut()))
+    }
+
+    pub fn exclusive_session<F, V>(&self, f: F) -> V
+    where
+        F: FnOnce(&mut T) -> V,
+    {
+        let mut inner = self.exclusive_access();
+        f(inner.deref_mut())
+    }
+}
+
+impl<'a, T> Drop for UPIntrRefMut<'a, T> {
+    fn drop(&mut self) {
+        self.0 = None;
+        INTR_MASKING_INFO.get_mut().exit();
+    }
+}
+
+impl<'a, T> Deref for UPIntrRefMut<'a, T> {
+    type Target = T;
+    fn deref(&self) -> &Self::Target {
+        self.0.as_ref().unwrap().deref()
+    }
+}
+impl<'a, T> DerefMut for UPIntrRefMut<'a, T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        self.0.as_mut().unwrap().deref_mut()
+    }
+}

os/src/syscall/fs.rs

@@ -1,12 +1,12 @@
 use crate::fs::{make_pipe, open_file, OpenFlags};
 use crate::mm::{translated_byte_buffer, translated_refmut, translated_str, UserBuffer};
-use crate::task::{current_task, current_user_token};
+use crate::task::{current_process, current_user_token};
 use alloc::sync::Arc;
 
 pub fn sys_write(fd: usize, buf: *const u8, len: usize) -> isize {
     let token = current_user_token();
-    let task = current_task().unwrap();
-    let inner = task.inner_exclusive_access();
+    let process = current_process();
+    let inner = process.inner_exclusive_access();
     if fd >= inner.fd_table.len() {
         return -1;
     }
@@ -25,8 +25,8 @@ pub fn sys_write(fd: usize, buf: *const u8, len: usize) -> isize {
 
 pub fn sys_read(fd: usize, buf: *const u8, len: usize) -> isize {
     let token = current_user_token();
-    let task = current_task().unwrap();
-    let inner = task.inner_exclusive_access();
+    let process = current_process();
+    let inner = process.inner_exclusive_access();
     if fd >= inner.fd_table.len() {
         return -1;
     }
@@ -44,11 +44,11 @@ pub fn sys_read(fd: usize, buf: *const u8, len: usize) -> isize {
 }
 
 pub fn sys_open(path: *const u8, flags: u32) -> isize {
-    let task = current_task().unwrap();
+    let process = current_process();
     let token = current_user_token();
     let path = translated_str(token, path);
     if let Some(inode) = open_file(path.as_str(), OpenFlags::from_bits(flags).unwrap()) {
-        let mut inner = task.inner_exclusive_access();
+        let mut inner = process.inner_exclusive_access();
         let fd = inner.alloc_fd();
         inner.fd_table[fd] = Some(inode);
         fd as isize
@@ -58,8 +58,8 @@ pub fn sys_open(path: *const u8, flags: u32) -> isize {
 }
 
 pub fn sys_close(fd: usize) -> isize {
-    let task = current_task().unwrap();
-    let mut inner = task.inner_exclusive_access();
+    let process = current_process();
+    let mut inner = process.inner_exclusive_access();
     if fd >= inner.fd_table.len() {
         return -1;
     }
@@ -71,9 +71,9 @@ pub fn sys_close(fd: usize) -> isize {
 }
 
 pub fn sys_pipe(pipe: *mut usize) -> isize {
-    let task = current_task().unwrap();
+    let process = current_process();
     let token = current_user_token();
-    let mut inner = task.inner_exclusive_access();
+    let mut inner = process.inner_exclusive_access();
     let (pipe_read, pipe_write) = make_pipe();
     let read_fd = inner.alloc_fd();
     inner.fd_table[read_fd] = Some(pipe_read);
@@ -85,8 +85,8 @@ pub fn sys_pipe(pipe: *mut usize) -> isize {
 }
 
 pub fn sys_dup(fd: usize) -> isize {
-    let task = current_task().unwrap();
-    let mut inner = task.inner_exclusive_access();
+    let process = current_process();
+    let mut inner = process.inner_exclusive_access();
     if fd >= inner.fd_table.len() {
         return -1;
     }

os/src/syscall/mod.rs

@@ -5,24 +5,36 @@ const SYSCALL_PIPE: usize = 59;
 const SYSCALL_READ: usize = 63;
 const SYSCALL_WRITE: usize = 64;
 const SYSCALL_EXIT: usize = 93;
+const SYSCALL_SLEEP: usize = 101;
 const SYSCALL_YIELD: usize = 124;
 const SYSCALL_KILL: usize = 129;
-const SYSCALL_SIGACTION: usize = 134;
-const SYSCALL_SIGPROCMASK: usize = 135;
-const SYSCALL_SIGRETURN: usize = 139;
 const SYSCALL_GET_TIME: usize = 169;
 const SYSCALL_GETPID: usize = 172;
 const SYSCALL_FORK: usize = 220;
 const SYSCALL_EXEC: usize = 221;
 const SYSCALL_WAITPID: usize = 260;
+const SYSCALL_THREAD_CREATE: usize = 1000;
+const SYSCALL_GETTID: usize = 1001;
+const SYSCALL_WAITTID: usize = 1002;
+const SYSCALL_MUTEX_CREATE: usize = 1010;
+const SYSCALL_MUTEX_LOCK: usize = 1011;
+const SYSCALL_MUTEX_UNLOCK: usize = 1012;
+const SYSCALL_SEMAPHORE_CREATE: usize = 1020;
+const SYSCALL_SEMAPHORE_UP: usize = 1021;
+const SYSCALL_SEMAPHORE_DOWN: usize = 1022;
+const SYSCALL_CONDVAR_CREATE: usize = 1030;
+const SYSCALL_CONDVAR_SIGNAL: usize = 1031;
+const SYSCALL_CONDVAR_WAIT: usize = 1032;
 
 mod fs;
 mod process;
+mod sync;
+mod thread;
 
 use fs::*;
 use process::*;
-
-use crate::task::SignalAction;
+use sync::*;
+use thread::*;
 
 pub fn syscall(syscall_id: usize, args: [usize; 3]) -> isize {
     match syscall_id {
@@ -33,16 +45,26 @@ pub fn syscall(syscall_id: usize, args: [usize; 3]) -> isize {
         SYSCALL_READ => sys_read(args[0], args[1] as *const u8, args[2]),
         SYSCALL_WRITE => sys_write(args[0], args[1] as *const u8, args[2]),
         SYSCALL_EXIT => sys_exit(args[0] as i32),
+        SYSCALL_SLEEP => sys_sleep(args[0]),
         SYSCALL_YIELD => sys_yield(),
-        SYSCALL_KILL => sys_kill(args[0], args[1] as i32),
-        SYSCALL_SIGACTION => sys_sigaction(args[0] as i32, args[1] as *const SignalAction, args[2] as *mut SignalAction),
-        SYSCALL_SIGPROCMASK => sys_sigprocmask(args[0] as u32),
-        SYSCALL_SIGRETURN => sys_sigretrun(),
+        SYSCALL_KILL => sys_kill(args[0], args[1] as u32),
         SYSCALL_GET_TIME => sys_get_time(),
         SYSCALL_GETPID => sys_getpid(),
         SYSCALL_FORK => sys_fork(),
         SYSCALL_EXEC => sys_exec(args[0] as *const u8, args[1] as *const usize),
         SYSCALL_WAITPID => sys_waitpid(args[0] as isize, args[1] as *mut i32),
+        SYSCALL_THREAD_CREATE => sys_thread_create(args[0], args[1]),
+        SYSCALL_GETTID => sys_gettid(),
+        SYSCALL_WAITTID => sys_waittid(args[0]) as isize,
+        SYSCALL_MUTEX_CREATE => sys_mutex_create(args[0] == 1),
+        SYSCALL_MUTEX_LOCK => sys_mutex_lock(args[0]),
+        SYSCALL_MUTEX_UNLOCK => sys_mutex_unlock(args[0]),
+        SYSCALL_SEMAPHORE_CREATE => sys_semaphore_create(args[0]),
+        SYSCALL_SEMAPHORE_UP => sys_semaphore_up(args[0]),
+        SYSCALL_SEMAPHORE_DOWN => sys_semaphore_down(args[0]),
+        SYSCALL_CONDVAR_CREATE => sys_condvar_create(args[0]),
+        SYSCALL_CONDVAR_SIGNAL => sys_condvar_signal(args[0]),
+        SYSCALL_CONDVAR_WAIT => sys_condvar_wait(args[0], args[1]),
         _ => panic!("Unsupported syscall_id: {}", syscall_id),
     }
 }

os/src/syscall/process.rs

@@ -1,8 +1,8 @@
 use crate::fs::{open_file, OpenFlags};
 use crate::mm::{translated_ref, translated_refmut, translated_str};
 use crate::task::{
-    add_task, current_task, current_user_token, exit_current_and_run_next, pid2task,
-    suspend_current_and_run_next, SignalFlags, SignalAction, MAX_SIG,
+    current_process, current_task, current_user_token, exit_current_and_run_next, pid2process,
+    suspend_current_and_run_next, SignalFlags,
 };
 use crate::timer::get_time_ms;
 use alloc::string::String;
@@ -24,20 +24,20 @@ pub fn sys_get_time() -> isize {
 }
 
 pub fn sys_getpid() -> isize {
-    current_task().unwrap().pid.0 as isize
+    current_task().unwrap().process.upgrade().unwrap().getpid() as isize
 }
 
 pub fn sys_fork() -> isize {
-    let current_task = current_task().unwrap();
-    let new_task = current_task.fork();
-    let new_pid = new_task.pid.0;
+    let current_process = current_process();
+    let new_process = current_process.fork();
+    let new_pid = new_process.getpid();
     // modify trap context of new_task, because it returns immediately after switching
-    let trap_cx = new_task.inner_exclusive_access().get_trap_cx();
+    let new_process_inner = new_process.inner_exclusive_access();
+    let task = new_process_inner.tasks[0].as_ref().unwrap();
+    let trap_cx = task.inner_exclusive_access().get_trap_cx();
     // we do not have to move to next instruction since we have done it before
     // for child process, fork returns 0
     trap_cx.x[10] = 0;
-    // add new task to scheduler
-    add_task(new_task);
     new_pid as isize
 }
 
@@ -57,9 +57,9 @@ pub fn sys_exec(path: *const u8, mut args: *const usize) -> isize {
     }
     if let Some(app_inode) = open_file(path.as_str(), OpenFlags::RDONLY) {
         let all_data = app_inode.read_all();
-        let task = current_task().unwrap();
+        let process = current_process();
         let argc = args_vec.len();
-        task.exec(all_data.as_slice(), args_vec);
+        process.exec(all_data.as_slice(), args_vec);
         // return argc because cx.x[10] will be covered with it later
         argc as isize
     } else {
@@ -70,11 +70,10 @@ pub fn sys_exec(path: *const u8, mut args: *const usize) -> isize {
 /// If there is not a child process whose pid is same as given, return -1.
 /// Else if there is a child process but it is still running, return -2.
 pub fn sys_waitpid(pid: isize, exit_code_ptr: *mut i32) -> isize {
-    let task = current_task().unwrap();
+    let process = current_process();
     // find a child process
 
-    // ---- access current PCB exclusively
-    let mut inner = task.inner_exclusive_access();
+    let mut inner = process.inner_exclusive_access();
     if !inner
         .children
         .iter()
@@ -85,7 +84,7 @@ pub fn sys_waitpid(pid: isize, exit_code_ptr: *mut i32) -> isize {
     }
     let pair = inner.children.iter().enumerate().find(|(_, p)| {
         // ++++ temporarily access child PCB exclusively
-        p.inner_exclusive_access().is_zombie() && (pid == -1 || pid as usize == p.getpid())
+        p.inner_exclusive_access().is_zombie && (pid == -1 || pid as usize == p.getpid())
         // ++++ release child PCB
     });
     if let Some((idx, _)) = pair {
@@ -104,15 +103,10 @@ pub fn sys_waitpid(pid: isize, exit_code_ptr: *mut i32) -> isize {
     // ---- release current PCB automatically
 }
 
-pub fn sys_kill(pid: usize, signum: i32) -> isize {
-    if let Some(task) = pid2task(pid) {
-        if let Some(flag) = SignalFlags::from_bits(1 << signum) {
-            // insert the signal if legal
-            let mut task_ref = task.inner_exclusive_access();
-            if task_ref.signals.contains(flag) {
-                return -1;
-            }
-            task_ref.signals.insert(flag);
+pub fn sys_kill(pid: usize, signal: u32) -> isize {
+    if let Some(process) = pid2process(pid) {
+        if let Some(flag) = SignalFlags::from_bits(signal) {
+            process.inner_exclusive_access().signals |= flag;
             0
         } else {
             -1
@@ -121,66 +115,3 @@ pub fn sys_kill(pid: usize, signum: i32) -> isize {
         -1
     }
 }
-
-pub fn sys_sigprocmask(mask: u32) -> isize {
-    if let Some(task) = current_task() {
-        let mut inner = task.inner_exclusive_access();
-        let old_mask = inner.signal_mask;
-        if let Some(flag) = SignalFlags::from_bits(mask) {
-            inner.signal_mask = flag;
-            old_mask.bits() as isize
-        } else {
-            -1
-        }
-    } else {
-        -1
-    }
-}
-
-pub fn sys_sigretrun() -> isize {
-    if let Some(task) = current_task() {
-        let mut inner = task.inner_exclusive_access();
-        inner.handling_sig = -1;
-        // restore the trap context
-        let trap_ctx = inner.get_trap_cx();
-        *trap_ctx = inner.trap_ctx_backup.unwrap();
-        0
-    } else {
-        -1
-    }
-}
-
-fn check_sigaction_error(signal: SignalFlags, action: usize, old_action: usize) -> bool {
-    if action == 0 || old_action == 0 || signal == SignalFlags::SIGKILL ||
-        signal == SignalFlags::SIGSTOP {
-        true
-    } else {
-        false
-    }
-}
-
-pub fn sys_sigaction(signum: i32, action: *const SignalAction, old_action: *mut SignalAction) -> isize {
-    let token = current_user_token();
-    if let Some(task) = current_task() {
-        let mut inner = task.inner_exclusive_access();
-        if signum as usize > MAX_SIG {
-            return -1;
-        }
-        if let Some(flag) = SignalFlags::from_bits(1 << signum) {
-            if check_sigaction_error(flag, action as usize, old_action as usize) {
-                return -1;
-            }
-            let old_kernel_action = inner.signal_actions.table[signum as usize];
-            if old_kernel_action.mask != SignalFlags::from_bits(40).unwrap() {
-                *translated_refmut(token, old_action) = old_kernel_action;
-            } else {
-                let mut ref_old_action = *translated_refmut(token, old_action);
-                ref_old_action.handler = old_kernel_action.handler;
-            }
-            let ref_action = translated_ref(token, action);
-            inner.signal_actions.table[signum as usize] = *ref_action;
-            return 0;
-        }
-    }
-    -1
-}

os/src/syscall/sync.rs

@@ -0,0 +1,134 @@
+use crate::sync::{Condvar, Mutex, MutexBlocking, MutexSpin, Semaphore};
+use crate::task::{block_current_and_run_next, current_process, current_task};
+use crate::timer::{add_timer, get_time_ms};
+use alloc::sync::Arc;
+
+pub fn sys_sleep(ms: usize) -> isize {
+    let expire_ms = get_time_ms() + ms;
+    let task = current_task().unwrap();
+    add_timer(expire_ms, task);
+    block_current_and_run_next();
+    0
+}
+
+pub fn sys_mutex_create(blocking: bool) -> isize {
+    let process = current_process();
+    let mutex: Option<Arc<dyn Mutex>> = if !blocking {
+        Some(Arc::new(MutexSpin::new()))
+    } else {
+        Some(Arc::new(MutexBlocking::new()))
+    };
+    let mut process_inner = process.inner_exclusive_access();
+    if let Some(id) = process_inner
+        .mutex_list
+        .iter()
+        .enumerate()
+        .find(|(_, item)| item.is_none())
+        .map(|(id, _)| id)
+    {
+        process_inner.mutex_list[id] = mutex;
+        id as isize
+    } else {
+        process_inner.mutex_list.push(mutex);
+        process_inner.mutex_list.len() as isize - 1
+    }
+}
+
+pub fn sys_mutex_lock(mutex_id: usize) -> isize {
+    let process = current_process();
+    let process_inner = process.inner_exclusive_access();
+    let mutex = Arc::clone(process_inner.mutex_list[mutex_id].as_ref().unwrap());
+    drop(process_inner);
+    drop(process);
+    mutex.lock();
+    0
+}
+
+pub fn sys_mutex_unlock(mutex_id: usize) -> isize {
+    let process = current_process();
+    let process_inner = process.inner_exclusive_access();
+    let mutex = Arc::clone(process_inner.mutex_list[mutex_id].as_ref().unwrap());
+    drop(process_inner);
+    drop(process);
+    mutex.unlock();
+    0
+}
+
+pub fn sys_semaphore_create(res_count: usize) -> isize {
+    let process = current_process();
+    let mut process_inner = process.inner_exclusive_access();
+    let id = if let Some(id) = process_inner
+        .semaphore_list
+        .iter()
+        .enumerate()
+        .find(|(_, item)| item.is_none())
+        .map(|(id, _)| id)
+    {
+        process_inner.semaphore_list[id] = Some(Arc::new(Semaphore::new(res_count)));
+        id
+    } else {
+        process_inner
+            .semaphore_list
+            .push(Some(Arc::new(Semaphore::new(res_count))));
+        process_inner.semaphore_list.len() - 1
+    };
+    id as isize
+}
+
+pub fn sys_semaphore_up(sem_id: usize) -> isize {
+    let process = current_process();
+    let process_inner = process.inner_exclusive_access();
+    let sem = Arc::clone(process_inner.semaphore_list[sem_id].as_ref().unwrap());
+    drop(process_inner);
+    sem.up();
+    0
+}
+
+pub fn sys_semaphore_down(sem_id: usize) -> isize {
+    let process = current_process();
+    let process_inner = process.inner_exclusive_access();
+    let sem = Arc::clone(process_inner.semaphore_list[sem_id].as_ref().unwrap());
+    drop(process_inner);
+    sem.down();
+    0
+}
+
+pub fn sys_condvar_create(_arg: usize) -> isize {
+    let process = current_process();
+    let mut process_inner = process.inner_exclusive_access();
+    let id = if let Some(id) = process_inner
+        .condvar_list
+        .iter()
+        .enumerate()
+        .find(|(_, item)| item.is_none())
+        .map(|(id, _)| id)
+    {
+        process_inner.condvar_list[id] = Some(Arc::new(Condvar::new()));
+        id
+    } else {
+        process_inner
+            .condvar_list
+            .push(Some(Arc::new(Condvar::new())));
+        process_inner.condvar_list.len() - 1
+    };
+    id as isize
+}
+
+pub fn sys_condvar_signal(condvar_id: usize) -> isize {
+    let process = current_process();
+    let process_inner = process.inner_exclusive_access();
+    let condvar = Arc::clone(process_inner.condvar_list[condvar_id].as_ref().unwrap());
+    drop(process_inner);
+    condvar.signal();
+    0
+}
+
+pub fn sys_condvar_wait(condvar_id: usize, mutex_id: usize) -> isize {
+    let process = current_process();
+    let process_inner = process.inner_exclusive_access();
+    let condvar = Arc::clone(process_inner.condvar_list[condvar_id].as_ref().unwrap());
+    let mutex = Arc::clone(process_inner.mutex_list[mutex_id].as_ref().unwrap());
+    drop(process_inner);
+    condvar.wait_with_mutex(mutex);
+    0
+}

