[lttng-dev] [PATCH 09/12] remove struct rcu_table
Lai Jiangshan
laijs at cn.fujitsu.com
Mon Nov 28 03:08:05 EST 2011
Signed-off-by: Lai Jiangshan <laijs at cn.fujitsu.com>
---
rculfhash.c | 107 +++++++++++++++++++++++++++-------------------------------
1 files changed, 50 insertions(+), 57 deletions(-)
diff --git a/rculfhash.c b/rculfhash.c
index 18cead3..8dc9c59 100644
--- a/rculfhash.c
+++ b/rculfhash.c
@@ -240,36 +240,14 @@ struct ht_items_count {
} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
/*
- * rcu_table: Contains the size and desired new size if a resize
- * operation is in progress, as well as the statically-sized array of
- * bucket table pointers.
- */
-struct rcu_table {
- unsigned long size; /* always a power of 2, shared (RCU) */
- unsigned long resize_target;
- int resize_initiated;
-
- /*
- * Contains the per order-index-level bucket node table. The size
- * of each bucket node table is half the number of hashes contained
- * in this order (except for order 0). The minimum allocation size
- * parameter allows combining the bucket node arrays of the lowermost
- * levels to improve cache locality for small index orders.
- */
- struct cds_lfht_node *tbl[MAX_TABLE_ORDER];
-};
-
-/*
* cds_lfht: Top-level data structure representing a lock-free hash
* table. Defined in the implementation file to make it be an opaque
* cookie to users.
*/
struct cds_lfht {
- struct rcu_table t;
- unsigned long min_alloc_buckets_order;
- unsigned long min_nr_alloc_buckets;
- unsigned long max_nr_buckets;
+ unsigned long size; /* always a power of 2, shared (RCU) */
int flags;
+
/*
* We need to put the work threads offline (QSBR) when taking this
* mutex, because we use synchronize_rcu within this mutex critical
@@ -278,11 +256,26 @@ struct cds_lfht {
* completion.
*/
pthread_mutex_t resize_mutex; /* resize mutex: add/del mutex */
+ pthread_attr_t *resize_attr; /* Resize threads attributes */
unsigned int in_progress_resize, in_progress_destroy;
+ unsigned long resize_target;
+ int resize_initiated;
const struct rcu_flavor_struct *flavor;
- pthread_attr_t *resize_attr; /* Resize threads attributes */
+
long count; /* global approximate item count */
struct ht_items_count *split_count; /* split item count */
+
+ unsigned long min_alloc_buckets_order;
+ unsigned long min_nr_alloc_buckets;
+ unsigned long max_nr_buckets;
+ /*
+ * Contains the per order-index-level bucket node table. The size
+ * of each bucket node table is half the number of hashes contained
+ * in this order (except for order 0). The minimum allocation size
+ * parameter allows combining the bucket node arrays of the lowermost
+ * levels to improve cache locality for small index orders.
+ */
+ struct cds_lfht_node *tbl[MAX_TABLE_ORDER];
};
/*
@@ -751,13 +744,13 @@ static
void cds_lfht_alloc_bucket_table(struct cds_lfht *ht, unsigned long order)
{
if (order == 0) {
- ht->t.tbl[0] = calloc(ht->min_nr_alloc_buckets,
+ ht->tbl[0] = calloc(ht->min_nr_alloc_buckets,
sizeof(struct cds_lfht_node));
- assert(ht->t.tbl[0]);
+ assert(ht->tbl[0]);
} else if (order > ht->min_alloc_buckets_order) {
- ht->t.tbl[order] = calloc(1UL << (order -1),
+ ht->tbl[order] = calloc(1UL << (order -1),
sizeof(struct cds_lfht_node));
- assert(ht->t.tbl[order]);
+ assert(ht->tbl[order]);
}
/* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
}
@@ -771,9 +764,9 @@ static
void cds_lfht_free_bucket_table(struct cds_lfht *ht, unsigned long order)
{
if (order == 0)
- poison_free(ht->t.tbl[0]);
+ poison_free(ht->tbl[0]);
else if (order > ht->min_alloc_buckets_order)
- poison_free(ht->t.tbl[order]);
+ poison_free(ht->tbl[order]);
/* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
}
@@ -785,7 +778,7 @@ struct cds_lfht_node *bucket_at(struct cds_lfht *ht, unsigned long index)
if ((__builtin_constant_p(index) && index == 0)
|| index < ht->min_nr_alloc_buckets) {
dbg_printf("bucket index %lu order 0 aridx 0\n", index);
- return &ht->t.tbl[0][index];
+ return &ht->tbl[0][index];
}
/*
* equivalent to get_count_order_ulong(index + 1), but optimizes
@@ -795,7 +788,7 @@ struct cds_lfht_node *bucket_at(struct cds_lfht *ht, unsigned long index)
order = fls_ulong(index);
dbg_printf("bucket index %lu order %lu aridx %lu\n",
index, order, index & ((1UL << (order - 1)) - 1));
- return &ht->t.tbl[order][index & ((1UL << (order - 1)) - 1)];
+ return &ht->tbl[order][index & ((1UL << (order - 1)) - 1)];
}
static inline
@@ -1177,7 +1170,7 @@ void init_table(struct cds_lfht *ht,
dbg_printf("init order %lu len: %lu\n", i, len);
/* Stop expand if the resize target changes under us */
- if (CMM_LOAD_SHARED(ht->t.resize_target) < (1UL << i))
+ if (CMM_LOAD_SHARED(ht->resize_target) < (1UL << i))
break;
cds_lfht_alloc_bucket_table(ht, i);
@@ -1192,7 +1185,7 @@ void init_table(struct cds_lfht *ht,
* Update table size.
