From 6aebd940840a4d3a0a8ffc5883d3892f4bd61e90 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 18 Mar 2015 20:01:15 +1100 Subject: [PATCH 1/6] rhashtable: Remove shift from bucket_table Keeping both size and shift is silly. We only need one. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- include/linux/rhashtable.h | 2 -- lib/rhashtable.c | 5 ++--- 2 files changed, 2 insertions(+), 5 deletions(-) diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h index 1695378b3c5b..f16e85692959 100644 --- a/include/linux/rhashtable.h +++ b/include/linux/rhashtable.h @@ -51,7 +51,6 @@ struct rhash_head { * @size: Number of hash buckets * @rehash: Current bucket being rehashed * @hash_rnd: Random seed to fold into hash - * @shift: Current size (1 << shift) * @locks_mask: Mask to apply before accessing locks[] * @locks: Array of spinlocks protecting individual buckets * @walkers: List of active walkers @@ -63,7 +62,6 @@ struct bucket_table { unsigned int size; unsigned int rehash; u32 hash_rnd; - u32 shift; unsigned int locks_mask; spinlock_t *locks; struct list_head walkers; diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 09a7ada89ade..097400362467 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -162,7 +162,6 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht, return NULL; tbl->size = nbuckets; - tbl->shift = ilog2(nbuckets); if (alloc_bucket_locks(ht, tbl) < 0) { bucket_table_free(tbl); @@ -189,7 +188,7 @@ static bool rht_grow_above_75(const struct rhashtable *ht, { /* Expand table when exceeding 75% load */ return atomic_read(&ht->nelems) > (tbl->size / 4 * 3) && - (!ht->p.max_shift || tbl->shift < ht->p.max_shift); + (!ht->p.max_shift || tbl->size < (1 << ht->p.max_shift)); } /** @@ -202,7 +201,7 @@ static bool rht_shrink_below_30(const struct rhashtable *ht, { /* Shrink table beneath 30% load */ return atomic_read(&ht->nelems) < (tbl->size * 3 / 10) && - tbl->shift > ht->p.min_shift; + tbl->size > (1 << ht->p.min_shift); } static int rhashtable_rehash_one(struct rhashtable *ht, unsigned old_hash) From c2e213cff701fce71a0aba8de82f2c2a4acf52ae Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 18 Mar 2015 20:01:16 +1100 Subject: [PATCH 2/6] rhashtable: Introduce max_size/min_size This patch adds the parameters max_size and min_size which are meant to replace max_shift and min_shift. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- include/linux/rhashtable.h | 4 ++++ lib/rhashtable.c | 12 ++++++++---- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h index f16e85692959..81267fef85d7 100644 --- a/include/linux/rhashtable.h +++ b/include/linux/rhashtable.h @@ -85,6 +85,8 @@ struct rhashtable; * @head_offset: Offset of rhash_head in struct to be hashed * @max_shift: Maximum number of shifts while expanding * @min_shift: Minimum number of shifts while shrinking + * @max_size: Maximum size while expanding + * @min_size: Minimum size while shrinking * @nulls_base: Base value to generate nulls marker * @locks_mul: Number of bucket locks to allocate per cpu (default: 128) * @hashfn: Function to hash key @@ -97,6 +99,8 @@ struct rhashtable_params { size_t head_offset; size_t max_shift; size_t min_shift; + unsigned int max_size; + unsigned int min_size; u32 nulls_base; size_t locks_mul; rht_hashfn_t hashfn; diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 097400362467..c4061bbd0113 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -27,7 +27,7 @@ #include #define HASH_DEFAULT_SIZE 64UL -#define HASH_MIN_SIZE 4UL +#define HASH_MIN_SIZE 4U #define BUCKET_LOCKS_PER_CPU 128UL /* Base bits plus 1 bit for nulls marker */ @@ -188,7 +188,8 @@ static bool rht_grow_above_75(const struct rhashtable *ht, { /* Expand table when exceeding 75% load */ return atomic_read(&ht->nelems) > (tbl->size / 4 * 3) && - (!ht->p.max_shift || tbl->size < (1 << ht->p.max_shift)); + (!ht->p.max_shift || tbl->size < (1 << ht->p.max_shift)) && + (!ht->p.max_size || tbl->size < ht->p.max_size); } /** @@ -201,7 +202,8 @@ static bool rht_shrink_below_30(const struct rhashtable *ht, { /* Shrink table beneath 30% load */ return atomic_read(&ht->nelems) < (tbl->size * 3 / 10) && - tbl->size > (1 << ht->p.min_shift); + tbl->size > (1 << ht->p.min_shift) && + tbl->size > ht->p.min_size; } static int rhashtable_rehash_one(struct rhashtable *ht, unsigned old_hash) @@ -873,7 +875,8 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_stop); static size_t rounded_hashtable_size(struct rhashtable_params *params) { return max(roundup_pow_of_two(params->nelem_hint * 4 / 3), - 1UL << params->min_shift); + max(1UL << params->min_shift, + (unsigned long)params->min_size)); } /** @@ -935,6 +938,7 @@ int rhashtable_init(struct rhashtable *ht, struct rhashtable_params *params) params->min_shift = max_t(size_t, params->min_shift, ilog2(HASH_MIN_SIZE)); + params->min_size = max(params->min_size, HASH_MIN_SIZE); if (params->nelem_hint) size = rounded_hashtable_size(params); From b06eee59b1e547f0f401820388ca68c624298a64 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 18 Mar 2015 20:01:17 +1100 Subject: [PATCH 3/6] netlink: Use rhashtable max_size instead of max_shift This patch converts netlink to use rhashtable max_size instead of the obsolete max_shift. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/netlink/af_netlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 6b0f21950e09..d97aed628bda 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -3123,7 +3123,7 @@ static int __init netlink_proto_init(void) .key_offset = offsetof(struct netlink_sock, portid), .key_len = sizeof(u32), /* portid */ .hashfn = jhash, - .max_shift = 16, /* 64K */ + .max_size = 65536, }; if (err != 0) From 446c89ac1f6026df9e3e0ca2614b36909398d431 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 18 Mar 2015 20:01:18 +1100 Subject: [PATCH 4/6] tipc: Use rhashtable max/min_size instead of max/min_shift This patch converts tipc to use rhashtable max/min_size instead of the obsolete max/min_shift. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/tipc/socket.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/tipc/socket.c b/net/tipc/socket.c index 813847d25a49..d7a6c10202e9 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -2286,8 +2286,8 @@ int tipc_sk_rht_init(struct net *net) .key_offset = offsetof(struct tipc_sock, portid), .key_len = sizeof(u32), /* portid */ .hashfn = jhash, - .max_shift = 20, /* 1M */ - .min_shift = 8, /* 256 */ + .max_size = 1048576, + .min_size = 256, }; return rhashtable_init(&tn->sk_rht, &rht_params); From 4f509df4f50e72cba65c3b58241a17639b2d9b49 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 18 Mar 2015 20:01:19 +1100 Subject: [PATCH 5/6] test_rhashtable: Use rhashtable max_size instead of max_shift This patch converts test_rhashtable to use rhashtable max_size instead of the obsolete max_shift. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- lib/test_rhashtable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c index 16974fd89e4e..2bc403d8f9ee 100644 --- a/lib/test_rhashtable.c +++ b/lib/test_rhashtable.c @@ -201,7 +201,7 @@ static int __init test_rht_init(void) .key_offset = offsetof(struct test_obj, value), .key_len = sizeof(int), .hashfn = jhash, - .max_shift = 1, /* we expand/shrink manually here */ + .max_size = 2, /* we expand/shrink manually here */ .nulls_base = (3U << RHT_BASE_SHIFT), }; int err; From e2e21c1c5808e5dfd88d3606cd6386cf85f6f5b1 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 18 Mar 2015 20:01:21 +1100 Subject: [PATCH 6/6] rhashtable: Remove max_shift and min_shift Now that nobody uses max_shift and min_shift, we can safely remove them. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- include/linux/rhashtable.h | 4 ---- lib/rhashtable.c | 7 +------ 2 files changed, 1 insertion(+), 10 deletions(-) diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h index 81267fef85d7..99425f2be708 100644 --- a/include/linux/rhashtable.h +++ b/include/linux/rhashtable.h @@ -83,8 +83,6 @@ struct rhashtable; * @key_len: Length of key * @key_offset: Offset of key in struct to be hashed * @head_offset: Offset of rhash_head in struct to be hashed - * @max_shift: Maximum number of shifts while expanding - * @min_shift: Minimum number of shifts while shrinking * @max_size: Maximum size while expanding * @min_size: Minimum size while shrinking * @nulls_base: Base value to generate nulls marker @@ -97,8 +95,6 @@ struct rhashtable_params { size_t key_len; size_t key_offset; size_t head_offset; - size_t max_shift; - size_t min_shift; unsigned int max_size; unsigned int min_size; u32 nulls_base; diff --git a/lib/rhashtable.c b/lib/rhashtable.c index c4061bbd0113..5f8fe3e88219 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -188,7 +188,6 @@ static bool rht_grow_above_75(const struct rhashtable *ht, { /* Expand table when exceeding 75% load */ return atomic_read(&ht->nelems) > (tbl->size / 4 * 3) && - (!ht->p.max_shift || tbl->size < (1 << ht->p.max_shift)) && (!ht->p.max_size || tbl->size < ht->p.max_size); } @@ -202,7 +201,6 @@ static bool rht_shrink_below_30(const struct rhashtable *ht, { /* Shrink table beneath 30% load */ return atomic_read(&ht->nelems) < (tbl->size * 3 / 10) && - tbl->size > (1 << ht->p.min_shift) && tbl->size > ht->p.min_size; } @@ -875,8 +873,7 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_stop); static size_t rounded_hashtable_size(struct rhashtable_params *params) { return max(roundup_pow_of_two(params->nelem_hint * 4 / 3), - max(1UL << params->min_shift, - (unsigned long)params->min_size)); + (unsigned long)params->min_size); } /** @@ -936,8 +933,6 @@ int rhashtable_init(struct rhashtable *ht, struct rhashtable_params *params) if (params->nulls_base && params->nulls_base < (1U << RHT_BASE_SHIFT)) return -EINVAL; - params->min_shift = max_t(size_t, params->min_shift, - ilog2(HASH_MIN_SIZE)); params->min_size = max(params->min_size, HASH_MIN_SIZE); if (params->nelem_hint)