From: Yury Norov Date: Tue, 10 Mar 2026 20:53:02 +0000 (-0400) Subject: lib: crypto: fix comments for count_leading_zeros() X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=18c48899653fa7a04120537c228031b5c7e4e9d6;p=thirdparty%2Fkernel%2Flinux.git lib: crypto: fix comments for count_leading_zeros() count_leading_zeros() is based on fls(), which is defined for x == 0, contrary to __ffs() family. The comment in crypto/mpi erroneously states that the function may return undef in such case. Fix the comment together with the outdated function signature, and now that COUNT_LEADING_ZEROS_0 is not referenced in the codebase, get rid of it too. Reviewed-by: Andy Shevchenko Acked-by: Eric Biggers Signed-off-by: Yury Norov --- diff --git a/include/linux/count_zeros.h b/include/linux/count_zeros.h index 5b8ff5ac660da..4e5680327ece8 100644 --- a/include/linux/count_zeros.h +++ b/include/linux/count_zeros.h @@ -18,7 +18,7 @@ * * If the MSB of @x is set, the result is 0. * If only the LSB of @x is set, then the result is BITS_PER_LONG-1. - * If @x is 0 then the result is COUNT_LEADING_ZEROS_0. + * If @x is 0 then the result is BITS_PER_LONG. */ static inline int count_leading_zeros(unsigned long x) { @@ -28,8 +28,6 @@ static inline int count_leading_zeros(unsigned long x) return BITS_PER_LONG - fls64(x); } -#define COUNT_LEADING_ZEROS_0 BITS_PER_LONG - /** * count_trailing_zeros - Count the number of zeros from the LSB forwards * @x: The value diff --git a/lib/crypto/mpi/longlong.h b/lib/crypto/mpi/longlong.h index b6fa1d08fb55b..6d31c3a729f12 100644 --- a/lib/crypto/mpi/longlong.h +++ b/lib/crypto/mpi/longlong.h @@ -66,12 +66,12 @@ * denominator). Like udiv_qrnnd but the numbers are signed. The quotient * is rounded towards 0. * - * 5) count_leading_zeros(count, x) counts the number of zero-bits from the + * 5) count_leading_zeros(x) counts the number of zero-bits from the * msb to the first non-zero bit in the UWtype X. This is the number of - * steps X needs to be shifted left to set the msb. Undefined for X == 0, - * unless the symbol COUNT_LEADING_ZEROS_0 is defined to some value. + * steps X needs to be shifted left to set the msb. + * count_leading_zeros(0) == BITS_PER_LONG * - * 6) count_trailing_zeros(count, x) like count_leading_zeros, but counts + * 6) count_trailing_zeros() like count_leading_zeros(), but counts * from the least significant end. * * 7) add_ssaaaa(high_sum, low_sum, high_addend_1, low_addend_1,