Merge #85 #86

85: Remove raw-cpuid dependency and use rdrand intrinsics r=phil-opp a=64

This reduces my compile times from scratch from about 215s to 160s.

86: Update integration tests to use new testing framework r=phil-opp a=phil-opp

Use `cargo xtest` and `bootimage runner` instead of the old `bootimage test` for testing. See https://os.phil-opp.com/testing/ for more information on the approach.

Co-authored-by: Matt Taylor <mstaveleytaylor@gmail.com>
Co-authored-by: Philipp Oppermann <dev@phil-opp.com>

.travis.yml

@@ -18,7 +18,7 @@ script:
   - cargo build
   - cargo test
   - cargo build --features deny-warnings
-  - bootimage test --manifest-path testing/Cargo.toml
+  - cd testing && cargo xtest && cd ..
   - cargo build --target i686-unknown-linux-gnu
   - cargo build --target thumbv7em-none-eabihf
 

Cargo.toml

@@ -34,9 +34,6 @@ array-init = "0.0.4"
 version = "0.2.2"
 default-features = false
 
-[target.'cfg(target_arch = "x86_64")'.dependencies]
-raw-cpuid = "6.1.0"
-
 [dependencies.ux]
 default-features = false
 version = "0.1.3"

azure-pipelines.yml

@@ -102,8 +102,9 @@ steps:
 - script: rustup component add llvm-tools-preview
   displayName: "Add llvm-tools-preview Rustup Component"
 
-- script: bootimage test --manifest-path testing/Cargo.toml
+- script: cargo xtest
   displayName: 'Integration Tests'
+  workingDirectory: 'testing'
 
 - script: rustup component add rustfmt
   displayName: 'Install Rustfmt'

src/instructions/random.rs

@@ -8,64 +8,77 @@ pub struct RdRand(());
 impl RdRand {
     /// Creates Some(RdRand) if RDRAND is supported, None otherwise
     pub fn new() -> Option<Self> {
-        let cpuid = raw_cpuid::CpuId::new();
-        let has_rdrand = match cpuid.get_feature_info() {
-            Some(finfo) => finfo.has_rdrand(),
-            None => false,
-        };
-
-        match has_rdrand {
-            true => Some(RdRand(())),
-            false => None,
+        // RDRAND support indicated by CPUID page 01h, ecx bit 30
+        // https://en.wikipedia.org/wiki/RdRand#Overview
+        let cpuid = unsafe { core::arch::x86_64::__cpuid(0x1) };
+        if cpuid.ecx & (1 << 30) != 0 {
+            Some(RdRand(()))
+        } else {
+            None
         }
     }
 
     /// Uniformly sampled u64.
     /// May fail in rare circumstances or heavy load.
     #[inline]
     pub fn get_u64(&self) -> Option<u64> {
-        let res: u64;
-        let ok: u8;
+        let mut res: u64 = 0;
         unsafe {
-            asm!("rdrand %rax; setc $1;"
-                : "={rax}"(res) "=r"(ok)
-                :: "flags" : "volatile");
-        }
-        match ok {
-            1 => Some(res),
-            _ => None,
+            match core::arch::x86_64::_rdrand64_step(&mut res) {
+                1 => Some(res),
+                x => {
+                    debug_assert_eq!(x, 0, "rdrand64 returned non-binary value");
+                    None
+                }
+            }
         }
     }
     /// Uniformly sampled u32.
     /// May fail in rare circumstances or heavy load.
     #[inline]
     pub fn get_u32(&self) -> Option<u32> {
-        let res: u32;
-        let ok: u8;
+        let mut res: u32 = 0;
         unsafe {
-            asm!("rdrand %eax; setc $1;"
-                : "={eax}"(res) "=r"(ok)
-                :: "flags" : "volatile");
-        }
-        match ok {
-            1 => Some(res),
-            _ => None,
+            match core::arch::x86_64::_rdrand32_step(&mut res) {
+                1 => Some(res),
+                x => {
+                    debug_assert_eq!(x, 0, "rdrand32 returned non-binary value");
+                    None
+                }
+            }
         }
     }
     /// Uniformly sampled u16.
     /// May fail in rare circumstances or heavy load.
     #[inline]
     pub fn get_u16(&self) -> Option<u16> {
-        let res: u16;
-        let ok: u8;
+        let mut res: u16 = 0;
         unsafe {
-            asm!("rdrand %ax; setc $1;"
-                : "={ax}"(res) "=r"(ok)
-                :: "flags" : "volatile");
+            match core::arch::x86_64::_rdrand16_step(&mut res) {
+                1 => Some(res),
+                x => {
+                    debug_assert_eq!(x, 0, "rdrand16 returned non-binary value");
+                    None
+                }
+            }
         }
-        match ok {
-            1 => Some(res),
-            _ => None,
+    }
+}
+
+#[cfg(all(test, target_arch = "x86_64"))]
+mod tests {
+    use super::*;
+
+    #[test]
+    pub fn test_rdrand() {
+        let rand = RdRand::new();
+        if is_x86_feature_detected!("rdrand") {
+            let rand = rand.unwrap();
+            assert!(rand.get_u16().is_some());
+            assert!(rand.get_u32().is_some());
+            assert!(rand.get_u64().is_some());
+        } else {
+            assert!(rand.is_none());
         }
     }
 }

