/* 32-bit: 101 to 256 children, 1024 bytes */
/* 64-bit: 113 to 256 children, 2048 bytes */
/* Leaf nodes are implicit from their height in the tree */
+ RCU_JA_NR_TYPES,
};
struct rcu_ja_type {
#if (CAA_BITS_PER_LONG < 64)
/* 32-bit pointers */
+enum {
+ ja_type_0_max_child = 1,
+ ja_type_1_max_child = 3,
+ ja_type_2_max_child = 6,
+ ja_type_3_max_child = 12,
+ ja_type_4_max_child = 25,
+ ja_type_5_max_child = 48,
+ ja_type_6_max_child = 92,
+ ja_type_7_max_child = 256,
+};
+
+enum {
+ ja_type_5_nr_pool_order = 1,
+ ja_type_6_nr_pool_order = 2,
+};
+
const struct rcu_ja_type ja_types[] = {
- { .type_class = RCU_JA_LINEAR, .min_child = 1, .max_child = 1, .order = 3, },
- { .type_class = RCU_JA_LINEAR, .min_child = 1, .max_child = 3, .order = 4, },
- { .type_class = RCU_JA_LINEAR, .min_child = 3, .max_child = 6, .order = 5, },
- { .type_class = RCU_JA_LINEAR, .min_child = 4, .max_child = 12, .order = 6, },
- { .type_class = RCU_JA_LINEAR, .min_child = 10, .max_child = 25, .order = 7, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 1, .max_child = ja_type_0_max_child, .order = 3, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 1, .max_child = ja_type_1_max_child, .order = 4, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 3, .max_child = ja_type_2_max_child, .order = 5, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 4, .max_child = ja_type_3_max_child, .order = 6, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 10, .max_child = ja_type_4_max_child, .order = 7, },
/* Pools may fill sooner than max_child */
- { .type_class = RCU_JA_POOL, .min_child = 20, .max_child = 48, .order = 8, .nr_pool_order = 1, .pool_size_order = 7, },
- { .type_class = RCU_JA_POOL, .min_child = 45, .max_child = 92, .order = 9, .nr_pool_order = 2, .pool_size_order = 7, },
+ { .type_class = RCU_JA_POOL, .min_child = 20, .max_child = ja_type_5_max_child, .order = 8, .nr_pool_order = ja_type_5_nr_pool_order, .pool_size_order = 7, },
+ { .type_class = RCU_JA_POOL, .min_child = 45, .max_child = ja_type_6_max_child, .order = 9, .nr_pool_order = ja_type_6_nr_pool_order, .pool_size_order = 7, },
/*
* TODO: Upon node removal below min_child, if child pool is
* filled beyond capacity, we need to roll back to pigeon.
*/
- { .type_class = RCU_JA_PIGEON, .min_child = 89, .max_child = 256, .order = 10, },
+ { .type_class = RCU_JA_PIGEON, .min_child = 89, .max_child = ja_type_7_max_child, .order = 10, },
};
-CAA_BUILD_BUG_ON(CAA_ARRAY_SIZE(ja_types) > JA_TYPE_MAX_NR);
#else /* !(CAA_BITS_PER_LONG < 64) */
/* 64-bit pointers */
+enum {
+ ja_type_0_max_child = 1,
+ ja_type_1_max_child = 3,
+ ja_type_2_max_child = 7,
+ ja_type_3_max_child = 14,
+ ja_type_4_max_child = 28,
+ ja_type_5_max_child = 54,
+ ja_type_6_max_child = 104,
+ ja_type_7_max_child = 256,
+};
+
+enum {
+ ja_type_5_nr_pool_order = 1,
+ ja_type_6_nr_pool_order = 2,
+};
+
const struct rcu_ja_type ja_types[] = {
- { .type_class = RCU_JA_LINEAR, .min_child = 1, .max_child = 1, .order = 4, },
