bcachefs: Kill unnecessary bch2_dev_usage_read()

Kent Overstreet · Kent Overstreet · commit d8bdc8daac1d · 2025-03-24T09:50:37.000-04:00
bch2_dev_usage_read() is fairly expensive, we should optimize this more.

Signed-off-by: Kent Overstreet &lt;kent.overstreet@linux.dev&gt;
diff --git a/fs/bcachefs/alloc_foreground.c b/fs/bcachefs/alloc_foreground.c
@@ -631,7 +631,7 @@ static inline void bch2_dev_stripe_increment_inlined(struct bch_dev *ca,
 			       struct bch_dev_usage *usage)
 {
 	u64 *v = stripe->next_alloc + ca->dev_idx;
-	u64 free_space = dev_buckets_available(ca, BCH_WATERMARK_normal);
+	u64 free_space = __dev_buckets_available(ca, *usage, BCH_WATERMARK_normal);
 	u64 free_space_inv = free_space
 		? div64_u64(1ULL << 48, free_space)
 		: 1ULL << 48;

Original file line number	Diff line number	Diff line change
`@@ -631,7 +631,7 @@ static inline void bch2_dev_stripe_increment_inlined(struct bch_dev *ca,`
`631`	`631`	`struct bch_dev_usage *usage)`
`632`	`632`	`{`
`633`	`633`	`u64 *v = stripe->next_alloc + ca->dev_idx;`
`634`		`- u64 free_space = dev_buckets_available(ca, BCH_WATERMARK_normal);`
	`634`	`+ u64 free_space = __dev_buckets_available(ca, *usage, BCH_WATERMARK_normal);`
`635`	`635`	`u64 free_space_inv = free_space`
`636`	`636`	`? div64_u64(1ULL << 48, free_space)`
`637`	`637`	`: 1ULL << 48;`