os/src/syscall/thread.rs

@@ -0,0 +1,85 @@
+use crate::{
+    mm::kernel_token,
+    task::{add_task, current_task, TaskControlBlock},
+    trap::{trap_handler, TrapContext},
+};
+use alloc::sync::Arc;
+
+pub fn sys_thread_create(entry: usize, arg: usize) -> isize {
+    let task = current_task().unwrap();
+    let process = task.process.upgrade().unwrap();
+    // create a new thread
+    let new_task = Arc::new(TaskControlBlock::new(
+        Arc::clone(&process),
+        task.inner_exclusive_access()
+            .res
+            .as_ref()
+            .unwrap()
+            .ustack_base,
+        true,
+    ));
+    // add new task to scheduler
+    add_task(Arc::clone(&new_task));
+    let new_task_inner = new_task.inner_exclusive_access();
+    let new_task_res = new_task_inner.res.as_ref().unwrap();
+    let new_task_tid = new_task_res.tid;
+    let mut process_inner = process.inner_exclusive_access();
+    // add new thread to current process
+    let tasks = &mut process_inner.tasks;
+    while tasks.len() < new_task_tid + 1 {
+        tasks.push(None);
+    }
+    tasks[new_task_tid] = Some(Arc::clone(&new_task));
+    let new_task_trap_cx = new_task_inner.get_trap_cx();
+    *new_task_trap_cx = TrapContext::app_init_context(
+        entry,
+        new_task_res.ustack_top(),
+        kernel_token(),
+        new_task.kstack.get_top(),
+        trap_handler as usize,
+    );
+    (*new_task_trap_cx).x[10] = arg;
+    new_task_tid as isize
+}
+
+pub fn sys_gettid() -> isize {
+    current_task()
+        .unwrap()
+        .inner_exclusive_access()
+        .res
+        .as_ref()
+        .unwrap()
+        .tid as isize
+}
+
+/// thread does not exist, return -1
+/// thread has not exited yet, return -2
+/// otherwise, return thread's exit code
+pub fn sys_waittid(tid: usize) -> i32 {
+    let task = current_task().unwrap();
+    let process = task.process.upgrade().unwrap();
+    let task_inner = task.inner_exclusive_access();
+    let mut process_inner = process.inner_exclusive_access();
+    // a thread cannot wait for itself
+    if task_inner.res.as_ref().unwrap().tid == tid {
+        return -1;
+    }
+    let mut exit_code: Option<i32> = None;
+    let waited_task = process_inner.tasks[tid].as_ref();
+    if let Some(waited_task) = waited_task {
+        if let Some(waited_exit_code) = waited_task.inner_exclusive_access().exit_code {
+            exit_code = Some(waited_exit_code);
+        }
+    } else {
+        // waited thread does not exist
+        return -1;
+    }
+    if let Some(exit_code) = exit_code {
+        // dealloc the exited thread
+        process_inner.tasks[tid] = None;
+        exit_code
+    } else {
+        // waited thread has not exited
+        -2
+    }
+}

os/src/task/action.rs

@@ -1,32 +0,0 @@
-use crate::task::{SignalFlags, MAX_SIG};
-
-
-/// Action for a signal
-#[repr(C)]
-#[derive(Debug, Clone, Copy)]
-pub struct SignalAction {
-    pub handler: usize, 
-    pub mask: SignalFlags
-}
-
-impl Default for SignalAction {
-    fn default() -> Self {
-        Self {
-            handler: 0,
-            mask: SignalFlags::from_bits(40).unwrap()
-        }
-    }
-}
-
-#[derive(Clone)]
-pub struct SignalActions {
-    pub table: [SignalAction; MAX_SIG + 1],
-}
-
-impl Default for SignalActions {
-    fn default() -> Self {
-        Self {
-            table: [SignalAction::default(); MAX_SIG + 1],
-        }
-    }
-}

os/src/task/id.rs

@@ -0,0 +1,225 @@
+use super::ProcessControlBlock;
+use crate::config::{KERNEL_STACK_SIZE, PAGE_SIZE, TRAMPOLINE, TRAP_CONTEXT_BASE, USER_STACK_SIZE};
+use crate::mm::{MapPermission, PhysPageNum, VirtAddr, KERNEL_SPACE};
+use crate::sync::UPIntrFreeCell;
+use alloc::{
+    sync::{Arc, Weak},
+    vec::Vec,
+};
+use lazy_static::*;
+
+pub struct RecycleAllocator {
+    current: usize,
+    recycled: Vec<usize>,
+}
+
+impl RecycleAllocator {
+    pub fn new() -> Self {
+        RecycleAllocator {
+            current: 0,
+            recycled: Vec::new(),
+        }
+    }
+    pub fn alloc(&mut self) -> usize {
+        if let Some(id) = self.recycled.pop() {
+            id
+        } else {
+            self.current += 1;
+            self.current - 1
+        }
+    }
+    pub fn dealloc(&mut self, id: usize) {
+        assert!(id < self.current);
+        assert!(
+            !self.recycled.iter().any(|i| *i == id),
+            "id {} has been deallocated!",
+            id
+        );
+        self.recycled.push(id);
+    }
+}
+
+lazy_static! {
+    static ref PID_ALLOCATOR: UPIntrFreeCell<RecycleAllocator> =
+        unsafe { UPIntrFreeCell::new(RecycleAllocator::new()) };
+    static ref KSTACK_ALLOCATOR: UPIntrFreeCell<RecycleAllocator> =
+        unsafe { UPIntrFreeCell::new(RecycleAllocator::new()) };
+}
+
+pub const IDLE_PID: usize = 0;
+
+pub struct PidHandle(pub usize);
+
+pub fn pid_alloc() -> PidHandle {
+    PidHandle(PID_ALLOCATOR.exclusive_access().alloc())
+}
+
+impl Drop for PidHandle {
+    fn drop(&mut self) {
+        PID_ALLOCATOR.exclusive_access().dealloc(self.0);
+    }
+}
+
+/// Return (bottom, top) of a kernel stack in kernel space.
+pub fn kernel_stack_position(kstack_id: usize) -> (usize, usize) {
+    let top = TRAMPOLINE - kstack_id * (KERNEL_STACK_SIZE + PAGE_SIZE);
+    let bottom = top - KERNEL_STACK_SIZE;
+    (bottom, top)
+}
+
+pub struct KernelStack(pub usize);
+
+pub fn kstack_alloc() -> KernelStack {
+    let kstack_id = KSTACK_ALLOCATOR.exclusive_access().alloc();
+    let (kstack_bottom, kstack_top) = kernel_stack_position(kstack_id);
+    KERNEL_SPACE.exclusive_access().insert_framed_area(
+        kstack_bottom.into(),
+        kstack_top.into(),
+        MapPermission::R | MapPermission::W,
+    );
+    KernelStack(kstack_id)
+}
+
+impl Drop for KernelStack {
+    fn drop(&mut self) {
+        let (kernel_stack_bottom, _) = kernel_stack_position(self.0);
+        let kernel_stack_bottom_va: VirtAddr = kernel_stack_bottom.into();
+        KERNEL_SPACE
+            .exclusive_access()
+            .remove_area_with_start_vpn(kernel_stack_bottom_va.into());
+    }
+}
+
+impl KernelStack {
+    #[allow(unused)]
+    pub fn push_on_top<T>(&self, value: T) -> *mut T
+    where
+        T: Sized,
+    {
+        let kernel_stack_top = self.get_top();
+        let ptr_mut = (kernel_stack_top - core::mem::size_of::<T>()) as *mut T;
+        unsafe {
+            *ptr_mut = value;
+        }
+        ptr_mut
+    }
+    pub fn get_top(&self) -> usize {
+        let (_, kernel_stack_top) = kernel_stack_position(self.0);
+        kernel_stack_top
+    }
+}
+
+pub struct TaskUserRes {
+    pub tid: usize,
+    pub ustack_base: usize,
+    pub process: Weak<ProcessControlBlock>,
+}
+
+fn trap_cx_bottom_from_tid(tid: usize) -> usize {
+    TRAP_CONTEXT_BASE - tid * PAGE_SIZE
+}
+
+fn ustack_bottom_from_tid(ustack_base: usize, tid: usize) -> usize {
+    ustack_base + tid * (PAGE_SIZE + USER_STACK_SIZE)
+}
+
+impl TaskUserRes {
+    pub fn new(
+        process: Arc<ProcessControlBlock>,
+        ustack_base: usize,
+        alloc_user_res: bool,
+    ) -> Self {
+        let tid = process.inner_exclusive_access().alloc_tid();
+        let task_user_res = Self {
+            tid,
+            ustack_base,
+            process: Arc::downgrade(&process),
+        };
+        if alloc_user_res {
+            task_user_res.alloc_user_res();
+        }
+        task_user_res
+    }
+
+    pub fn alloc_user_res(&self) {
+        let process = self.process.upgrade().unwrap();
+        let mut process_inner = process.inner_exclusive_access();
+        // alloc user stack
+        let ustack_bottom = ustack_bottom_from_tid(self.ustack_base, self.tid);
+        let ustack_top = ustack_bottom + USER_STACK_SIZE;
+        process_inner.memory_set.insert_framed_area(
+            ustack_bottom.into(),
+            ustack_top.into(),
+            MapPermission::R | MapPermission::W | MapPermission::U,
+        );
+        // alloc trap_cx
+        let trap_cx_bottom = trap_cx_bottom_from_tid(self.tid);
+        let trap_cx_top = trap_cx_bottom + PAGE_SIZE;
+        process_inner.memory_set.insert_framed_area(
+            trap_cx_bottom.into(),
+            trap_cx_top.into(),
+            MapPermission::R | MapPermission::W,
+        );
+    }
+
+    fn dealloc_user_res(&self) {
+        // dealloc tid
+        let process = self.process.upgrade().unwrap();
+        let mut process_inner = process.inner_exclusive_access();
+        // dealloc ustack manually
+        let ustack_bottom_va: VirtAddr = ustack_bottom_from_tid(self.ustack_base, self.tid).into();
+        process_inner
+            .memory_set
+            .remove_area_with_start_vpn(ustack_bottom_va.into());
+        // dealloc trap_cx manually
+        let trap_cx_bottom_va: VirtAddr = trap_cx_bottom_from_tid(self.tid).into();
+        process_inner
+            .memory_set
+            .remove_area_with_start_vpn(trap_cx_bottom_va.into());
+    }
+
+    #[allow(unused)]
+    pub fn alloc_tid(&mut self) {
+        self.tid = self
+            .process
+            .upgrade()
+            .unwrap()
+            .inner_exclusive_access()
+            .alloc_tid();
+    }
+
+    pub fn dealloc_tid(&self) {
+        let process = self.process.upgrade().unwrap();
+        let mut process_inner = process.inner_exclusive_access();
+        process_inner.dealloc_tid(self.tid);
+    }
+
+    pub fn trap_cx_user_va(&self) -> usize {
+        trap_cx_bottom_from_tid(self.tid)
+    }
+
+    pub fn trap_cx_ppn(&self) -> PhysPageNum {
+        let process = self.process.upgrade().unwrap();
+        let process_inner = process.inner_exclusive_access();
+        let trap_cx_bottom_va: VirtAddr = trap_cx_bottom_from_tid(self.tid).into();
+        process_inner
+            .memory_set
+            .translate(trap_cx_bottom_va.into())
+            .unwrap()
+            .ppn()
+    }
+
+    pub fn ustack_base(&self) -> usize {
+        self.ustack_base
+    }
+    pub fn ustack_top(&self) -> usize {
+        ustack_bottom_from_tid(self.ustack_base, self.tid) + USER_STACK_SIZE
+    }
+}
+
+impl Drop for TaskUserRes {
+    fn drop(&mut self) {
+        self.dealloc_tid();
+        self.dealloc_user_res();
+    }
+}

os/src/task/manager.rs

@@ -1,5 +1,5 @@
-use super::TaskControlBlock;
-use crate::sync::UPSafeCell;
+use super::{ProcessControlBlock, TaskControlBlock};
+use crate::sync::UPIntrFreeCell;
 use alloc::collections::{BTreeMap, VecDeque};
 use alloc::sync::Arc;
 use lazy_static::*;
@@ -24,16 +24,13 @@ impl TaskManager {
 }
 
 lazy_static! {
-    pub static ref TASK_MANAGER: UPSafeCell<TaskManager> =
-        unsafe { UPSafeCell::new(TaskManager::new()) };
-    pub static ref PID2TCB: UPSafeCell<BTreeMap<usize, Arc<TaskControlBlock>>> =
-        unsafe { UPSafeCell::new(BTreeMap::new()) };
+    pub static ref TASK_MANAGER: UPIntrFreeCell<TaskManager> =
+        unsafe { UPIntrFreeCell::new(TaskManager::new()) };
+    pub static ref PID2PCB: UPIntrFreeCell<BTreeMap<usize, Arc<ProcessControlBlock>>> =
+        unsafe { UPIntrFreeCell::new(BTreeMap::new()) };
 }
 
 pub fn add_task(task: Arc<TaskControlBlock>) {
-    PID2TCB
-        .exclusive_access()
-        .insert(task.getpid(), Arc::clone(&task));
     TASK_MANAGER.exclusive_access().add(task);
 }
 
@@ -41,13 +38,17 @@ pub fn fetch_task() -> Option<Arc<TaskControlBlock>> {
     TASK_MANAGER.exclusive_access().fetch()
 }
 
-pub fn pid2task(pid: usize) -> Option<Arc<TaskControlBlock>> {
-    let map = PID2TCB.exclusive_access();
+pub fn pid2process(pid: usize) -> Option<Arc<ProcessControlBlock>> {
+    let map = PID2PCB.exclusive_access();
     map.get(&pid).map(Arc::clone)
 }
 
-pub fn remove_from_pid2task(pid: usize) {
-    let mut map = PID2TCB.exclusive_access();
+pub fn insert_into_pid2process(pid: usize, process: Arc<ProcessControlBlock>) {
+    PID2PCB.exclusive_access().insert(pid, process);
+}
+
+pub fn remove_from_pid2process(pid: usize) {
+    let mut map = PID2PCB.exclusive_access();
     if map.remove(&pid).is_none() {
         panic!("cannot find pid {} in pid2task!", pid);
     }

os/src/task/mod.rs

@@ -1,30 +1,30 @@
 mod context;
+mod id;
 mod manager;
-mod pid;
+mod process;
 mod processor;
 mod signal;
 mod switch;
-mod action;
 #[allow(clippy::module_inception)]
 mod task;
 
+use self::id::TaskUserRes;
 use crate::fs::{open_file, OpenFlags};
-use alloc::sync::Arc;
-pub use context::TaskContext;
+use alloc::{sync::Arc, vec::Vec};
 use lazy_static::*;
 use manager::fetch_task;
-use manager::remove_from_pid2task;
+use process::ProcessControlBlock;
 use switch::__switch;
-use task::{TaskControlBlock, TaskStatus};
 
-pub use manager::{add_task, pid2task};
-pub use pid::{pid_alloc, KernelStack, PidHandle};
+pub use context::TaskContext;
+pub use id::{kstack_alloc, pid_alloc, KernelStack, PidHandle, IDLE_PID};
+pub use manager::{add_task, pid2process, remove_from_pid2process};
 pub use processor::{
-    current_task, current_trap_cx, current_user_token, run_tasks, schedule, take_current_task,
+    current_kstack_top, current_process, current_task, current_trap_cx, current_trap_cx_user_va,
+    current_user_token, run_tasks, schedule, take_current_task,
 };
-pub use signal::{SignalFlags, MAX_SIG};
-pub use action::{SignalAction, SignalActions};
-
+pub use signal::SignalFlags;
+pub use task::{TaskControlBlock, TaskStatus};
 
 pub fn suspend_current_and_run_next() {
     // There must be an application running.
@@ -36,7 +36,7 @@ pub fn suspend_current_and_run_next() {
     // Change status to Ready
     task_inner.task_status = TaskStatus::Ready;
     drop(task_inner);
-    // ---- release current PCB
+    // ---- release current TCB
 
     // push back to ready queue.
     add_task(task);
@@ -44,159 +44,116 @@ pub fn suspend_current_and_run_next() {
     schedule(task_cx_ptr);
 }
 
