#include <urcu/arch.h>
#include <assert.h>
#include <urcu-pointer.h>
+#include <urcu/uatomic.h>
#include <stdint.h>
#include "rcuja-internal.h"
* child type.
*/
#define JA_TYPE_BITS 3
-#define JA_TYPE_MAX_NR (1U << JA_TYPE_BITS)
+#define JA_TYPE_MAX_NR (1UL << JA_TYPE_BITS)
#define JA_TYPE_MASK (JA_TYPE_MAX_NR - 1)
#define JA_PTR_MASK (~JA_TYPE_MASK)
#define JA_ENTRY_PER_NODE 256UL
-#define JA_BITS_PER_BYTE 3
+#define JA_LOG2_BITS_PER_BYTE 3U
+#define JA_BITS_PER_BYTE (1U << JA_LOG2_BITS_PER_BYTE)
-#define JA_MAX_INTERNAL_DEPTH 5 /* Maximum depth, excluding leafs */
+#define JA_MAX_DEPTH 9 /* Maximum depth, including leafs */
/*
* Entry for NULL node is at index 8 of the table. It is never encoded
*/
#define NODE_INDEX_NULL 8
+/*
+ * Number of removals needed on a fallback node before we try to shrink
+ * it.
+ */
+#define JA_FALLBACK_REMOVAL_COUNT 8
+
/*
* Iteration on the array to find the right node size for the number of
* children stops when it reaches .max_child == 256 (this is the largest
} u;
};
+enum ja_recompact {
+ JA_RECOMPACT,
+ JA_RECOMPACT_ADD,
+ JA_RECOMPACT_DEL,
+};
+
static
struct cds_ja_inode_flag *ja_node_flag(struct cds_ja_inode *node,
- unsigned int type)
+ unsigned long type)
{
- assert(type < RCU_JA_NR_TYPES);
+ assert(type < (1UL << JA_TYPE_BITS));
return (struct cds_ja_inode_flag *) (((unsigned long) node) | type);
}
static
struct cds_ja_inode *ja_node_ptr(struct cds_ja_inode_flag *node)
{
- return (struct cds_ja_inode *) (((unsigned long) node) | JA_PTR_MASK);
+ return (struct cds_ja_inode *) (((unsigned long) node) & JA_PTR_MASK);
}
static
-unsigned int ja_node_type(struct cds_ja_inode_flag *node)
+unsigned long ja_node_type(struct cds_ja_inode_flag *node)
{
- unsigned int type;
+ unsigned long type;
if (ja_node_ptr(node) == NULL) {
return NODE_INDEX_NULL;
}
type = (unsigned int) ((unsigned long) node & JA_TYPE_MASK);
- assert(type < RCU_JA_NR_TYPES);
+ assert(type < (1UL << JA_TYPE_BITS));
return type;
}
struct cds_ja_inode *node)
{
assert(type->type_class == RCU_JA_LINEAR || type->type_class == RCU_JA_POOL);
- return CMM_LOAD_SHARED(node->u.data[0]);
+ return rcu_dereference(node->u.data[0]);
}
/*
if (i >= nr_child)
return NULL;
pointers = (struct cds_ja_inode_flag **) align_ptr_size(&values[type->max_linear_child]);
- if (caa_unlikely(child_node_flag_ptr))
- *child_node_flag_ptr = &pointers[i];
ptr = rcu_dereference(pointers[i]);
- assert(ja_node_ptr(ptr) != NULL);
+ if (caa_unlikely(child_node_flag_ptr) && ptr)
+ *child_node_flag_ptr = &pointers[i];
return ptr;
}
assert(type->type_class == RCU_JA_PIGEON);
child_node_flag = &((struct cds_ja_inode_flag **) node->u.data)[n];
- if (caa_unlikely(child_node_flag_ptr))
+ dbg_printf("ja_pigeon_node_get_nth child_node_flag_ptr %p\n",
+ child_node_flag);
+ if (caa_unlikely(child_node_flag_ptr) && *child_node_flag)
*child_node_flag_ptr = child_node_flag;
return rcu_dereference(*child_node_flag);
}
+static
+struct cds_ja_inode_flag *ja_pigeon_node_get_ith_pos(const struct cds_ja_type *type,
+ struct cds_ja_inode *node,
+ uint8_t i)
+{
+ return ja_pigeon_node_get_nth(type, node, NULL, i);
+}
+
/*
* ja_node_get_nth: get nth item from a node.