- { .type_class = RCU_JA_LINEAR, .min_child = 1, .max_child = 3, .order = 5, },
- { .type_class = RCU_JA_LINEAR, .min_child = 3, .max_child = 7, .order = 6, },
- { .type_class = RCU_JA_LINEAR, .min_child = 5, .max_child = 14, .order = 7, },
- { .type_class = RCU_JA_LINEAR, .min_child = 10, .max_child = 28, .order = 8, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 1, .max_child = ja_type_0_max_child, .order = 4, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 1, .max_child = ja_type_1_max_child, .order = 5, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 3, .max_child = ja_type_2_max_child, .order = 6, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 5, .max_child = ja_type_3_max_child, .order = 7, },
+ { .type_class = RCU_JA_LINEAR, .min_child = 10, .max_child = ja_type_4_max_child, .order = 8, },
/* Pools may fill sooner than max_child. */
- { .type_class = RCU_JA_POOL, .min_child = 22, .max_child = 54, .order = 9, .nr_pool_order = 1, .pool_size_order = 8, },
- { .type_class = RCU_JA_POOL, .min_child = 51, .max_child = 104, .order = 10, .nr_pool_order = 2, .pool_size_order = 8, },
+ { .type_class = RCU_JA_POOL, .min_child = 22, .max_child = ja_type_5_max_child, .order = 9, .nr_pool_order = ja_type_5_nr_pool_order, .pool_size_order = 8, },
+ { .type_class = RCU_JA_POOL, .min_child = 51, .max_child = ja_type_6_max_child, .order = 10, .nr_pool_order = ja_type_6_nr_pool_order, .pool_size_order = 8, },
/*
* TODO: Upon node removal below min_child, if child pool is
* filled beyond capacity, we need to roll back to pigeon.
*/
- { .type_class = RCU_JA_PIGEON, .min_child = 101, .max_child = 256, .order = 11, },
+ { .type_class = RCU_JA_PIGEON, .min_child = 101, .max_child = ja_type_7_max_child, .order = 11, },
};
-CAA_BUILD_BUG_ON(CAA_ARRAY_SIZE(ja_types) > JA_TYPE_MAX_NR);
#endif /* !(BITS_PER_LONG < 64) */
+static inline __attribute__((unused))
+void static_array_size_check(void)
+{
+ CAA_BUILD_BUG_ON(CAA_ARRAY_SIZE(ja_types) > JA_TYPE_MAX_NR);
+}
+
+/* Never declared. Opaque type used to store flagged node pointers. */
+struct rcu_ja_node_flag;
+
/*
- * The rcu_ja_node starts with a byte counting the number of children in
- * the node. Then, the node-specific data is placed.
- * TODO: where should we put the mutex for the node ?
- * -> mutex could be a 0-value node count.
- * TODO: where do we keep nr children for pigeon ?
+ * The rcu_ja_node contains the compressed node data needed for
+ * read-side. For linear and pool node configurations, it starts with a
+ * byte counting the number of children in the node. Then, the
+ * node-specific data is placed.
+ * The node mutex, if any is needed, protecting concurrent updated of
+ * each node is placed in a separate hash table indexed by node address.
+ * For the pigeon configuration, the number of children is also kept in
+ * a separate hash table, indexed by node address, because it is only
+ * required for updates.
