[PATCH] kbuild: reuse vmlinux.o in vmlinux_link

From: Sami Tolvanen
Date: Thu May 21 2020 - 16:27:25 EST


Instead of linking all compilation units again each time vmlinux_link is
called, reuse vmlinux.o from modpost_link.

With x86_64 allyesconfig, vmlinux_link is called three times and reusing
vmlinux.o reduces the build time ~38 seconds on my system (59% reduction
in the time spent in vmlinux_link).

Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
---
scripts/link-vmlinux.sh | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index d09ab4afbda4..c6cc4305950c 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -77,11 +77,8 @@ vmlinux_link()

if [ "${SRCARCH}" != "um" ]; then
objects="--whole-archive \
- ${KBUILD_VMLINUX_OBJS} \
+ vmlinux.o \
--no-whole-archive \
- --start-group \
- ${KBUILD_VMLINUX_LIBS} \
- --end-group \
${@}"

${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux} \

base-commit: b85051e755b0e9d6dd8f17ef1da083851b83287d
--
2.27.0.rc0.183.gde8f92d652-goog