Date: Thu, 6 Jul 2023 18:37:42 GMT From: Doug Moore <dougm@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: d4e236c70b0d - main - inline_ffs: remove backup binary implementation Message-ID: <202307061837.366Ibg5V097884@gitrepo.freebsd.org>
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The branch main has been updated by dougm: URL: https://cgit.FreeBSD.org/src/commit/?id=d4e236c70b0db52cd7232a11ad0a2ed895e65f70 commit d4e236c70b0db52cd7232a11ad0a2ed895e65f70 Author: Doug Moore <dougm@FreeBSD.org> AuthorDate: 2023-07-06 18:36:12 +0000 Commit: Doug Moore <dougm@FreeBSD.org> CommitDate: 2023-07-06 18:36:12 +0000 inline_ffs: remove backup binary implementation There is no longer be any point to maintaining a binary search routine for ffs; inlines will always do it as well or better. Reviewed by: mhorne Differential Revision: https://reviews.freebsd.org/D40703 --- sys/kern/subr_blist.c | 35 +++-------------------------------- 1 file changed, 3 insertions(+), 32 deletions(-) diff --git a/sys/kern/subr_blist.c b/sys/kern/subr_blist.c index ba13fb4efd80..aa0ba6a88610 100644 --- a/sys/kern/subr_blist.c +++ b/sys/kern/subr_blist.c @@ -184,42 +184,13 @@ bitrange(int n, int count) ((u_daddr_t)-1 >> (BLIST_RADIX - (n + count)))); } -/* - * Find the first bit set in a u_daddr_t. - */ -static inline int -generic_bitpos(u_daddr_t mask) -{ - int hi, lo, mid; - - lo = 0; - hi = BLIST_RADIX; - while (lo + 1 < hi) { - mid = (lo + hi) >> 1; - if (mask & bitrange(0, mid)) - hi = mid; - else - lo = mid; - } - return (lo); -} - static inline int bitpos(u_daddr_t mask) { - switch (sizeof(mask)) { -#ifdef HAVE_INLINE_FFSLL - case sizeof(long long): - return (ffsll(mask) - 1); -#endif -#ifdef HAVE_INLINE_FFS - case sizeof(int): - return (ffs(mask) - 1); -#endif - default: - return (generic_bitpos(mask)); - } + _Static_assert(sizeof(long long) >= sizeof(mask), + "mask too big for ffsll()"); + return (ffsll(mask) - 1); } /*
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