Bitmap operations are much simpler and faster in case of small bitmaps, whicn fit into a single word. In linux/bitmap.h we have a machinery that allows compiler to replace actual function call with a few instructions if bitmaps passed into the function is small and its size is known at compile time. find_next_*_bit() lacks this functionality; despite users will benefit from it a lot. One important example is cpumask subsystem if NR_CPUS <= BITS_PER_LONG. In the very best case, the compiler may replace a find_*_bit() call for such a bitmap with a single ffs or ffz instruction. Yury Norov (6): arch: rearrahge headers inclusion order in asm/bitops for m68k and sh bitmap: move some macros from linux/bitmap.h to linux/bitops.h tools: sync bitops macro definitions with the kernel lib: inline _find_next_bit() wrappers lib: add fast path for find_next_*_bit() lib: add fast path for find_first_*_bit() and find_last_bit() arch/m68k/include/asm/bitops.h | 4 +- arch/sh/include/asm/bitops.h | 3 +- include/asm-generic/bitops/find.h | 123 +++++++++++++++++++++++++++--- include/asm-generic/bitops/le.h | 45 ++++++++++- include/linux/bitmap.h | 11 --- include/linux/bitops.h | 23 +++--- lib/find_bit.c | 68 ++--------------- tools/include/linux/bitmap.h | 11 --- tools/include/linux/bitops.h | 11 +++ 9 files changed, 188 insertions(+), 111 deletions(-) -- 2.25.1
