ci(xtask): add support for rftrace

.github/workflows/ci.yml

@@ -131,11 +131,11 @@ jobs:
         profile: [dev, release]
         include:
           - arch: x86_64
-            packages: qemu-system-x86 libcap-ng-dev libseccomp-dev
-            flags: --features pci-ids
+            packages: qemu-system-x86 libcap-ng-dev libseccomp-dev uftrace
+            flags: --features hermit/pci-ids
           - arch: aarch64
             packages: qemu-system-aarch64
-            flags: --features pci-ids
+            flags: --features hermit/pci-ids
           - arch: riscv64
             packages: qemu-system-misc
             flags: --no-default-features
@@ -157,6 +157,9 @@ jobs:
         run: |
           sudo apt-get update
           sudo apt-get install ${{ matrix.packages }}
+      - uses: dtolnay/rust-toolchain@nightly
+        with:
+          components: rust-src
       - uses: mkroening/rust-toolchain-toml@main
       - uses: mkroening/rust-toolchain-toml@main
         with:
@@ -185,6 +188,8 @@ jobs:
       - run: cargo xtask ci qemu --arch ${{ matrix.arch }} --profile ${{ matrix.profile }} ${{ matrix.flags }} --package rusty_demo --smp 4
         # https://github.com/hermit-os/kernel/issues/737
         if: ${{ matrix.arch != 'aarch64' }}
+      - run: cargo xtask ci qemu --arch ${{ matrix.arch }} --profile ${{ matrix.profile }} ${{ matrix.flags }} --package rftrace-example --virtiofsd
+        if: ${{ matrix.arch == 'x86_64' }}
       - run: cargo xtask ci qemu --arch ${{ matrix.arch }} --profile ${{ matrix.profile }} ${{ matrix.flags }} --package httpd --features ci,dhcpv4 --netdev virtio-net-pci
         if: ${{ matrix.arch != 'riscv64' }}
       - run: cargo xtask ci qemu --arch ${{ matrix.arch }} --profile ${{ matrix.profile }} ${{ matrix.flags }} --package httpd --features ci,dhcpv4 --netdev rtl8139 --features rtl8139

xtask/src/archive.rs

@@ -1,12 +1,10 @@
 use std::collections::HashSet;
-use std::env;
 use std::fmt::Write;
 use std::path::{Path, PathBuf};
 
-use anyhow::{anyhow, Result};
+use anyhow::Result;
 use goblin::archive::Archive as GoblinArchive;
 use goblin::elf64::header;
-use llvm_tools::LlvmTools;
 use xshell::cmd;
 
 pub struct Archive(PathBuf);
@@ -51,7 +49,7 @@ impl Archive {
 		};
 
 		let all_symbols = {
-			let nm = binutil("nm")?;
+			let nm = crate::binutil("nm")?;
 			let stdout = cmd!(sh, "{nm} --export-symbols {archive}").output()?.stdout;
 			String::from_utf8(stdout)?
 		};
@@ -75,7 +73,7 @@ impl Archive {
 		let rename_path = archive.with_extension("redefine-syms");
 		sh.write_file(&rename_path, symbol_renames)?;
 
-		let objcopy = binutil("objcopy")?;
+		let objcopy = crate::binutil("objcopy")?;
 		cmd!(sh, "{objcopy} --redefine-syms={rename_path} {archive}").run()?;
 
 		sh.remove_path(&rename_path)?;
@@ -88,7 +86,7 @@ impl Archive {
 		let archive = self.as_ref();
 		let file = file.as_ref();
 
-		let ar = binutil("ar")?;
+		let ar = crate::binutil("ar")?;
 		cmd!(sh, "{ar} qL {archive} {file}").run()?;
 
 		Ok(())
@@ -115,22 +113,3 @@ impl Archive {
 		Ok(())
 	}
 }
-
-fn binutil(name: &str) -> Result<PathBuf> {
-	let exe_suffix = env::consts::EXE_SUFFIX;
-	let exe = format!("llvm-{name}{exe_suffix}");
-
-	let path = LlvmTools::new()
-		.map_err(|err| match err {
-			llvm_tools::Error::NotFound => anyhow!(
-				"Could not find llvm-tools component\n\
-				\n\
-				Maybe the rustup component `llvm-tools` is missing? Install it through: `rustup component add llvm-tools`"
-			),
-			err => anyhow!("{err:?}"),
-		})?
-		.tool(&exe)
-		.ok_or_else(|| anyhow!("could not find {exe}"))?;
-
-	Ok(path)
-}

xtask/src/binutil.rs

@@ -0,0 +1,22 @@
+use std::path::PathBuf;
+
+use anyhow::{anyhow, Result};
+
+pub fn binutil(name: &str) -> Result<PathBuf> {
+	let exe_suffix = std::env::consts::EXE_SUFFIX;
+	let exe = format!("llvm-{name}{exe_suffix}");
+
+	let path = llvm_tools::LlvmTools::new()
+		.map_err(|err| match err {
+			llvm_tools::Error::NotFound => anyhow!(
+				"Could not find llvm-tools component\n\
+				\n\
+				Maybe the rustup component `llvm-tools` is missing? Install it through: `rustup component add llvm-tools`"
+			),
+			err => anyhow!("{err:?}"),
+		})?
+		.tool(&exe)
+		.ok_or_else(|| anyhow!("could not find {exe}"))?;
+
+	Ok(path)
+}

xtask/src/ci/build.rs

@@ -26,6 +26,15 @@ impl Build {
 
 		let sh = crate::sh()?;
 