+/// This function must be followed by a schedule
+pub fn block_current_task() -> *mut TaskContext {
+    let task = take_current_task().unwrap();
+    let mut task_inner = task.inner_exclusive_access();
+    task_inner.task_status = TaskStatus::Blocking;
+    &mut task_inner.task_cx as *mut TaskContext
+}
+
+pub fn block_current_and_run_next() {
+    let task_cx_ptr = block_current_task();
+    schedule(task_cx_ptr);
+}
+
+use crate::board::QEMUExit;
+
 pub fn exit_current_and_run_next(exit_code: i32) {
-    // take from Processor
     let task = take_current_task().unwrap();
-    // remove from pid2task
-    remove_from_pid2task(task.getpid());
-    // **** access current TCB exclusively
-    let mut inner = task.inner_exclusive_access();
-    // Change status to Zombie
-    inner.task_status = TaskStatus::Zombie;
-    // Record exit code
-    inner.exit_code = exit_code;
-    // do not move to its parent but under initproc
-
-    // ++++++ access initproc TCB exclusively
-    {
-        let mut initproc_inner = INITPROC.inner_exclusive_access();
-        for child in inner.children.iter() {
-            child.inner_exclusive_access().parent = Some(Arc::downgrade(&INITPROC));
-            initproc_inner.children.push(child.clone());
+    let mut task_inner = task.inner_exclusive_access();
+    let process = task.process.upgrade().unwrap();
+    let tid = task_inner.res.as_ref().unwrap().tid;
+    // record exit code
+    task_inner.exit_code = Some(exit_code);
+    task_inner.res = None;
+    // here we do not remove the thread since we are still using the kstack
+    // it will be deallocated when sys_waittid is called
+    drop(task_inner);
+    drop(task);
+    // however, if this is the main thread of current process
+    // the process should terminate at once
+    if tid == 0 {
+        let pid = process.getpid();
+        if pid == IDLE_PID {
+            println!(
+                "[kernel] Idle process exit with exit_code {} ...",
+                exit_code
+            );
+            if exit_code != 0 {
+                //crate::sbi::shutdown(255); //255 == -1 for err hint
+                crate::board::QEMU_EXIT_HANDLE.exit_failure();
+            } else {
+                //crate::sbi::shutdown(0); //0 for success hint
+                crate::board::QEMU_EXIT_HANDLE.exit_success();
+            }
+        }
+        remove_from_pid2process(pid);
+        let mut process_inner = process.inner_exclusive_access();
+        // mark this process as a zombie process
+        process_inner.is_zombie = true;
+        // record exit code of main process
+        process_inner.exit_code = exit_code;
+
+        {
+            // move all child processes under init process
+            let mut initproc_inner = INITPROC.inner_exclusive_access();
+            for child in process_inner.children.iter() {
+                child.inner_exclusive_access().parent = Some(Arc::downgrade(&INITPROC));
+                initproc_inner.children.push(child.clone());
+            }
         }
+
+        // deallocate user res (including tid/trap_cx/ustack) of all threads
+        // it has to be done before we dealloc the whole memory_set
+        // otherwise they will be deallocated twice
+        let mut recycle_res = Vec::<TaskUserRes>::new();
+        for task in process_inner.tasks.iter().filter(|t| t.is_some()) {
+            let task = task.as_ref().unwrap();
+            let mut task_inner = task.inner_exclusive_access();
+            if let Some(res) = task_inner.res.take() {
+                recycle_res.push(res);
+            }
+        }
+        // dealloc_tid and dealloc_user_res require access to PCB inner, so we
+        // need to collect those user res first, then release process_inner
+        // for now to avoid deadlock/double borrow problem.
+        drop(process_inner);
+        recycle_res.clear();
+
+        let mut process_inner = process.inner_exclusive_access();
+        process_inner.children.clear();
+        // deallocate other data in user space i.e. program code/data section
+        process_inner.memory_set.recycle_data_pages();
+        // drop file descriptors
+        process_inner.fd_table.clear();
     }
-    // ++++++ release parent PCB
-
-    inner.children.clear();
-    // deallocate user space
-    inner.memory_set.recycle_data_pages();
-    // drop file descriptors
-    inner.fd_table.clear();
-    drop(inner);
-    // **** release current PCB
-    // drop task manually to maintain rc correctly
-    drop(task);
+    drop(process);
     // we do not have to save task context
     let mut _unused = TaskContext::zero_init();
     schedule(&mut _unused as *mut _);
 }
 
 lazy_static! {
-    pub static ref INITPROC: Arc<TaskControlBlock> = Arc::new({
+    pub static ref INITPROC: Arc<ProcessControlBlock> = {
         let inode = open_file("initproc", OpenFlags::RDONLY).unwrap();
         let v = inode.read_all();
-        TaskControlBlock::new(v.as_slice())
-    });
+        ProcessControlBlock::new(v.as_slice())
+    };
 }
 
 pub fn add_initproc() {
-    add_task(INITPROC.clone());
+    let _initproc = INITPROC.clone();
 }
 
-pub fn check_signals_error_of_current() -> Option<(i32, &'static str)> {
-    let task = current_task().unwrap();
-    let task_inner = task.inner_exclusive_access();
-    task_inner.signals.check_error()
+pub fn check_signals_of_current() -> Option<(i32, &'static str)> {
+    let process = current_process();
+    let process_inner = process.inner_exclusive_access();
+    process_inner.signals.check_error()
 }
 
 pub fn current_add_signal(signal: SignalFlags) {
-    let task = current_task().unwrap();
-    let mut task_inner = task.inner_exclusive_access();
-    task_inner.signals |= signal;
-}
-
-fn call_kernel_signal_handler(signal: SignalFlags) {
-    let task = current_task().unwrap();
-    let mut task_inner = task.inner_exclusive_access();
-    match signal {
-        SignalFlags::SIGSTOP => {
-            task_inner.frozen = true;
-            task_inner.signals ^= SignalFlags::SIGSTOP;
-        }
-        SignalFlags::SIGCONT => {
-            if task_inner.signals.contains(SignalFlags::SIGCONT) {
-                task_inner.signals ^= SignalFlags::SIGCONT;
-                task_inner.frozen = false;
-            }
-        }
-        _ => {
-            task_inner.killed = true;
-        }
-    }
-}
-
-fn call_user_signal_handler(sig: usize, signal: SignalFlags) {
-    let task = current_task().unwrap();
-    let mut task_inner = task.inner_exclusive_access();
-
-    let handler = task_inner.signal_actions.table[sig].handler;
-    // change current mask
-    task_inner.signal_mask = task_inner.signal_actions.table[sig].mask;
-    // handle flag
-    task_inner.handling_sig = sig as isize;
-    task_inner.signals ^= signal;
-
-    // backup trapframe
-    let mut trap_ctx = task_inner.get_trap_cx();
-    task_inner.trap_ctx_backup = Some(*trap_ctx);
-    
-    // modify trapframe
-    trap_ctx.sepc = handler;
-
-    // put args (a0)
-    trap_ctx.x[10] = sig;
-}
-
-fn check_pending_signals() {
-    for sig in 0..(MAX_SIG + 1) {
-        let task = current_task().unwrap();
-        let task_inner = task.inner_exclusive_access();
-        let signal = SignalFlags::from_bits(1 << sig).unwrap();
-        if task_inner.signals.contains(signal) && (!task_inner.signal_mask.contains(signal)) {
-            if task_inner.handling_sig == -1 {
-                drop(task_inner);
-                drop(task);
-                if signal == SignalFlags::SIGKILL || signal == SignalFlags::SIGSTOP ||
-                    signal == SignalFlags::SIGCONT || signal == SignalFlags::SIGDEF {
-                        // signal is a kernel signal
-                        call_kernel_signal_handler(signal);
-                } else {
-                    // signal is a user signal
-                    call_user_signal_handler(sig, signal);
-                    return;
-                }
-            } else {
-                if !task_inner.signal_actions.table[task_inner.handling_sig as usize].mask.contains(signal) {
-                    drop(task_inner);
-                    drop(task);
-                    if signal == SignalFlags::SIGKILL || signal == SignalFlags::SIGSTOP ||
-                        signal == SignalFlags::SIGCONT || signal == SignalFlags::SIGDEF {
-                            // signal is a kernel signal
-                            call_kernel_signal_handler(signal);
-                    } else {
-                        // signal is a user signal
-                        call_user_signal_handler(sig, signal);
-                        return;
-                    }
-                }
-            }
-        }
-    }
-}
-
-pub fn handle_signals() {
-    check_pending_signals();
-    loop {
-        let task = current_task().unwrap();
-        let task_inner = task.inner_exclusive_access();
-        let frozen_flag = task_inner.frozen;
-        let killed_flag = task_inner.killed;
-        drop(task_inner);
-        drop(task);
-        if (!frozen_flag) || killed_flag {
-            break;
-        }
-        check_pending_signals();
-        suspend_current_and_run_next()
-    }
+    let process = current_process();
+    let mut process_inner = process.inner_exclusive_access();
+    process_inner.signals |= signal;
 }

os/src/task/pid.rs

@@ -1,104 +0,0 @@
-use crate::config::{KERNEL_STACK_SIZE, PAGE_SIZE, TRAMPOLINE};
-use crate::mm::{MapPermission, VirtAddr, KERNEL_SPACE};
-use crate::sync::UPSafeCell;
-use alloc::vec::Vec;
-use lazy_static::*;
-
-struct PidAllocator {
-    current: usize,
-    recycled: Vec<usize>,
-}
-
-impl PidAllocator {
-    pub fn new() -> Self {
-        PidAllocator {
-            current: 0,
-            recycled: Vec::new(),
-        }
-    }
-    pub fn alloc(&mut self) -> PidHandle {
-        if let Some(pid) = self.recycled.pop() {
-            PidHandle(pid)
-        } else {
-            self.current += 1;
-            PidHandle(self.current - 1)
-        }
-    }
-    pub fn dealloc(&mut self, pid: usize) {
-        assert!(pid < self.current);
-        assert!(
-            !self.recycled.iter().any(|ppid| *ppid == pid),
-            "pid {} has been deallocated!",
-            pid
-        );
-        self.recycled.push(pid);
-    }
-}
-
-lazy_static! {
-    static ref PID_ALLOCATOR: UPSafeCell<PidAllocator> =
-        unsafe { UPSafeCell::new(PidAllocator::new()) };
-}
-
-pub struct PidHandle(pub usize);
-
-impl Drop for PidHandle {
-    fn drop(&mut self) {
-        //println!("drop pid {}", self.0);
-        PID_ALLOCATOR.exclusive_access().dealloc(self.0);
-    }
-}
-
-pub fn pid_alloc() -> PidHandle {
-    PID_ALLOCATOR.exclusive_access().alloc()
-}
-
-/// Return (bottom, top) of a kernel stack in kernel space.
-pub fn kernel_stack_position(app_id: usize) -> (usize, usize) {
-    let top = TRAMPOLINE - app_id * (KERNEL_STACK_SIZE + PAGE_SIZE);
-    let bottom = top - KERNEL_STACK_SIZE;
-    (bottom, top)
-}
-
-pub struct KernelStack {
-    pid: usize,
-}
-
-impl KernelStack {
-    pub fn new(pid_handle: &PidHandle) -> Self {
-        let pid = pid_handle.0;
-        let (kernel_stack_bottom, kernel_stack_top) = kernel_stack_position(pid);
-        KERNEL_SPACE.exclusive_access().insert_framed_area(
-            kernel_stack_bottom.into(),
-            kernel_stack_top.into(),
-            MapPermission::R | MapPermission::W,
-        );
-        KernelStack { pid: pid_handle.0 }
-    }
-    #[allow(unused)]
-    pub fn push_on_top<T>(&self, value: T) -> *mut T
-    where
-        T: Sized,
-    {
-        let kernel_stack_top = self.get_top();
-        let ptr_mut = (kernel_stack_top - core::mem::size_of::<T>()) as *mut T;
-        unsafe {
-            *ptr_mut = value;
-        }
-        ptr_mut
-    }
-    pub fn get_top(&self) -> usize {
-        let (_, kernel_stack_top) = kernel_stack_position(self.pid);
-        kernel_stack_top
-    }
-}
-
-impl Drop for KernelStack {
-    fn drop(&mut self) {
-        let (kernel_stack_bottom, _) = kernel_stack_position(self.pid);
-        let kernel_stack_bottom_va: VirtAddr = kernel_stack_bottom.into();
-        KERNEL_SPACE
-            .exclusive_access()
-            .remove_area_with_start_vpn(kernel_stack_bottom_va.into());
-    }
-}

os/src/task/process.rs

@@ -0,0 +1,258 @@
+use super::id::RecycleAllocator;
+use super::manager::insert_into_pid2process;
+use super::TaskControlBlock;
+use super::{add_task, SignalFlags};
+use super::{pid_alloc, PidHandle};
+use crate::fs::{File, Stdin, Stdout};
+use crate::mm::{translated_refmut, MemorySet, KERNEL_SPACE};
+use crate::sync::{Condvar, Mutex, Semaphore, UPIntrFreeCell, UPIntrRefMut};
+use crate::trap::{trap_handler, TrapContext};
+use alloc::string::String;
+use alloc::sync::{Arc, Weak};
+use alloc::vec;
+use alloc::vec::Vec;
+
+pub struct ProcessControlBlock {
+    // immutable
+    pub pid: PidHandle,
+    // mutable
+    inner: UPIntrFreeCell<ProcessControlBlockInner>,
+}
+
+pub struct ProcessControlBlockInner {
+    pub is_zombie: bool,
+    pub memory_set: MemorySet,
+    pub parent: Option<Weak<ProcessControlBlock>>,
+    pub children: Vec<Arc<ProcessControlBlock>>,
+    pub exit_code: i32,
+    pub fd_table: Vec<Option<Arc<dyn File + Send + Sync>>>,
+    pub signals: SignalFlags,
+    pub tasks: Vec<Option<Arc<TaskControlBlock>>>,
+    pub task_res_allocator: RecycleAllocator,
+    pub mutex_list: Vec<Option<Arc<dyn Mutex>>>,
+    pub semaphore_list: Vec<Option<Arc<Semaphore>>>,
+    pub condvar_list: Vec<Option<Arc<Condvar>>>,
+}
+
+impl ProcessControlBlockInner {
+    #[allow(unused)]
+    pub fn get_user_token(&self) -> usize {
+        self.memory_set.token()
+    }
+
+    pub fn alloc_fd(&mut self) -> usize {
+        if let Some(fd) = (0..self.fd_table.len()).find(|fd| self.fd_table[*fd].is_none()) {
+            fd
+        } else {
+            self.fd_table.push(None);
+            self.fd_table.len() - 1
+        }
+    }
+
+    pub fn alloc_tid(&mut self) -> usize {
+        self.task_res_allocator.alloc()
+    }
+
+    pub fn dealloc_tid(&mut self, tid: usize) {
+        self.task_res_allocator.dealloc(tid)
+    }
+
+    pub fn thread_count(&self) -> usize {
+        self.tasks.len()
+    }
+
+    pub fn get_task(&self, tid: usize) -> Arc<TaskControlBlock> {
+        self.tasks[tid].as_ref().unwrap().clone()
+    }
+}
+
+impl ProcessControlBlock {
+    pub fn inner_exclusive_access(&self) -> UPIntrRefMut<'_, ProcessControlBlockInner> {
+        self.inner.exclusive_access()
+    }
+
+    pub fn new(elf_data: &[u8]) -> Arc<Self> {
+        // memory_set with elf program headers/trampoline/trap context/user stack
+        let (memory_set, ustack_base, entry_point) = MemorySet::from_elf(elf_data);
+        // allocate a pid
+        let pid_handle = pid_alloc();
+        let process = Arc::new(Self {
+            pid: pid_handle,
+            inner: unsafe {
+                UPIntrFreeCell::new(ProcessControlBlockInner {
+                    is_zombie: false,
+                    memory_set,
+                    parent: None,
+                    children: Vec::new(),
+                    exit_code: 0,
+                    fd_table: vec![
+                        // 0 -> stdin
+                        Some(Arc::new(Stdin)),
+                        // 1 -> stdout
+                        Some(Arc::new(Stdout)),
+                        // 2 -> stderr
+                        Some(Arc::new(Stdout)),
+                    ],
+                    signals: SignalFlags::empty(),
+                    tasks: Vec::new(),
+                    task_res_allocator: RecycleAllocator::new(),
+                    mutex_list: Vec::new(),
+                    semaphore_list: Vec::new(),
+                    condvar_list: Vec::new(),
+                })
+            },
+        });
+        // create a main thread, we should allocate ustack and trap_cx here
+        let task = Arc::new(TaskControlBlock::new(
+            Arc::clone(&process),
+            ustack_base,
+            true,
+        ));
+        // prepare trap_cx of main thread
+        let task_inner = task.inner_exclusive_access();
+        let trap_cx = task_inner.get_trap_cx();
+        let ustack_top = task_inner.res.as_ref().unwrap().ustack_top();
+        let kstack_top = task.kstack.get_top();
+        drop(task_inner);
+        *trap_cx = TrapContext::app_init_context(
+            entry_point,
+            ustack_top,
+            KERNEL_SPACE.exclusive_access().token(),
+            kstack_top,
+            trap_handler as usize,
+        );
+        // add main thread to the process
+        let mut process_inner = process.inner_exclusive_access();
+        process_inner.tasks.push(Some(Arc::clone(&task)));
+        drop(process_inner);
+        insert_into_pid2process(process.getpid(), Arc::clone(&process));
+        // add main thread to scheduler
+        add_task(task);
+        process
+    }
+
+    /// Only support processes with a single thread.
+    pub fn exec(self: &Arc<Self>, elf_data: &[u8], args: Vec<String>) {
+        assert_eq!(self.inner_exclusive_access().thread_count(), 1);
+        // memory_set with elf program headers/trampoline/trap context/user stack
+        let (memory_set, ustack_base, entry_point) = MemorySet::from_elf(elf_data);
+        let new_token = memory_set.token();
+        // substitute memory_set
+        self.inner_exclusive_access().memory_set = memory_set;
+        // then we alloc user resource for main thread again
+        // since memory_set has been changed
+        let task = self.inner_exclusive_access().get_task(0);
+        let mut task_inner = task.inner_exclusive_access();
+        task_inner.res.as_mut().unwrap().ustack_base = ustack_base;
+        task_inner.res.as_mut().unwrap().alloc_user_res();
+        task_inner.trap_cx_ppn = task_inner.res.as_mut().unwrap().trap_cx_ppn();
+        // push arguments on user stack
+        let mut user_sp = task_inner.res.as_mut().unwrap().ustack_top();
+        user_sp -= (args.len() + 1) * core::mem::size_of::<usize>();
+        let argv_base = user_sp;
+        let mut argv: Vec<_> = (0..=args.len())
+            .map(|arg| {
+                translated_refmut(
+                    new_token,
+                    (argv_base + arg * core::mem::size_of::<usize>()) as *mut usize,
+                )
+            })
+            .collect();
+        *argv[args.len()] = 0;
+        for i in 0..args.len() {
+            user_sp -= args[i].len() + 1;
+            *argv[i] = user_sp;
+            let mut p = user_sp;
+            for c in args[i].as_bytes() {
+                *translated_refmut(new_token, p as *mut u8) = *c;
+                p += 1;
+            }
+            *translated_refmut(new_token, p as *mut u8) = 0;
+        }
+        // make the user_sp aligned to 8B for k210 platform
+        user_sp -= user_sp % core::mem::size_of::<usize>();
+        // initialize trap_cx
+        let mut trap_cx = TrapContext::app_init_context(
+            entry_point,
+            user_sp,
+            KERNEL_SPACE.exclusive_access().token(),
+            task.kstack.get_top(),
+            trap_handler as usize,
+        );
+        trap_cx.x[10] = args.len();
+        trap_cx.x[11] = argv_base;
+        *task_inner.get_trap_cx() = trap_cx;
+    }
+
+    /// Only support processes with a single thread.
+    pub fn fork(self: &Arc<Self>) -> Arc<Self> {
+        let mut parent = self.inner_exclusive_access();
+        assert_eq!(parent.thread_count(), 1);
+        // clone parent's memory_set completely including trampoline/ustacks/trap_cxs
+        let memory_set = MemorySet::from_existed_user(&parent.memory_set);
+        // alloc a pid
+        let pid = pid_alloc();
+        // copy fd table
+        let mut new_fd_table: Vec<Option<Arc<dyn File + Send + Sync>>> = Vec::new();
+        for fd in parent.fd_table.iter() {
+            if let Some(file) = fd {
+                new_fd_table.push(Some(file.clone()));
+            } else {
+                new_fd_table.push(None);
+            }
+        }
+        // create child process pcb
+        let child = Arc::new(Self {
+            pid,
+            inner: unsafe {
+                UPIntrFreeCell::new(ProcessControlBlockInner {
+                    is_zombie: false,
+                    memory_set,
+                    parent: Some(Arc::downgrade(self)),
+                    children: Vec::new(),
+                    exit_code: 0,
+                    fd_table: new_fd_table,
+                    signals: SignalFlags::empty(),
+                    tasks: Vec::new(),
+                    task_res_allocator: RecycleAllocator::new(),
+                    mutex_list: Vec::new(),
+                    semaphore_list: Vec::new(),
+                    condvar_list: Vec::new(),
+                })
+            },
+        });
+        // add child
+        parent.children.push(Arc::clone(&child));
+        // create main thread of child process
+        let task = Arc::new(TaskControlBlock::new(
+            Arc::clone(&child),
+            parent
+                .get_task(0)
+                .inner_exclusive_access()
+                .res
+                .as_ref()
+                .unwrap()
+                .ustack_base(),
+            // here we do not allocate trap_cx or ustack again
+            // but mention that we allocate a new kstack here
+            false,
+        ));
+        // attach task to child process
+        let mut child_inner = child.inner_exclusive_access();
+        child_inner.tasks.push(Some(Arc::clone(&task)));
+        drop(child_inner);
+        // modify kstack_top in trap_cx of this thread
+        let task_inner = task.inner_exclusive_access();
+        let trap_cx = task_inner.get_trap_cx();
+        trap_cx.kernel_sp = task.kstack.get_top();
+        drop(task_inner);
+        insert_into_pid2process(child.getpid(), Arc::clone(&child));
+        // add this thread to scheduler
+        add_task(task);
+        child
+    }
+
+    pub fn getpid(&self) -> usize {
+        self.pid.0
+    }
+}

