kbuild: handle libs-y archives separately from built-in.o archives

[sagit-ice-cold/kernel_xiaomi_msm8998.git] / scripts / link-vmlinux.sh

diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index ba6c34e..0a08006 100755 (executable)
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -3,9 +3,12 @@
 # link vmlinux
 #
 # vmlinux is linked from the objects selected by $(KBUILD_VMLINUX_INIT) and
-# $(KBUILD_VMLINUX_MAIN). Most are built-in.o files from top-level directories
-# in the kernel tree, others are specified in arch/$(ARCH)/Makefile.
-# Ordering when linking is important, and $(KBUILD_VMLINUX_INIT) must be first.
+# $(KBUILD_VMLINUX_MAIN) and $(KBUILD_VMLINUX_LIBS). Most are built-in.o files
+# from top-level directories in the kernel tree, others are specified in
+# arch/$(ARCH)/Makefile. Ordering when linking is important, and
+# $(KBUILD_VMLINUX_INIT) must be first. $(KBUILD_VMLINUX_LIBS) are archives
+# which are linked conditionally (not within --whole-archive), and do not
+# require symbol indexes added.
 #
 # vmlinux
 #   ^
@@ -16,6 +19,9 @@
 #   +--< $(KBUILD_VMLINUX_MAIN)
 #   |    +--< drivers/built-in.o mm/built-in.o + more
 #   |
+#   +--< $(KBUILD_VMLINUX_LIBS)
+#   |    +--< lib/lib.a + more
+#   |
 #   +-< ${kallsymso} (see description in KALLSYMS section)
 #
 # vmlinux version (uname -v) cannot be updated during normal
@@ -37,12 +43,47 @@ info()
        fi
 }
 
+# Thin archive build here makes a final archive with symbol table and indexes
+# from vmlinux objects INIT and MAIN, which can be used as input to linker.
+# KBUILD_VMLINUX_LIBS archives should already have symbol table and indexes
+# added.
+#
+# Traditional incremental style of link does not require this step
+#
+# built-in.o output file
+#
+archive_builtin()
+{
+       if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then
+               info AR built-in.o
+               rm -f built-in.o;
+               ${AR} rcsTP${KBUILD_ARFLAGS} built-in.o                 \
+                                       ${KBUILD_VMLINUX_INIT}          \
+                                       ${KBUILD_VMLINUX_MAIN}
+       fi
+}
+
 # Link of vmlinux.o used for section mismatch analysis
 # ${1} output file
 modpost_link()
 {
-       ${LD} ${LDFLAGS} -r -o ${1} ${KBUILD_VMLINUX_INIT}                   \
-               --start-group ${KBUILD_VMLINUX_MAIN} --end-group
+       local objects
+
+       if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then
+               objects="--whole-archive                                \
+                       built-in.o                                      \
+                       --no-whole-archive                              \
+                       --start-group                                   \
+                       ${KBUILD_VMLINUX_LIBS}                          \
+                       --end-group"
+       else
+               objects="${KBUILD_VMLINUX_INIT}                         \
+                       --start-group                                   \
+                       ${KBUILD_VMLINUX_MAIN}                          \
+                       ${KBUILD_VMLINUX_LIBS}                          \
+                       --end-group"
+       fi
+       ${LD} ${LDFLAGS} -r -o ${1} ${objects}
 }
 
 # Link of vmlinux
@@ -51,18 +92,50 @@ modpost_link()
 vmlinux_link()
 {
        local lds="${objtree}/${KBUILD_LDS}"
+       local objects
 
        if [ "${SRCARCH}" != "um" ]; then
-               ${LD} ${LDFLAGS} ${LDFLAGS_vmlinux} -o ${2}                  \
-                       -T ${lds} ${KBUILD_VMLINUX_INIT}                     \
-                       --start-group ${KBUILD_VMLINUX_MAIN} --end-group ${1}
+               if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then
+                       objects="--whole-archive                        \
+                               built-in.o                              \
+                               --no-whole-archive                      \
+                               --start-group                           \
+                               ${KBUILD_VMLINUX_LIBS}                  \
+                               --end-group                             \
+                               ${1}"
+               else
+                       objects="${KBUILD_VMLINUX_INIT}                 \
+                               --start-group                           \
+                               ${KBUILD_VMLINUX_MAIN}                  \
+                               ${KBUILD_VMLINUX_LIBS}                  \
+                               --end-group                             \
+                               ${1}"
+               fi
+
+               ${LD} ${LDFLAGS} ${LDFLAGS_vmlinux} -o ${2}             \
+                       -T ${lds} ${objects}
        else
-               ${CC} ${CFLAGS_vmlinux} -o ${2}                              \
-                       -Wl,-T,${lds} ${KBUILD_VMLINUX_INIT}                 \
-                       -Wl,--start-group                                    \
-                                ${KBUILD_VMLINUX_MAIN}                      \
-                       -Wl,--end-group                                      \
-                       -lutil -lrt -lpthread ${1}
+               if [ -n "${CONFIG_THIN_ARCHIVES}" ]; then
+                       objects="-Wl,--whole-archive                    \
+                               built-in.o                              \
+                               -Wl,--no-whole-archive                  \
+                               -Wl,--start-group                       \
+                               ${KBUILD_VMLINUX_LIBS}                  \
+                               -Wl,--end-group                         \
+                               ${1}"
+               else
+                       objects="${KBUILD_VMLINUX_INIT}                 \
+                               -Wl,--start-group                       \
+                               ${KBUILD_VMLINUX_MAIN}                  \
+                               ${KBUILD_VMLINUX_LIBS}                  \
+                               -Wl,--end-group                         \
+                               ${1}"
+               fi
+
+               ${CC} ${CFLAGS_vmlinux} -o ${2}                         \
+                       -Wl,-T,${lds}                                   \
+                       ${objects}                                      \
+                       -lutil -lrt -lpthread
                rm -f linux
        fi
 }
@@ -118,6 +191,7 @@ cleanup()
        rm -f .tmp_kallsyms*
        rm -f .tmp_version
        rm -f .tmp_vmlinux*
+       rm -f built-in.o
        rm -f System.map
        rm -f vmlinux
        rm -f vmlinux.o
@@ -161,13 +235,6 @@ case "${KCONFIG_CONFIG}" in
        . "./${KCONFIG_CONFIG}"
 esac
 
-#link vmlinux.o
-info LD vmlinux.o
-modpost_link vmlinux.o
-
-# modpost vmlinux.o to check for section mismatches
-${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o
-
 # Update version
 info GEN .version
 if [ ! -r .version ]; then
@@ -181,6 +248,15 @@ fi;
 # final build of init/
 ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init
 
+archive_builtin
+
+#link vmlinux.o
+info LD vmlinux.o
+modpost_link vmlinux.o
+
+# modpost vmlinux.o to check for section mismatches
+${MAKE} -f "${srctree}/scripts/Makefile.modpost" vmlinux.o
+
 kallsymso=""
 kallsyms_vmlinux=""
 if [ -n "${CONFIG_KALLSYMS}" ]; then