diff mbox series

[wrynose,6/7] initramfs-framework: avoid processes when parsing cmdline

Message ID 20261016031833.708267-1-wenwfu@qti.qualcomm.com
State Rejected
Delegated to: Yoann Congal
Headers show
Series [wrynose,1/7] initramfs-framework: add opt-in root-only udev trigger | expand

Commit Message

Wenwen Fu Oct. 16, 2026, 3:18 a.m. UTC 
Use POSIX shell parameter expansion instead of external cut and sed
while parsing kernel command-line parameters. This keeps the parser
compatible with /bin/sh implementations that do not support Bash-style
pattern substitution while avoiding per-parameter processes.

On QEMU, cmdline parsing decreased from 1.381871 s to 0.056985 s,
a 95.9% reduction.

Tested with dash and BusyBox sh syntax checks and QEMU.

AI-Generated: OpenAI Codex
Signed-off-by: Wenwen Fu <wenwfu@qti.qualcomm.com>
Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit b560c7527a66b8fa90817a92b16b323493fb394d)
---
 .../initrdscripts/initramfs-framework/init        | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)
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Patch

diff --git a/meta/recipes-core/initrdscripts/initramfs-framework/init b/meta/recipes-core/initrdscripts/initramfs-framework/init
index e3bf97bba9..e03685175f 100755
--- a/meta/recipes-core/initrdscripts/initramfs-framework/init
+++ b/meta/recipes-core/initrdscripts/initramfs-framework/init
@@ -100,13 +100,20 @@  for p in `cat /proc/cmdline`; do
 		continue
 	fi
 
-	opt=`echo $p | cut -d'=' -f1`
-	opt=`echo $opt | sed -e 'y/.-/__/'`
-	if [ "`echo $p | cut -d'=' -f1`" = "$p" ]; then
+	key=${p%%=*}
+	opt=$key
+	while :; do
+		case "$opt" in
+			*.*) opt=${opt%%.*}_${opt#*.} ;;
+			*-*) opt=${opt%%-*}_${opt#*-} ;;
+			*) break ;;
+		esac
+	done
+	if [ "$key" = "$p" ]; then
 		# opt parameter
 		eval "bootparam_${opt}=true"
 	else
-		value="`echo $p | cut -d'=' -f2-`"	# Option value
+		value=${p#*=}	# Option value
 		value_lstripped=${value#\"}
 		value_rstripped=${value%\"}