* node_flag is already rcu_dereference'd.
}
}
-/*
- * TODO: use ja_get_nr_child to monitor limits triggering shrink
- * recompaction.
- * Also use ja_get_nr_child to make the difference between resize and
- * pool change of compaction bit(s).
- */
-static
-unsigned int ja_get_nr_child(struct cds_ja_shadow_node *shadow_node)
-{
- return shadow_node->nr_child;
-}
-
static
int ja_linear_node_set_nth(const struct cds_ja_type *type,
struct cds_ja_inode *node,
uint8_t nr_child;
uint8_t *values, *nr_child_ptr;
struct cds_ja_inode_flag **pointers;
- unsigned int i;
+ unsigned int i, unused = 0;
assert(type->type_class == RCU_JA_LINEAR || type->type_class == RCU_JA_POOL);
nr_child_ptr = &node->u.data[0];
+ dbg_printf("linear set nth: nr_child_ptr %p\n", nr_child_ptr);
nr_child = *nr_child_ptr;
assert(nr_child <= type->max_linear_child);
- assert(type->type_class != RCU_JA_LINEAR || nr_child >= type->min_child);
values = &node->u.data[1];
+ pointers = (struct cds_ja_inode_flag **) align_ptr_size(&values[type->max_linear_child]);
+ /* Check if node value is already populated */
for (i = 0; i < nr_child; i++) {
- if (values[i] == n)
- return -EEXIST;
+ if (values[i] == n) {
+ if (pointers[i])
+ return -EEXIST;
+ else
+ break;
+ } else {
+ if (!pointers[i])
+ unused++;
+ }
}
- if (nr_child >= type->max_linear_child) {
- /* No space left in this node type */
- return -ENOSPC;
+ if (i == nr_child && nr_child >= type->max_linear_child) {
+ if (unused)
+ return -ERANGE; /* recompact node */
+ else
+ return -ENOSPC; /* No space left in this node type */
+ }
+
+ assert(pointers[i] == NULL);
+ rcu_assign_pointer(pointers[i], child_node_flag);
+ /* If we expanded the nr_child, increment it */
+ if (i == nr_child) {
+ CMM_STORE_SHARED(values[nr_child], n);
+ /* write pointer and value before nr_child */
+ cmm_smp_wmb();
+ CMM_STORE_SHARED(*nr_child_ptr, nr_child + 1);
}
- pointers = (struct cds_ja_inode_flag **) align_ptr_size(&values[type->max_linear_child]);
- assert(pointers[nr_child] == NULL);
- rcu_assign_pointer(pointers[nr_child], child_node_flag);
- CMM_STORE_SHARED(values[nr_child], n);
- cmm_smp_wmb(); /* write value and pointer before nr_child */
- CMM_STORE_SHARED(*nr_child_ptr, nr_child + 1);
shadow_node->nr_child++;
+ dbg_printf("linear set nth: %u child, shadow: %u child, for node %p shadow %p\n",
+ (unsigned int) CMM_LOAD_SHARED(*nr_child_ptr),
+ (unsigned int) shadow_node->nr_child,
+ node, shadow_node);
+
return 0;
}
/*
* _ja_node_set_nth: set nth item within a node. Return an error
* (negative error value) if it is already there.
- * TODO: exclusive access on node.
