diff options
author | Kent Overstreet <kent.overstreet@linux.dev> | 2023-11-30 02:20:42 -0500 |
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committer | Kent Overstreet <kent.overstreet@linux.dev> | 2023-11-30 02:20:51 -0500 |
commit | f27b135285d032d9570a1accb00412e111b38878 (patch) | |
tree | 73da0a490f55cec0518d92e007e132803e467565 /include | |
parent | 3bd4653767bb5eadd253e382fe8503ceb6bef5d1 (diff) |
Update bcachefs sources to 71a5b27e017d bcachefs: Make backpointer fsck wb flush check more rigorous
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/mean_and_variance.h | 198 |
1 files changed, 0 insertions, 198 deletions
diff --git a/include/linux/mean_and_variance.h b/include/linux/mean_and_variance.h deleted file mode 100644 index 64750501..00000000 --- a/include/linux/mean_and_variance.h +++ /dev/null @@ -1,198 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef MEAN_AND_VARIANCE_H_ -#define MEAN_AND_VARIANCE_H_ - -#include <linux/types.h> -#include <linux/limits.h> -#include <linux/math.h> -#include <linux/math64.h> - -#define SQRT_U64_MAX 4294967295ULL - -/* - * u128_u: u128 user mode, because not all architectures support a real int128 - * type - */ - -#ifdef __SIZEOF_INT128__ - -typedef struct { - unsigned __int128 v; -} __aligned(16) u128_u; - -static inline u128_u u64_to_u128(u64 a) -{ - return (u128_u) { .v = a }; -} - -static inline u64 u128_lo(u128_u a) -{ - return a.v; -} - -static inline u64 u128_hi(u128_u a) -{ - return a.v >> 64; -} - -static inline u128_u u128_add(u128_u a, u128_u b) -{ - a.v += b.v; - return a; -} - -static inline u128_u u128_sub(u128_u a, u128_u b) -{ - a.v -= b.v; - return a; -} - -static inline u128_u u128_shl(u128_u a, s8 shift) -{ - a.v <<= shift; - return a; -} - -static inline u128_u u128_square(u64 a) -{ - u128_u b = u64_to_u128(a); - - b.v *= b.v; - return b; -} - -#else - -typedef struct { - u64 hi, lo; -} __aligned(16) u128_u; - -/* conversions */ - -static inline u128_u u64_to_u128(u64 a) -{ - return (u128_u) { .lo = a }; -} - -static inline u64 u128_lo(u128_u a) -{ - return a.lo; -} - -static inline u64 u128_hi(u128_u a) -{ - return a.hi; -} - -/* arithmetic */ - -static inline u128_u u128_add(u128_u a, u128_u b) -{ - u128_u c; - - c.lo = a.lo + b.lo; - c.hi = a.hi + b.hi + (c.lo < a.lo); - return c; -} - -static inline u128_u u128_sub(u128_u a, u128_u b) -{ - u128_u c; - - c.lo = a.lo - b.lo; - c.hi = a.hi - b.hi - (c.lo > a.lo); - return c; -} - -static inline u128_u u128_shl(u128_u i, s8 shift) -{ - u128_u r; - - r.lo = i.lo << shift; - if (shift < 64) - r.hi = (i.hi << shift) | (i.lo >> (64 - shift)); - else { - r.hi = i.lo << (shift - 64); - r.lo = 0; - } - return r; -} - -static inline u128_u u128_square(u64 i) -{ - u128_u r; - u64 h = i >> 32, l = i & U32_MAX; - - r = u128_shl(u64_to_u128(h*h), 64); - r = u128_add(r, u128_shl(u64_to_u128(h*l), 32)); - r = u128_add(r, u128_shl(u64_to_u128(l*h), 32)); - r = u128_add(r, u64_to_u128(l*l)); - return r; -} - -#endif - -static inline u128_u u64s_to_u128(u64 hi, u64 lo) -{ - u128_u c = u64_to_u128(hi); - - c = u128_shl(c, 64); - c = u128_add(c, u64_to_u128(lo)); - return c; -} - -u128_u u128_div(u128_u n, u64 d); - -struct mean_and_variance { - s64 n; - s64 sum; - u128_u sum_squares; -}; - -/* expontentially weighted variant */ -struct mean_and_variance_weighted { - bool init; - u8 weight; /* base 2 logarithim */ - s64 mean; - u64 variance; -}; - -/** - * fast_divpow2() - fast approximation for n / (1 << d) - * @n: numerator - * @d: the power of 2 denominator. - * - * note: this rounds towards 0. - */ -static inline s64 fast_divpow2(s64 n, u8 d) -{ - return (n + ((n < 0) ? ((1 << d) - 1) : 0)) >> d; -} - -/** - * mean_and_variance_update() - update a mean_and_variance struct @s1 with a new sample @v1 - * and return it. - * @s1: the mean_and_variance to update. - * @v1: the new sample. - * - * see linked pdf equation 12. - */ -static inline void -mean_and_variance_update(struct mean_and_variance *s, s64 v) -{ - s->n++; - s->sum += v; - s->sum_squares = u128_add(s->sum_squares, u128_square(abs(v))); -} - -s64 mean_and_variance_get_mean(struct mean_and_variance s); -u64 mean_and_variance_get_variance(struct mean_and_variance s1); -u32 mean_and_variance_get_stddev(struct mean_and_variance s); - -void mean_and_variance_weighted_update(struct mean_and_variance_weighted *s, s64 v); - -s64 mean_and_variance_weighted_get_mean(struct mean_and_variance_weighted s); -u64 mean_and_variance_weighted_get_variance(struct mean_and_variance_weighted s); -u32 mean_and_variance_weighted_get_stddev(struct mean_and_variance_weighted s); - -#endif // MEAN_AND_VAIRANCE_H_ |