Merge pull request #24 from rex-rs/ci

 - tools/memcached_benchmark: format files with new rustfmt config
 - ci: add check rust formating github workflow
 - ci: use concurrency to cancel redundant in‑flight runs
 - {rex, samples}: format files with new rustfmt config
 - tree-wide/rustfmt: set imports_granularity to Module and group_imports to StdExternalCrate

Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>

Author: jinghao-jia

.github/workflows/meson.yml

@@ -1,4 +1,9 @@
 name: Meson Build and Test
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref_name }}
+  cancel-in-progress: true
+
 on:
   push:
     branches: [main, ci]

.github/workflows/nix.yml

@@ -1,4 +1,9 @@
 name: Meson Build and Test via nix
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref_name }}
+  cancel-in-progress: true
+
 on:
   push:
     branches: [main, ci]

.github/workflows/rustfmt.yml

@@ -0,0 +1,35 @@
+name: Formatting check
+
+on:
+  push:
+    branches: [main, ci]
+    paths-ignore:
+      - docs/**
+      - tools/**
+      - README.md
+  pull_request:
+    branches: [main]
+    paths-ignore:
+      - docs/**
+      - tools/**
+      - README.md
+
+jobs:
+  formatting:
+    if: github.repository == 'rex-rs/rex'
+    name: cargo fmt
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: switch rust nightly
+        run: |
+          rustup default nightly
+          rustup component add rustfmt
+      - name: formatting rex code
+        run: cargo fmt
+      - name: formatting samples code
+        run: |
+          for d in $(find ./samples -name Cargo.toml); do
+            echo "→ Processing $d"
+            cargo fmt --manifest-path $d --verbose --check
+          done

rex-macros/src/args.rs

@@ -2,7 +2,8 @@ use std::collections::HashMap;
 
 use proc_macro2::TokenStream;
 use proc_macro_error::abort;
-use syn::{parse_str, spanned::Spanned, Expr, ExprAssign, Lit, LitStr, Result};
+use syn::spanned::Spanned;
+use syn::{parse_str, Expr, ExprAssign, Lit, LitStr, Result};
 
 macro_rules! pop_string_args {
     ($self:expr, $key:expr) => {

rex-macros/src/lib.rs

@@ -6,14 +6,14 @@ mod tc;
 mod tracepoint;
 mod xdp;
 
-use proc_macro::TokenStream;
-use proc_macro_error::{abort, proc_macro_error};
-use quote::quote;
 use std::borrow::Cow;
-use syn::ItemStatic;
 
 use kprobe::KProbe;
 use perf_event::PerfEvent;
+use proc_macro::TokenStream;
+use proc_macro_error::{abort, proc_macro_error};
+use quote::quote;
+use syn::ItemStatic;
 use tc::SchedCls;
 use tracepoint::TracePoint;
 use xdp::Xdp;

rex/build.rs

@@ -1,11 +1,10 @@
 #![feature(exit_status_error)]
 
-use std::env;
-use std::fs;
 use std::io::Result;
 use std::path::Path;
 use std::process::Command;
 use std::string::String;
+use std::{env, fs};
 
 fn main() -> Result<()> {
     let out_dir = env::var("OUT_DIR").unwrap();

rex/rustfmt.toml

@@ -1,14 +1,14 @@
+// use crate::timekeeping::*;
+use core::intrinsics::unlikely;
+use core::mem::MaybeUninit;
+
 use crate::ffi;
 use crate::linux::bpf::bpf_map_type;
 use crate::linux::errno::EINVAL;
 use crate::map::*;
 use crate::per_cpu::{cpu_number, this_cpu_read};
 use crate::random32::bpf_user_rnd_u32;
 use crate::utils::{to_result, NoRef, Result};
-use core::mem::MaybeUninit;
-// use crate::timekeeping::*;
-
-use core::intrinsics::unlikely;
 
 macro_rules! termination_check {
     ($func:expr) => {{
@@ -445,5 +445,4 @@ macro_rules! base_helper_defs {
     };
 }
 
-pub(crate) use base_helper_defs;
-pub(crate) use termination_check;
+pub(crate) use {base_helper_defs, termination_check};

rex/src/base_helper.rs

@@ -1,6 +1,4 @@
-use core::ffi::c_uchar;
-
-use core::ffi::c_int;
+use core::ffi::{c_int, c_uchar};
 
 use crate::ffi;
 

rex/src/debug.rs

@@ -1,9 +1,8 @@
 use crate::bindings::uapi::linux::bpf::{bpf_map_type, BPF_PROG_TYPE_KPROBE};
-use crate::ffi;
 use crate::prog_type::rex_prog;
 use crate::pt_regs::PtRegs;
 use crate::task_struct::TaskStruct;
-use crate::Result;
+use crate::{ffi, Result};
 
 /// First 3 fields should always be rtti, prog_fn, and name
 ///