kbuild: remove unnecessary in-subshell execution

The commands surrounded by ( ) are executed in a subshell, but in
most cases, we do not need to spawn an extra subshell.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 9800178fdcd2b20b44759987bb7a45a24132621f..f8e2794107edefa9034c867c6d00f6d69ae31edc 100644 (file)
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -312,11 +312,11 @@ $(real-obj-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 #
 # These mirror gensymtypes_c and co above, keep them in synch.
 cmd_gensymtypes_S =                                                         \
-    (echo "\#include <linux/kernel.h>" ;                                    \
+   { echo "\#include <linux/kernel.h>" ;                                    \
      echo "\#include <asm/asm-prototypes.h>" ;                              \
     $(CPP) $(a_flags) $< |                                                  \
      grep "\<___EXPORT_SYMBOL\>" |                                          \
-     sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
+     sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ; } | \
     $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
     $(GENKSYMS) $(if $(1), -T $(2))                                         \
      $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index c6fc295e0c484a1407da0a2ff2f9f75dfd3a4f3a..c0abd9a779c3b1e2b117508f4b6bb2c25fc4047a 100644 (file)
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -271,7 +271,7 @@ DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
 # Generate an assembly file to wrap the output of the device tree compiler
 quiet_cmd_dt_S_dtb= DTB     $@
 cmd_dt_S_dtb=                                          \
-(                                                      \
+{                                                      \
        echo '\#include <asm-generic/vmlinux.lds.h>';   \
        echo '.section .dtb.init.rodata,"a"';           \
        echo '.balign STRUCT_ALIGNMENT';                \
@@ -281,7 +281,7 @@ cmd_dt_S_dtb=                                               \
        echo '__dtb_$(subst -,_,$(*F))_end:';           \
        echo '.global __dtb_$(subst -,_,$(*F))_end';    \
        echo '.balign STRUCT_ALIGNMENT';                \
-) > $@
+} > $@
 
 $(obj)/%.dtb.S: $(obj)/%.dtb FORCE
        $(call if_changed,dt_S_dtb)
@@ -335,20 +335,20 @@ printf "%08x\n" $$dec_size |                                              \
 )
 
 quiet_cmd_bzip2 = BZIP2   $@
-      cmd_bzip2 = (cat $(real-prereqs) | bzip2 -9 && $(size_append)) > $@
+      cmd_bzip2 = { cat $(real-prereqs) | bzip2 -9 && $(size_append); } > $@
 
 # Lzma
 # ---------------------------------------------------------------------------
 
 quiet_cmd_lzma = LZMA    $@
-      cmd_lzma = (cat $(real-prereqs) | lzma -9 && $(size_append)) > $@
+      cmd_lzma = { cat $(real-prereqs) | lzma -9 && $(size_append); } > $@
 
 quiet_cmd_lzo = LZO     $@
-      cmd_lzo = (cat $(real-prereqs) | lzop -9 && $(size_append)) > $@
+      cmd_lzo = { cat $(real-prereqs) | lzop -9 && $(size_append); } > $@
 
 quiet_cmd_lz4 = LZ4     $@
-      cmd_lz4 = (cat $(real-prereqs) | lz4c -l -c1 stdin stdout && \
-                  $(size_append)) > $@
+      cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout && \
+                  $(size_append); } > $@
 
 # U-Boot mkimage
 # ---------------------------------------------------------------------------
@@ -390,12 +390,11 @@ quiet_cmd_uimage = UIMAGE  $@
 # big dictionary would increase the memory usage too much in the multi-call
 # decompression mode. A BCJ filter isn't used either.
 quiet_cmd_xzkern = XZKERN  $@
-      cmd_xzkern = (cat $(real-prereqs) | \
-       sh $(srctree)/scripts/xz_wrap.sh && $(size_append)) > $@
+      cmd_xzkern = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh && \
+                     $(size_append); } > $@
 
 quiet_cmd_xzmisc = XZMISC  $@
-      cmd_xzmisc = (cat $(real-prereqs) | \
-       xz --check=crc32 --lzma2=dict=1MiB) > $@
+      cmd_xzmisc = cat $(real-prereqs) | xz --check=crc32 --lzma2=dict=1MiB > $@
 
 # ASM offsets
 # ---------------------------------------------------------------------------

diff --git a/scripts/mkcompile_h b/scripts/mkcompile_h
index 87f1fc9801d7330e86bfd39f9077c899ba8589cc..2339f86126cb8f0747086a8e9a155dbf87b6521a 100755 (executable)
--- a/scripts/mkcompile_h
+++ b/scripts/mkcompile_h
@@ -62,7 +62,7 @@ UTS_TRUNCATE="cut -b -$UTS_LEN"
 
 # Generate a temporary compile.h
 
-( echo /\* This file is auto generated, version $VERSION \*/
+{ echo /\* This file is auto generated, version $VERSION \*/
   if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi
 
   echo \#define UTS_MACHINE \"$ARCH\"
@@ -73,7 +73,7 @@ UTS_TRUNCATE="cut -b -$UTS_LEN"
   echo \#define LINUX_COMPILE_HOST \"`echo $LINUX_COMPILE_HOST | $UTS_TRUNCATE`\"
 
   echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | grep ' version ' | sed 's/[[:space:]]*$//'`\"
-) > .tmpcompile
+} > .tmpcompile
 
 # Only replace the real compile.h if the new one is different,
 # in order to preserve the timestamp and avoid unnecessary