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| author | Yury Norov <yury.norov@gmail.com> | 2021-08-14 23:17:07 +0200 |
|---|---|---|
| committer | Yury Norov <yury.norov@gmail.com> | 2022-01-15 17:47:31 +0100 |
| commit | 7516be9931b8bc8bcaac8531f490b42ab11ded1e (patch) | |
| tree | 7437188f8ff4a29f05075c3932641aeec0b6d12f | |
| parent | include/linux: move for_each_bit() macros from bitops.h to find.h (diff) | |
| download | linux-7516be9931b8bc8bcaac8531f490b42ab11ded1e.tar.xz linux-7516be9931b8bc8bcaac8531f490b42ab11ded1e.zip | |
find: micro-optimize for_each_{set,clear}_bit()
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>
| -rw-r--r-- | include/linux/find.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/find.h b/include/linux/find.h index 4500e8ab93e2..ae9ed52b52b8 100644 --- a/include/linux/find.h +++ b/include/linux/find.h @@ -280,7 +280,7 @@ unsigned long find_next_bit_le(const void *addr, unsigned #endif #define for_each_set_bit(bit, addr, size) \ - for ((bit) = find_first_bit((addr), (size)); \ + for ((bit) = find_next_bit((addr), (size), 0); \ (bit) < (size); \ (bit) = find_next_bit((addr), (size), (bit) + 1)) @@ -291,7 +291,7 @@ unsigned long find_next_bit_le(const void *addr, unsigned (bit) = find_next_bit((addr), (size), (bit) + 1)) #define for_each_clear_bit(bit, addr, size) \ - for ((bit) = find_first_zero_bit((addr), (size)); \ + for ((bit) = find_next_zero_bit((addr), (size), 0); \ (bit) < (size); \ (bit) = find_next_zero_bit((addr), (size), (bit) + 1)) |