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2022-06-03include/linux/find: Fix documentationAnna-Maria Behnsen1-3/+3
The order of the arguments in function documentation doesn't fit the implementation. Change the documentation so that it corresponds to the code. This prevent people to get confused when reading the documentation. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-01-15bitmap: unify find_bit operationsYury Norov1-0/+56
bitmap_for_each_{set,clear}_region() are similar to for_each_bit() macros in include/linux/find.h, but interface and implementation of them are different. This patch adds for_each_bitrange() macros and drops unused bitmap_*_region() API in sake of unification. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Dennis Zhou <dennis@kernel.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
2022-01-15find: micro-optimize for_each_{set,clear}_bit()Yury Norov1-2/+2
The macros iterate thru all set/clear bits in a bitmap. They search a first bit using find_first_bit(), and the rest bits using find_next_bit(). Since find_next_bit() is called shortly after find_first_bit(), we can save few lines of I-cache by not using find_first_bit(). Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2022-01-15include/linux: move for_each_bit() macros from bitops.h to find.hYury Norov1-0/+34
for_each_bit() macros depend on find_bit() machinery, and so the proper place for them is the find.h header. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2022-01-15lib: add find_first_and_bit()Yury Norov1-0/+27
Currently find_first_and_bit() is an alias to find_next_and_bit(). However, it is widely used in cpumask, so it worth to optimize it. This patch adds its own implementation for find_first_and_bit(). On x86_64 find_bit_benchmark says: Before (#define find_first_and_bit(...) find_next_and_bit(..., 0): Start testing find_bit() with random-filled bitmap [ 140.291468] find_first_and_bit: 46890919 ns, 32671 iterations Start testing find_bit() with sparse bitmap [ 140.295028] find_first_and_bit: 7103 ns, 1 iterations After: Start testing find_bit() with random-filled bitmap [ 162.574907] find_first_and_bit: 25045813 ns, 32846 iterations Start testing find_bit() with sparse bitmap [ 162.578458] find_first_and_bit: 4900 ns, 1 iterations (Thanks to Alexey Klimov for thorough testing.) Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Alexey Klimov <aklimov@redhat.com>
2022-01-15arch: remove GENERIC_FIND_FIRST_BIT entirelyYury Norov1-13/+0
In 5.12 cycle we enabled GENERIC_FIND_FIRST_BIT config option for ARM64 and MIPS. It increased performance and shrunk .text size; and so far I didn't receive any negative feedback on the change. https://lore.kernel.org/linux-arch/20210225135700.1381396-1-yury.norov@gmail.com/ Now I think it's a good time to switch all architectures to use find_{first,last}_bit() unconditionally, and so remove corresponding config option. The patch does't introduce functioal changes for arc, arm, arm64, mips, m68k, s390 and x86, for other architectures I expect improvement both in performance and .text size. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Alexander Lobakin <alobakin@pm.me> (mips) Reviewed-by: Alexander Lobakin <alobakin@pm.me> (mips) Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Will Deacon <will@kernel.org> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2022-01-15include: move find.h from asm_generic to linuxYury Norov1-0/+268
find_bit API and bitmap API are closely related, but inclusion paths are different - include/asm-generic and include/linux, correspondingly. In the past it made a lot of troubles due to circular dependencies and/or undefined symbols. Fix this by moving find.h under include/linux. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>