Add SCX_LAVD scheduler

Dockerfile

@@ -35,6 +35,7 @@ RUN apt-get install -y \
     imagemagick \
     libdw-dev \
     libelf-dev \
+    dwarves \
     debhelper \
     device-tree-compiler \
     libssl-dev:arm64 \

README.md

@@ -113,7 +113,7 @@ For the kernel:
 sudo dpkg --add-architecture arm64
 sudo apt update
 sudo apt install git build-essential crossbuild-essential-arm64 bc bison flex \
-    imagemagick libssl-dev libdw-dev libelf-dev debhelper libssl-dev:arm64 rsync
+    imagemagick libssl-dev libdw-dev libelf-dev dwarves debhelper libssl-dev:arm64 rsync
 ```
 
 For assembling disk images — debos, bmaptool, and zeekstd all need to be installed from source:

build-kernel-mainline.sh

@@ -12,6 +12,19 @@
 
 set -e
 
+# pahole generates BTF; if it's missing/too old, olddefconfig silently drops
+# CONFIG_DEBUG_INFO_BTF and CONFIG_SCHED_CLASS_EXT (sched_ext). Fail loudly instead.
+if ! command -v pahole >/dev/null 2>&1; then
+	echo "ERROR: pahole not found. Install 'dwarves' in the build environment." >&2
+	exit 1
+fi
+_pv=$(pahole --version 2>/dev/null | sed 's/^v//')
+_pmaj=${_pv%%.*}; _pmin=${_pv#*.}; _pmin=${_pmin%%.*}
+if [ "${_pmaj:-0}" -lt 1 ] || { [ "${_pmaj:-0}" -eq 1 ] && [ "${_pmin:-0}" -lt 22 ]; }; then
+	echo "ERROR: pahole $_pv is too old (need >= 1.22 for BTF)." >&2
+	exit 1
+fi
+
 if [ -d "$LINUX_DIR" ]; then
 	if [ x"$KEEP_SRC" = x"update" ]; then
 		pushd "$LINUX_DIR"

configs/minconfig-mainline

@@ -25,6 +25,7 @@ CONFIG_CGROUP_PERF=y
 CONFIG_CGROUP_BPF=y
 CONFIG_USER_NS=y
 CONFIG_SCHED_AUTOGROUP=y
+CONFIG_SCHED_CLASS_EXT=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_PROFILING=y
@@ -787,11 +788,12 @@ CONFIG_PRINTK_TIME=y
 CONFIG_DYNAMIC_DEBUG=y
 CONFIG_DEBUG_KERNEL=y
 CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
-CONFIG_DEBUG_INFO_REDUCED=y
+CONFIG_DEBUG_INFO_BTF=y
 CONFIG_MAGIC_SYSRQ=y
 CONFIG_DEBUG_FS=y
 CONFIG_FUNCTION_TRACER=y
 CONFIG_FUNCTION_GRAPH_RETVAL=y
+CONFIG_FTRACE_SYSCALLS=y
 CONFIG_CORESIGHT=m
 CONFIG_CORESIGHT_LINK_AND_SINK_TMC=m
 CONFIG_CORESIGHT_CATU=m

debian-rk3576-ospack.yaml

@@ -246,6 +246,7 @@ actions:
       - libavformat-extra
       - lpac
       - mesa-teflon-delegate
+      - scx-lavd
 
   - action: overlay
     description: Overlay Kodi Chromium kiosk launcher

overlays/configs/systemd/system/multi-user.target.wants/scx-lavd.service

@@ -0,0 +1 @@
+/etc/systemd/system/scx-lavd.service