os/src/task/processor.rs

@@ -1,7 +1,7 @@
 use super::__switch;
 use super::{fetch_task, TaskStatus};
-use super::{TaskContext, TaskControlBlock};
-use crate::sync::UPSafeCell;
+use super::{ProcessControlBlock, TaskContext, TaskControlBlock};
+use crate::sync::UPIntrFreeCell;
 use crate::trap::TrapContext;
 use alloc::sync::Arc;
 use lazy_static::*;
@@ -30,7 +30,8 @@ impl Processor {
 }
 
 lazy_static! {
-    pub static ref PROCESSOR: UPSafeCell<Processor> = unsafe { UPSafeCell::new(Processor::new()) };
+    pub static ref PROCESSOR: UPIntrFreeCell<Processor> =
+        unsafe { UPIntrFreeCell::new(Processor::new()) };
 }
 
 pub fn run_tasks() {
@@ -39,17 +40,18 @@ pub fn run_tasks() {
         if let Some(task) = fetch_task() {
             let idle_task_cx_ptr = processor.get_idle_task_cx_ptr();
             // access coming task TCB exclusively
-            let mut task_inner = task.inner_exclusive_access();
-            let next_task_cx_ptr = &task_inner.task_cx as *const TaskContext;
-            task_inner.task_status = TaskStatus::Running;
-            drop(task_inner);
-            // release coming task TCB manually
+            let next_task_cx_ptr = task.inner.exclusive_session(|task_inner| {
+                task_inner.task_status = TaskStatus::Running;
+                &task_inner.task_cx as *const TaskContext
+            });
             processor.current = Some(task);
             // release processor manually
             drop(processor);
             unsafe {
                 __switch(idle_task_cx_ptr, next_task_cx_ptr);
             }
+        } else {
+            println!("no tasks available in run_tasks");
         }
     }
 }
@@ -62,10 +64,13 @@ pub fn current_task() -> Option<Arc<TaskControlBlock>> {
     PROCESSOR.exclusive_access().current()
 }
 
+pub fn current_process() -> Arc<ProcessControlBlock> {
+    current_task().unwrap().process.upgrade().unwrap()
+}
+
 pub fn current_user_token() -> usize {
     let task = current_task().unwrap();
-    let token = task.inner_exclusive_access().get_user_token();
-    token
+    task.get_user_token()
 }
 
 pub fn current_trap_cx() -> &'static mut TrapContext {
@@ -75,10 +80,23 @@ pub fn current_trap_cx() -> &'static mut TrapContext {
         .get_trap_cx()
 }
 
+pub fn current_trap_cx_user_va() -> usize {
+    current_task()
+        .unwrap()
+        .inner_exclusive_access()
+        .res
+        .as_ref()
+        .unwrap()
+        .trap_cx_user_va()
+}
+
+pub fn current_kstack_top() -> usize {
+    current_task().unwrap().kstack.get_top()
+}
+
 pub fn schedule(switched_task_cx_ptr: *mut TaskContext) {
-    let mut processor = PROCESSOR.exclusive_access();
-    let idle_task_cx_ptr = processor.get_idle_task_cx_ptr();
-    drop(processor);
+    let idle_task_cx_ptr =
+        PROCESSOR.exclusive_session(|processor| processor.get_idle_task_cx_ptr());
     unsafe {
         __switch(switched_task_cx_ptr, idle_task_cx_ptr);
     }

os/src/task/signal.rs

@@ -1,41 +1,12 @@
 use bitflags::*;
 
-pub const MAX_SIG: usize = 31;
-
 bitflags! {
     pub struct SignalFlags: u32 {
-        const SIGDEF = 1; // Default signal handling
-        const SIGHUP = 1 << 1;
-        const SIGINT = 1 << 2;
-        const SIGQUIT = 1 << 3;
-        const SIGILL = 1 << 4;
-        const SIGTRAP = 1 << 5;
-        const SIGABRT = 1 << 6;
-        const SIGBUS = 1 << 7;
-        const SIGFPE = 1 << 8;
-        const SIGKILL = 1 << 9;
-        const SIGUSR1 = 1 << 10;
-        const SIGSEGV = 1 << 11;
-        const SIGUSR2 = 1 << 12;
-        const SIGPIPE = 1 << 13;
-        const SIGALRM = 1 << 14;
-        const SIGTERM = 1 << 15;
-        const SIGSTKFLT = 1 << 16;
-        const SIGCHLD = 1 << 17;
-        const SIGCONT = 1 << 18;
-        const SIGSTOP = 1 << 19;
-        const SIGTSTP = 1 << 20;
-        const SIGTTIN = 1 << 21;
-        const SIGTTOU = 1 << 22;
-        const SIGURG = 1 << 23;
-        const SIGXCPU = 1 << 24;
-        const SIGXFSZ = 1 << 25;
-        const SIGVTALRM = 1 << 26;
-        const SIGPROF = 1 << 27;
-        const SIGWINCH = 1 << 28;
-        const SIGIO = 1 << 29;
-        const SIGPWR = 1 << 30;
-        const SIGSYS = 1 << 31;
+        const SIGINT    = 1 << 2;
+        const SIGILL    = 1 << 4;
+        const SIGABRT   = 1 << 6;
+        const SIGFPE    = 1 << 8;
+        const SIGSEGV   = 1 << 11;
     }
 }
 
@@ -49,8 +20,6 @@ impl SignalFlags {
             Some((-6, "Aborted, SIGABRT=6"))
         } else if self.contains(Self::SIGFPE) {
             Some((-8, "Erroneous Arithmetic Operation, SIGFPE=8"))
-        } else if self.contains(Self::SIGKILL) {
-            Some((-9, "Killed, SIGKILL=9"))
         } else if self.contains(Self::SIGSEGV) {
             Some((-11, "Segmentation Fault, SIGSEGV=11"))
         } else {

os/src/task/task.rs

@@ -1,238 +1,74 @@
-use super::{TaskContext, SignalActions};
-use super::{pid_alloc, KernelStack, PidHandle, SignalFlags};
-use crate::config::TRAP_CONTEXT;
-use crate::fs::{File, Stdin, Stdout};
-use crate::mm::{translated_refmut, MemorySet, PhysPageNum, VirtAddr, KERNEL_SPACE};
-use crate::sync::UPSafeCell;
-use crate::trap::{trap_handler, TrapContext};
-use alloc::string::String;
+use super::id::TaskUserRes;
+use super::{kstack_alloc, KernelStack, ProcessControlBlock, TaskContext};
+use crate::trap::TrapContext;
+use crate::{
+    mm::PhysPageNum,
+    sync::{UPIntrFreeCell, UPIntrRefMut},
+};
 use alloc::sync::{Arc, Weak};
-use alloc::vec;
-use alloc::vec::Vec;
-use core::cell::RefMut;
 
 pub struct TaskControlBlock {
     // immutable
-    pub pid: PidHandle,
-    pub kernel_stack: KernelStack,
+    pub process: Weak<ProcessControlBlock>,
+    pub kstack: KernelStack,
     // mutable
-    inner: UPSafeCell<TaskControlBlockInner>,
+    pub inner: UPIntrFreeCell<TaskControlBlockInner>,
+}
+
+impl TaskControlBlock {
+    pub fn inner_exclusive_access(&self) -> UPIntrRefMut<'_, TaskControlBlockInner> {
+        self.inner.exclusive_access()
+    }
+
+    pub fn get_user_token(&self) -> usize {
+        let process = self.process.upgrade().unwrap();
+        let inner = process.inner_exclusive_access();
+        inner.memory_set.token()
+    }
 }
 
 pub struct TaskControlBlockInner {
+    pub res: Option<TaskUserRes>,
     pub trap_cx_ppn: PhysPageNum,
-    pub base_size: usize,
     pub task_cx: TaskContext,
     pub task_status: TaskStatus,
-    pub memory_set: MemorySet,
-    pub parent: Option<Weak<TaskControlBlock>>,
-    pub children: Vec<Arc<TaskControlBlock>>,
-    pub exit_code: i32,
-    pub fd_table: Vec<Option<Arc<dyn File + Send + Sync>>>,
-    pub signals: SignalFlags,
-    pub signal_mask: SignalFlags,
-    // the signal which is being handling
-    pub handling_sig: isize,
-    // Signal actions
-    pub signal_actions: SignalActions,
-    // if the task is killed
-    pub killed: bool,
-    // if the task is frozen by a signal
-    pub frozen: bool,
-    pub trap_ctx_backup: Option<TrapContext>
+    pub exit_code: Option<i32>,
 }
 
 impl TaskControlBlockInner {
     pub fn get_trap_cx(&self) -> &'static mut TrapContext {
         self.trap_cx_ppn.get_mut()
     }
-    pub fn get_user_token(&self) -> usize {
-        self.memory_set.token()
-    }
+
+    #[allow(unused)]
     fn get_status(&self) -> TaskStatus {
         self.task_status
     }
-    pub fn is_zombie(&self) -> bool {
-        self.get_status() == TaskStatus::Zombie
-    }
-    pub fn alloc_fd(&mut self) -> usize {
-        if let Some(fd) = (0..self.fd_table.len()).find(|fd| self.fd_table[*fd].is_none()) {
-            fd
-        } else {
-            self.fd_table.push(None);
-            self.fd_table.len() - 1
-        }
-    }
 }
 
 impl TaskControlBlock {
-    pub fn inner_exclusive_access(&self) -> RefMut<'_, TaskControlBlockInner> {
-        self.inner.exclusive_access()
-    }
-    pub fn new(elf_data: &[u8]) -> Self {
-        // memory_set with elf program headers/trampoline/trap context/user stack
-        let (memory_set, user_sp, entry_point) = MemorySet::from_elf(elf_data);
-        let trap_cx_ppn = memory_set
-            .translate(VirtAddr::from(TRAP_CONTEXT).into())
-            .unwrap()
-            .ppn();
-        // alloc a pid and a kernel stack in kernel space
-        let pid_handle = pid_alloc();
-        let kernel_stack = KernelStack::new(&pid_handle);
-        let kernel_stack_top = kernel_stack.get_top();
-        let task_control_block = Self {
-            pid: pid_handle,
-            kernel_stack,
+    pub fn new(
+        process: Arc<ProcessControlBlock>,
+        ustack_base: usize,
+        alloc_user_res: bool,
+    ) -> Self {
+        let res = TaskUserRes::new(Arc::clone(&process), ustack_base, alloc_user_res);
+        let trap_cx_ppn = res.trap_cx_ppn();
+        let kstack = kstack_alloc();
+        let kstack_top = kstack.get_top();
+        Self {
+            process: Arc::downgrade(&process),
+            kstack,
             inner: unsafe {
-                UPSafeCell::new(TaskControlBlockInner {
+                UPIntrFreeCell::new(TaskControlBlockInner {
+                    res: Some(res),
                     trap_cx_ppn,
-                    base_size: user_sp,
-                    task_cx: TaskContext::goto_trap_return(kernel_stack_top),
+                    task_cx: TaskContext::goto_trap_return(kstack_top),
                     task_status: TaskStatus::Ready,
-                    memory_set,
-                    parent: None,
-                    children: Vec::new(),
-                    exit_code: 0,
-                    fd_table: vec![
-                        // 0 -> stdin
-                        Some(Arc::new(Stdin)),
-                        // 1 -> stdout
-                        Some(Arc::new(Stdout)),
-                        // 2 -> stderr
-                        Some(Arc::new(Stdout)),
-                    ],
-                    signals: SignalFlags::empty(),
-                    signal_mask: SignalFlags::empty(),
-                    handling_sig: -1,
-                    signal_actions: SignalActions::default(),
-                    killed: false,
-                    frozen: false,
-                    trap_ctx_backup: None
+                    exit_code: None,
                 })
             },
-        };
-        // prepare TrapContext in user space
-        let trap_cx = task_control_block.inner_exclusive_access().get_trap_cx();
-        *trap_cx = TrapContext::app_init_context(
-            entry_point,
-            user_sp,
-            KERNEL_SPACE.exclusive_access().token(),
-            kernel_stack_top,
-            trap_handler as usize,
-        );
-        task_control_block
-    }
-    pub fn exec(&self, elf_data: &[u8], args: Vec<String>) {
-        // memory_set with elf program headers/trampoline/trap context/user stack
-        let (memory_set, mut user_sp, entry_point) = MemorySet::from_elf(elf_data);
-        let trap_cx_ppn = memory_set
-            .translate(VirtAddr::from(TRAP_CONTEXT).into())
-            .unwrap()
-            .ppn();
-        // push arguments on user stack
-        user_sp -= (args.len() + 1) * core::mem::size_of::<usize>();
-        let argv_base = user_sp;
-        let mut argv: Vec<_> = (0..=args.len())
-            .map(|arg| {
-                translated_refmut(
-                    memory_set.token(),
-                    (argv_base + arg * core::mem::size_of::<usize>()) as *mut usize,
-                )
-            })
-            .collect();
-        *argv[args.len()] = 0;
-        for i in 0..args.len() {
-            user_sp -= args[i].len() + 1;
-            *argv[i] = user_sp;
-            let mut p = user_sp;
-            for c in args[i].as_bytes() {
-                *translated_refmut(memory_set.token(), p as *mut u8) = *c;
-                p += 1;
-            }
-            *translated_refmut(memory_set.token(), p as *mut u8) = 0;
-        }
-        // make the user_sp aligned to 8B for k210 platform
-        user_sp -= user_sp % core::mem::size_of::<usize>();
-
-        // **** access current TCB exclusively
-        let mut inner = self.inner_exclusive_access();
-        // substitute memory_set
-        inner.memory_set = memory_set;
-        // update trap_cx ppn
-        inner.trap_cx_ppn = trap_cx_ppn;
-        // initialize trap_cx
-        let mut trap_cx = TrapContext::app_init_context(
-            entry_point,
-            user_sp,
-            KERNEL_SPACE.exclusive_access().token(),
-            self.kernel_stack.get_top(),
-            trap_handler as usize,
-        );
-        trap_cx.x[10] = args.len();
-        trap_cx.x[11] = argv_base;
-        *inner.get_trap_cx() = trap_cx;
-        // **** release current PCB
-    }
-    pub fn fork(self: &Arc<TaskControlBlock>) -> Arc<TaskControlBlock> {
-        // ---- hold parent PCB lock
-        let mut parent_inner = self.inner_exclusive_access();
-        // copy user space(include trap context)
-        let memory_set = MemorySet::from_existed_user(&parent_inner.memory_set);
-        let trap_cx_ppn = memory_set
-            .translate(VirtAddr::from(TRAP_CONTEXT).into())
-            .unwrap()
-            .ppn();
-        // alloc a pid and a kernel stack in kernel space
-        let pid_handle = pid_alloc();
-        let kernel_stack = KernelStack::new(&pid_handle);
-        let kernel_stack_top = kernel_stack.get_top();
-        // copy fd table
-        let mut new_fd_table: Vec<Option<Arc<dyn File + Send + Sync>>> = Vec::new();
-        for fd in parent_inner.fd_table.iter() {
-            if let Some(file) = fd {
-                new_fd_table.push(Some(file.clone()));
-            } else {
-                new_fd_table.push(None);
-            }
         }
-        let task_control_block = Arc::new(TaskControlBlock {
-            pid: pid_handle,
-            kernel_stack,
-            inner: unsafe {
-                UPSafeCell::new(TaskControlBlockInner {
-                    trap_cx_ppn,
-                    base_size: parent_inner.base_size,
-                    task_cx: TaskContext::goto_trap_return(kernel_stack_top),
-                    task_status: TaskStatus::Ready,
-                    memory_set,
-                    parent: Some(Arc::downgrade(self)),
-                    children: Vec::new(),
-                    exit_code: 0,
-                    fd_table: new_fd_table,
-                    signals: SignalFlags::empty(),
-                    // inherit the signal_mask and signal_action
-                    signal_mask: parent_inner.signal_mask,
-                    handling_sig: -1,
-                    signal_actions: parent_inner.signal_actions.clone(),
-                    killed: false,
-                    frozen: false,
-                    trap_ctx_backup: None
-                })
-            },
-        });
-        // add child
-        parent_inner.children.push(task_control_block.clone());
-        // modify kernel_sp in trap_cx
-        // **** access child PCB exclusively
-        let trap_cx = task_control_block.inner_exclusive_access().get_trap_cx();
-        trap_cx.kernel_sp = kernel_stack_top;
-        // return
-        task_control_block
-        // **** release child PCB
-        // ---- release parent PCB
-    }
-    pub fn getpid(&self) -> usize {
-        self.pid.0
     }
 }
 