*/
static
int _ja_node_set_nth(const struct cds_ja_type *type,
return 0;
}
+static
+int ja_linear_node_clear_nth(const struct cds_ja_type *type,
+ struct cds_ja_inode *node,
+ struct cds_ja_shadow_node *shadow_node,
+ uint8_t n)
+{
+ uint8_t nr_child;
+ uint8_t *values, *nr_child_ptr;
+ struct cds_ja_inode_flag **pointers;
+ unsigned int i;
+
+ assert(type->type_class == RCU_JA_LINEAR || type->type_class == RCU_JA_POOL);
+
+ nr_child_ptr = &node->u.data[0];
+ dbg_printf("linear clear nth: nr_child_ptr %p\n", nr_child_ptr);
+ nr_child = *nr_child_ptr;
+ assert(nr_child <= type->max_linear_child);
+
+ values = &node->u.data[1];
+ pointers = (struct cds_ja_inode_flag **) align_ptr_size(&values[type->max_linear_child]);
+ for (i = 0; i < nr_child; i++) {
+ if (values[i] == n) {
+ if (pointers[i])
+ break;
+ else
+ return -ENOENT;
+ }
+ }
+ if (i >= nr_child)
+ return -ENOENT;
+ if (shadow_node->fallback_removal_count) {
+ shadow_node->fallback_removal_count--;
+ } else {
+ if (shadow_node->nr_child <= type->min_child) {
+ /* We need to try recompacting the node */
+ return -EFBIG;
+ }
+ }
+ assert(pointers[i] != NULL);
+ rcu_assign_pointer(pointers[i], NULL);
+ /*
+ * Value and nr_child are never changed (would cause ABA issue).
+ * Instead, we leave the pointer to NULL and recompact the node
+ * once in a while. It is allowed to set a NULL pointer to a new
+ * value without recompaction though.
+ * Only update the shadow node accounting.
+ */
+ shadow_node->nr_child--;
+ dbg_printf("linear set nth: %u child, shadow: %u child, for node %p shadow %p\n",
+ (unsigned int) CMM_LOAD_SHARED(*nr_child_ptr),
+ (unsigned int) shadow_node->nr_child,
+ node, shadow_node);
+
+ return 0;
+}
+
+static
+int ja_pool_node_clear_nth(const struct cds_ja_type *type,
+ struct cds_ja_inode *node,
+ struct cds_ja_shadow_node *shadow_node,
+ uint8_t n)
+{
+ struct cds_ja_inode *linear;
+
+ assert(type->type_class == RCU_JA_POOL);
+ linear = (struct cds_ja_inode *)
+ &node->u.data[((unsigned long) n >> (CHAR_BIT - type->nr_pool_order)) << type->pool_size_order];
+ return ja_linear_node_clear_nth(type, linear, shadow_node, n);
+}
+
+static
+int ja_pigeon_node_clear_nth(const struct cds_ja_type *type,
+ struct cds_ja_inode *node,
+ struct cds_ja_shadow_node *shadow_node,
+ uint8_t n)
+{
+ struct cds_ja_inode_flag **ptr;
+
+ assert(type->type_class == RCU_JA_PIGEON);
+ ptr = &((struct cds_ja_inode_flag **) node->u.data)[n];
+ if (!*ptr)
+ return -ENOENT;
+ rcu_assign_pointer(*ptr, NULL);
+ shadow_node->nr_child--;
+ return 0;
+}
+
+/*
+ * _ja_node_clear_nth: clear nth item within a node. Return an error
+ * (negative error value) if it is not found (-ENOENT).
+ */
+static
+int _ja_node_clear_nth(const struct cds_ja_type *type,
+ struct cds_ja_inode *node,
+ struct cds_ja_shadow_node *shadow_node,
+ uint8_t n)
+{
+ switch (type->type_class) {
+ case RCU_JA_LINEAR:
+ return ja_linear_node_clear_nth(type, node, shadow_node, n);
+ case RCU_JA_POOL:
+ return ja_pool_node_clear_nth(type, node, shadow_node, n);
+ case RCU_JA_PIGEON:
+ return ja_pigeon_node_clear_nth(type, node, shadow_node, n);
+ case RCU_JA_NULL:
+ return -ENOENT;
+ default:
+ assert(0);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
/*
* ja_node_recompact_add: recompact a node, adding a new child.
* TODO: for pool type, take selection bit(s) into account.