*/
cmm_smp_wmb(); /* populate data before RCU size */
- CMM_STORE_SHARED(ht->t.size, 1UL << i);
+ CMM_STORE_SHARED(ht->size, 1UL << i);
dbg_printf("init new size: %lu\n", 1UL << i);
if (CMM_LOAD_SHARED(ht->in_progress_destroy))
@@ -1276,11 +1269,11 @@ void fini_table(struct cds_lfht *ht,
dbg_printf("fini order %lu len: %lu\n", i, len);
/* Stop shrink if the resize target changes under us */
- if (CMM_LOAD_SHARED(ht->t.resize_target) > (1UL << (i - 1)))
+ if (CMM_LOAD_SHARED(ht->resize_target) > (1UL << (i - 1)))
break;
cmm_smp_wmb(); /* populate data before RCU size */
- CMM_STORE_SHARED(ht->t.size, 1UL << (i - 1));
+ CMM_STORE_SHARED(ht->size, 1UL << (i - 1));
/*
* We need to wait for all add operations to reach Q.S. (and
@@ -1395,12 +1388,12 @@ struct cds_lfht *_cds_lfht_new(unsigned long init_size,
/* this mutex should not nest in read-side C.S. */
pthread_mutex_init(&ht->resize_mutex, NULL);
order = get_count_order_ulong(init_size);
- ht->t.resize_target = 1UL << order;
+ ht->resize_target = 1UL << order;
ht->min_nr_alloc_buckets = min_nr_alloc_buckets;
ht->min_alloc_buckets_order = get_count_order_ulong(min_nr_alloc_buckets);
ht->max_nr_buckets = max_nr_buckets;
cds_lfht_create_bucket(ht, 1UL << order);
- ht->t.size = 1UL << order;
+ ht->size = 1UL << order;
return ht;
}
@@ -1413,7 +1406,7 @@ void cds_lfht_lookup(struct cds_lfht *ht, unsigned long hash,
reverse_hash = bit_reverse_ulong(hash);
- size = rcu_dereference(ht->t.size);
+ size = rcu_dereference(ht->size);
bucket = lookup_bucket(ht, size, hash);
/* We can always skip the bucket node initially */
node = rcu_dereference(bucket->next);
@@ -1513,7 +1506,7 @@ void cds_lfht_add(struct cds_lfht *ht, unsigned long hash,
unsigned long size;
node->reverse_hash = bit_reverse_ulong((unsigned long) hash);
- size = rcu_dereference(ht->t.size);
+ size = rcu_dereference(ht->size);
_cds_lfht_add(ht, NULL, NULL, size, node, NULL, 0);
ht_count_add(ht, size, hash);
}
@@ -1528,7 +1521,7 @@ struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
struct cds_lfht_iter iter;
node->reverse_hash = bit_reverse_ulong((unsigned long) hash);
- size = rcu_dereference(ht->t.size);
+ size = rcu_dereference(ht->size);
_cds_lfht_add(ht, match, key, size, node, &iter, 0);
if (iter.node == node)
ht_count_add(ht, size, hash);
@@ -1545,7 +1538,7 @@ struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
struct cds_lfht_iter iter;
node->reverse_hash = bit_reverse_ulong((unsigned long) hash);
- size = rcu_dereference(ht->t.size);
+ size = rcu_dereference(ht->size);
for (;;) {
_cds_lfht_add(ht, match, key, size, node, &iter, 0);
if (iter.node == node) {
@@ -1563,7 +1556,7 @@ int cds_lfht_replace(struct cds_lfht *ht, struct cds_lfht_iter *old_iter,
{
unsigned long size;
- size = rcu_dereference(ht->t.size);
+ size = rcu_dereference(ht->size);
return _cds_lfht_replace(ht, size, old_iter->node, old_iter->next,
new_node);
}
@@ -1573,7 +1566,7 @@ int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_iter *iter)
unsigned long size, hash;
int ret;
- size = rcu_dereference(ht->t.size);
+ size = rcu_dereference(ht->size);
ret = _cds_lfht_del(ht, size, iter->node, 0);
if (!ret) {
hash = bit_reverse_ulong(iter->node->reverse_hash);
@@ -1600,7 +1593,7 @@ int cds_lfht_delete_bucket(struct cds_lfht *ht)
* size accessed without rcu_dereference because hash table is
* being destroyed.