*/
+
+#define DECLARE_LINEAR_NODE(index) \
+ struct { \
+ uint8_t nr_child; \
+ uint8_t child_value[ja_type_## index ##_max_child]; \
+ struct rcu_ja_node_flag *child_ptr[ja_type_## index ##_max_child]; \
+ }
+
+#define DECLARE_POOL_NODE(index) \
+ struct { \
+ struct { \
+ uint8_t nr_child; \
+ uint8_t child_value[ja_type_## index ##_max_child >> ja_type_## index ##_nr_pool_order]; \
+ struct rcu_ja_node_flag *child_ptr[ja_type_## index ##_max_child >> ja_type_## index ##_nr_pool_order]; \
+ } linear[1U << ja_type_## index ##_nr_pool_order]; \
+ }
+
struct rcu_ja_node {
- char data[];
+ union {
+ /* Linear configuration */
+ DECLARE_LINEAR_NODE(0) conf_0;
+ DECLARE_LINEAR_NODE(1) conf_1;
+ DECLARE_LINEAR_NODE(2) conf_2;
+ DECLARE_LINEAR_NODE(3) conf_3;
+ DECLARE_LINEAR_NODE(4) conf_4;
+
+ /* Pool configuration */
+ DECLARE_POOL_NODE(5) conf_5;
+ DECLARE_POOL_NODE(6) conf_6;
+
+ /* Pigeon configuration */
+ struct {
+ struct rcu_ja_node_flag *child[ja_type_7_max_child];
+ } conf_7;
+ /* data aliasing nodes for computed accesses */
+ uint8_t data[sizeof(struct rcu_ja_node_flag *) * ja_type_7_max_child];
+ } u;
};
-/* Never declared. Opaque type used to store flagged node pointers. */
-struct rcu_ja_node_flag;
-
static
struct rcu_ja_node_flag *ja_node_flag(struct rcu_ja_node *node, unsigned int type)
{
- assert(type < JA_TYPE_NR);
+ assert(type < RCU_JA_NR_TYPES);
return (struct rcu_ja_node_flag *) (((unsigned long) node) | type);
}
unsigned int type;
type = (unsigned int) ((unsigned long) node & JA_TYPE_MASK);
- assert(type < JA_TYPE_NR);
+ assert(type < RCU_JA_NR_TYPES);
return type;
}
struct rcu_ja_node *alloc_rcu_ja_node(struct rcu_ja_type *ja_type)
{
- return zmalloc(1 << ja_type->node_order);
+ return calloc(1U << ja_type->order, sizeof(char));
}
void free_rcu_ja_node(struct rcu_ja_node *node)
#define JA_FLOOR(v, align) __JA_FLOOR_MASK(v, (typeof(v)) (align) - 1)
static
-char *align_ptr_size(char *ptr)
+uint8_t *align_ptr_size(uint8_t *ptr)
{
- return JA_ALIGN(ptr, sizeof(ptr));
+ return (uint8_t *) JA_ALIGN((unsigned long) ptr, sizeof(void *));
}
static
{
uint8_t nr_child;
uint8_t *values;
- struct rcu_ja_node_flag *pointers;
+ struct rcu_ja_node_flag **pointers;
struct rcu_ja_node_flag *ptr;
unsigned int i;
assert(!type || type->type_class == RCU_JA_LINEAR);
- nr_child = node->data[0];
+ nr_child = node->u.data[0];
cmm_smp_rmb(); /* read nr_child before values */
assert(!type || nr_child <= type->max_child);
assert(!type || nr_child >= type->min_child);
- values = &node[1];
+ values = &node->u.data[1];
for (i = 0; i < nr_child; i++) {
if (values[i] == n)
break;
if (i >= nr_child)
return NULL;
cmm_smp_rmb(); /* read values before pointer */
- pointers = align_ptr_size(&values[nr_child]);
+ pointers = (struct rcu_ja_node_flag **) align_ptr_size(&values[nr_child]);
ptr = pointers[i];
assert(ja_node_ptr(ptr) != NULL);
return ptr;
struct rcu_ja_node *node,
uint8_t n)
{
- struct rcu_ja_node_flag *ptr;
struct rcu_ja_node *linear;
assert(type->type_class == RCU_JA_POOL);
linear = (struct rcu_ja_node *)
- &node->data[((unsigned long) n >> (CHAR_BIT - type->nr_pool_order)) << type->pool_size_order];
+ &node->u.data[((unsigned long) n >> (CHAR_BIT - type->nr_pool_order)) << type->pool_size_order];
return ja_linear_node_get_nth(NULL, linear, n);
}
uint8_t n)
{
assert(type->type_class == RCU_JA_PIGEON);
- return ((struct rcu_ja_node_flag *) node->data)[n];
+ return ((struct rcu_ja_node_flag **) node->u.data)[n];
}
/* ja_node_get_nth: get nth item from a node */
projects / userspace-rcu.git / commitdiff
