From 8d2b18793d16e4186f00b07d031a25537c4cefb9 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 12 Mar 2015 14:49:38 +1100 Subject: rhashtable: Move masking back into key_hashfn This patch reverts commit c88455ce50ae4224d84960ce2baa53e61580df27 ("rhashtable: key_hashfn() must return full hash value") because the only user of it always masks the hash value. Signed-off-by: Herbert Xu Acked-by: Thomas Graf Signed-off-by: David S. Miller --- lib/rhashtable.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/lib/rhashtable.c b/lib/rhashtable.c index d7f3db57b5d0..ff9cc3386fc9 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -83,7 +83,8 @@ static u32 obj_raw_hashfn(struct rhashtable *ht, static u32 key_hashfn(struct rhashtable *ht, const struct bucket_table *tbl, const void *key, u32 len) { - return ht->p.hashfn(key, len, tbl->hash_rnd) >> HASH_RESERVED_SPACE; + return rht_bucket_index(tbl, ht->p.hashfn(key, len, tbl->hash_rnd) >> + HASH_RESERVED_SPACE); } static u32 head_hashfn(struct rhashtable *ht, @@ -622,7 +623,7 @@ void *rhashtable_lookup_compare(struct rhashtable *ht, const void *key, tbl = rht_dereference_rcu(ht->tbl, ht); hash = key_hashfn(ht, tbl, key, ht->p.key_len); restart: - rht_for_each_rcu(he, tbl, rht_bucket_index(tbl, hash)) { + rht_for_each_rcu(he, tbl, hash) { if (!compare(rht_obj(ht, he), arg)) continue; rcu_read_unlock(); -- cgit v1.2.3 From eca849333017cab1cd02c8fc9187962fa629b27d Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 12 Mar 2015 14:49:39 +1100 Subject: rhashtable: Use head_hashfn instead of obj_raw_hashfn Now that we don't have cross-table hashes, we no longer need to keep the entire hash value so all users of obj_raw_hashfn can use head_hashfn instead. Signed-off-by: Herbert Xu Acked-by: Thomas Graf Signed-off-by: David S. Miller --- lib/rhashtable.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/lib/rhashtable.c b/lib/rhashtable.c index ff9cc3386fc9..03fdaf869c4d 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -403,7 +403,7 @@ static bool __rhashtable_insert(struct rhashtable *ht, struct rhash_head *obj, rcu_read_lock(); old_tbl = rht_dereference_rcu(ht->tbl, ht); - hash = obj_raw_hashfn(ht, old_tbl, rht_obj(ht, obj)); + hash = head_hashfn(ht, old_tbl, obj); spin_lock_bh(bucket_lock(old_tbl, hash)); @@ -415,7 +415,7 @@ static bool __rhashtable_insert(struct rhashtable *ht, struct rhash_head *obj, */ tbl = rht_dereference_rcu(ht->future_tbl, ht); if (tbl != old_tbl) { - hash = obj_raw_hashfn(ht, tbl, rht_obj(ht, obj)); + hash = head_hashfn(ht, tbl, obj); spin_lock_nested(bucket_lock(tbl, hash), RHT_LOCK_NESTED); } @@ -428,7 +428,6 @@ static bool __rhashtable_insert(struct rhashtable *ht, struct rhash_head *obj, no_resize_running = tbl == old_tbl; - hash = rht_bucket_index(tbl, hash); head = rht_dereference_bucket(tbl->buckets[hash], tbl, hash); if (rht_is_a_nulls(head)) @@ -444,11 +443,11 @@ static bool __rhashtable_insert(struct rhashtable *ht, struct rhash_head *obj, exit: if (tbl != old_tbl) { - hash = obj_raw_hashfn(ht, tbl, rht_obj(ht, obj)); + hash = head_hashfn(ht, tbl, obj); spin_unlock(bucket_lock(tbl, hash)); } - hash = obj_raw_hashfn(ht, old_tbl, rht_obj(ht, obj)); + hash = head_hashfn(ht, old_tbl, obj); spin_unlock_bh(bucket_lock(old_tbl, hash)); rcu_read_unlock(); @@ -487,9 +486,8 @@ static bool __rhashtable_remove(struct rhashtable *ht, unsigned hash; bool ret = false; - hash = obj_raw_hashfn(ht, tbl, rht_obj(ht, obj)); + hash = head_hashfn(ht, tbl, obj); lock = bucket_lock(tbl, hash); - hash = rht_bucket_index(tbl, hash); spin_lock_bh(lock); -- cgit v1.2.3 From cffaa9cb922472936b269017afdd3f147cb6f380 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 12 Mar 2015 14:49:40 +1100 Subject: rhashtable: Remove key length argument to key_hashfn key_hashfn has only one caller and it doesn't really need to supply the key length as an extra parameter. Signed-off-by: Herbert Xu Acked-by: Thomas Graf Signed-off-by: David S. Miller --- lib/rhashtable.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 03fdaf869c4d..838cccc4ef7e 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -81,9 +81,10 @@ static u32 obj_raw_hashfn(struct rhashtable *ht, } static u32 key_hashfn(struct rhashtable *ht, const struct bucket_table *tbl, - const void *key, u32 len) + const void *key) { - return rht_bucket_index(tbl, ht->p.hashfn(key, len, tbl->hash_rnd) >> + return rht_bucket_index(tbl, ht->p.hashfn(key, ht->p.key_len, + tbl->hash_rnd) >> HASH_RESERVED_SPACE); } @@ -619,7 +620,7 @@ void *rhashtable_lookup_compare(struct rhashtable *ht, const void *key, rcu_read_lock(); tbl = rht_dereference_rcu(ht->tbl, ht); - hash = key_hashfn(ht, tbl, key, ht->p.key_len); + hash = key_hashfn(ht, tbl, key); restart: rht_for_each_rcu(he, tbl, hash) { if (!compare(rht_obj(ht, he), arg)) -- cgit v1.2.3 From ec9f71c59e00388efc1337307511b59cc4c48394 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 12 Mar 2015 14:49:41 +1100 Subject: rhashtable: Remove obj_raw_hashfn Now that the only caller of obj_raw_hashfn is head_hashfn, we can simply kill it and fold it into the latter. This patch also moves the common shift from head_hashfn/key_hashfn into rht_bucket_index. Signed-off-by: Herbert Xu Acked-by: Thomas Graf Signed-off-by: David S. Miller --- lib/rhashtable.c | 25 +++++++------------------ 1 file changed, 7 insertions(+), 18 deletions(-) diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 838cccc4ef7e..6ffc793145f3 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -63,36 +63,25 @@ static void *rht_obj(const struct rhashtable *ht, const struct rhash_head *he) static u32 rht_bucket_index(const struct bucket_table *tbl, u32 hash) { - return hash & (tbl->size - 1); -} - -static u32 obj_raw_hashfn(struct rhashtable *ht, - const struct bucket_table *tbl, const void *ptr) -{ - u32 hash; - - if (unlikely(!ht->p.key_len)) - hash = ht->p.obj_hashfn(ptr, tbl->hash_rnd); - else - hash = ht->p.hashfn(ptr + ht->p.key_offset, ht->p.key_len, - tbl->hash_rnd); - - return hash >> HASH_RESERVED_SPACE; + return (hash >> HASH_RESERVED_SPACE) & (tbl->size - 1); } static u32 key_hashfn(struct rhashtable *ht, const struct bucket_table *tbl, const void *key) { return rht_bucket_index(tbl, ht->p.hashfn(key, ht->p.key_len, - tbl->hash_rnd) >> - HASH_RESERVED_SPACE); + tbl->hash_rnd)); } static u32 head_hashfn(struct rhashtable *ht, const struct bucket_table *tbl, const struct rhash_head *he) { - return rht_bucket_index(tbl, obj_raw_hashfn(ht, tbl, rht_obj(ht, he))); + const char *ptr = rht_obj(ht, he); + + return likely(ht->p.key_len) ? + key_hashfn(ht, tbl, ptr + ht->p.key_offset) : + rht_bucket_index(tbl, ht->p.obj_hashfn(ptr, tbl->hash_rnd)); } #ifdef CONFIG_PROVE_LOCKING -- cgit v1.2.3