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| author | Kent Overstreet <kent.overstreet@linux.dev> | 2022-10-21 14:01:19 -0400 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@linux.dev> | 2023-10-22 17:09:44 -0400 |
| commit | ed80c5699a23c4005ba8e81d4b8fb3e1b922fa40 (patch) | |
| tree | 3c2dd5e984480c39efbaa6ea19011bacbeec10d1 /fs/bcachefs/buckets.c | |
| parent | 2d485df3da368193dafc78be933669d427b7ddf7 (diff) | |
| download | lwn-ed80c5699a23c4005ba8e81d4b8fb3e1b922fa40.tar.gz lwn-ed80c5699a23c4005ba8e81d4b8fb3e1b922fa40.zip | |
bcachefs: Optimize bch2_dev_usage_read()
- add bch2_dev_usage_read_fast(), which doesn't return by value -
bch_dev_usage is big enough that we don't want the silent memcpy
- tweak the allocation path to only call bch2_dev_usage_read() once per
bucket allocated
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'fs/bcachefs/buckets.c')
| -rw-r--r-- | fs/bcachefs/buckets.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/fs/bcachefs/buckets.c b/fs/bcachefs/buckets.c index 5cb4a00166f9..1a1790ac01ae 100644 --- a/fs/bcachefs/buckets.c +++ b/fs/bcachefs/buckets.c @@ -88,20 +88,17 @@ static inline struct bch_dev_usage *dev_usage_ptr(struct bch_dev *ca, : ca->usage[journal_seq & JOURNAL_BUF_MASK]); } -struct bch_dev_usage bch2_dev_usage_read(struct bch_dev *ca) +void bch2_dev_usage_read_fast(struct bch_dev *ca, struct bch_dev_usage *usage) { struct bch_fs *c = ca->fs; - struct bch_dev_usage ret; unsigned seq, i, u64s = dev_usage_u64s(); do { seq = read_seqcount_begin(&c->usage_lock); - memcpy(&ret, ca->usage_base, u64s * sizeof(u64)); + memcpy(usage, ca->usage_base, u64s * sizeof(u64)); for (i = 0; i < ARRAY_SIZE(ca->usage); i++) - acc_u64s_percpu((u64 *) &ret, (u64 __percpu *) ca->usage[i], u64s); + acc_u64s_percpu((u64 *) usage, (u64 __percpu *) ca->usage[i], u64s); } while (read_seqcount_retry(&c->usage_lock, seq)); - - return ret; } static inline struct bch_fs_usage *fs_usage_ptr(struct bch_fs *c, |