- * Return 0 on success, -ENOENT if need to retry, or other negative
+ * Return 0 on success, -EAGAIN if need to retry, or other negative
* error value otherwise.
*/
static
-int ja_node_recompact_add(struct cds_ja *ja,
+int ja_node_recompact(enum ja_recompact mode,
+ struct cds_ja *ja,
unsigned int old_type_index,
const struct cds_ja_type *old_type,
struct cds_ja_inode *old_node,
{
unsigned int new_type_index;
struct cds_ja_inode *new_node;
+ struct cds_ja_shadow_node *new_shadow_node;
const struct cds_ja_type *new_type;
struct cds_ja_inode_flag *new_node_flag;
- int new_shadow = 0;
int ret;
+ int fallback = 0;
- if (!shadow_node) {
- new_type_index = 0;
- } else {
- new_type_index = old_type_index + 1;
+ switch (mode) {
+ case JA_RECOMPACT:
+ new_type_index = old_type_index;
+ break;
+ case JA_RECOMPACT_ADD:
+ if (!shadow_node || old_type_index == NODE_INDEX_NULL) {
+ new_type_index = 0;
+ } else {
+ new_type_index = old_type_index + 1;
+ }
+ break;
+ case JA_RECOMPACT_DEL:
+ if (old_type_index == 0) {
+ new_type_index = NODE_INDEX_NULL;
+ } else {
+ new_type_index = old_type_index - 1;
+ }
+ break;
+ default:
+ assert(0);
}
- new_type = &ja_types[new_type_index];
- new_node = alloc_cds_ja_node(new_type);
- if (!new_node)
- return -ENOMEM;
- new_node_flag = ja_node_flag(new_node, new_type_index);
- ret = rcuja_shadow_set(ja->ht, new_node, shadow_node);
- if (ret) {
- free(new_node);
- return ret;
+retry: /* for fallback */
+ dbg_printf("Recompact from type %d to type %d\n",
+ old_type_index, new_type_index);
+ new_type = &ja_types[new_type_index];
+ if (new_type_index != NODE_INDEX_NULL) {
+ new_node = alloc_cds_ja_node(new_type);
+ if (!new_node)
+ return -ENOMEM;
+ new_node_flag = ja_node_flag(new_node, new_type_index);
+ dbg_printf("Recompact inherit lock from %p\n", shadow_node);
+ new_shadow_node = rcuja_shadow_set(ja->ht, new_node, shadow_node);
+ if (!new_shadow_node) {
+ free(new_node);
+ return -ENOMEM;
+ }
+ if (fallback)
+ new_shadow_node->fallback_removal_count =
+ JA_FALLBACK_REMOVAL_COUNT;
+ } else {
+ new_node = NULL;
+ new_node_flag = NULL;
}
- if (!shadow_node) {
- shadow_node = rcuja_shadow_lookup_lock(ja->ht, new_node);
- assert(shadow_node);
- new_shadow = 1;
- }
+ assert(mode != JA_RECOMPACT_ADD || old_type->type_class != RCU_JA_PIGEON);
- /*
- * We need to clear nr_child, because it will be re-incremented
- * by _ja_node_set_nth().
