build: switch c scheds to make

.github/include/ci.py

@@ -227,7 +227,11 @@ async def run_build():
     """Build all targets."""
     print("Running build...", flush=True)
 
+    print("Building C schedulers...", flush=True)
+    await run_command(["make", "all"], no_capture=True)
+    print("Building Rust schedulers...", flush=True)
     await run_command(["cargo", "build", "--all-targets", "--locked"], no_capture=True)
+
     print("✓ Build completed successfully", flush=True)
 
 

.github/include/flake.nix

@@ -94,6 +94,7 @@
               buildInputs = with pkgs; [
                 bash
                 binutils
+                bpftools
                 clang
                 coreutils
                 elfutils
@@ -102,6 +103,7 @@
                 glibc
                 gnumake
                 jq
+                libbpf-git
                 libseccomp
                 pkg-config
                 protobuf
@@ -170,6 +172,7 @@
                 bash
                 binutils
                 black
+                bpftools
                 clang
                 coreutils
                 gcc
@@ -179,6 +182,7 @@
                 gnused
                 isort
                 jq
+                libbpf-git
                 libseccomp.lib
                 llvmPackages.libclang
                 llvmPackages.libllvm

.gitignore

@@ -2,6 +2,7 @@ libbpf/
 *.gitignore
 PKGBUILD
 target
+build/
 *.swp
 .cache/
 .vscode/

INSTALL.md

@@ -38,22 +38,23 @@ $ sudo reboot
 #### Setting up Dev Environment
 
 ```
-$ sudo apt install -y build-essential meson cmake cargo rustc clang llvm pkg-config libelf-dev protobuf-compiler libseccomp-dev
+$ sudo apt install -y build-essential cmake cargo rustc clang llvm pkg-config libelf-dev protobuf-compiler libseccomp-dev
 ```
 
 #### Build the scx schedulers from source
 
 ```
 $ git clone https://github.com/sched-ext/scx.git
 $ cd scx
-$ meson setup build
-$ meson compile -C build
+$ make all                    # Build C schedulers
+$ cargo build --release       # Build Rust schedulers
 ```
 
 #### Install the scx schedulers from source
 
 ```
-$ meson install -C build
+$ make install INSTALL_DIR=~/bin                                        # Install C schedulers
+$ ls -d scheds/rust/scx_* | xargs -I{} cargo install --path {}          # Install Rust schedulers
 ```
 
 ## Arch Linux
@@ -67,7 +68,7 @@ sudo pacman -S scx-scheds
 In addition to the packages from the previous step, install the following.
 
 ```
-$ sudo pacman -Sy meson cargo bpf pahole
+$ sudo pacman -Sy cargo bpf pahole
 ```
 
