From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ying Xue Subject: [PATCH net-next v2 1/7] rhashtable: optimize rhashtable_lookup routine Date: Wed, 7 Jan 2015 13:41:52 +0800 Message-ID: <1420609318-3261-2-git-send-email-ying.xue@windriver.com> References: <1420609318-3261-1-git-send-email-ying.xue@windriver.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: jon.maloy@ericsson.com, netdev@vger.kernel.org, Paul.Gortmaker@windriver.com, tipc-discussion@lists.sourceforge.net, davem@davemloft.net To: Return-path: In-Reply-To: <1420609318-3261-1-git-send-email-ying.xue@windriver.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tipc-discussion-bounces@lists.sourceforge.net List-Id: netdev.vger.kernel.org Define an internal compare function and relevant compare argument, and then make use of rhashtable_lookup_compare() to lookup key in hash table, reducing duplicated code between rhashtable_lookup() and rhashtable_lookup_compare(). Signed-off-by: Ying Xue Cc: Thomas Graf Acked-by: Thomas Graf --- lib/rhashtable.c | 41 ++++++++++++++++++----------------------- 1 file changed, 18 insertions(+), 23 deletions(-) diff --git a/lib/rhashtable.c b/lib/rhashtable.c index cbad192..f2fdd7a 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -612,6 +612,19 @@ restart: } EXPORT_SYMBOL_GPL(rhashtable_remove); +struct rhashtable_compare_arg { + struct rhashtable *ht; + const void *key; +}; + +static bool rhashtable_compare(void *ptr, void *arg) +{ + struct rhashtable_compare_arg *x = arg; + struct rhashtable *ht = x->ht; + + return !memcmp(ptr + ht->p.key_offset, x->key, ht->p.key_len); +} + /** * rhashtable_lookup - lookup key in hash table * @ht: hash table @@ -627,32 +640,14 @@ EXPORT_SYMBOL_GPL(rhashtable_remove); */ void *rhashtable_lookup(struct rhashtable *ht, const void *key) { - const struct bucket_table *tbl, *old_tbl; - struct rhash_head *he; - u32 hash; + struct rhashtable_compare_arg arg = { + .ht = ht, + .key = key, + }; BUG_ON(!ht->p.key_len); - rcu_read_lock(); - old_tbl = rht_dereference_rcu(ht->tbl, ht); - tbl = rht_dereference_rcu(ht->future_tbl, ht); - hash = key_hashfn(ht, key, ht->p.key_len); -restart: - rht_for_each_rcu(he, tbl, rht_bucket_index(tbl, hash)) { - if (memcmp(rht_obj(ht, he) + ht->p.key_offset, key, - ht->p.key_len)) - continue; - rcu_read_unlock(); - return rht_obj(ht, he); - } - - if (unlikely(tbl != old_tbl)) { - tbl = old_tbl; - goto restart; - } - - rcu_read_unlock(); - return NULL; + return rhashtable_lookup_compare(ht, key, &rhashtable_compare, &arg); } EXPORT_SYMBOL_GPL(rhashtable_lookup); -- 1.7.9.5 ------------------------------------------------------------------------------ Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net