linux_dsm_epyc7002/arch/powerpc/kernel/vdso64/Makefile
Michael Ellerman 787b393c9f powerpc/vdso: Emit GNU & SysV hashes
Andy Lutomirski says:

  Some dynamic loaders may be slightly faster if a GNU hash is
  available.

  This is unlikely to have any measurable effect on the time it takes
  to resolve vdso symbols (since there are so few of them).  In some
  contexts, it can be a win for a different reason: if every DSO has a
  GNU hash section, then libc can avoid calculating SysV hashes at
  all. Both musl and glibc appear to have this optimization.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-01 16:52:00 +10:00

52 lines
1.4 KiB
Makefile

# List of files in the vdso, has to be asm only for now
obj-vdso64 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o getcpu.o
# Build rules
targets := $(obj-vdso64) vdso64.so vdso64.so.dbg
obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
GCOV_PROFILE := n
ccflags-y := -shared -fno-common -fno-builtin
ccflags-y += -nostdlib -Wl,-soname=linux-vdso64.so.1 \
$(call cc-ldoption, -Wl$(comma)--hash-style=both)
asflags-y := -D__VDSO64__ -s
obj-y += vdso64_wrapper.o
extra-y += vdso64.lds
CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
# Force dependency (incbin is bad)
$(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
# link rule for the .so file, .lds has to be first
$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64)
$(call if_changed,vdso64ld)
# strip rule for the .so file
$(obj)/%.so: OBJCOPYFLAGS := -S
$(obj)/%.so: $(obj)/%.so.dbg FORCE
$(call if_changed,objcopy)
# assembly rules for the .S files
$(obj-vdso64): %.o: %.S
$(call if_changed_dep,vdso64as)
# actual build commands
quiet_cmd_vdso64ld = VDSO64L $@
cmd_vdso64ld = $(CC) $(c_flags) -Wl,-T $^ -o $@
quiet_cmd_vdso64as = VDSO64A $@
cmd_vdso64as = $(CC) $(a_flags) -c -o $@ $<
# install commands for the unstripped file
quiet_cmd_vdso_install = INSTALL $@
cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
vdso64.so: $(obj)/vdso64.so.dbg
@mkdir -p $(MODLIB)/vdso
$(call cmd,vdso_install)
vdso_install: vdso64.so