kernel-ark/arch/ppc64/kernel/vdso64/Makefile
Benjamin Herrenschmidt 1b29f9d13e [PATCH] ppc64: add PT_NOTE section to vDSO
This patch from Roland adds a PT_NOTE section to both 32 and 64 bits vDSOs
to expose the kernel version to glibc, thus avoiding a uname syscall on
every launch.  This is equivalent to the patches Roland posted already for
x86 and x86-64.

Note: the 64 bits .note is actually using the 32 bits format.  This is
normal.  The ELF spec specifies a different format for 64 bits .note, but
for some reason, this was never properly implemented, the core dumps for
example are all using 32 bits format .note, and binutils cannot even read a
64 bits format .note.  Talking to our toolchain folks, they think we'd
rather stick to 32 bits format .note everywhere and get the spec fixed some
day ...

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:43 -07:00

36 lines
955 B
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
# Build rules
targets := $(obj-vdso64) vdso64.so
obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
EXTRA_CFLAGS := -shared -s -fno-common -fno-builtin
EXTRA_CFLAGS += -nostdlib -Wl,-soname=linux-vdso64.so.1
EXTRA_AFLAGS := -D__VDSO64__ -s
obj-y += vdso64_wrapper.o
extra-y += vdso64.lds
CPPFLAGS_vdso64.lds += -P -C -U$(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: $(src)/vdso64.lds $(obj-vdso64)
$(call if_changed,vdso64ld)
# 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 $@ $<