@@ -240,5 +76,5 @@ impl TaskControlBlock {
 pub enum TaskStatus {
     Ready,
     Running,
-    Zombie,
+    Blocking,
 }

os/src/timer.rs

@@ -1,5 +1,12 @@
+use core::cmp::Ordering;
+
 use crate::config::CLOCK_FREQ;
 use crate::sbi::set_timer;
+use crate::sync::UPIntrFreeCell;
+use crate::task::{add_task, TaskControlBlock};
+use alloc::collections::BinaryHeap;
+use alloc::sync::Arc;
+use lazy_static::*;
 use riscv::register::time;
 
 const TICKS_PER_SEC: usize = 100;
@@ -16,3 +23,51 @@ pub fn get_time_ms() -> usize {
 pub fn set_next_trigger() {
     set_timer(get_time() + CLOCK_FREQ / TICKS_PER_SEC);
 }
+
+pub struct TimerCondVar {
+    pub expire_ms: usize,
+    pub task: Arc<TaskControlBlock>,
+}
+
+impl PartialEq for TimerCondVar {
+    fn eq(&self, other: &Self) -> bool {
+        self.expire_ms == other.expire_ms
+    }
+}
+impl Eq for TimerCondVar {}
+impl PartialOrd for TimerCondVar {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        let a = -(self.expire_ms as isize);
+        let b = -(other.expire_ms as isize);
+        Some(a.cmp(&b))
+    }
+}
+
+impl Ord for TimerCondVar {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.partial_cmp(other).unwrap()
+    }
+}
+
+lazy_static! {
+    static ref TIMERS: UPIntrFreeCell<BinaryHeap<TimerCondVar>> =
+        unsafe { UPIntrFreeCell::new(BinaryHeap::<TimerCondVar>::new()) };
+}
+
+pub fn add_timer(expire_ms: usize, task: Arc<TaskControlBlock>) {
+    let mut timers = TIMERS.exclusive_access();
+    timers.push(TimerCondVar { expire_ms, task });
+}
+
+pub fn check_timer() {
+    let current_ms = get_time_ms();
+    let mut timers = TIMERS.exclusive_access();
+    while let Some(timer) = timers.peek() {
+        if timer.expire_ms <= current_ms {
+            add_task(Arc::clone(&timer.task));
+            timers.pop();
+        } else {
+            break;
+        }
+    }
+}

os/src/trap/context.rs

@@ -1,7 +1,7 @@
 use riscv::register::sstatus::{self, Sstatus, SPP};
 
 #[repr(C)]
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug)]
 pub struct TrapContext {
     pub x: [usize; 32],
     pub sstatus: Sstatus,

os/src/trap/mod.rs

@@ -1,17 +1,17 @@
 mod context;
 
-use crate::config::{TRAMPOLINE, TRAP_CONTEXT};
+use crate::config::TRAMPOLINE;
 use crate::syscall::syscall;
 use crate::task::{
-    check_signals_error_of_current, current_add_signal, current_trap_cx, current_user_token,
-    exit_current_and_run_next, suspend_current_and_run_next, SignalFlags, handle_signals,
+    check_signals_of_current, current_add_signal, current_trap_cx, current_trap_cx_user_va,
+    current_user_token, exit_current_and_run_next, suspend_current_and_run_next, SignalFlags,
 };
-use crate::timer::set_next_trigger;
+use crate::timer::{check_timer, set_next_trigger};
 use core::arch::{asm, global_asm};
 use riscv::register::{
     mtvec::TrapMode,
     scause::{self, Exception, Interrupt, Trap},
-    sie, stval, stvec,
+    sie, sscratch, sstatus, stval, stvec,
 };
 
 global_asm!(include_str!("trap.S"));
@@ -21,8 +21,14 @@ pub fn init() {
 }
 
 fn set_kernel_trap_entry() {
+    extern "C" {
+        fn __alltraps();
+        fn __alltraps_k();
+    }
+    let __alltraps_k_va = __alltraps_k as usize - __alltraps as usize + TRAMPOLINE;
     unsafe {
-        stvec::write(trap_from_kernel as usize, TrapMode::Direct);
+        stvec::write(__alltraps_k_va, TrapMode::Direct);
+        sscratch::write(trap_from_kernel as usize);
     }
 }
 
@@ -38,16 +44,32 @@ pub fn enable_timer_interrupt() {
     }
 }
 
+fn enable_supervisor_interrupt() {
+    unsafe {
+        sstatus::set_sie();
+    }
+}
+
+fn disable_supervisor_interrupt() {
+    unsafe {
+        sstatus::clear_sie();
+    }
+}
+
 #[no_mangle]
 pub fn trap_handler() -> ! {
     set_kernel_trap_entry();
     let scause = scause::read();
     let stval = stval::read();
+    //println!("into {:?}", scause.cause());
     match scause.cause() {
         Trap::Exception(Exception::UserEnvCall) => {
             // jump to next instruction anyway
             let mut cx = current_trap_cx();
             cx.sepc += 4;
+
+            enable_supervisor_interrupt();
+
             // get system call return value
             let result = syscall(cx.x[17], [cx.x[10], cx.x[11], cx.x[12]]);
             // cx is changed during sys_exec, so we have to call it again
@@ -75,8 +97,12 @@ pub fn trap_handler() -> ! {
         }
         Trap::Interrupt(Interrupt::SupervisorTimer) => {
             set_next_trigger();
+            check_timer();
             suspend_current_and_run_next();
         }
+        Trap::Interrupt(Interrupt::SupervisorExternal) => {
+            crate::board::irq_handler();
+        }
         _ => {
             panic!(
                 "Unsupported trap {:?}, stval = {:#x}!",
@@ -85,11 +111,8 @@ pub fn trap_handler() -> ! {
             );
         }
     }
-    // handle signals (handle the sent signal)
-    handle_signals();
-
-    // check error signals (if error then exit)
-    if let Some((errno, msg)) = check_signals_error_of_current() {
+    // check signals
+    if let Some((errno, msg)) = check_signals_of_current() {
         println!("[kernel] {}", msg);
         exit_current_and_run_next(errno);
     }
@@ -98,20 +121,22 @@ pub fn trap_handler() -> ! {
 
 #[no_mangle]
 pub fn trap_return() -> ! {
+    disable_supervisor_interrupt();
     set_user_trap_entry();
-    let trap_cx_ptr = TRAP_CONTEXT;
+    let trap_cx_user_va = current_trap_cx_user_va();
     let user_satp = current_user_token();
     extern "C" {
         fn __alltraps();
         fn __restore();
     }
     let restore_va = __restore as usize - __alltraps as usize + TRAMPOLINE;
+    //println!("before return");
     unsafe {
         asm!(
             "fence.i",
             "jr {restore_va}",
             restore_va = in(reg) restore_va,
-            in("a0") trap_cx_ptr,
+            in("a0") trap_cx_user_va,
             in("a1") user_satp,
             options(noreturn)
         );
@@ -119,10 +144,26 @@ pub fn trap_return() -> ! {
 }
 
 #[no_mangle]
-pub fn trap_from_kernel() -> ! {
-    use riscv::register::sepc;
-    println!("stval = {:#x}, sepc = {:#x}", stval::read(), sepc::read());
-    panic!("a trap {:?} from kernel!", scause::read().cause());
+pub fn trap_from_kernel(_trap_cx: &TrapContext) {
+    let scause = scause::read();
+    let stval = stval::read();
+    match scause.cause() {
+        Trap::Interrupt(Interrupt::SupervisorExternal) => {
+            crate::board::irq_handler();
+        }
+        Trap::Interrupt(Interrupt::SupervisorTimer) => {
+            set_next_trigger();
+            check_timer();
+            // do not schedule now
+        }
+        _ => {
+            panic!(
+                "Unsupported trap from kernel: {:?}, stval = {:#x}!",
+                scause.cause(),
+                stval
+            );
+        }
+    }
 }
 
 pub use context::TrapContext;

os/src/trap/trap.S

@@ -8,6 +8,8 @@
     .section .text.trampoline
     .globl __alltraps
     .globl __restore
+    .globl __alltraps_k
+    .globl __restore_k
     .align 2
 __alltraps:
     csrrw sp, sscratch, sp
@@ -67,3 +69,36 @@ __restore:
     # back to user stack
     ld sp, 2*8(sp)
     sret
+
+    .align 2
+__alltraps_k:
+    addi sp, sp, -34*8 
+    sd x1, 1*8(sp)
+    sd x3, 3*8(sp)
+    .set n, 5
+    .rept 27
+        SAVE_GP %n
+        .set n, n+1
+    .endr
+    csrr t0, sstatus
+    csrr t1, sepc
+    sd t0, 32*8(sp)
+    sd t1, 33*8(sp)
+    mv a0, sp
+    csrr t2, sscratch
+    jalr t2
+
+__restore_k:
+    ld t0, 32*8(sp)
+    ld t1, 33*8(sp)
+    csrw sstatus, t0
+    csrw sepc, t1
+    ld x1, 1*8(sp)
+    ld x3, 3*8(sp)
+    .set n, 5
+    .rept 27
+        LOAD_GP %n
+        .set n, n+1
+    .endr
+    addi sp, sp, 34*8
+    sret

setenv.sh

@@ -0,0 +1,2 @@
+export PATH=$(rustc --print sysroot)/bin:$PATH
+export RUST_SRC_PATH=$(rustc --print sysroot)/lib/rustlib/src/rust/library/

user/Makefile

@@ -8,9 +8,15 @@ BINS := $(patsubst $(APP_DIR)/%.rs, $(TARGET_DIR)/%.bin, $(APPS))
 
 OBJDUMP := rust-objdump --arch-name=riscv64
 OBJCOPY := rust-objcopy --binary-architecture=riscv64
+CP := cp 
+
+TEST ?= 
 
 elf: $(APPS)
 	@cargo build --release
+ifeq ($(TEST), 1)
+	@$(CP) $(TARGET_DIR)/usertests $(TARGET_DIR)/initproc
+endif
 
 binary: elf
 	$(foreach elf, $(ELFS), $(OBJCOPY) $(elf) --strip-all -O binary $(patsubst $(TARGET_DIR)/%, $(TARGET_DIR)/%.bin, $(elf));)

user/src/bin/cat.rs

@@ -9,10 +9,14 @@ use user_lib::{close, open, read, OpenFlags};
 
 #[no_mangle]
 pub fn main(argc: usize, argv: &[&str]) -> i32 {
+    println!("argc = {}", argc);
+    for (i, arg) in argv.iter().enumerate() {
+        println!("argv[{}] = {}", i, arg);
+    }
     assert!(argc == 2);
     let fd = open(argv[1], OpenFlags::RDONLY);
     if fd == -1 {
-        panic!("Error occured when opening file");
+        panic!("Error occurred when opening file");
     }
     let fd = fd as usize;
     let mut buf = [0u8; 256];

user/src/bin/eisenberg.rs

@@ -0,0 +1,138 @@
+#![no_std]
+#![no_main]
+#![feature(core_intrinsics)]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+extern crate core;
+
+use alloc::vec::Vec;
+use core::sync::atomic::{AtomicUsize, Ordering};
+use user_lib::{exit, sleep, thread_create, waittid};
+
+const N: usize = 2;
+const THREAD_NUM: usize = 10;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum FlagState {
+    Out,
+    Want,
+    In,
+}
+
+static mut TURN: usize = 0;
+static mut FLAG: [FlagState; THREAD_NUM] = [FlagState::Out; THREAD_NUM];
+
+static GUARD: AtomicUsize = AtomicUsize::new(0);
+
+fn critical_test_enter() {
+    assert_eq!(GUARD.fetch_add(1, Ordering::SeqCst), 0);
+}
+
+fn critical_test_claim() {
+    assert_eq!(GUARD.load(Ordering::SeqCst), 1);
+}
+
+fn critical_test_exit() {
+    assert_eq!(GUARD.fetch_sub(1, Ordering::SeqCst), 1);
+}
+
+fn eisenberg_enter_critical(id: usize) {
+    /* announce that we want to enter */
+    loop {
+        println!("Thread[{}] try enter", id);
+        vstore!(&FLAG[id], FlagState::Want);
+        loop {
+            /* check if any with higher priority is `Want` or `In` */
+            let mut prior_thread: Option<usize> = None;
+            let turn = vload!(&TURN);
+            let ring_id = if id < turn { id + THREAD_NUM } else { id };
+            // FLAG.iter() may lead to some errors, use for-loop instead
+            for i in turn..ring_id {
+                if vload!(&FLAG[i % THREAD_NUM]) != FlagState::Out {
+                    prior_thread = Some(i % THREAD_NUM);
+                    break;
+                }
+            }
+            if prior_thread.is_none() {
+                break;
+            }
+            println!(
+                "Thread[{}]: prior thread {} exist, sleep and retry",
+                id,
+                prior_thread.unwrap()
+            );
+            sleep(1);
+        }
+        /* now tentatively claim the resource */
+        vstore!(&FLAG[id], FlagState::In);
+        /* enforce the order of `claim` and `conflict check`*/
+        memory_fence!();
+        /* check if anthor thread is also `In`, which imply a conflict*/
+        let mut conflict = false;
+        for i in 0..THREAD_NUM {
+            if i != id && vload!(&FLAG[i]) == FlagState::In {
+                conflict = true;
+            }
+        }
+        if !conflict {
+            break;
+        }
+        println!("Thread[{}]: CONFLECT!", id);
+        /* no need to sleep */
+    }
+    /* clain the trun */
+    vstore!(&TURN, id);
+    println!("Thread[{}] enter", id);
+}
+
+fn eisenberg_exit_critical(id: usize) {
+    /* find next one who wants to enter and give the turn to it*/
+    let mut next = id;
+    let ring_id = id + THREAD_NUM;
+    for i in (id + 1)..ring_id {
+        let idx = i % THREAD_NUM;
+        if vload!(&FLAG[idx]) == FlagState::Want {
+            next = idx;
+            break;
+        }
+    }
+    vstore!(&TURN, next);
+    /* All done */
+    vstore!(&FLAG[id], FlagState::Out);
+    println!("Thread[{}] exit, give turn to {}", id, next);
+}
+
+pub fn thread_fn(id: usize) -> ! {
+    println!("Thread[{}] init.", id);
+    for _ in 0..N {
+        eisenberg_enter_critical(id);
+        critical_test_enter();
+        for _ in 0..3 {
+            critical_test_claim();
+            sleep(2);
+        }
+        critical_test_exit();
+        eisenberg_exit_critical(id);
+    }
+    exit(0)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let mut v = Vec::new();
+    // TODO: really shuffle
+    assert_eq!(THREAD_NUM, 10);
+    let shuffle: [usize; 10] = [0, 7, 4, 6, 2, 9, 8, 1, 3, 5];
+    for i in 0..THREAD_NUM {
+        v.push(thread_create(thread_fn as usize, shuffle[i]));
+    }
+    for tid in v.iter() {
+        let exit_code = waittid(*tid as usize);
+        assert_eq!(exit_code, 0, "thread conflict happened!");
+        println!("thread#{} exited with code {}", tid, exit_code);
+    }
+    println!("main thread exited.");
+    0
+}

user/src/bin/forktree.rs

@@ -4,7 +4,7 @@
 #[macro_use]
 extern crate user_lib;
 
-use user_lib::{exit, fork, getpid, sleep, yield_};
+use user_lib::{exit, fork, getpid, sleep, wait, yield_};
 
 const DEPTH: usize = 4;
 
@@ -27,11 +27,19 @@ fn fork_tree(cur: &str) {
     println!("pid{}: {}", getpid(), cur);
     fork_child(cur, '0');
     fork_child(cur, '1');
+    let mut exit_code: i32 = 0;
+    for _ in 0..2 {
+        wait(&mut exit_code);
+    }
 }
 
 #[no_mangle]
 pub fn main() -> i32 {
     fork_tree("");
+    let mut exit_code: i32 = 0;
+    for _ in 0..2 {
+        wait(&mut exit_code);
+    }
     sleep(3000);
     0
 }

user/src/bin/getchars.rs

@@ -1,26 +0,0 @@
-#![no_std]
-#![no_main]
-
-#[macro_use]
-extern crate user_lib;
-
-use user_lib::console::getchar;
-
-const N: usize = 10;
-
-#[no_mangle]
-pub fn main() -> i32 {
-    println!("I will receive {} letters.", N);
-    let mut line = [0u8; N];
-    for idx in 0..N {
-        let c = getchar();
-        line[idx] = c;
-    }
-    println!("{} letters entered", N);
-    for idx in 0..N {
-        print!("{}", line[idx] as char);
-    }
-    println!("");
-    println!("You got it!");
-    0
-}

user/src/bin/huge_write.rs

@@ -24,7 +24,7 @@ pub fn main() -> i32 {
     }
     close(f);
     let time_ms = (get_time() - start) as usize;
-    let speed_kbs = size_mb * 1000000 / time_ms;
+    let speed_kbs = (size_mb << 20) / time_ms;
     println!(
         "{}MiB written, time cost = {}ms, write speed = {}KiB/s",
         size_mb, time_ms, speed_kbs

user/src/bin/huge_write_mt.rs

@@ -0,0 +1,56 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::{fmt::format, string::String, vec::Vec};
+use user_lib::{close, get_time, gettid, open, write, OpenFlags};
+use user_lib::{exit, thread_create, waittid};
+
+fn worker(size_kib: usize) {
+    let mut buffer = [0u8; 1024]; // 1KiB
+    for (i, ch) in buffer.iter_mut().enumerate() {
+        *ch = i as u8;
+    }
+    let filename = format(format_args!("testf{}\0", gettid()));
+    let f = open(filename.as_str(), OpenFlags::CREATE | OpenFlags::WRONLY);
+    if f < 0 {
+        panic!("Open test file failed!");
+    }
+    let f = f as usize;
+    for _ in 0..size_kib {
+        write(f, &buffer);
+    }
+    close(f);
+    exit(0)
+}
+
+#[no_mangle]
+pub fn main(argc: usize, argv: &[&str]) -> i32 {
+    assert_eq!(argc, 2, "wrong argument");
+    let size_mb = 1usize;
+    let size_kb = size_mb << 10;
+    let workers = argv[1].parse::<usize>().expect("wrong argument");
+    assert!(workers >= 1 && size_kb % workers == 0, "wrong argument");
+
+    let start = get_time();
+
+    let mut v = Vec::new();
+    let size_mb = 1usize;
+    for _ in 0..workers {
+        v.push(thread_create(worker as usize, size_kb / workers));
+    }
+    for tid in v.iter() {
+        assert_eq!(0, waittid(*tid as usize));
+    }
+
+    let time_ms = (get_time() - start) as usize;
+    let speed_kbs = size_kb * 1000 / time_ms;
+    println!(
+        "{}MiB written by {} threads, time cost = {}ms, write speed = {}KiB/s",
+        size_mb, workers, time_ms, speed_kbs
+    );
+    0
+}