testing/.cargo/config

@@ -0,0 +1,5 @@
+[build]
+target = "x86_64-bare-metal.json"
+
+[target.'cfg(target_os = "none")']
+runner = "bootimage runner"

testing/Cargo.toml

@@ -4,17 +4,33 @@ version = "0.1.0"
 authors = ["Philipp Oppermann <dev@phil-opp.com>"]
 edition = "2018"
 
+[[test]]
+name = "breakpoint_exception"
+harness = false
+
+[[test]]
+name = "port_read_write"
+harness = false
+
+[[test]]
+name = "double_fault_stack_overflow"
+harness = false
+
 [dependencies]
-bootloader = "0.5.3"
-uart_16550 = "0.1.0"
-spin = "0.4.8"
+bootloader = "0.6.4"
+uart_16550 = "0.2.0"
+spin = "0.5.0"
 
 [dependencies.x86_64]
 path = ".."
 
 [dependencies.lazy_static]
-version = "1.0"
+version = "1.3.0"
 features = ["spin_no_std"]
 
 [package.metadata.bootimage]
-default-target = "x86_64-bare-metal.json"
+test-args = [
+    "-device", "isa-debug-exit,iobase=0xf4,iosize=0x04", "-serial", "stdio",
+    "-display", "none"
+]
+test-success-exit-code = 33

testing/src/lib.rs

@@ -1,17 +1,56 @@
+#![cfg_attr(test, no_main)]
+#![feature(custom_test_frameworks)]
+#![test_runner(crate::test_runner)]
+#![reexport_test_harness_main = "test_main"]
 #![no_std]
 
-extern crate spin;
-extern crate uart_16550;
-extern crate x86_64;
-#[macro_use]
-extern crate lazy_static;
+use core::panic::PanicInfo;
 
+#[macro_use]
 pub mod serial;
 pub mod gdt;
+mod tests;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u32)]
+pub enum QemuExitCode {
+    Success = 0x10,
+    Failed = 0x11,
+}
+
+pub fn exit_qemu(exit_code: QemuExitCode) {
+    use x86_64::instructions::port::Port;
+
+    unsafe {
+        let mut port = Port::new(0xf4);
+        port.write(exit_code as u32);
+    }
+}
+
+pub fn test_runner(tests: &[&dyn Fn()]) {
+    serial_println!("Running {} tests", tests.len());
+    for test in tests {
+        test();
+    }
+    exit_qemu(QemuExitCode::Success);
+}
 
-use x86_64::instructions::port::Port;
+pub fn test_panic_handler(info: &PanicInfo) -> ! {
+    serial_println!("[failed]\n");
+    serial_println!("Error: {}\n", info);
+    exit_qemu(QemuExitCode::Failed);
+    loop {}
+}
+
+#[cfg(test)]
+#[no_mangle]
+pub extern "C" fn _start() -> ! {
+    test_main();
+    loop {}
+}
 
-pub unsafe fn exit_qemu() {
-    let mut port = Port::<u32>::new(0xf4);
-    port.write(0);
+#[cfg(test)]
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    test_panic_handler(info)
 }

testing/src/serial.rs

@@ -1,9 +1,10 @@
+use lazy_static::lazy_static;
 use spin::Mutex;
 use uart_16550::SerialPort;
 
 lazy_static! {
     pub static ref SERIAL1: Mutex<SerialPort> = {
-        let mut serial_port = SerialPort::new(0x3F8);
+        let mut serial_port = unsafe { SerialPort::new(0x3F8) };
         serial_port.init();
         Mutex::new(serial_port)
     };

testing/src/tests.rs

@@ -0,0 +1,6 @@
+#[test_case]
+fn example_test() {
+    serial_print!("example_test... ");
+    assert_eq!(0, 0);
+    serial_println!("[ok]");
+}

testing/tests/basic_boot.rs

@@ -0,0 +1,27 @@
+#![no_std]
+#![no_main]
+#![feature(custom_test_frameworks)]
+#![reexport_test_harness_main = "test_main"]
+#![test_runner(testing::test_runner)]
+
+use core::panic::PanicInfo;
+use testing::{serial_print, serial_println};
+
+#[no_mangle] // don't mangle the name of this function
+pub extern "C" fn _start() -> ! {
+    test_main();
+
+    loop {}
+}
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    testing::test_panic_handler(info)
+}
+
+#[test_case]
+fn basic_boot() {
+    serial_print!("basic_boot... ");
+    assert_eq!(0, 0);
+    serial_println!("[ok]");
+}