- */
- shadow_node->nr_child = 0;
+ if (new_type_index == NODE_INDEX_NULL)
+ goto skip_copy;
- assert(old_type->type_class != RCU_JA_PIGEON);
switch (old_type->type_class) {
case RCU_JA_LINEAR:
{
ja_linear_node_get_ith_pos(old_type, old_node, i, &v, &iter);
if (!iter)
continue;
- ret = _ja_node_set_nth(new_type, new_node, shadow_node,
+ if (mode == JA_RECOMPACT_DEL && v == n)
+ continue;
+ ret = _ja_node_set_nth(new_type, new_node,
+ new_shadow_node,
v, iter);
+ if (new_type->type_class == RCU_JA_POOL && ret) {
+ goto fallback_toosmall;
+ }
assert(!ret);
}
break;
j, &v, &iter);
if (!iter)
continue;
- ret = _ja_node_set_nth(new_type, new_node, shadow_node,
+ if (mode == JA_RECOMPACT_DEL && v == n)
+ continue;
+ ret = _ja_node_set_nth(new_type, new_node,
+ new_shadow_node,
v, iter);
+ if (new_type->type_class == RCU_JA_POOL
+ && ret) {
+ goto fallback_toosmall;
+ }
assert(!ret);
}
}
break;
}
+ case RCU_JA_NULL:
+ assert(mode == JA_RECOMPACT_ADD);
+ break;
case RCU_JA_PIGEON:
+ {
+ uint8_t nr_child;
+ unsigned int i;
+
+ assert(mode == JA_RECOMPACT_DEL);
+ nr_child = shadow_node->nr_child;
+ for (i = 0; i < nr_child; i++) {
+ struct cds_ja_inode_flag *iter;
+
+ iter = ja_pigeon_node_get_ith_pos(old_type, old_node, i);
+ if (!iter)
+ continue;
+ if (mode == JA_RECOMPACT_DEL && i == n)
+ continue;
+ ret = _ja_node_set_nth(new_type, new_node,
+ new_shadow_node,
+ i, iter);
+ if (new_type->type_class == RCU_JA_POOL && ret) {
+ goto fallback_toosmall;
+ }
+ assert(!ret);
+ }
+ break;
+ }
default:
assert(0);
ret = -EINVAL;
- goto unlock_new_shadow;
+ goto end;
}
-
- /* add node */
- ret = _ja_node_set_nth(new_type, new_node, shadow_node,
- n, child_node_flag);
- assert(!ret);
- /* Return pointer to new recompacted new through old_node_flag */
+skip_copy:
+
+ if (JA_RECOMPACT_ADD) {
+ /* add node */
+ ret = _ja_node_set_nth(new_type, new_node,
+ new_shadow_node,
+ n, child_node_flag);
+ assert(!ret);
+ }
+ /* Return pointer to new recompacted node through old_node_flag */
*old_node_flag = new_node_flag;
- ret = rcuja_shadow_clear(ja->ht, old_node,
- RCUJA_SHADOW_CLEAR_FREE_NODE);
- assert(!ret);
+ if (old_node) {
+ int flags;
+
+ flags = RCUJA_SHADOW_CLEAR_FREE_NODE;
+ /*
+ * It is OK to free the lock associated with a node
+ * going to NULL, since we are holding the parent lock.
+ * This synchronizes removal with re-add of that node.
+ */
+ if (new_type_index == NODE_INDEX_NULL)
+ flags = RCUJA_SHADOW_CLEAR_FREE_LOCK;
+ ret = rcuja_shadow_clear(ja->ht, old_node, shadow_node,
+ flags);
+ assert(!ret);
+ }
ret = 0;
-
-unlock_new_shadow:
- if (new_shadow)
- rcuja_shadow_unlock(shadow_node);
+end:
return ret;
+
+fallback_toosmall:
+ /* fallback if next pool is too small */
+ ret = rcuja_shadow_clear(ja->ht, new_node, new_shadow_node,
+ RCUJA_SHADOW_CLEAR_FREE_NODE);
+ assert(!ret);
+
+ /* Choose fallback type: pigeon */
+ new_type_index = (1UL << JA_TYPE_BITS) - 1;
+ dbg_printf("Fallback to type %d\n", new_type_index);
+ uatomic_inc(&ja->nr_fallback);
+ fallback = 1;
+ goto retry;
}
/*
- * Return 0 on success, -ENOENT if need to retry, or other negative
+ * Return 0 on success, -EAGAIN if need to retry, or other negative
* error value otherwise.
