[POWERPC] cell: Unify spufs syscall path

At present, a built-in spufs will not use the spufs_calls callbacks, but
directly call sys_spu_create.  This saves us an indirect branch, but
means we have duplicated functions - one for CONFIG_SPU_FS=y and one for
=m.

This change unifies the spufs syscall path, and provides access to the
spufs_calls structure through a get/put pair.  At present, the only user
of the spufs_calls structure is spu_syscalls.c, but this will facilitate
adding the coredump calls later.

Everyone likes numbers, right?  Here's a before/after comparison with
CONFIG_SPU_FS=y, doing spu_create(); close(); 64k times.

Before:
	[jk@cell ~]$ time ./spu_create
	performing 65536 spu_create calls

	real    0m24.075s
	user    0m0.146s
	sys     0m23.925s

After:
	[jk@cell ~]$ time ./spu_create
	performing 65536 spu_create calls

	real    0m24.777s
	user    0m0.141s
	sys     0m24.631s

So, we're adding around 11us per syscall, at the benefit of having
only one syscall path.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 1 insertions, 3 deletions

diff --git a/arch/powerpc/platforms/cell/Makefile b/arch/powerpc/platforms/cell/Makefile
index f88a7c76f296..40f78e908953 100644
--- a/arch/powerpc/platforms/cell/Makefile
+++ b/arch/powerpc/platforms/cell/Makefile
@@ -13,15 +13,13 @@ obj-$(CONFIG_PPC_CELL_NATIVE)		+= smp.o
 endif
 
 # needed only when building loadable spufs.ko
-spufs-modular-$(CONFIG_SPU_FS)		+= spu_syscalls.o
 spu-priv1-$(CONFIG_PPC_CELL_NATIVE)	+= spu_priv1_mmio.o
 
 spu-manage-$(CONFIG_PPC_CELLEB)		+= spu_manage.o
 spu-manage-$(CONFIG_PPC_CELL_NATIVE)	+= spu_manage.o
 
 obj-$(CONFIG_SPU_BASE)			+= spu_callbacks.o spu_base.o \
-					   spu_coredump.o \
-					   $(spufs-modular-m) \
+					   spu_coredump.o spu_syscalls.o \
 					   $(spu-priv1-y) \
 					   $(spu-manage-y) \
 					   spufs/