From 746479cdcbb131a0645e8cb4a35d6b26126e3e4c Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 18 Sep 2013 11:45:36 +0200 Subject: s390/bitops: use generic find bit functions / reimplement _left variant Just like all other architectures we should use out-of-line find bit operations, since the inline variant bloat the size of the kernel image. And also like all other architecures we should only supply optimized variants of the __ffs, ffs, etc. primitives. Therefore this patch removes the inlined s390 find bit functions and uses the generic out-of-line variants instead. The optimization of the primitives follows with the next patch. With this patch also the functions find_first_bit_left() and find_next_bit_left() have been reimplemented, since logically, they are nothing else but a find_first_bit()/find_next_bit() implementation that use an inverted __fls() instead of __ffs(). Also the restriction that these functions only work on machines which support the "flogr" instruction is gone now. This reduces the size of the kernel image (defconfig, -march=z9-109) by 144,482 bytes. Alone the size of the function build_sched_domains() gets reduced from 7 KB to 3,5 KB. We also git rid of unused functions like find_first_bit_le()... Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/Kconfig | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/s390/Kconfig') diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 7143793859fa..a02177fb5ec1 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -99,6 +99,7 @@ config S390 select CLONE_BACKWARDS2 select GENERIC_CLOCKEVENTS select GENERIC_CPU_DEVICES if !SMP + select GENERIC_FIND_FIRST_BIT select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL_OLD select HAVE_ALIGNED_STRUCT_PAGE if SLUB -- cgit v1.2.3-55-g7522