*/
static
const struct cds_ja_type *type;
struct cds_ja_inode *node;
+ dbg_printf("ja_node_set_nth for n=%u, node %p, shadow %p\n",
+ (unsigned int) n, ja_node_ptr(*node_flag), shadow_node);
+
node = ja_node_ptr(*node_flag);
type_index = ja_node_type(*node_flag);
type = &ja_types[type_index];
ret = _ja_node_set_nth(type, node, shadow_node,
n, child_node_flag);
- if (ret == -ENOSPC) {
+ switch (ret) {
+ case -ENOSPC:
/* Not enough space in node, need to recompact. */
- ret = ja_node_recompact_add(ja, type_index, type, node,
+ ret = ja_node_recompact(JA_RECOMPACT_ADD, ja, type_index, type, node,
shadow_node, node_flag, n, child_node_flag);
+ break;
+ case -ERANGE:
+ /* Node needs to be recompacted. */
+ ret = ja_node_recompact(JA_RECOMPACT, ja, type_index, type, node,
+ shadow_node, node_flag, n, child_node_flag);
+ break;
+ }
+ return ret;
+}
+
+/*
+ * Return 0 on success, -EAGAIN if need to retry, or other negative
+ * error value otherwise.
+ */
+static
+int ja_node_clear_nth(struct cds_ja *ja,
+ struct cds_ja_inode_flag **node_flag, uint8_t n,
+ struct cds_ja_shadow_node *shadow_node)
+{
+ int ret;
+ unsigned int type_index;
+ const struct cds_ja_type *type;
+ struct cds_ja_inode *node;
+
+ dbg_printf("ja_node_clear_nth for n=%u, node %p, shadow %p\n",
+ (unsigned int) n, ja_node_ptr(*node_flag), shadow_node);
+
+ node = ja_node_ptr(*node_flag);
+ type_index = ja_node_type(*node_flag);
+ type = &ja_types[type_index];
+ ret = _ja_node_clear_nth(type, node, shadow_node, n);
+ if (ret == -EFBIG) {
+ /* Should to try recompaction. */
+ ret = ja_node_recompact(JA_RECOMPACT_DEL, ja, type_index, type, node,
+ shadow_node, node_flag, n, NULL);
}
return ret;
}
return NULL;
for (i = 1; i < tree_depth; i++) {
+ uint8_t iter_key;
+
+ iter_key = (uint8_t) (key >> (JA_BITS_PER_BYTE * (tree_depth - i - 1)));
node_flag = ja_node_get_nth(node_flag, NULL,
- (unsigned char) key);
+ iter_key);
+ dbg_printf("cds_ja_lookup iter key lookup %u finds node_flag %p\n",
+ (unsigned int) iter_key, node_flag);
if (!ja_node_ptr(node_flag))
return NULL;
- key >>= JA_BITS_PER_BYTE;
}
/* Last level lookup succeded. We got an actual match. */
struct cds_ja_inode_flag *node_flag,
struct cds_ja_inode_flag *parent_node_flag,
uint64_t key,
- unsigned int depth,
+ unsigned int level,
struct cds_ja_node *child_node)
{
struct cds_ja_shadow_node *shadow_node = NULL,
- *parent_shadow_node = NULL;
+ *parent_shadow_node = NULL,
+ *iter_shadow_node;
struct cds_ja_inode *node = ja_node_ptr(node_flag);
struct cds_ja_inode *parent_node = ja_node_ptr(parent_node_flag);
struct cds_hlist_head head;
struct cds_ja_inode_flag *iter_node_flag, *iter_dest_node_flag;
int ret, i;
- struct cds_ja_inode_flag *created_nodes[JA_MAX_INTERNAL_DEPTH];
+ struct cds_ja_inode_flag *created_nodes[JA_MAX_DEPTH];
int nr_created_nodes = 0;
+ dbg_printf("Attach node at level %u (node %p, node_flag %p)\n",
+ level, node, node_flag);
+
assert(node);