user/src/bin/mpsc_sem.rs

@@ -0,0 +1,73 @@
+#![no_std]
+#![no_main]
+#![allow(clippy::println_empty_string)]
+
+#[macro_use]
+extern crate user_lib;
+
+extern crate alloc;
+
+use alloc::vec::Vec;
+use user_lib::exit;
+use user_lib::{semaphore_create, semaphore_down, semaphore_up};
+use user_lib::{thread_create, waittid};
+
+const SEM_MUTEX: usize = 0;
+const SEM_EMPTY: usize = 1;
+const SEM_EXISTED: usize = 2;
+const BUFFER_SIZE: usize = 8;
+static mut BUFFER: [usize; BUFFER_SIZE] = [0; BUFFER_SIZE];
+static mut FRONT: usize = 0;
+static mut TAIL: usize = 0;
+const PRODUCER_COUNT: usize = 4;
+const NUMBER_PER_PRODUCER: usize = 100;
+
+unsafe fn producer(id: *const usize) -> ! {
+    let id = *id;
+    for _ in 0..NUMBER_PER_PRODUCER {
+        semaphore_down(SEM_EMPTY);
+        semaphore_down(SEM_MUTEX);
+        BUFFER[FRONT] = id;
+        FRONT = (FRONT + 1) % BUFFER_SIZE;
+        semaphore_up(SEM_MUTEX);
+        semaphore_up(SEM_EXISTED);
+    }
+    exit(0)
+}
+
+unsafe fn consumer() -> ! {
+    for _ in 0..PRODUCER_COUNT * NUMBER_PER_PRODUCER {
+        semaphore_down(SEM_EXISTED);
+        semaphore_down(SEM_MUTEX);
+        print!("{} ", BUFFER[TAIL]);
+        TAIL = (TAIL + 1) % BUFFER_SIZE;
+        semaphore_up(SEM_MUTEX);
+        semaphore_up(SEM_EMPTY);
+    }
+    println!("");
+    exit(0)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    // create semaphores
+    assert_eq!(semaphore_create(1) as usize, SEM_MUTEX);
+    assert_eq!(semaphore_create(BUFFER_SIZE) as usize, SEM_EMPTY);
+    assert_eq!(semaphore_create(0) as usize, SEM_EXISTED);
+    // create threads
+    let ids: Vec<_> = (0..PRODUCER_COUNT).collect();
+    let mut threads = Vec::new();
+    for i in 0..PRODUCER_COUNT {
+        threads.push(thread_create(
+            producer as usize,
+            &ids.as_slice()[i] as *const _ as usize,
+        ));
+    }
+    threads.push(thread_create(consumer as usize, 0));
+    // wait for all threads to complete
+    for thread in threads.iter() {
+        waittid(*thread as usize);
+    }
+    println!("mpsc_sem passed!");
+    0
+}

user/src/bin/peterson.rs

@@ -0,0 +1,78 @@
+#![no_std]
+#![no_main]
+#![feature(core_intrinsics)]
+#![feature(asm)]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+extern crate core;
+
+use alloc::vec::Vec;
+use core::sync::atomic::{AtomicUsize, Ordering};
+use user_lib::{exit, sleep, thread_create, waittid};
+const N: usize = 3;
+
+static mut TURN: usize = 0;
+static mut FLAG: [bool; 2] = [false; 2];
+static GUARD: AtomicUsize = AtomicUsize::new(0);
+
+fn critical_test_enter() {
+    assert_eq!(GUARD.fetch_add(1, Ordering::SeqCst), 0);
+}
+
+fn critical_test_claim() {
+    assert_eq!(GUARD.load(Ordering::SeqCst), 1);
+}
+
+fn critical_test_exit() {
+    assert_eq!(GUARD.fetch_sub(1, Ordering::SeqCst), 1);
+}
+
+fn peterson_enter_critical(id: usize, peer_id: usize) {
+    println!("Thread[{}] try enter", id);
+    vstore!(&FLAG[id], true);
+    vstore!(&TURN, peer_id);
+    memory_fence!();
+    while vload!(&FLAG[peer_id]) && vload!(&TURN) == peer_id {
+        println!("Thread[{}] enter fail", id);
+        sleep(1);
+        println!("Thread[{}] retry enter", id);
+    }
+    println!("Thread[{}] enter", id);
+}
+
+fn peterson_exit_critical(id: usize) {
+    vstore!(&FLAG[id], false);
+    println!("Thread[{}] exit", id);
+}
+
+pub fn thread_fn(id: usize) -> ! {
+    println!("Thread[{}] init.", id);
+    let peer_id: usize = id ^ 1;
+    for _ in 0..N {
+        peterson_enter_critical(id, peer_id);
+        critical_test_enter();
+        for _ in 0..3 {
+            critical_test_claim();
+            sleep(2);
+        }
+        critical_test_exit();
+        peterson_exit_critical(id);
+    }
+    exit(0)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let mut v = Vec::new();
+    v.push(thread_create(thread_fn as usize, 0));
+    // v.push(thread_create(thread_fn as usize, 1));
+    for tid in v.iter() {
+        let exit_code = waittid(*tid as usize);
+        assert_eq!(exit_code, 0, "thread conflict happened!");
+        println!("thread#{} exited with code {}", tid, exit_code);
+    }
+    println!("main thread exited.");
+    0
+}

user/src/bin/phil_din_mutex.rs

@@ -0,0 +1,107 @@
+#![no_std]
+#![no_main]
+#![allow(clippy::println_empty_string)]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::vec::Vec;
+use user_lib::{exit, get_time, sleep};
+use user_lib::{mutex_blocking_create, mutex_lock, mutex_unlock};
+use user_lib::{thread_create, waittid};
+
+const N: usize = 5;
+const ROUND: usize = 4;
+// A round: think -> wait for forks -> eat
+const GRAPH_SCALE: usize = 100;
+
+fn get_time_u() -> usize {
+    get_time() as usize
+}
+
+// Time unit: ms
+const ARR: [[usize; ROUND * 2]; N] = [
+    [700, 800, 1000, 400, 500, 600, 200, 400],
+    [300, 600, 200, 700, 1000, 100, 300, 600],
+    [500, 200, 900, 200, 400, 600, 1200, 400],
+    [500, 1000, 600, 500, 800, 600, 200, 900],
+    [600, 100, 600, 600, 200, 500, 600, 200],
+];
+static mut THINK: [[usize; ROUND * 2]; N] = [[0; ROUND * 2]; N];
+static mut EAT: [[usize; ROUND * 2]; N] = [[0; ROUND * 2]; N];
+
+fn philosopher_dining_problem(id: *const usize) {
+    let id = unsafe { *id };
+    let left = id;
+    let right = if id == N - 1 { 0 } else { id + 1 };
+    let min = if left < right { left } else { right };
+    let max = left + right - min;
+    for round in 0..ROUND {
+        // thinking
+        unsafe {
+            THINK[id][2 * round] = get_time_u();
+        }
+        sleep(ARR[id][2 * round]);
+        unsafe {
+            THINK[id][2 * round + 1] = get_time_u();
+        }
+        // wait for forks
+        mutex_lock(min);
+        mutex_lock(max);
+        // eating
+        unsafe {
+            EAT[id][2 * round] = get_time_u();
+        }
+        sleep(ARR[id][2 * round + 1]);
+        unsafe {
+            EAT[id][2 * round + 1] = get_time_u();
+        }
+        mutex_unlock(max);
+        mutex_unlock(min);
+    }
+    exit(0)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let mut v = Vec::new();
+    let ids: Vec<_> = (0..N).collect();
+    let start = get_time_u();
+    for i in 0..N {
+        assert_eq!(mutex_blocking_create(), i as isize);
+        v.push(thread_create(
+            philosopher_dining_problem as usize,
+            &ids.as_slice()[i] as *const _ as usize,
+        ));
+    }
+    for tid in v.iter() {
+        waittid(*tid as usize);
+    }
+    let time_cost = get_time_u() - start;
+    println!("time cost = {}", time_cost);
+    println!("'-' -> THINKING; 'x' -> EATING; ' ' -> WAITING ");
+    for id in (0..N).into_iter().chain(0..=0) {
+        print!("#{}:", id);
+        for j in 0..time_cost / GRAPH_SCALE {
+            let current_time = j * GRAPH_SCALE + start;
+            if (0..ROUND).any(|round| unsafe {
+                let start_thinking = THINK[id][2 * round];
+                let end_thinking = THINK[id][2 * round + 1];
+                start_thinking <= current_time && current_time <= end_thinking
+            }) {
+                print!("-");
+            } else if (0..ROUND).any(|round| unsafe {
+                let start_eating = EAT[id][2 * round];
+                let end_eating = EAT[id][2 * round + 1];
+                start_eating <= current_time && current_time <= end_eating
+            }) {
+                print!("x");
+            } else {
+                print!(" ");
+            };
+        }
+        println!("");
+    }
+    0
+}

user/src/bin/pipe_shell.rs

@@ -1,201 +0,0 @@
-// https://www.joshmcguigan.com/blog/build-your-own-shell-rust/
-// https://github.com/JoshMcguigan/bubble-shell
-// https://github.com/psinghal20/rush
-#![no_std]
-#![no_main]
-
-extern crate alloc;
-
-#[macro_use]
-extern crate user_lib;
-
-const LF: u8 = 0x0au8;
-const CR: u8 = 0x0du8;
-const DL: u8 = 0x7fu8;
-const BS: u8 = 0x08u8;
-
-use alloc::string::String;
-use alloc::vec::Vec;
-use user_lib::console::{getchar};
-use user_lib::{close, dup, exec, fork, open, pipe, waitpid, OpenFlags};
-
-const STDIN: usize = 0;
-const STDOUT: usize = 1;
-
-#[derive(Debug, Clone)]
-enum IOType {
-    File(String),
-    // [read end, write end]
-    Pipe([usize; 2]),
-    Inherit,
-}
-
-impl IOType {
-    pub fn new_pipe() -> Self {
-        let mut pipe_fd: [usize; 2] = [0; 2];
-        pipe(&mut pipe_fd);
-        Self::Pipe(pipe_fd)
-    }
-}
-
-#[derive(Debug, Clone)]
-struct Process {
-    pub pid: isize,
-    pub output: IOType,
-}
-
-#[no_mangle]
-pub fn main() -> i32 {
-    println!("Rust user shell (with pipe)");
-    let mut line: String = String::new();
-    print!(">) ");
-    //flush();
-    loop {
-        let c = getchar();
-        match c {
-            LF | CR => {
-                println!("");
-                if !line.is_empty() {
-                    let mut commands = line.trim().split(" | ").peekable();
-
-                    let mut previous_process: Option<Process> = None;
-                    while let Some(command) = commands.next() {
-                        let args: Vec<_> = command.trim().split(' ').collect();
-                        let mut args_copy: Vec<String> = args
-                            .iter()
-                            .map(|&arg| {
-                                let mut string = String::new();
-                                string.push_str(arg);
-                                string.push('\0');
-                                string
-                            })
-                            .collect();
-
-                        // redirect input
-                        let input = if previous_process.is_some() {
-                            previous_process.clone().unwrap().output
-                        } else if let Some((idx, _)) = args_copy
-                            .iter()
-                            .enumerate()
-                            .find(|(_, arg)| arg.as_str() == "<\0")
-                        {
-                            let tmp = IOType::File(args_copy[idx + 1].clone());
-                            args_copy.drain(idx..=idx + 1);
-                            tmp
-                        } else {
-                            IOType::Inherit
-                        };
-
-                        // redirect output
-                        let output = if commands.peek().is_some() {
-                            IOType::new_pipe()
-                        } else if let Some((idx, _)) = args_copy
-                            .iter()
-                            .enumerate()
-                            .find(|(_, arg)| arg.as_str() == ">\0")
-                        {
-                            let tmp = IOType::File(args_copy[idx + 1].clone());
-                            args_copy.drain(idx..=idx + 1);
-                            tmp
-                        } else {
-                            IOType::Inherit
-                        };
-
-                        let mut args_addr: Vec<*const u8> =
-                            args_copy.iter().map(|arg| arg.as_ptr()).collect();
-                        args_addr.push(0 as *const u8);
-                        let pid = fork();
-                        if pid == 0 {
-                            // input redirection
-                            match input.clone() {
-                                IOType::File(filename) => {
-                                    let input_fd = open(filename.as_str(), OpenFlags::RDONLY);
-                                    if input_fd == -1 {
-                                        println!("Error when opening file {}", filename);
-                                        return -4;
-                                    }
-                                    let input_fd = input_fd as usize;
-                                    close(STDIN);
-                                    assert_eq!(dup(input_fd) as usize, STDIN);
-                                    close(input_fd);
-                                }
-                                IOType::Pipe(pipes) => {
-                                    close(pipes[1]); // close write end
-                                    close(STDIN);
-                                    assert_eq!(dup(pipes[0]) as usize, STDIN);
-                                    close(pipes[0]);
-                                }
-                                _ => {}
-                            }
-                            // output redirection
-                            match output.clone() {
-                                IOType::File(filename) => {
-                                    let output_fd = open(
-                                        filename.as_str(),
-                                        OpenFlags::CREATE | OpenFlags::WRONLY,
-                                    );
-                                    if output_fd == -1 {
-                                        println!("Error when opening file {}", filename);
-                                        return -4;
-                                    }
-                                    let output_fd = output_fd as usize;
-                                    close(STDOUT);
-                                    assert_eq!(dup(output_fd) as usize, STDOUT);
-                                    close(output_fd);
-                                }
-                                IOType::Pipe(pipes) => {
-                                    close(pipes[0]); // close read end
-                                    close(STDOUT);
-                                    assert_eq!(dup(pipes[1]) as usize, STDOUT);
-                                    close(pipes[1]);
-                                }
-                                _ => {}
-                            }
-                            // run child process
-                            if exec(args_copy[0].as_str(), args_addr.as_slice()) == -1 {
-                                println!("Error when executing!");
-                                return -4;
-                            }
-                            unreachable!("Should not happen!");
-                        }
-                        // old pipe was done, close it.
-                        if let Some(p) = previous_process {
-                            match p.output {
-                                IOType::Pipe(pipes) => {
-                                    close(pipes[0]);
-                                    close(pipes[1]);
-                                }
-                                _ => {}
-                            }
-                        }
-                        previous_process = Some(Process { pid, output });
-                    }
-                    line.clear();
-                    if let Some(process) = previous_process {
-                        let mut exit_code: i32 = 0;
-                        let pid = process.pid;
-                        let exit_pid = waitpid(pid as usize, &mut exit_code);
-                        assert_eq!(pid, exit_pid);
-                        println!("Shell: Process {} exited with code {}", pid, exit_code);
-                    }
-                }
-                print!(">) ");
-                //flush();
-            }
-            BS | DL => {
-                if !line.is_empty() {
-                    print!("{}", BS as char);
-                    print!(" ");
-                    print!("{}", BS as char);
-                    //flush();
-                    line.pop();
-                }
-            }
-            _ => {
-                print!("{}", c as char);
-                //flush();
-                line.push(c as char);
-            }
-        }
-    }
-}

user/src/bin/race_adder.rs

@@ -0,0 +1,42 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::vec::Vec;
+use user_lib::{exit, get_time, thread_create, waittid};
+
+static mut A: usize = 0;
+const PER_THREAD: usize = 1000;
+const THREAD_COUNT: usize = 16;
+
+unsafe fn f() -> ! {
+    let mut t = 2usize;
+    for _ in 0..PER_THREAD {
+        let a = &mut A as *mut usize;
+        let cur = a.read_volatile();
+        for _ in 0..500 {
+            t = t * t % 10007;
+        }
+        a.write_volatile(cur + 1);
+    }
+    exit(t as i32)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let start = get_time();
+    let mut v = Vec::new();
+    for _ in 0..THREAD_COUNT {
+        v.push(thread_create(f as usize, 0) as usize);
+    }
+    let mut time_cost = Vec::new();
+    for tid in v.iter() {
+        time_cost.push(waittid(*tid));
+    }
+    println!("time cost is {}ms", get_time() - start);
+    assert_eq!(unsafe { A }, PER_THREAD * THREAD_COUNT);
+    0
+}

user/src/bin/race_adder_arg.rs

@@ -0,0 +1,56 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use crate::alloc::string::ToString;
+use alloc::vec::Vec;
+use user_lib::{exit, get_time, thread_create, waittid};
+
+static mut A: usize = 0;
+const PER_THREAD: usize = 1000;
+const THREAD_COUNT: usize = 16;
+
+unsafe fn f(count: usize) -> ! {
+    let mut t = 2usize;
+    for _ in 0..PER_THREAD {
+        let a = &mut A as *mut usize;
+        let cur = a.read_volatile();
+        for _ in 0..count {
+            t = t * t % 10007;
+        }
+        a.write_volatile(cur + 1);
+    }
+    exit(t as i32)
+}
+
+#[no_mangle]
+pub fn main(argc: usize, argv: &[&str]) -> i32 {
+    let count: usize;
+    if argc == 1 {
+        count = THREAD_COUNT;
+    } else if argc == 2 {
+        count = argv[1].to_string().parse::<usize>().unwrap();
+    } else {
+        println!(
+            "ERROR in argv, argc is {}, argv[0] {} , argv[1] {} , argv[2] {}",
+            argc, argv[0], argv[1], argv[2]
+        );
+        exit(-1);
+    }
+
+    let start = get_time();
+    let mut v = Vec::new();
+    for _ in 0..THREAD_COUNT {
+        v.push(thread_create(f as usize, count) as usize);
+    }
+    let mut time_cost = Vec::new();
+    for tid in v.iter() {
+        time_cost.push(waittid(*tid));
+    }
+    println!("time cost is {}ms", get_time() - start);
+    assert_eq!(unsafe { A }, PER_THREAD * THREAD_COUNT);
+    0
+}

