arch/x86/um/vdso/Makefile

   1 #
   2 # Building vDSO images for x86.
   3 #
   4
   5 VDSO64-y                := y
   6
   7 vdso-install-$(VDSO64-y)        += vdso.so
   8
   9
  10 # files to link into the vdso
  11 vobjs-y := vdso-note.o um_vdso.o
  12
  13 # files to link into kernel
  14 obj-$(VDSO64-y)                 += vdso.o vma.o
  15
  16 vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
  17
  18 $(obj)/vdso.o: $(obj)/vdso.so
  19
  20 targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y)
  21
  22 export CPPFLAGS_vdso.lds += -P -C
  23
  24 VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
  25        -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
  26
  27 $(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so
  28
  29 $(obj)/vdso.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
  30         $(call if_changed,vdso)
  31
  32 $(obj)/%.so: OBJCOPYFLAGS := -S
  33 $(obj)/%.so: $(obj)/%.so.dbg FORCE
  34         $(call if_changed,objcopy)
  35
  36 #
  37 # Don't omit frame pointers for ease of userspace debugging, but do
  38 # optimize sibling calls.
  39 #
  40 CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
  41        $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \
  42        -fno-omit-frame-pointer -foptimize-sibling-calls
  43
  44 $(vobjs): KBUILD_CFLAGS += $(CFL)
  45
  46 #
  47 # vDSO code runs in userspace and -pg doesn't help with profiling anyway.
  48 #
  49 CFLAGS_REMOVE_vdso-note.o = -pg
  50 CFLAGS_REMOVE_um_vdso.o = -pg
  51
  52 targets += vdso-syms.lds
  53 obj-$(VDSO64-y)                 += vdso-syms.lds
  54
  55 #
  56 # Match symbols in the DSO that look like VDSO*; produce a file of constants.
  57 #
  58 sed-vdsosym := -e 's/^00*/0/' \
  59         -e 's/^\([0-9a-fA-F]*\) . \(VDSO[a-zA-Z0-9_]*\)$$/\2 = 0x\1;/p'
  60 quiet_cmd_vdsosym = VDSOSYM $@
  61 define cmd_vdsosym
  62         $(NM) $< | LC_ALL=C sed -n $(sed-vdsosym) | LC_ALL=C sort > $@
  63 endef
  64
  65 $(obj)/%-syms.lds: $(obj)/%.so.dbg FORCE
  66         $(call if_changed,vdsosym)
  67
  68 #
  69 # The DSO images are built using a special linker script.
  70 #
  71 quiet_cmd_vdso = VDSO    $@
  72       cmd_vdso = $(CC) -nostdlib -o $@ \
  73                        $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
  74                        -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \
  75                  sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
  76
  77 VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
  78 GCOV_PROFILE := n
  79
  80 #
  81 # Install the unstripped copy of vdso*.so listed in $(vdso-install-y).
  82 #
  83 quiet_cmd_vdso_install = INSTALL $@
  84       cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
  85 $(vdso-install-y): %.so: $(obj)/%.so.dbg FORCE
  86         @mkdir -p $(MODLIB)/vdso
  87         $(call cmd,vdso_install)
  88
  89 PHONY += vdso_install $(vdso-install-y)
  90 vdso_install: $(vdso-install-y)