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Subject[PATCH v4 00/13] lib/find_bit: fast path for small bitmaps
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Bitmap operations are much simpler and faster in case of small bitmaps
which fit into a single word. In linux/bitmap.c we have a machinery that
allows compiler to replace actual function call with a few instructions
if bitmaps passed into the function are small and their size is known at
compile time.

find_*_bit() API lacks this functionality; but users will benefit from it
a lot. One important example is cpumask subsystem when
NR_CPUS <= BITS_PER_LONG.

v1: https://www.spinics.net/lists/kernel/msg3804727.html
v2: https://www.spinics.net/lists/linux-m68k/msg16945.html
v3: https://www.spinics.net/lists/kernel/msg3837020.html
v4: - move le.h header together with find.h for m68 and sh;
- preserve small_const_nbits() macro;
- drop FAST_PATH config option as this series doesn't increase .text,
instead, it compacts it;
- add Andy and Rasmus as reviewers of BITMAP API.

Yury Norov (13):
tools: disable -Wno-type-limits
tools: bitmap: sync function declarations with the kernel
arch: rearrange headers inclusion order in asm/bitops for m68k and sh
lib: introduce BITS_{FIRST,LAST} macro
tools: sync BITS_MASK macros with the kernel
lib: extend the scope of small_const_nbits() macro
tools: sync small_const_nbits() macro with the kernel
lib: inline _find_next_bit() wrappers
tools: sync find_next_bit implementation
lib: add fast path for find_next_*_bit()
lib: add fast path for find_first_*_bit() and find_last_bit()
tools: sync lib/find_bit implementation
MAINTAINERS: Add entry for the bitmap API

MAINTAINERS | 16 ++++
arch/m68k/include/asm/bitops.h | 6 +-
arch/sh/include/asm/bitops.h | 5 +-
include/asm-generic/bitops/find.h | 108 +++++++++++++++++++++---
include/asm-generic/bitops/le.h | 38 ++++++++-
include/asm-generic/bitsperlong.h | 9 ++
include/linux/bitmap.h | 30 +++----
include/linux/bitops.h | 12 ---
include/linux/bits.h | 6 ++
include/linux/cpumask.h | 8 +-
include/linux/netdev_features.h | 2 +-
include/linux/nodemask.h | 2 +-
lib/bitmap.c | 26 +++---
lib/find_bit.c | 72 +++-------------
lib/genalloc.c | 8 +-
tools/include/asm-generic/bitops/find.h | 85 +++++++++++++++++--
tools/include/asm-generic/bitsperlong.h | 3 +
tools/include/linux/bitmap.h | 31 +++----
tools/include/linux/bits.h | 6 ++
tools/lib/bitmap.c | 10 +--
tools/lib/find_bit.c | 56 +++++-------
tools/scripts/Makefile.include | 1 +
tools/testing/radix-tree/bitmap.c | 4 +-
23 files changed, 340 insertions(+), 204 deletions(-)

--
2.25.1

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