Always build eBPF; remove xtask

.cargo/config.toml

@@ -1,2 +0,0 @@
-[alias]
-xtask = "run --package xtask --"

Cargo.toml

@@ -1,7 +1,7 @@
 [workspace]
 resolver = "2"
-members = ["xtask", "{{project-name}}", "{{project-name}}-common", "{{project-name}}-ebpf"]
+members = ["{{project-name}}", "{{project-name}}-common", "{{project-name}}-ebpf"]
-default-members = ["xtask", "{{project-name}}", "{{project-name}}-common"]
+default-members = ["{{project-name}}", "{{project-name}}-common"]
 
 [workspace.dependencies]
 aya = { version = "0.13.0", default-features = false }

README.md

@@ -11,18 +11,21 @@
 
 ## Build & Run
 
-Use `cargo build`, `cargo check`, etc. as normal. Run your program with `xtask run`.
+Use `cargo build`, `cargo check`, etc. as normal. Run your program with:
+
+```shell
+cargo run --release --config 'target."cfg(all())".runner="sudo -E"'
+```
 
 Cargo build scripts are used to automatically build the eBPF correctly and include it in the
-program. When not using `xtask run`, eBPF code generation is skipped for a faster developer
+program.
-experience; this compromise necessitates the use of `xtask` to actually build the eBPF.
 
 ## Cross-compiling on macOS
 
 Cross compilation should work on both Intel and Apple Silicon Macs.
 
 ```shell
-AYA_BUILD_EBPF=true CC=${ARCH}-linux-musl-gcc cargo build --package {{project-name}} --release \
+CC=${ARCH}-linux-musl-gcc cargo build --package {{project-name}} --release \
   --target=${ARCH}-unknown-linux-musl \
   --config=target.${ARCH}-unknown-linux-musl.linker=\"${ARCH}-linux-musl-gcc\"
 ```

test.sh

@@ -68,9 +68,10 @@ case $OS in
   if [[ "$ARCH" == "arm64" ]]; then
     ARCH="aarch64"
   fi
-  AYA_BUILD_EBPF=true CC=${ARCH}-linux-musl-gcc cargo build --package "${CRATE_NAME}" --release \
+  TARGET=${ARCH}-unknown-linux-musl
-    --target="${ARCH}"-unknown-linux-musl \
+  CC=${ARCH}-linux-musl-gcc cargo build --package "${CRATE_NAME}" --release \
-    --config=target."${ARCH}"-unknown-linux-musl.linker=\""${ARCH}"-linux-musl-gcc\"
+    --target="${TARGET}" \
+    --config=target."${TARGET}".linker=\""${ARCH}"-linux-musl-gcc\"
   ;;
 "Linux")
   cargo +nightly fmt --all -- --check
@@ -85,7 +86,7 @@ case $OS in
 
   expect <<EOF
     set timeout 30        ;# Increase timeout if necessary
-    spawn cargo xtask run
+    spawn cargo run --release --config "target.\"cfg(all())\".runner=\"sudo -E\""
     expect {
       -re "Waiting for Ctrl-C.*" {
         send -- \003      ;# Send Ctrl-C

xtask/Cargo.toml

@@ -1,8 +0,0 @@
-[package]
-name = "xtask"
-version = "0.1.0"
-edition = "2021"
-
-[dependencies]
-anyhow = { workspace = true, default-features = true }
-clap = { workspace = true, default-features = true, features = ["derive"] }

xtask/src/lib.rs

@@ -1 +0,0 @@
-pub const AYA_BUILD_EBPF: &str = "AYA_BUILD_EBPF";

xtask/src/main.rs

@@ -1,23 +0,0 @@
-mod run;
-
-use anyhow::Result;
-use clap::Parser;
-
-#[derive(Debug, Parser)]
-pub struct Options {
-    #[clap(subcommand)]
-    command: Command,
-}
-
-#[derive(Debug, Parser)]
-enum Command {
-    Run(run::Options),
-}
-
-fn main() -> Result<()> {
-    let Options { command } = Parser::parse();
-
-    match command {
-        Command::Run(opts) => run::run(opts),
-    }
-}

xtask/src/run.rs

@@ -1,47 +0,0 @@
-use std::{ffi::OsString, process::Command};
-
-use anyhow::{bail, Context as _, Result};
-use clap::Parser;
-use xtask::AYA_BUILD_EBPF;
-
-#[derive(Debug, Parser)]
-pub struct Options {
-    /// Build and run the release target.
-    #[clap(long)]
-    release: bool,
-    /// The command used to wrap your application.
-    #[clap(short, long, default_value = "sudo -E")]
-    runner: String,
-    /// Arguments to pass to your application.
-    #[clap(global = true, last = true)]
-    run_args: Vec<OsString>,
-}
-
-/// Build and run the project.
-pub fn run(opts: Options) -> Result<()> {
-    let Options {
-        release,
-        runner,
-        run_args,
-    } = opts;
-
-    let mut cmd = Command::new("cargo");
-    cmd.env(AYA_BUILD_EBPF, "true");
-    cmd.args(["run", "--package", "{{project-name}}", "--config"]);
-    if release {
-        cmd.arg(format!("target.\"cfg(all())\".runner=\"{}\"", runner));
-        cmd.arg("--release");
-    } else {
-        cmd.arg(format!("target.\"cfg(all())\".runner=\"{}\"", runner));
-    }
-    if !run_args.is_empty() {
-        cmd.arg("--").args(run_args);
-    }
-    let status = cmd
-        .status()
-        .with_context(|| format!("failed to run {cmd:?}"))?;
-    if status.code() != Some(0) {
-        bail!("{cmd:?} failed: {status:?}")
-    }
-    Ok(())
-}