user/src/bin/race_adder_atomic.rs

@@ -0,0 +1,51 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::vec::Vec;
+use core::sync::atomic::{AtomicBool, Ordering};
+use user_lib::{exit, get_time, thread_create, waittid, yield_};
+
+static mut A: usize = 0;
+static OCCUPIED: AtomicBool = AtomicBool::new(false);
+const PER_THREAD: usize = 1000;
+const THREAD_COUNT: usize = 16;
+
+unsafe fn f() -> ! {
+    let mut t = 2usize;
+    for _ in 0..PER_THREAD {
+        while OCCUPIED
+            .compare_exchange(false, true, Ordering::Relaxed, Ordering::Relaxed)
+            .is_err()
+        {
+            yield_();
+        }
+        let a = &mut A as *mut usize;
+        let cur = a.read_volatile();
+        for _ in 0..500 {
+            t = t * t % 10007;
+        }
+        a.write_volatile(cur + 1);
+        OCCUPIED.store(false, Ordering::Relaxed);
+    }
+    exit(t as i32)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let start = get_time();
+    let mut v = Vec::new();
+    for _ in 0..THREAD_COUNT {
+        v.push(thread_create(f as usize, 0) as usize);
+    }
+    let mut time_cost = Vec::new();
+    for tid in v.iter() {
+        time_cost.push(waittid(*tid));
+    }
+    println!("time cost is {}ms", get_time() - start);
+    assert_eq!(unsafe { A }, PER_THREAD * THREAD_COUNT);
+    0
+}

user/src/bin/race_adder_loop.rs

@@ -0,0 +1,51 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::vec::Vec;
+use user_lib::{exit, get_time, thread_create, waittid, yield_};
+
+static mut A: usize = 0;
+static mut OCCUPIED: bool = false;
+const PER_THREAD: usize = 1000;
+const THREAD_COUNT: usize = 16;
+
+unsafe fn f() -> ! {
+    let mut t = 2usize;
+    for _ in 0..PER_THREAD {
+        while OCCUPIED {
+            yield_();
+        }
+        OCCUPIED = true;
+        // enter critical section
+        let a = &mut A as *mut usize;
+        let cur = a.read_volatile();
+        for _ in 0..500 {
+            t = t * t % 10007;
+        }
+        a.write_volatile(cur + 1);
+        // exit critical section
+        OCCUPIED = false;
+    }
+
+    exit(t as i32)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let start = get_time();
+    let mut v = Vec::new();
+    for _ in 0..THREAD_COUNT {
+        v.push(thread_create(f as usize, 0) as usize);
+    }
+    let mut time_cost = Vec::new();
+    for tid in v.iter() {
+        time_cost.push(waittid(*tid));
+    }
+    println!("time cost is {}ms", get_time() - start);
+    assert_eq!(unsafe { A }, PER_THREAD * THREAD_COUNT);
+    0
+}

user/src/bin/race_adder_mutex_blocking.rs

@@ -0,0 +1,46 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::vec::Vec;
+use user_lib::{exit, get_time, thread_create, waittid};
+use user_lib::{mutex_blocking_create, mutex_lock, mutex_unlock};
+
+static mut A: usize = 0;
+const PER_THREAD: usize = 1000;
+const THREAD_COUNT: usize = 16;
+
+unsafe fn f() -> ! {
+    let mut t = 2usize;
+    for _ in 0..PER_THREAD {
+        mutex_lock(0);
+        let a = &mut A as *mut usize;
+        let cur = a.read_volatile();
+        for _ in 0..500 {
+            t = t * t % 10007;
+        }
+        a.write_volatile(cur + 1);
+        mutex_unlock(0);
+    }
+    exit(t as i32)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let start = get_time();
+    assert_eq!(mutex_blocking_create(), 0);
+    let mut v = Vec::new();
+    for _ in 0..THREAD_COUNT {
+        v.push(thread_create(f as usize, 0) as usize);
+    }
+    let mut time_cost = Vec::new();
+    for tid in v.iter() {
+        time_cost.push(waittid(*tid));
+    }
+    println!("time cost is {}ms", get_time() - start);
+    assert_eq!(unsafe { A }, PER_THREAD * THREAD_COUNT);
+    0
+}

user/src/bin/race_adder_mutex_spin.rs

@@ -0,0 +1,46 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::vec::Vec;
+use user_lib::{exit, get_time, thread_create, waittid};
+use user_lib::{mutex_create, mutex_lock, mutex_unlock};
+
+static mut A: usize = 0;
+const PER_THREAD: usize = 1000;
+const THREAD_COUNT: usize = 16;
+
+unsafe fn f() -> ! {
+    let mut t = 2usize;
+    for _ in 0..PER_THREAD {
+        mutex_lock(0);
+        let a = &mut A as *mut usize;
+        let cur = a.read_volatile();
+        for _ in 0..500 {
+            t = t * t % 10007;
+        }
+        a.write_volatile(cur + 1);
+        mutex_unlock(0);
+    }
+    exit(t as i32)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let start = get_time();
+    assert_eq!(mutex_create(), 0);
+    let mut v = Vec::new();
+    for _ in 0..THREAD_COUNT {
+        v.push(thread_create(f as usize, 0) as usize);
+    }
+    let mut time_cost = Vec::new();
+    for tid in v.iter() {
+        time_cost.push(waittid(*tid));
+    }
+    println!("time cost is {}ms", get_time() - start);
+    assert_eq!(unsafe { A }, PER_THREAD * THREAD_COUNT);
+    0
+}

user/src/bin/run_pipe_test.rs

@@ -8,7 +8,7 @@ use user_lib::{exec, fork, wait};
 
 #[no_mangle]
 pub fn main() -> i32 {
-    for i in 0..1000 {
+    for i in 0..50 {
         if fork() == 0 {
             exec("pipe_large_test\0", &[core::ptr::null::<u8>()]);
         } else {

user/src/bin/sig_simple.rs

@@ -1,32 +0,0 @@
-#![no_std]
-#![no_main]
-
-#[macro_use]
-extern crate user_lib;
-
-// use user_lib::{sigaction, sigprocmask, SignalAction, SignalFlags, fork, exit, wait, kill, getpid, sleep, sigreturn};
-use user_lib::*;
-
-fn func() {
-    println!("user_sig_test succsess");
-    sigreturn();
-}
-
-#[no_mangle]
-pub fn main() -> i32 {
-    let mut new = SignalAction::default();
-    let old = SignalAction::default();
-    new.handler = func as usize;
-
-    println!("signal_simple: sigaction");
-    if sigaction(SIGUSR1, &new, &old) < 0 {
-        panic!("Sigaction failed!");
-    }
-    println!("signal_simple: kill");
-    if kill(getpid() as usize, SIGUSR1) < 0 {
-        println!("Kill failed!");
-        exit(1);
-    }
-    println!("signal_simple: Done");
-    0
-}

user/src/bin/sig_simple2.rs

@@ -1,44 +0,0 @@
-#![no_std]
-#![no_main]
-
-#[macro_use]
-extern crate user_lib;
-
-use user_lib::{sigaction, sigprocmask, SignalAction, SignalFlags, fork, exit, waitpid, kill, getpid, sleep, sigreturn};
-
-fn func() {
-    println!("user_sig_test succsess");
-    sigreturn();
-}
-
-#[no_mangle]
-pub fn main() -> i32 {
-    let pid = fork();
-    if pid==0{
-        let mut new = SignalAction::default();
-        let old = SignalAction::default();
-        new.handler = func as usize;
-
-        println!("signal_simple2: child sigaction");
-        if sigaction(10, &new, &old) < 0 {
-            panic!("Sigaction failed!");
-        }
-        sleep(1000);
-        println!("signal_simple2: child done");
-        exit(0);
-    } else if pid >0 {
-        println!("signal_simple2: parent kill child");
-        sleep(500);
-        if kill(pid as usize, 1<<10) < 0 {
-            println!("Kill failed!");
-            exit(1);
-        }
-        println!("signal_simple2: parent wait child");
-        let mut exit_code = 0;
-        waitpid(pid as usize, &mut exit_code);
-        println!("signal_simple2: parent Done");
-        exit(0);
-    }
-   
-    0
-}

user/src/bin/sig_tests.rs

@@ -1,204 +0,0 @@
-#![no_std]
-#![no_main]
-
-#[macro_use]
-extern crate user_lib;
-
-// use user_lib::{sigaction, sigprocmask, SignalAction, SignalFlags, fork, exit, wait, kill, getpid, sleep, sigreturn};
-use user_lib::*;
-
-fn func() {
-    println!("user_sig_test succsess");
-    sigreturn();
-}
-
-fn func2() {
-    loop {
-        print!("");
-    }
-}
-
-fn func3() {
-    println!("interrupt");
-    sigreturn();
-}
-
-fn user_sig_test_failsignum() {
-    let mut new = SignalAction::default();
-    let old = SignalAction::default();
-    new.handler = func as usize;
-    if sigaction(50, &new, &old) >= 0 {
-        panic!("Wrong sigaction but success!");
-    }
-}
-
-fn user_sig_test_kill() {
-    let mut new = SignalAction::default();
-    let old = SignalAction::default();
-    new.handler = func as usize;
-
-    if sigaction(SIGUSR1, &new, &old) < 0 {
-        panic!("Sigaction failed!");
-    }
-    if kill(getpid() as usize, SIGUSR1) < 0 {
-        println!("Kill failed!");
-        exit(1);
-    }
-}
-
-fn user_sig_test_multiprocsignals() {
-    let pid= fork();
-    if pid == 0{
-        let mut new = SignalAction::default();
-        let old = SignalAction::default();
-        new.handler = func as usize;
-        if sigaction(SIGUSR1, &new, &old) < 0 {
-            panic!("Sigaction failed!");
-        }
-    } else {
-        if kill(pid as usize, SIGUSR1) < 0 {
-            println!("Kill failed!");
-            exit(1);
-        }
-        let mut exit_code = 0;
-        wait(&mut exit_code);
-    }
-}
-
-fn user_sig_test_restore() {
-    let mut new = SignalAction::default();
-    let old = SignalAction::default();
-    let old2 = SignalAction::default();
-    new.handler = func as usize;
-
-    if sigaction(SIGUSR1, &new, &old) < 0 {
-        panic!("Sigaction failed!");
-    }
-
-    if sigaction(SIGUSR1, &old, &old2) < 0 {
-        panic!("Sigaction failed!");
-    }
-
-    if old2.handler != new.handler {
-        println!("Restore failed!");
-        exit(-1);
-    }
-}
-
-fn kernel_sig_test_ignore() {
-    sigprocmask(SignalFlags::SIGSTOP.bits() as u32);
-    if kill(getpid() as usize, SignalFlags::SIGSTOP.bits()) < 0{
-        println!("kill faild\n");
-        exit(-1);
-    }
-}
-
-fn kernel_sig_test_stop_cont() {
-    let pid= fork();
-    if pid == 0 {
-        kill(getpid() as usize, SignalFlags::SIGSTOP.bits());
-        sleep(1000);
-        exit(-1);
-    } else {
-        sleep(5000);
-        kill(pid as usize, SignalFlags::SIGCONT.bits());
-        let mut exit_code = 0;
-        wait(&mut exit_code);
-    }
-}
-
-fn kernel_sig_test_failignorekill() {
-    let mut new = SignalAction::default();
-    let old = SignalAction::default();
-    new.handler = func as usize;
-
-    if sigaction(9, &new, &old) >= 0 {
-        panic!("Should not set sigaction to kill!");
-    }
-
-    if sigaction(9, &new, 0 as *const SignalAction) >= 0 {
-        panic!("Should not set sigaction to kill!");
-    }
-
-    if sigaction(9, 0 as *const SignalAction, &old) >= 0 {
-        panic!("Should not set sigaction to kill!");
-    }
-}
-
-fn final_sig_test() {
-    let mut new = SignalAction::default();
-    let old = SignalAction::default();
-    new.handler = func2 as usize;
-
-    let mut new2 = SignalAction::default();
-    let old2 = SignalAction::default();
-    new2.handler = func3 as usize;
-
-    let pid= fork();
-    if pid == 0{
-        if sigaction(SIGUSR1, &new, &old) < 0 {
-            panic!("Sigaction failed!");
-        }
-        if sigaction(14, &new2, &old2) < 0 {
-            panic!("Sigaction failed!");
-        }
-        if kill(getpid() as usize, SIGUSR1) < 0 {
-            println!("Kill failed!");
-            exit(-1);
-        }
-    } else {
-        sleep(1000);
-        if kill(pid as usize, 1 << 14) < 0 {
-            println!("Kill failed!");
-            exit(-1);
-        }
-        sleep(1000);
-        kill(pid as usize, SignalFlags::SIGKILL.bits());
-    }
-}
-
-
-fn run(f: fn()) -> bool {
-    let pid = fork();
-    if pid == 0 {
-        f();
-        exit(0);
-    } else {
-        let mut exit_code: i32 = 0;
-        wait(&mut exit_code);
-        if exit_code != 0 {
-            println!("FAILED!");
-        } else {
-            println!("OK!");
-        }
-        exit_code == 0
-    }
-}
-
-#[no_mangle]
-pub fn main() -> i32 {
-    let tests: [(fn(), &str); 8] = [
-        (user_sig_test_failsignum, "user_sig_test_failsignum"),
-        (user_sig_test_kill, "user_sig_test_kill"),
-        (user_sig_test_multiprocsignals, "user_sig_test_multiprocsignals"),
-        (user_sig_test_restore, "user_sig_test_restore"),
-        (kernel_sig_test_ignore, "kernel_sig_test_ignore"),
-        (kernel_sig_test_stop_cont, "kernel_sig_test_stop_cont"),
-        (kernel_sig_test_failignorekill, "kernel_sig_test_failignorekill"),
-        (final_sig_test, "final_sig_test")
-    ];
-    let mut fail_num = 0;
-    for test in tests {
-        println!("Testing {}", test.1);
-        if !run(test.0) {
-            fail_num += 1;
-        }
-    }
-    if fail_num == 0 {
-        println!("ALL TESTS PASSED");
-        0
-    } else {
-        println!("SOME TESTS FAILED");
-        -1
-    }
-}

user/src/bin/sync_sem.rs

@@ -0,0 +1,45 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+extern crate alloc;
+
+use alloc::vec;
+use user_lib::exit;
+use user_lib::{semaphore_create, semaphore_down, semaphore_up};
+use user_lib::{sleep, thread_create, waittid};
+
+const SEM_SYNC: usize = 0;
+
+unsafe fn first() -> ! {
+    sleep(10);
+    println!("First work and wakeup Second");
+    semaphore_up(SEM_SYNC);
+    exit(0)
+}
+
+unsafe fn second() -> ! {
+    println!("Second want to continue,but need to wait first");
+    semaphore_down(SEM_SYNC);
+    println!("Second can work now");
+    exit(0)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    // create semaphores
+    assert_eq!(semaphore_create(0) as usize, SEM_SYNC);
+    // create threads
+    let threads = vec![
+        thread_create(first as usize, 0),
+        thread_create(second as usize, 0),
+    ];
+    // wait for all threads to complete
+    for thread in threads.iter() {
+        waittid(*thread as usize);
+    }
+    println!("sync_sem passed!");
+    0
+}

user/src/bin/test_condvar.rs

@@ -0,0 +1,59 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+extern crate alloc;
+
+use alloc::vec;
+use user_lib::exit;
+use user_lib::{
+    condvar_create, condvar_signal, condvar_wait, mutex_blocking_create, mutex_lock, mutex_unlock,
+};
+use user_lib::{sleep, thread_create, waittid};
+
+static mut A: usize = 0;
+
+const CONDVAR_ID: usize = 0;
+const MUTEX_ID: usize = 0;
+
+unsafe fn first() -> ! {
+    sleep(10);
+    println!("First work, Change A --> 1 and wakeup Second");
+    mutex_lock(MUTEX_ID);
+    A = 1;
+    condvar_signal(CONDVAR_ID);
+    mutex_unlock(MUTEX_ID);
+    exit(0)
+}
+
+unsafe fn second() -> ! {
+    println!("Second want to continue,but need to wait A=1");
+    mutex_lock(MUTEX_ID);
+    while A == 0 {
+        println!("Second: A is {}", A);
+        condvar_wait(CONDVAR_ID, MUTEX_ID);
+    }
+    mutex_unlock(MUTEX_ID);
+    println!("A is {}, Second can work now", A);
+    exit(0)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    // create condvar & mutex
+    assert_eq!(condvar_create() as usize, CONDVAR_ID);
+    assert_eq!(mutex_blocking_create() as usize, MUTEX_ID);
+    // create threads
+    let threads = vec![
+        thread_create(first as usize, 0),
+        thread_create(second as usize, 0),
+    ];
+    // wait for all threads to complete
+    for thread in threads.iter() {
+        waittid(*thread as usize);
+    }
+    println!("test_condvar passed!");
+    0
+}

user/src/bin/threads.rs

@@ -0,0 +1,45 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::vec;
+use user_lib::{exit, thread_create, waittid};
+
+pub fn thread_a() -> ! {
+    for _ in 0..1000 {
+        print!("a");
+    }
+    exit(1)
+}
+
+pub fn thread_b() -> ! {
+    for _ in 0..1000 {
+        print!("b");
+    }
+    exit(2)
+}
+
+pub fn thread_c() -> ! {
+    for _ in 0..1000 {
+        print!("c");
+    }
+    exit(3)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let v = vec![
+        thread_create(thread_a as usize, 0),
+        thread_create(thread_b as usize, 0),
+        thread_create(thread_c as usize, 0),
+    ];
+    for tid in v.iter() {
+        let exit_code = waittid(*tid as usize);
+        println!("thread#{} exited with code {}", tid, exit_code);
+    }
+    println!("main thread exited.");
+    0
+}

user/src/bin/threads_arg.rs

@@ -0,0 +1,44 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+extern crate alloc;
+
+use alloc::vec::Vec;
+use user_lib::{exit, thread_create, waittid};
+
+struct Argument {
+    pub ch: char,
+    pub rc: i32,
+}
+
+fn thread_print(arg: *const Argument) -> ! {
+    let arg = unsafe { &*arg };
+    for _ in 0..1000 {
+        print!("{}", arg.ch);
+    }
+    exit(arg.rc)
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let mut v = Vec::new();
+    let args = [
+        Argument { ch: 'a', rc: 1 },
+        Argument { ch: 'b', rc: 2 },
+        Argument { ch: 'c', rc: 3 },
+    ];
+    for arg in args.iter() {
+        v.push(thread_create(
+            thread_print as usize,
+            arg as *const _ as usize,
+        ));
+    }
+    for tid in v.iter() {
+        let exit_code = waittid(*tid as usize);
+        println!("thread#{} exited with code {}", tid, exit_code);
+    }
+    println!("main thread exited.");
+    0
+}

user/src/bin/usertests.rs

@@ -4,40 +4,138 @@
 #[macro_use]
 extern crate user_lib;
 