 ## Gentoo Linux

Makefile

@@ -0,0 +1,112 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (c) 2025 Meta Platforms, Inc. and affiliates.
+
+# Always require out-of-source builds - default to O=build if not specified
+ifeq ("$(origin O)", "command line")
+  KBUILD_OUTPUT := $(abspath $(O))
+else
+  KBUILD_OUTPUT := $(CURDIR)/build
+endif
+
+# Always redirect to out-of-tree build directory unless we're already there
+ifneq ($(KBUILD_OUTPUT), $(CURDIR))
+# Only redirect if ROOT_SRC_DIR is not set (i.e., we're not already redirected)
+ifeq ($(ROOT_SRC_DIR),)
+
+PHONY += _all $(MAKECMDGOALS) sub-make
+
+$(filter-out _all sub-make,$(MAKECMDGOALS)) _all: sub-make
+	@:
+
+sub-make:
+	@mkdir -p $(KBUILD_OUTPUT)
+	@$(MAKE) --no-print-directory -C $(KBUILD_OUTPUT) -f $(CURDIR)/Makefile \
+		ROOT_SRC_DIR=$(CURDIR) \
+		LIB_OBJ_DIR=$(KBUILD_OUTPUT)/lib SCHED_OBJ_DIR=$(KBUILD_OUTPUT)/scheds/c \
+		$(MAKECMDGOALS)
+
+.PHONY: $(PHONY)
+
+# Skip the rest of the makefile when redirecting
+skip-makefile := 1
+endif
+endif
+
+ifeq ($(skip-makefile),)
+
+export BPF_CLANG ?= clang
+export BPFTOOL ?= bpftool
+
+ARCH := $(shell uname -m)
+ifeq ($(ARCH),x86_64)
+	TARGET_ARCH := x86
+else ifeq ($(ARCH),aarch64)
+	TARGET_ARCH := arm64
+else ifeq ($(ARCH),s390x)
+	TARGET_ARCH := s390
+else
+	TARGET_ARCH := $(ARCH)
+endif
+
+ENDIAN ?= $(shell printf '\1\0' | od -An -t x2 | awk '{print ($$1=="0001"?"little":"big")}')
+
+LIBBPF_CFLAGS := $(shell pkg-config --cflags libbpf)
+LIBBPF_LIBS := $(shell pkg-config --libs libbpf)
+
+export BPF_CFLAGS := -g -O2 -Wall -Wno-compare-distinct-pointer-types \
+	-D__TARGET_ARCH_$(TARGET_ARCH) -mcpu=v3 -m$(ENDIAN)-endian
+
+# ROOT_SRC_DIR is set by the top-level make call for out-of-source builds
+export ROOT_SRC_DIR ?= $(CURDIR)
+export BPF_INCLUDES := -I$(ROOT_SRC_DIR)/scheds/include \
+	-I$(ROOT_SRC_DIR)/scheds/include/arch/$(TARGET_ARCH) \
+	-I$(ROOT_SRC_DIR)/scheds/include/bpf-compat \
+	-I$(ROOT_SRC_DIR)/scheds/include/lib \
+	$(LIBBPF_CFLAGS)
+
+export CFLAGS := -std=gnu11 -I$(ROOT_SRC_DIR)/scheds/include -I$(SCHED_OBJ_DIR) $(LIBBPF_CFLAGS)
+
+export LIBBPF_DEPS := $(LIBBPF_LIBS) -lelf -lz -lzstd
+export THREAD_DEPS := -lpthread
+
+export OBJ_DIR := $(CURDIR)
+ifeq ($(LIB_OBJ_DIR),)
+  export LIB_OBJ_DIR := $(ROOT_SRC_DIR)/lib
+endif
+ifeq ($(SCHED_OBJ_DIR),)
+  export SCHED_OBJ_DIR := $(ROOT_SRC_DIR)/scheds/c
+endif
+
+# Scheduler lists for convenience targets
+C_SCHEDS := scx_simple scx_qmap scx_central scx_userland scx_nest scx_flatcg scx_pair scx_prev
+C_SCHEDS_LIB := scx_sdt
+
+all: lib scheds-c
+
+# Individual scheduler targets
+$(C_SCHEDS) $(C_SCHEDS_LIB): lib
+	@mkdir -p $(SCHED_OBJ_DIR)
+	@$(MAKE) -C $(ROOT_SRC_DIR)/scheds/c SRC_DIR=$(ROOT_SRC_DIR)/scheds/c $@
+
+$(LIB_OBJ_DIR) $(SCHED_OBJ_DIR):
+	@mkdir -p $@
+
+lib:
+	@mkdir -p $(LIB_OBJ_DIR)
+	@$(MAKE) -C $(ROOT_SRC_DIR)/lib SRC_DIR=$(ROOT_SRC_DIR)/lib
+
+scheds-c: lib
+	@mkdir -p $(SCHED_OBJ_DIR)
+	@$(MAKE) -C $(ROOT_SRC_DIR)/scheds/c SRC_DIR=$(ROOT_SRC_DIR)/scheds/c
+
+clean:
+	$(MAKE) -C $(ROOT_SRC_DIR)/lib clean
+	$(MAKE) -C $(ROOT_SRC_DIR)/scheds/c clean
+
+install: all
+	$(MAKE) -C $(ROOT_SRC_DIR)/scheds/c install
+
+.PHONY: all lib scheds-c clean install $(C_SCHEDS) $(C_SCHEDS_LIB)
+
+endif  # End of ifeq ($(skip-makefile),)