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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>
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include/linux/find.h

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -280,7 +280,7 @@ unsigned long find_next_bit_le(const void *addr, unsigned
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#endif
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#define for_each_set_bit(bit, addr, size) \
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for ((bit) = find_first_bit((addr), (size)); \
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for ((bit) = find_next_bit((addr), (size), 0); \
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(bit) < (size); \
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(bit) = find_next_bit((addr), (size), (bit) + 1))
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@@ -291,7 +291,7 @@ unsigned long find_next_bit_le(const void *addr, unsigned
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(bit) = find_next_bit((addr), (size), (bit) + 1))
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#define for_each_clear_bit(bit, addr, size) \
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for ((bit) = find_first_zero_bit((addr), (size)); \
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for ((bit) = find_next_zero_bit((addr), (size), 0); \
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(bit) < (size); \
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(bit) = find_next_zero_bit((addr), (size), (bit) + 1))
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