linux

modpost: Optimize symbol search from linear to binary search [ Upstream commit 4074532758c5c367d3fcb8d124150824a254659d ] Modify modpost to use binary search for converting addresses back into symbol references. Previously it used linear search. This change saves a few seconds of wall time for defconfig builds, but can save several minutes on allyesconfigs. Before: $ make LLVM=1 -j128 allyesconfig vmlinux -s KCFLAGS="-Wno-error" $ time scripts/mod/modpost -M -m -a -N -o vmlinux.symvers vmlinux.o 198.38user 1.27system 3:19.71elapsed After: $ make LLVM=1 -j128 allyesconfig vmlinux -s KCFLAGS="-Wno-error" $ time scripts/mod/modpost -M -m -a -N -o vmlinux.symvers vmlinux.o 11.91user 0.85system 0:12.78elapsed Signed-off-by: Jack Brennen <jbrennen@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Stable-dep-of: 1102f9f85bf6 ("modpost: do not make find_tosym() return NULL") Signed-off-by: Sasha Levin <sashal@kernel.org> 2023-09-26 08:40:44 -04:00