Update bcachefs sources to 5963d1b1a4 bcacehfs: Fix bch2_get_alloc_in_memory_pos()

1 files changed, 40 insertions, 0 deletions

diff --git a/include/linux/mean_and_variance.h b/include/linux/mean_and_variance.h
index cbac6ac8..b7fa5e96 100644
--- a/include/linux/mean_and_variance.h
+++ b/include/linux/mean_and_variance.h
@@ -157,6 +157,46 @@ struct mean_and_variance_weighted {
 
 s64 fast_divpow2(s64 n, u8 d);
 
+static inline struct mean_and_variance
+mean_and_variance_update_inlined(struct mean_and_variance s1, s64 v1)
+{
+	struct mean_and_variance s2;
+	u64 v2 = abs(v1);
+
+	s2.n           = s1.n + 1;
+	s2.sum         = s1.sum + v1;
+	s2.sum_squares = u128_add(s1.sum_squares, u128_square(v2));
+	return s2;
+}
+
+static inline struct mean_and_variance_weighted
+mean_and_variance_weighted_update_inlined(struct mean_and_variance_weighted s1, s64 x)
+{
+	struct mean_and_variance_weighted s2;
+	// previous weighted variance.
+	u64 var_w0 = s1.variance;
+	u8 w = s2.w = s1.w;
+	// new value weighted.
+	s64 x_w = x << w;
+	s64 diff_w = x_w - s1.mean;
+	s64 diff = fast_divpow2(diff_w, w);
+	// new mean weighted.
+	s64 u_w1     = s1.mean + diff;
+
+	BUG_ON(w % 2 != 0);
+
+	if (!s1.init) {
+		s2.mean = x_w;
+		s2.variance = 0;
+	} else {
+		s2.mean = u_w1;
+		s2.variance = ((var_w0 << w) - var_w0 + ((diff_w * (x_w - u_w1)) >> w)) >> w;
+	}
+	s2.init = true;
+
+	return s2;
+}
+
 struct mean_and_variance mean_and_variance_update(struct mean_and_variance s1, s64 v1);
        s64		 mean_and_variance_get_mean(struct mean_and_variance s);
        u64		 mean_and_variance_get_variance(struct mean_and_variance s1);