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
9 # files to link into kernel
10 obj-y := vma.o vdso.o vdso-syms.o
12 vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
14 $(obj)/vdso.o: $(obj)/vdso.so
16 targets += vdso.so vdso.lds $(vobjs-y) vdso-syms.o
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 $@
23 export CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
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)
30 $(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so
32 $(obj)/vdso.so: $(src)/vdso.lds $(vobjs) FORCE
33 $(call if_changed,syscall)
35 CF := $(PROFILING) -mcmodel=small -fPIC -g0 -O2 -fasynchronous-unwind-tables -m64
37 $(obj)/vclock_gettime.o: CFLAGS = $(CF)
38 $(obj)/vgetcpu.o: CFLAGS = $(CF)
40 # We also create a special relocatable object that should mirror the symbol
41 # table and layout of the linked DSO. With ld -R we can then refer to
42 # these symbols in the kernel code rather than hand-coded addresses.
43 extra-y += vdso-syms.o
44 $(obj)/built-in.o: $(obj)/vdso-syms.o
45 $(obj)/built-in.o: ld_flags += -R $(obj)/vdso-syms.o
47 SYSCFLAGS_vdso-syms.o = -r -d
48 $(obj)/vdso-syms.o: $(src)/vdso.lds $(vobjs) FORCE
49 $(call if_changed,syscall)