From: Andreas Gruenbacher Date: Mon, 27 Jan 2025 16:52:39 +0000 (+0100) Subject: bcachefs: implement eytzinger0_find_ge directly X-Git-Tag: v6.15-rc1~146^2~114 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=11223d0e7b091b11e0e533850c1007e8fc797c68;p=thirdparty%2Fkernel%2Flinux.git bcachefs: implement eytzinger0_find_ge directly Implement eytzinger0_find_ge() directly instead of implementing it in terms of eytzinger0_find_le() and adjusting the result. This turns eytzinger0_find_ge() into a minimum search, so when there are duplicate elements, the result of eytzinger0_find_ge() will now always point at the first matching element. Signed-off-by: Andreas Gruenbacher Signed-off-by: Kent Overstreet --- diff --git a/fs/bcachefs/eytzinger.h b/fs/bcachefs/eytzinger.h index 568a04b16d093..e3713b7b4c276 100644 --- a/fs/bcachefs/eytzinger.h +++ b/fs/bcachefs/eytzinger.h @@ -275,15 +275,17 @@ static inline int eytzinger0_find_gt(void *base, size_t nr, size_t size, return n - 1; } +/* return smallest node >= @search, or -1 if not found */ static inline int eytzinger0_find_ge(void *base, size_t nr, size_t size, cmp_func_t cmp, const void *search) { - ssize_t idx = eytzinger0_find_le(base, nr, size, cmp, search); - - if (idx < nr && !cmp(base + idx * size, search)) - return idx; + void *base1 = base - size; + unsigned n = 1; - return eytzinger0_next(idx, nr); + while (n <= nr) + n = eytzinger1_child(n, cmp(base1 + n * size, search) < 0); + n >>= __ffs(n + 1) + 1; + return n - 1; } #define eytzinger0_find(base, nr, size, _cmp, search) \