main/postmarketos-mkinitfs: enable profiling with bootchart (!852)

If (a) the kernel command line parameters include PMOS_BOOTCHART2 and
(b) /sbin/bootchartd exists (i.e., the bootchart2 package has been
installed), run /sbin/bootchartd instead of /sbin/init.

main/postmarketos-mkinitfs/APKBUILD

@@ -1,6 +1,6 @@
 pkgname=postmarketos-mkinitfs
 pkgver=0.8.0
-pkgrel=1
+pkgrel=2
 pkgdesc="Tool to generate initramfs images for postmarketOS"
 url="https://postmarketos.org"
 # multipath-tools: kpartx
@@ -23,6 +23,6 @@ package() {
 		"$pkgdir/sbin/mkinitfs"
 	mkdir -p "$pkgdir/etc/postmarketos-mkinitfs/hooks/"
 }
-sha512sums="8be7f29394f8cd4e1c4b93f018f6314350f7e37e20d242c97284c1b112a106f882318a101bc0c70b391590b969023901580c677ee9f869850e90e69171a44e80  init.sh.in
+sha512sums="1d49db8a48ad513cc548b8a0ea23cc64518e71c93863155b4e9d2271fb46090506331c03d6955d693c8568c248ecc76b218efe4a6f6bba57c41c5f6d775dc61b  init.sh.in
-44571b62e4d326355fa7d96add9a9115a89db3b6ce12c17aa4b0d5bd02d63d5b5d3152305af18795938bc9479d37b44e9a14268efa28a8c114c77ed498a7d65b  init_functions.sh
+3bcec7b35ced7e87c301f71a892e54aa40983396e2ebaa3c8cbd84c91f711b3ca0e30fbc3104b1a1018ec1af51844ba90a63d380359b51db6242562d21776ed0  init_functions.sh
 3f918f8b5967b73e507c2ddf36dccc24fee98298f05ca23e22605400de95137f8877e09769616e7db388557c645fb45c03e1e6b5bab815ec9f853c318f0431f1  mkinitfs.sh"

main/postmarketos-mkinitfs/init.sh.in

@@ -44,6 +44,9 @@ unlock_root_partition
 resize_root_filesystem
 mount_root_partition
 
+init="/sbin/init"
+setup_bootchart2
+
 # Switch root
 killall telnetd mdev msm-fb-refresher 2>/dev/null
 umount /boot
@@ -53,7 +56,7 @@ umount /dev/pts
 umount /dev
 
 # shellcheck disable=SC2093
-exec switch_root /sysroot /sbin/init
+exec switch_root /sysroot "$init"
 
 echo "ERROR: switch_root failed!"
 echo "Looping forever. Install and use the debug-shell hook to debug this."

main/postmarketos-mkinitfs/init_functions.sh

@@ -374,7 +374,7 @@ start_udhcpd() {
 	udhcpd
 }
 
-setup_directfb_tslib(){
+setup_directfb_tslib() {
 	# Set up directfb and tslib
 	# Note: linux_input module is disabled since it will try to take over
 	# the touchscreen device from tslib (e.g. on the N900)
@@ -385,14 +385,14 @@ setup_directfb_tslib(){
 	fi
 }
 
-start_onscreen_keyboard(){
+start_onscreen_keyboard() {
 	setup_directfb_tslib
 	osk-sdl -n root -d "$partition" -c /etc/osk.conf -v > /osk-sdl.log 2>&1
 	unset DFBARGS
 	unset TSLIB_TSDEVICE
 }
 
-start_charging_mode(){
+start_charging_mode() {
 	# Check cmdline for charging mode
 	chargingmodes="
 		androidboot.mode=charger
@@ -465,6 +465,25 @@ setup_framebuffer() {
 	set_framebuffer_mode
 }
 
+setup_bootchart2() {
+	if grep -q PMOS_BOOTCHART2 /proc/cmdline; then
+		if [ -f "/sysroot/sbin/bootchartd" ]; then
+			# shellcheck disable=SC2034
+			init="/sbin/bootchartd"
+			echo "remounting /sysroot as rw for /sbin/bootchartd"
+			mount -o remount, rw /sysroot
+
+			# /dev/null may not exist at the first boot after
+			# the root filesystem has been created.
+			[ -c /sysroot/dev/null ] && return
+			echo "creating /sysroot/dev/null for /sbin/bootchartd"
+			mknod -m 666 "/sysroot/dev/null" c 1 3
+		else
+			echo "WARNING: bootchart2 is not installed."
+		fi
+	fi
+}
+
 loop_forever() {
 	while true; do
 		sleep 1