+		let _push_env = if self.package.contains("rftrace") {
+			Some(sh.push_env(
+				"RUSTFLAGS",
+				"-Zinstrument-mcount -Cpasses=ee-instrument<post-inline>",
+			))
+		} else {
+			None
+		};
+
 		cmd!(sh, "cargo build --manifest-path ../Cargo.toml")
 			.args(self.cargo_build.artifact.arch.ci_cargo_args())
 			.cargo_build_args(&self.cargo_build)

xtask/src/ci/qemu.rs

@@ -1,9 +1,10 @@
 use std::io::{Read, Write};
 use std::net::{TcpStream, UdpSocket};
+use std::path::Path;
 use std::process::{Child, Command, ExitStatus};
 use std::str::from_utf8;
 use std::time::Duration;
-use std::{env, thread};
+use std::{env, fs, thread};
 
 use anyhow::{bail, ensure, Context, Result};
 use clap::{Args, ValueEnum};
@@ -63,6 +64,10 @@ impl Qemu {
 		let virtiofsd = self.virtiofsd.then(spawn_virtiofsd).transpose()?;
 		thread::sleep(Duration::from_millis(100));
 
+		if self.build.package.contains("rftrace") {
+			sh.create_dir("shared/tracedir")?;
+		}
+
 		let arch = self.build.cargo_build.artifact.arch.name();
 		let qemu = env::var_os("QEMU").unwrap_or_else(|| format!("qemu-system-{arch}").into());
 
@@ -109,6 +114,10 @@ impl Qemu {
 			assert!(status.success());
 		}
 
+		if self.build.package.contains("rftrace") {
+			check_rftrace(&self.build.image())?;
+		}
+
 		Ok(())
 	}
 
@@ -246,9 +255,9 @@ impl Qemu {
 fn spawn_virtiofsd() -> Result<KillChildOnDrop> {
 	let sh = crate::sh()?;
 
-	sh.create_dir("foo")?;
+	sh.create_dir("shared")?;
 
-	let cmd = cmd!(sh, "virtiofsd --socket-path=./vhostqemu --shared-dir ./foo --announce-submounts --sandbox none --seccomp none --inode-file-handles=never");
+	let cmd = cmd!(sh, "virtiofsd --socket-path=./vhostqemu --shared-dir ./shared --announce-submounts --sandbox none --seccomp none --inode-file-handles=never");
 
 	eprintln!("$ {cmd}");
 
@@ -332,6 +341,32 @@ fn test_mioudp() -> Result<()> {
 	Ok(())
 }
 
+fn check_rftrace(image: &Path) -> Result<()> {
+	let sh = crate::sh()?;
+	let image_name = image.file_name().unwrap().to_str().unwrap();
+
+	let nm = crate::binutil("nm")?;
+	let symbols = cmd!(sh, "{nm} --numeric-sort {image}").output()?.stdout;
+	sh.write_file(format!("shared/tracedir/{image_name}.sym"), symbols)?;
+
+	let replay = cmd!(
+		sh,
+		"uftrace replay --data=shared/tracedir --output-fields=tid"
+	)
+	.read()?;
+	eprintln!("[CI] replay: {replay}");
+
+	let expected = fs::read_to_string("xtask/src/ci/rftrace.snap")?;
+	if !replay.starts_with(&expected) {
+		eprintln!("[CI] expected: {expected}");
+		bail!("rftrace output does not match snapshot");
+	}
+
+	eprintln!("[CI] replay matches snapshot");
+
+	Ok(())
+}
+
 struct KillChildOnDrop(Child);
 
 impl Drop for KillChildOnDrop {

xtask/src/ci/rftrace.snap

@@ -0,0 +1,4 @@
+#   TID     FUNCTION
+ [     1] | rftrace_example::f1() {
+ [     1] |   rftrace_example::f2() {
+ [     1] |     rftrace_example::f3()

xtask/src/main.rs

@@ -3,6 +3,7 @@
 mod arch;
 mod archive;
 mod artifact;
+mod binutil;
 mod build;
 mod cargo_build;
 mod ci;
@@ -11,6 +12,7 @@ mod clippy;
 use std::path::Path;
 
 use anyhow::Result;
+pub(crate) use binutil::binutil;
 use clap::Parser;
 use xshell::Shell;