arch/x86/vdso/Makefile

   1 #
   2 # x86-64 vDSO.
   3 #
   4
   5 # files to link into the vdso
   6 # vdso-start.o has to be first
   7 vobjs-y := vdso-start.o vdso-note.o vclock_gettime.o vgetcpu.o vvar.o
   8
   9 # files to link into kernel
  10 obj-y := vma.o vdso.o vdso-syms.o
  11
  12 vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
  13
  14 $(obj)/vdso.o: $(obj)/vdso.so
  15
  16 targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y) vdso-syms.o
  17
  18 # The DSO images are built using a special linker script.
  19 quiet_cmd_syscall = SYSCALL $@
  20       cmd_syscall = $(CC) -m elf_x86_64 -nostdlib $(SYSCFLAGS_$(@F)) \
  21                           -Wl,-T,$(filter-out FORCE,$^) -o $@
  22
  23 export CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
  24
  25 vdso-flags = -fPIC -shared -Wl,-soname=linux-vdso.so.1 \
  26                  $(call ld-option, -Wl$(comma)--hash-style=sysv) \
  27                 -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
  28 SYSCFLAGS_vdso.so = $(vdso-flags)
  29 SYSCFLAGS_vdso.so.dbg = $(vdso-flags)
  30
  31 $(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so
  32
  33 $(obj)/vdso.so: $(src)/vdso.lds $(vobjs) FORCE
  34
  35 $(obj)/vdso.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
  36         $(call if_changed,syscall)
  37
  38 $(obj)/%.so: OBJCOPYFLAGS := -S
  39 $(obj)/%.so: $(obj)/%.so.dbg FORCE
  40         $(call if_changed,objcopy)
  41
  42 CFL := $(PROFILING) -mcmodel=small -fPIC -g0 -O2 -fasynchronous-unwind-tables -m64
  43
  44 $(obj)/vclock_gettime.o: KBUILD_CFLAGS = $(CFL)
  45 $(obj)/vgetcpu.o: KBUILD_CFLAGS = $(CFL)
  46
  47 # We also create a special relocatable object that should mirror the symbol
  48 # table and layout of the linked DSO.  With ld -R we can then refer to
  49 # these symbols in the kernel code rather than hand-coded addresses.
  50 extra-y += vdso-syms.o
  51 $(obj)/built-in.o: $(obj)/vdso-syms.o
  52 $(obj)/built-in.o: ld_flags += -R $(obj)/vdso-syms.o
  53
  54 SYSCFLAGS_vdso-syms.o = -r -d
  55 $(obj)/vdso-syms.o: $(src)/vdso.lds $(vobjs) FORCE
  56         $(call if_changed,syscall)
  57
  58 quiet_cmd_vdso_install = INSTALL $@
  59       cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
  60 vdso.so:
  61         @mkdir -p $(MODLIB)/vdso
  62         $(call cmd,vdso_install)
  63
  64 vdso_install: vdso.so