shadow_node = rcuja_shadow_lookup_lock(ja->ht, node);
if (!shadow_node) {
- ret = -ENOENT;
+ ret = -EAGAIN;
goto end;
}
if (parent_node) {
parent_shadow_node = rcuja_shadow_lookup_lock(ja->ht,
parent_node);
if (!parent_shadow_node) {
- ret = -ENOENT;
+ ret = -EAGAIN;
goto unlock_shadow;
}
}
+ /* Create new branch, starting from bottom */
CDS_INIT_HLIST_HEAD(&head);
cds_hlist_add_head_rcu(&child_node->list, &head);
+ iter_node_flag = (struct cds_ja_inode_flag *) head.next;
+
+ /* Create shadow node for the leaf node */
+ dbg_printf("leaf shadow node creation\n");
+ iter_shadow_node = rcuja_shadow_set(ja->ht,
+ ja_node_ptr(iter_node_flag), NULL);
+ if (!iter_shadow_node) {
+ ret = -ENOMEM;
+ goto check_error;
+ }
+ created_nodes[nr_created_nodes++] = iter_node_flag;
- iter_dest_node_flag = NULL;
- ret = ja_node_set_nth(ja, &iter_dest_node_flag,
- key >> (JA_BITS_PER_BYTE * (ja->tree_depth - 2)),
- (struct cds_ja_inode_flag *) head.next,
- NULL);
- if (ret)
- goto unlock_parent;
- created_nodes[nr_created_nodes++] = iter_dest_node_flag;
- iter_node_flag = iter_dest_node_flag;
+ for (i = ja->tree_depth; i > (int) level; i--) {
+ uint8_t iter_key;
- /* Create new branch, starting from bottom */
- for (i = ja->tree_depth - 2; i >= (int) depth; i--) {
+ iter_key = (uint8_t) (key >> (JA_BITS_PER_BYTE * (ja->tree_depth - i)));
+ dbg_printf("branch creation level %d, key %u\n",
+ i - 1, (unsigned int) iter_key);
iter_dest_node_flag = NULL;
ret = ja_node_set_nth(ja, &iter_dest_node_flag,
- key >> (JA_BITS_PER_BYTE * (i - 1)),
+ iter_key,
iter_node_flag,
NULL);
if (ret)
iter_node_flag = iter_dest_node_flag;
}
+ if (level > 1) {
+ uint8_t iter_key;
+
+ iter_key = (uint8_t) (key >> (JA_BITS_PER_BYTE * (ja->tree_depth - level)));
+ /* We need to use set_nth on the previous level. */
+ iter_dest_node_flag = node_flag;
+ ret = ja_node_set_nth(ja, &iter_dest_node_flag,
+ iter_key,
+ iter_node_flag,
+ shadow_node);
+ if (ret)
+ goto check_error;
+ created_nodes[nr_created_nodes++] = iter_dest_node_flag;
+ iter_node_flag = iter_dest_node_flag;
+ }
+
/* Publish new branch */
+ dbg_printf("Publish branch %p, replacing %p\n",
+ iter_node_flag, *node_flag_ptr);
rcu_assign_pointer(*node_flag_ptr, iter_node_flag);
/* Success */
if (ret) {
for (i = 0; i < nr_created_nodes; i++) {
int tmpret;
+ int flags;
+
+ flags = RCUJA_SHADOW_CLEAR_FREE_LOCK;
+ if (i)
+ flags |= RCUJA_SHADOW_CLEAR_FREE_NODE;
tmpret = rcuja_shadow_clear(ja->ht,
ja_node_ptr(created_nodes[i]),
- RCUJA_SHADOW_CLEAR_FREE_NODE
- | RCUJA_SHADOW_CLEAR_FREE_LOCK);
+ NULL,
+ flags);
assert(!tmpret);
}
}
-unlock_parent:
if (parent_shadow_node)
rcuja_shadow_unlock(parent_shadow_node);
unlock_shadow:
shadow_node = rcuja_shadow_lookup_lock(ja->ht,
(struct cds_ja_inode *) head);
if (!shadow_node)
- return -ENOENT;
+ return -EAGAIN;
cds_hlist_add_head_rcu(&node->list, head);
rcuja_shadow_unlock(shadow_node);
return 0;
struct cds_ja_node *new_node)
{
unsigned int tree_depth, i;
