From 816e9dd752f18f2258fdd50128d36c277eeb5ff4 Mon Sep 17 00:00:00 2001
From: Benjamin Drung <bdrung@ubuntu.com>
Date: Fri, 11 Aug 2023 21:10:23 +0200
Subject: [PATCH] Use dracut-install in manual_add_modules

I sprinkled mkinitramfs with "date -Ins" to see where most time is
spent. I ran the [1] test case in a chroot on my laptop. mkinitramfs
took 18.3 seconds. The most time consuming parts:

* 10.13 s (51.4%) auto_add_modules
* 7.20 s (36.5%) run_scripts_optional /usr/share/initramfs-tools/hooks
* 1.27 s (6.4%) final { cat; cpio; cpio|compress } > $outfile

The remaining 1.11 seconds are spread over the remaining parts.

Following hooks in /usr/share/initramfs-tools/hooks took the longest:

* 4.56s (63.3%) framebuffer
* 0.87s (12.1%) plymouth
* 0.81s (11.3%) cryptroot
* 0.23s (3.2%) lvm2
* 0.18s (2.5%) udev
* 0.17s (2.4%) mdadm

The remaining 0.38 seconds are spread over the remaining dozen of hooks.

The framebuffer hook just calls copy_modules_dir and manual_add_modules
multiple times. auto_add_modules calls copy_modules_dir multiple times
and manual_add_modules. copy_modules_dir calls find and then
manual_add_modules.

So most time will be spent in manual_add_modules. This function calls
modprobe on the modules, copies the modules, and add_firmware on the
firmwares from a "modinfo -F firmware" call.

Replacing manual_add_modules by a call to /usr/lib/dracut/dracut-install
speeds up the initramfs building significantly. In the chroot on my
laptop the mkinitramfs execution reduces from 18.3 seconds to 11.0 (40%
reduction).

[1] schroot-wrapper -c mantic -u root --ppa bdrung/ppa -p \
linux-image-generic,initramfs-tools,zstd,busybox-initramfs,cryptsetup-initramfs,isc-dhcp-client,kbd,lvm2,mdadm,ntfs-3g,plymouth,plymouth-theme-spinner

LP: #2031185
Signed-off-by: Benjamin Drung <bdrung@ubuntu.com>
---
 debian/control |  2 +-
 hook-functions | 42 +++++++-----------------------------------
 2 files changed, 8 insertions(+), 36 deletions(-)

diff --git a/debian/control b/debian/control
index 1d9a5d4..200ea67 100644
--- a/debian/control
+++ b/debian/control
@@ -29,7 +29,7 @@ Package: initramfs-tools-core
 Architecture: all
 Multi-Arch: foreign
 Recommends: zstd
-Depends: ${busybox:Depends}, initramfs-tools-bin (= ${binary:Version}), klibc-utils (>= 2.0.4-8~), cpio (>= 2.12), kmod, udev, coreutils (>= 8.24), logsave | e2fsprogs (<< 1.45.3-1~), ${misc:Depends}
+Depends: ${busybox:Depends}, initramfs-tools-bin (= ${binary:Version}), dracut-core, klibc-utils (>= 2.0.4-8~), cpio (>= 2.12), kmod, udev, coreutils (>= 8.24), logsave | e2fsprogs (<< 1.45.3-1~), ${misc:Depends}
 Suggests: bash-completion
 Breaks: initramfs-tools (<< 0.121~), ${busybox:Breaks}
 Replaces: initramfs-tools (<< 0.121~)
diff --git a/hook-functions b/hook-functions
index fee8aab..a642b1f 100644
--- a/hook-functions
+++ b/hook-functions
@@ -85,47 +85,19 @@ add_firmware()
 # Add dependent modules + eventual firmware
 manual_add_modules()
 {
-	local prefix kmod options firmware
+	local dracut_verbose
 
 	if [ $# -eq 0 ]; then
 		return
 	fi
 
-	# modprobe --ignore-install inhibits processing of 'install'
-	# configuration lines, so that instead we will see 'insmod
-	# module.ko' as we want.  However it also means that 'softdep'
-	# configuration lines and embedded softdep information is not
-	# processed.  So we run twice, with and without this option.
-	# shellcheck disable=SC2034
-	{ /sbin/modprobe --all --set-version="${version?}" --ignore-install --quiet --show-depends "$@";
-	  /sbin/modprobe --all --set-version="${version}" --quiet --show-depends "$@"; } |
-	while read -r prefix kmod options ; do
-		if [ "${prefix}" != "insmod" ]; then
-			continue
-		fi
+	if [ "${verbose?}" = "y" ]; then
+		dracut_verbose=-v
+	fi
 
-		copy_file module "${kmod}" || continue
-
-		# Add required firmware
-		for firmware in $(modinfo -k "${version}" -F firmware "${kmod}"); do
-			# Only print warning for missing fw of loaded module
-			# or forced loaded module
-			if ! add_firmware "$firmware"; then
-				# Only warn about missing firmware if
-				# /proc/modules exists
-				if [ ! -e /proc/modules ] ; then
-					continue
-				fi
-
-				kmod_modname="${kmod##*/}"
-				kmod_modname="${kmod_modname%%.*}"
-				if grep -q "^$kmod_modname\\>" /proc/modules "${CONFDIR}/modules"; then
-					echo "W: Possible missing firmware /lib/firmware/${firmware} for module ${kmod_modname}" >&2
-				fi
-				continue
-			fi
-		done
-	done
+	/usr/lib/dracut/dracut-install -D "$DESTDIR" --kerneldir "/lib/modules/${version?}" \
+		--firmwaredirs "/lib/firmware/updates/${version?}:/lib/firmware/updates:/lib/firmware/${version?}:/lib/firmware" \
+		${dracut_verbose-} -o -m "$@"
 }
 
 # manual_add_modules() takes care of adding firmware for things that were built
-- 
2.39.2