{{project-name}}-ebpf/Cargo.toml

@@ -11,7 +11,6 @@ aya-log-ebpf = { workspace = true }
 
 [build-dependencies]
 which = { workspace = true }
-xtask = { path = "../xtask" }
 
 [[bin]]
 name = "{{ project-name }}"

{{project-name}}-ebpf/build.rs

@@ -1,7 +1,4 @@
-use std::env;
-
 use which::which;
-use xtask::AYA_BUILD_EBPF;
 
 /// Building this crate has an undeclared dependency on the `bpf-linker` binary. This would be
 /// better expressed by [artifact-dependencies][bindeps] but issues such as
@@ -15,16 +12,6 @@ use xtask::AYA_BUILD_EBPF;
 ///
 /// [bindeps]: https://doc.rust-lang.org/nightly/cargo/reference/unstable.html?highlight=feature#artifact-dependencies
 fn main() {
-    println!("cargo:rerun-if-env-changed={}", AYA_BUILD_EBPF);
+    let bpf_linker = which("bpf-linker").unwrap();
-
+    println!("cargo:rerun-if-changed={}", bpf_linker.to_str().unwrap());
-    let build_ebpf = env::var(AYA_BUILD_EBPF)
-        .as_deref()
-        .map(str::parse)
-        .map(Result::unwrap)
-        .unwrap_or_default();
-
-    if build_ebpf {
-        let bpf_linker = which("bpf-linker").unwrap();
-        println!("cargo:rerun-if-changed={}", bpf_linker.to_str().unwrap());
-    }
 }

{{project-name}}-ebpf/rust-toolchain.toml

@@ -1,2 +1,3 @@
 [toolchain]
 channel = "nightly"
+components = ["rust-src"]

{{project-name}}/Cargo.toml

@@ -33,7 +33,6 @@ cargo_metadata = { workspace = true }
 # workflows with stable cargo; stable cargo outright refuses to load manifests that use unstable
 # features.
 {{project-name}}-ebpf = { path = "../{{project-name}}-ebpf" }
-xtask = { path = "../xtask" }
 
 [[bin]]
 name = "{{project-name}}"

{{project-name}}/build.rs

@@ -8,7 +8,6 @@ use std::{
 use cargo_metadata::{
     Artifact, CompilerMessage, Message, Metadata, MetadataCommand, Package, Target,
 };
-use xtask::AYA_BUILD_EBPF;
 
 /// This crate has a runtime dependency on artifacts produced by the `{{project-name}}-ebpf` crate.
 /// This would be better expressed as one or more [artifact-dependencies][bindeps] but issues such
@@ -20,32 +19,8 @@ use xtask::AYA_BUILD_EBPF;
 ///
 /// prevent their use for the time being.
 ///
-/// This file, along with the xtask crate, allows analysis tools such as `cargo check`, `cargo
-/// clippy`, and even `cargo build` to work as users expect. Prior to this file's existence, this
-/// crate's undeclared dependency on artifacts from `{{project-name}}-ebpf` would cause build (and
-/// `cargo check`, and `cargo clippy`) failures until the user ran certain other commands in the
-/// workspace. Conversely, those same tools (e.g. cargo test --no-run) would produce stale results
-/// if run naively because they'd make use of artifacts from a previous build of
-/// `{{project-name}}-ebpf`.
-///
-/// Note that this solution is imperfect: in particular it has to balance correctness with
-/// performance; an environment variable is used to replace true builds of `{{project-name}}-ebpf`
-/// with stubs to preserve the property that code generation and linking (in
-/// `{{project-name}}-ebpf`) do not occur on metadata-only actions such as `cargo check` or `cargo
-/// clippy` of this crate. This means that naively attempting to `cargo test --no-run` this crate
-/// will produce binaries that fail at runtime because the stubs are inadequate for actually running
-/// the tests.
-///
 /// [bindeps]: https://doc.rust-lang.org/nightly/cargo/reference/unstable.html?highlight=feature#artifact-dependencies
 fn main() {
-    println!("cargo:rerun-if-env-changed={}", AYA_BUILD_EBPF);
-
-    let build_ebpf = env::var(AYA_BUILD_EBPF)
-        .as_deref()
-        .map(str::parse)
-        .map(Result::unwrap)
-        .unwrap_or_default();
-
     let Metadata { packages, .. } = MetadataCommand::new().no_deps().exec().unwrap();
     let ebpf_package = packages
         .into_iter()
@@ -64,6 +39,9 @@ fn main() {
         panic!("unsupported endian={:?}", endian)
     };
 
+    // TODO(https://github.com/rust-lang/cargo/issues/4001): Make this `false` if we can determine
+    // we're in a check build.
+    let build_ebpf = true;
     if build_ebpf {
         let arch = env::var_os("CARGO_CFG_TARGET_ARCH").unwrap();
 
@@ -94,7 +72,7 @@ fn main() {
         cmd.env("CARGO_CFG_BPF_TARGET_ARCH", arch);
 
         // Workaround to make sure that the rust-toolchain.toml is respected.
-        for key in ["RUSTUP_TOOLCHAIN", "RUSTC"] {
+        for key in ["RUSTUP_TOOLCHAIN", "RUSTC", "RUSTC_WORKSPACE_WRAPPER"] {
             cmd.env_remove(key);
         }
         cmd.current_dir(ebpf_dir);