diff options
| author | Thomas Graf <tgraf@suug.ch> | 2015-03-16 10:42:26 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-03-16 17:14:34 -0400 |
| commit | 617011e7d5559046e4fc8f87793c8a5d9c3431b0 (patch) | |
| tree | 43dc9257e68f0bb7c5a3ce132932ecf632654d22 | |
| parent | 9f1ab18672bee992b6169bbfa2b5ae86b42e88a8 (diff) | |
rhashtable: Avoid calculating hash again to unlock
Caching the lock pointer avoids having to hash on the object
again to unlock the bucket locks.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | lib/rhashtable.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/lib/rhashtable.c b/lib/rhashtable.c index eae26a67bd18..09a7ada89ade 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -384,14 +384,16 @@ static bool __rhashtable_insert(struct rhashtable *ht, struct rhash_head *obj, struct rhash_head *head; bool no_resize_running; unsigned hash; + spinlock_t *old_lock; bool success = true; rcu_read_lock(); old_tbl = rht_dereference_rcu(ht->tbl, ht); hash = head_hashfn(ht, old_tbl, obj); + old_lock = bucket_lock(old_tbl, hash); - spin_lock_bh(bucket_lock(old_tbl, hash)); + spin_lock_bh(old_lock); /* Because we have already taken the bucket lock in old_tbl, * if we find that future_tbl is not yet visible then that @@ -428,13 +430,10 @@ static bool __rhashtable_insert(struct rhashtable *ht, struct rhash_head *obj, schedule_work(&ht->run_work); exit: - if (tbl != old_tbl) { - hash = head_hashfn(ht, tbl, obj); + if (tbl != old_tbl) spin_unlock(bucket_lock(tbl, hash)); - } - hash = head_hashfn(ht, old_tbl, obj); - spin_unlock_bh(bucket_lock(old_tbl, hash)); + spin_unlock_bh(old_lock); rcu_read_unlock(); |