bcache: Don't touch bucket gen for dirty ptrs

Unnecessary since a bucket that has dirty pointers pointing to it can
never be invalidated - and skipping it is a measurable performance
boost, since the bucket gen will usually be a cache miss.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This commit is contained in:
Kent Overstreet 2013-08-09 21:14:13 -07:00
parent b0f32a56f2
commit d56d000a1f
2 changed files with 7 additions and 2 deletions

View File

@ -176,10 +176,14 @@ bool bch_ptr_bad(struct btree *b, const struct bkey *k)
bch_ptr_invalid(b, k))
return true;
for (i = 0; i < KEY_PTRS(k); i++) {
for (i = 0; i < KEY_PTRS(k); i++)
if (!ptr_available(b->c, k, i))
return true;
if (!expensive_debug_checks(b->c) && KEY_DIRTY(k))
return false;
for (i = 0; i < KEY_PTRS(k); i++) {
g = PTR_BUCKET(b->c, k, i);
stale = ptr_stale(b->c, k, i);

View File

@ -630,7 +630,8 @@ static void bch_cache_read_endio(struct bio *bio, int error)
if (error)
s->iop.error = error;
else if (ptr_stale(s->iop.c, &b->key, 0)) {
else if (!KEY_DIRTY(&b->key) &&
ptr_stale(s->iop.c, &b->key, 0)) {
atomic_long_inc(&s->iop.c->cache_read_races);
s->iop.error = -EINTR;
}