- uint64_t iter_key;
struct cds_ja_inode_flag **node_flag_ptr; /* in parent */
struct cds_ja_inode_flag *node_flag,
*parent_node_flag,
tree_depth = ja->tree_depth;
retry:
- iter_key = key;
+ dbg_printf("cds_ja_add attempt: key %" PRIu64 ", node %p\n",
+ key, new_node);
parent2_node_flag = NULL;
- parent_node_flag = NULL;
+ parent_node_flag =
+ (struct cds_ja_inode_flag *) &ja->root; /* Use root ptr address as key for mutex */
node_flag_ptr = &ja->root;
node_flag = rcu_dereference(*node_flag_ptr);
/* Iterate on all internal levels */
- for (i = 0; i < tree_depth - 1; i++) {
+ for (i = 1; i < tree_depth; i++) {
+ uint8_t iter_key;
+
+ dbg_printf("cds_ja_add iter node_flag_ptr %p node_flag %p\n",
+ *node_flag_ptr, node_flag);
if (!ja_node_ptr(node_flag)) {
ret = ja_attach_node(ja, node_flag_ptr,
parent_node_flag, parent2_node_flag,
key, i, new_node);
- if (ret == -ENOENT || ret == -EEXIST)
+ if (ret == -EAGAIN || ret == -EEXIST)
goto retry;
else
goto end;
}
+ iter_key = (uint8_t) (key >> (JA_BITS_PER_BYTE * (tree_depth - i - 1)));
parent2_node_flag = parent_node_flag;
parent_node_flag = node_flag;
node_flag = ja_node_get_nth(node_flag,
&node_flag_ptr,
- (unsigned char) iter_key);
- iter_key >>= JA_BITS_PER_BYTE;
+ iter_key);
+ dbg_printf("cds_ja_add iter key lookup %u finds node_flag %p node_flag_ptr %p\n",
+ (unsigned int) iter_key, node_flag, *node_flag_ptr);
}
/*
* level, or chain it if key is already present.
*/
if (!ja_node_ptr(node_flag)) {
+ dbg_printf("cds_ja_add last node_flag_ptr %p node_flag %p\n",
+ *node_flag_ptr, node_flag);
ret = ja_attach_node(ja, node_flag_ptr, parent_node_flag,
parent2_node_flag, key, i, new_node);
} else {
(struct cds_hlist_head *) ja_node_ptr(node_flag),
new_node);
}
- if (ret == -ENOENT)
+ if (ret == -EAGAIN)
goto retry;
end:
return ret;
const struct rcu_flavor_struct *flavor)
{
struct cds_ja *ja;
+ int ret;
+ struct cds_ja_shadow_node *root_shadow_node;
ja = calloc(sizeof(*ja), 1);
if (!ja)
/* ja->root is NULL */
/* tree_depth 0 is for pointer to root node */
- ja->tree_depth = (key_bits >> JA_BITS_PER_BYTE) + 1;
- assert(ja->tree_depth <= JA_MAX_INTERNAL_DEPTH + 1);
+ ja->tree_depth = (key_bits >> JA_LOG2_BITS_PER_BYTE) + 1;
+ assert(ja->tree_depth <= JA_MAX_DEPTH);
ja->ht = rcuja_create_ht(flavor);
if (!ja->ht)
goto ht_error;
+
+ /*
+ * Note: we should not free this node until judy array destroy.
+ */
+ root_shadow_node = rcuja_shadow_set(ja->ht,
+ ja_node_ptr((struct cds_ja_inode_flag *) &ja->root),
+ NULL);
+ if (!root_shadow_node) {
+ ret = -ENOMEM;
+ goto ht_node_error;
+ }
+ root_shadow_node->is_root = 1;
+
return ja;
+ht_node_error:
+ ret = rcuja_delete_ht(ja->ht);
+ assert(!ret);
ht_error:
check_error:
free(ja);
ret = rcuja_delete_ht(ja->ht);
if (ret)
return ret;
+ if (uatomic_read(&ja->nr_fallback))
+ fprintf(stderr,
+ "[warning] RCU Judy Array used %lu fallback node(s)\n",
+ uatomic_read(&ja->nr_fallback));
free(ja);
return 0;
}