-static TESTS: &[&str] = &[
-    "exit\0",
-    "fantastic_text\0",
-    "forktest\0",
-    "forktest2\0",
-    "forktest_simple\0",
-    "hello_world\0",
-    "matrix\0",
-    "sleep\0",
-    "sleep_simple\0",
-    "stack_overflow\0",
-    "yield\0",
+// not in SUCC_TESTS & FAIL_TESTS
+// count_lines, infloop, user_shell, usertests
+
+// item of TESTS : app_name(argv_0), argv_1, argv_2, argv_3, exit_code
+static SUCC_TESTS: &[(&str, &str, &str, &str, i32)] = &[
+    ("filetest_simple\0", "\0", "\0", "\0", 0),
+    ("cat\0", "filea\0", "\0", "\0", 0),
+    ("cmdline_args\0", "1\0", "2\0", "3\0", 0),
+    ("eisenberg\0", "\0", "\0", "\0", 0),
+    ("exit\0", "\0", "\0", "\0", 0),
+    ("fantastic_text\0", "\0", "\0", "\0", 0),
+    ("forktest_simple\0", "\0", "\0", "\0", 0),
+    ("forktest\0", "\0", "\0", "\0", 0),
+    ("forktest2\0", "\0", "\0", "\0", 0),
+    ("forktree\0", "\0", "\0", "\0", 0),
+    ("hello_world\0", "\0", "\0", "\0", 0),
+    ("huge_write\0", "\0", "\0", "\0", 0),
+    ("matrix\0", "\0", "\0", "\0", 0),
+    ("mpsc_sem\0", "\0", "\0", "\0", 0),
+    ("peterson\0", "\0", "\0", "\0", 0),
+    ("phil_din_mutex\0", "\0", "\0", "\0", 0),
+    ("pipe_large_test\0", "\0", "\0", "\0", 0),
+    ("pipetest\0", "\0", "\0", "\0", 0),
+    ("race_adder_arg\0", "3\0", "\0", "\0", 0),
+    ("race_adder_atomic\0", "\0", "\0", "\0", 0),
+    ("race_adder_mutex_blocking\0", "\0", "\0", "\0", 0),
+    ("race_adder_mutex_spin\0", "\0", "\0", "\0", 0),
+    ("run_pipe_test\0", "\0", "\0", "\0", 0),
+    ("sleep_simple\0", "\0", "\0", "\0", 0),
+    ("sleep\0", "\0", "\0", "\0", 0),
+    ("sleep_simple\0", "\0", "\0", "\0", 0),
+    ("sync_sem\0", "\0", "\0", "\0", 0),
+    ("test_condvar\0", "\0", "\0", "\0", 0),
+    ("threads_arg\0", "\0", "\0", "\0", 0),
+    ("threads\0", "\0", "\0", "\0", 0),
+    ("yield\0", "\0", "\0", "\0", 0),
+];
+
+static FAIL_TESTS: &[(&str, &str, &str, &str, i32)] = &[
+    ("stack_overflow\0", "\0", "\0", "\0", -11),
+    ("race_adder_loop\0", "\0", "\0", "\0", -6),
+    ("priv_csr\0", "\0", "\0", "\0", -4),
+    ("priv_inst\0", "\0", "\0", "\0", -4),
+    ("store_fault\0", "\0", "\0", "\0", -11),
+    ("until_timeout\0", "\0", "\0", "\0", -6),
+    ("race_adder\0", "\0", "\0", "\0", -6),
+    ("huge_write_mt\0", "\0", "\0", "\0", -6),
 ];
 
 use user_lib::{exec, fork, waitpid};
 
-#[no_mangle]
-pub fn main() -> i32 {
-    for test in TESTS {
-        println!("Usertests: Running {}", test);
+fn run_tests(tests: &[(&str, &str, &str, &str, i32)]) -> i32 {
+    let mut pass_num = 0;
+    let mut arr: [*const u8; 4] = [
+        core::ptr::null::<u8>(),
+        core::ptr::null::<u8>(),
+        core::ptr::null::<u8>(),
+        core::ptr::null::<u8>(),
+    ];
+
+    for test in tests {
+        println!("Usertests: Running {}", test.0);
+        arr[0] = test.0.as_ptr();
+        if test.1 != "\0" {
+            arr[1] = test.1.as_ptr();
+            arr[2] = core::ptr::null::<u8>();
+            arr[3] = core::ptr::null::<u8>();
+            if test.2 != "\0" {
+                arr[2] = test.2.as_ptr();
+                arr[3] = core::ptr::null::<u8>();
+                if test.3 != "\0" {
+                    arr[3] = test.3.as_ptr();
+                } else {
+                    arr[3] = core::ptr::null::<u8>();
+                }
+            } else {
+                arr[2] = core::ptr::null::<u8>();
+                arr[3] = core::ptr::null::<u8>();
+            }
+        } else {
+            arr[1] = core::ptr::null::<u8>();
+            arr[2] = core::ptr::null::<u8>();
+            arr[3] = core::ptr::null::<u8>();
+        }
+
         let pid = fork();
         if pid == 0 {
-            exec(*test, &[core::ptr::null::<u8>()]);
+            exec(test.0, &arr[..]);
             panic!("unreachable!");
         } else {
             let mut exit_code: i32 = Default::default();
             let wait_pid = waitpid(pid as usize, &mut exit_code);
             assert_eq!(pid, wait_pid);
+            if exit_code == test.4 {
+                // summary apps with  exit_code
+                pass_num = pass_num + 1;
+            }
             println!(
                 "\x1b[32mUsertests: Test {} in Process {} exited with code {}\x1b[0m",
-                test, pid, exit_code
+                test.0, pid, exit_code
             );
         }
     }
-    println!("Usertests passed!");
-    0
+    pass_num
+}
+
+#[no_mangle]
+pub fn main() -> i32 {
+    let succ_num = run_tests(SUCC_TESTS);
+    let err_num = run_tests(FAIL_TESTS);
+    if succ_num == SUCC_TESTS.len() as i32 && err_num == FAIL_TESTS.len() as i32 {
+        println!(
+            "{} of sueecssed apps, {} of failed apps run correctly. \nUsertests passed!",
+            SUCC_TESTS.len(),
+            FAIL_TESTS.len()
+        );
+        return 0;
+    }
+    if succ_num != SUCC_TESTS.len() as i32 {
+        println!(
+            "all successed app_num is  {} , but only  passed {}",
+            SUCC_TESTS.len(),
+            succ_num
+        );
+    }
+    if err_num != FAIL_TESTS.len() as i32 {
+        println!(
+            "all failed app_num is  {} , but only  passed {}",
+            FAIL_TESTS.len(),
+            err_num
+        );
+    }
+    println!(" Usertests failed!");
+    return -1;
 }

user/src/lib.rs

@@ -2,6 +2,7 @@
 #![feature(linkage)]
 #![feature(panic_info_message)]
 #![feature(alloc_error_handler)]
+#![feature(core_intrinsics)]
 
 #[macro_use]
 pub mod console;
@@ -132,112 +133,89 @@ pub fn waitpid_nb(pid: usize, exit_code: &mut i32) -> isize {
     sys_waitpid(pid as isize, exit_code as *mut _)
 }
 
-pub fn sleep(period_ms: usize) {
-    let start = sys_get_time();
-    while sys_get_time() < start + period_ms as isize {
-        sys_yield();
+bitflags! {
+    pub struct SignalFlags: i32 {
+        const SIGINT    = 1 << 2;
+        const SIGILL    = 1 << 4;
+        const SIGABRT   = 1 << 6;
+        const SIGFPE    = 1 << 8;
+        const SIGSEGV   = 1 << 11;
     }
 }
 
-/// Action for a signal
-#[repr(C)]
-#[derive(Debug, Clone, Copy)]
-pub struct SignalAction {
-    pub handler: usize, 
-    pub mask: SignalFlags
+pub fn kill(pid: usize, signal: i32) -> isize {
+    sys_kill(pid, signal)
 }
 
-impl Default for SignalAction {
-    fn default() -> Self {
-        Self {
-            handler: 0,
-            mask: SignalFlags::empty()
-        }
-    }
+pub fn sleep(sleep_ms: usize) {
+    sys_sleep(sleep_ms);
 }
 
-pub const SIGDEF :i32 = 1; // Default signal handling
-pub const SIGHUP :i32 = 1;
-pub const SIGINT :i32 = 2;
-pub const SIGQUIT :i32 = 3;
-pub const SIGILL :i32 = 4;
-pub const SIGTRAP :i32 = 5;
-pub const SIGABRT :i32 = 6;
-pub const SIGBUS :i32 = 7;
-pub const SIGFPE :i32 = 8;
-pub const SIGKILL :i32 = 9;
-pub const SIGUSR1 :i32 = 10;
-pub const SIGSEGV :i32 = 11;
-pub const SIGUSR2 :i32 = 12;
-pub const SIGPIPE :i32 = 13;
-pub const SIGALRM :i32 = 14;
-pub const SIGTERM :i32 = 15;
-pub const SIGSTKFLT :i32 = 16;
-pub const SIGCHLD :i32 = 17;
-pub const SIGCONT :i32 = 18;
-pub const SIGSTOP :i32 = 19;
-pub const SIGTSTP :i32 = 20;
-pub const SIGTTIN :i32 = 21;
-pub const SIGTTOU :i32 = 22;
-pub const SIGURG :i32 = 23;
-pub const SIGXCPU :i32 = 24;
-pub const SIGXFSZ :i32 = 25;
-pub const SIGVTALRM :i32 = 26;
-pub const SIGPROF :i32 = 27;
-pub const SIGWINCH :i32 = 28;
-pub const SIGIO :i32 = 29;
-pub const SIGPWR :i32 = 30;
-pub const SIGSYS :i32 = 31;
-
-bitflags! {
-    pub struct SignalFlags: i32 {
-        const SIGDEF = 1; // Default signal handling
-        const SIGHUP = 1 << 1;
-        const SIGINT = 1 << 2;
-        const SIGQUIT = 1 << 3;
-        const SIGILL = 1 << 4;
-        const SIGTRAP = 1 << 5;
-        const SIGABRT = 1 << 6;
-        const SIGBUS = 1 << 7;
-        const SIGFPE = 1 << 8;
-        const SIGKILL = 1 << 9;
-        const SIGUSR1 = 1 << 10;
-        const SIGSEGV = 1 << 11;
-        const SIGUSR2 = 1 << 12;
-        const SIGPIPE = 1 << 13;
-        const SIGALRM = 1 << 14;
-        const SIGTERM = 1 << 15;
-        const SIGSTKFLT = 1 << 16;
-        const SIGCHLD = 1 << 17;
-        const SIGCONT = 1 << 18;
-        const SIGSTOP = 1 << 19;
-        const SIGTSTP = 1 << 20;
-        const SIGTTIN = 1 << 21;
-        const SIGTTOU = 1 << 22;
-        const SIGURG = 1 << 23;
-        const SIGXCPU = 1 << 24;
-        const SIGXFSZ = 1 << 25;
-        const SIGVTALRM = 1 << 26;
-        const SIGPROF = 1 << 27;
-        const SIGWINCH = 1 << 28;
-        const SIGIO = 1 << 29;
-        const SIGPWR = 1 << 30;
-        const SIGSYS = 1 << 31;
+pub fn thread_create(entry: usize, arg: usize) -> isize {
+    sys_thread_create(entry, arg)
+}
+pub fn gettid() -> isize {
+    sys_gettid()
+}
+pub fn waittid(tid: usize) -> isize {
+    loop {
+        match sys_waittid(tid) {
+            -2 => {
+                yield_();
+            }
+            exit_code => return exit_code,
+        }
     }
 }
 
-pub fn kill(pid: usize, signal: i32) -> isize {
-    sys_kill(pid, signal)
+pub fn mutex_create() -> isize {
+    sys_mutex_create(false)
+}
+pub fn mutex_blocking_create() -> isize {
+    sys_mutex_create(true)
+}
+pub fn mutex_lock(mutex_id: usize) {
+    sys_mutex_lock(mutex_id);
+}
+pub fn mutex_unlock(mutex_id: usize) {
+    sys_mutex_unlock(mutex_id);
+}
+pub fn semaphore_create(res_count: usize) -> isize {
+    sys_semaphore_create(res_count)
+}
+pub fn semaphore_up(sem_id: usize) {
+    sys_semaphore_up(sem_id);
+}
+pub fn semaphore_down(sem_id: usize) {
+    sys_semaphore_down(sem_id);
+}
+pub fn condvar_create() -> isize {
+    sys_condvar_create(0)
+}
+pub fn condvar_signal(condvar_id: usize) {
+    sys_condvar_signal(condvar_id);
+}
+pub fn condvar_wait(condvar_id: usize, mutex_id: usize) {
+    sys_condvar_wait(condvar_id, mutex_id);
 }
 
-pub fn sigaction(signum: i32, action: *const SignalAction, old_action: *const SignalAction) -> isize {
-    sys_sigaction(signum, action, old_action)
+#[macro_export]
+macro_rules! vstore {
+    ($var_ref: expr, $value: expr) => {
+        unsafe { core::intrinsics::volatile_store($var_ref as *const _ as _, $value) }
+    };
 }
 
-pub fn sigprocmask(mask: u32) -> isize {
-    sys_sigprocmask(mask)
+#[macro_export]
+macro_rules! vload {
+    ($var_ref: expr) => {
+        unsafe { core::intrinsics::volatile_load($var_ref as *const _ as _) }
+    };
 }
 
-pub fn sigreturn() -> isize {
-    sys_sigreturn()
+#[macro_export]
+macro_rules! memory_fence {
+    () => {
+        core::sync::atomic::fence(core::sync::atomic::Ordering::SeqCst)
+    };
 }

user/src/syscall.rs

@@ -1,7 +1,3 @@
-use core::arch::asm;
-
-use crate::SignalAction;
-
 const SYSCALL_DUP: usize = 24;
 const SYSCALL_OPEN: usize = 56;
 const SYSCALL_CLOSE: usize = 57;
@@ -9,21 +5,31 @@ const SYSCALL_PIPE: usize = 59;
 const SYSCALL_READ: usize = 63;
 const SYSCALL_WRITE: usize = 64;
 const SYSCALL_EXIT: usize = 93;
+const SYSCALL_SLEEP: usize = 101;
 const SYSCALL_YIELD: usize = 124;
 const SYSCALL_KILL: usize = 129;
-const SYSCALL_SIGACTION: usize = 134;
-const SYSCALL_SIGPROCMASK: usize = 135;
-const SYSCALL_SIGRETURN: usize = 139;
 const SYSCALL_GET_TIME: usize = 169;
 const SYSCALL_GETPID: usize = 172;
 const SYSCALL_FORK: usize = 220;
 const SYSCALL_EXEC: usize = 221;
 const SYSCALL_WAITPID: usize = 260;
+const SYSCALL_THREAD_CREATE: usize = 1000;
+const SYSCALL_GETTID: usize = 1001;
+const SYSCALL_WAITTID: usize = 1002;
+const SYSCALL_MUTEX_CREATE: usize = 1010;
+const SYSCALL_MUTEX_LOCK: usize = 1011;
+const SYSCALL_MUTEX_UNLOCK: usize = 1012;
+const SYSCALL_SEMAPHORE_CREATE: usize = 1020;
+const SYSCALL_SEMAPHORE_UP: usize = 1021;
+const SYSCALL_SEMAPHORE_DOWN: usize = 1022;
+const SYSCALL_CONDVAR_CREATE: usize = 1030;
+const SYSCALL_CONDVAR_SIGNAL: usize = 1031;
+const SYSCALL_CONDVAR_WAIT: usize = 1032;
 
 fn syscall(id: usize, args: [usize; 3]) -> isize {
     let mut ret: isize;
     unsafe {
-        asm!(
+        core::arch::asm!(
             "ecall",
             inlateout("x10") args[0] => ret,
             in("x11") args[1],
@@ -66,6 +72,10 @@ pub fn sys_exit(exit_code: i32) -> ! {
     panic!("sys_exit never returns!");
 }
 
+pub fn sys_sleep(sleep_ms: usize) -> isize {
+    syscall(SYSCALL_SLEEP, [sleep_ms, 0, 0])
+}
+
 pub fn sys_yield() -> isize {
     syscall(SYSCALL_YIELD, [0, 0, 0])
 }
@@ -97,14 +107,50 @@ pub fn sys_waitpid(pid: isize, exit_code: *mut i32) -> isize {
     syscall(SYSCALL_WAITPID, [pid as usize, exit_code as usize, 0])
 }
 
-pub fn sys_sigaction(signum: i32, action: *const SignalAction, old_action: *const SignalAction) -> isize {
-    syscall(SYSCALL_SIGACTION, [signum as usize , action as usize, old_action as usize])
+pub fn sys_thread_create(entry: usize, arg: usize) -> isize {
+    syscall(SYSCALL_THREAD_CREATE, [entry, arg, 0])
+}
+
+pub fn sys_gettid() -> isize {
+    syscall(SYSCALL_GETTID, [0; 3])
+}
+
+pub fn sys_waittid(tid: usize) -> isize {
+    syscall(SYSCALL_WAITTID, [tid, 0, 0])
+}
+
+pub fn sys_mutex_create(blocking: bool) -> isize {
+    syscall(SYSCALL_MUTEX_CREATE, [blocking as usize, 0, 0])
+}
+
+pub fn sys_mutex_lock(id: usize) -> isize {
+    syscall(SYSCALL_MUTEX_LOCK, [id, 0, 0])
+}
+
+pub fn sys_mutex_unlock(id: usize) -> isize {
+    syscall(SYSCALL_MUTEX_UNLOCK, [id, 0, 0])
+}
+
+pub fn sys_semaphore_create(res_count: usize) -> isize {
+    syscall(SYSCALL_SEMAPHORE_CREATE, [res_count, 0, 0])
+}
+
+pub fn sys_semaphore_up(sem_id: usize) -> isize {
+    syscall(SYSCALL_SEMAPHORE_UP, [sem_id, 0, 0])
+}
+
+pub fn sys_semaphore_down(sem_id: usize) -> isize {
+    syscall(SYSCALL_SEMAPHORE_DOWN, [sem_id, 0, 0])
+}
+
+pub fn sys_condvar_create(_arg: usize) -> isize {
+    syscall(SYSCALL_CONDVAR_CREATE, [_arg, 0, 0])
 }
 
-pub fn sys_sigprocmask(mask: u32) -> isize {
-    syscall(SYSCALL_SIGPROCMASK, [mask as usize, 0, 0])
+pub fn sys_condvar_signal(condvar_id: usize) -> isize {
+    syscall(SYSCALL_CONDVAR_SIGNAL, [condvar_id, 0, 0])
 }
 
-pub fn sys_sigreturn() -> isize {
-    syscall(SYSCALL_SIGRETURN, [0, 0, 0])
+pub fn sys_condvar_wait(condvar_id: usize, mutex_id: usize) -> isize {
+    syscall(SYSCALL_CONDVAR_WAIT, [condvar_id, mutex_id, 0])
 }