*/
- size = ht->t.size;
+ size = ht->size;
/* Internal sanity check: all nodes left should be bucket */
for (i = 0; i < size; i++) {
node = bucket_at(ht, i);
@@ -1734,23 +1727,23 @@ void _do_cds_lfht_resize(struct cds_lfht *ht)
assert(uatomic_read(&ht->in_progress_resize));
if (CMM_LOAD_SHARED(ht->in_progress_destroy))
break;
- ht->t.resize_initiated = 1;
- old_size = ht->t.size;
- new_size = CMM_LOAD_SHARED(ht->t.resize_target);
+ ht->resize_initiated = 1;
+ old_size = ht->size;
+ new_size = CMM_LOAD_SHARED(ht->resize_target);
if (old_size < new_size)
_do_cds_lfht_grow(ht, old_size, new_size);
else if (old_size > new_size)
_do_cds_lfht_shrink(ht, old_size, new_size);
- ht->t.resize_initiated = 0;
+ ht->resize_initiated = 0;
/* write resize_initiated before read resize_target */
cmm_smp_mb();
- } while (ht->t.size != CMM_LOAD_SHARED(ht->t.resize_target));
+ } while (ht->size != CMM_LOAD_SHARED(ht->resize_target));
}
static
unsigned long resize_target_grow(struct cds_lfht *ht, unsigned long new_size)
{
- return _uatomic_xchg_monotonic_increase(&ht->t.resize_target, new_size);
+ return _uatomic_xchg_monotonic_increase(&ht->resize_target, new_size);
}
static
@@ -1759,13 +1752,13 @@ void resize_target_update_count(struct cds_lfht *ht,
{
count = max(count, MIN_TABLE_SIZE);
count = min(count, ht->max_nr_buckets);
- uatomic_set(&ht->t.resize_target, count);
+ uatomic_set(&ht->resize_target, count);
}
void cds_lfht_resize(struct cds_lfht *ht, unsigned long new_size)
{
resize_target_update_count(ht, new_size);
- CMM_STORE_SHARED(ht->t.resize_initiated, 1);
+ CMM_STORE_SHARED(ht->resize_initiated, 1);
ht->flavor->thread_offline();
pthread_mutex_lock(&ht->resize_mutex);
_do_cds_lfht_resize(ht);
@@ -1797,7 +1790,7 @@ void __cds_lfht_resize_lazy_launch(struct cds_lfht *ht)
/* Store resize_target before read resize_initiated */
cmm_smp_mb();
- if (!CMM_LOAD_SHARED(ht->t.resize_initiated)) {
+ if (!CMM_LOAD_SHARED(ht->resize_initiated)) {
uatomic_inc(&ht->in_progress_resize);
cmm_smp_mb(); /* increment resize count before load destroy */
if (CMM_LOAD_SHARED(ht->in_progress_destroy)) {
@@ -1807,7 +1800,7 @@ void __cds_lfht_resize_lazy_launch(struct cds_lfht *ht)
work = malloc(sizeof(*work));
work->ht = ht;
ht->flavor->update_call_rcu(&work->head, do_resize_cb);
- CMM_STORE_SHARED(ht->t.resize_initiated, 1);
+ CMM_STORE_SHARED(ht->resize_initiated, 1);
}
}
@@ -1845,7 +1838,7 @@ void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size,
for (;;) {
unsigned long s;
- s = uatomic_cmpxchg(&ht->t.resize_target, size, count);
+ s = uatomic_cmpxchg(&ht->resize_target, size, count);
if (s == size)
break; /* no resize needed */
if (s > size)
--
1.7.4.4
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