{
struct mask_array *new;
+ size = max(MASK_ARRAY_SIZE_MIN, size);
new = kzalloc(sizeof(struct mask_array) +
sizeof(struct sw_flow_mask *) * size, GFP_KERNEL);
if (!new)
old = ovsl_dereference(tbl->mask_array);
if (old) {
- int i;
+ int i, count = 0;
- for (i = 0; i < min(old->max, new->max); i++)
- new->masks[i] = old->masks[i];
+ for (i = 0; i < old->max; i++) {
+ if (ovsl_dereference(old->masks[i]))
+ new->masks[count++] = old->masks[i];
+ }
- BUG_ON(old->count > new->max);
- new->count = old->count;
+ new->count = count;
}
rcu_assign_pointer(tbl->mask_array, new);
return 0;
}
-static void tbl_mask_array_delete_mask(struct mask_array *ma,
- const struct sw_flow_mask *mask)
-{
- int i = 0;
-
- /* Delete a mask pointer from the valid section.
- *
- * Also move the last entry in its place, so there is no
- * whole in the valid section.
- *
- * Notice the last entry still points to the original mask.
- *
- * <Note>: there is a small race window that may cause a mask
- * to be missed in a search. Imaging a core is
- * walking through the array, passing the index of deleting mask.
- * But before reaching the last entry, it is overwritten,
- * by another core that is adding a new mask, now the last entry
- * will point to the new mask. In this case, the moved up last
- * entry can be missed by the core walking the mask array.
- *
- * In case this missed mask would have led to successful
- * lookup, Hitting the race window could cause a packet to miss
- * kernel flow cache, and be sent to the user space.
- * </Note>
- */
- for (i = 0; i < ma->count; i++)
- if (mask == ovsl_dereference(ma->masks[i])) {
- struct sw_flow_mask *last;
-
- last = ovsl_dereference(ma->masks[ma->count - 1]);
- rcu_assign_pointer(ma->masks[i], last);
- ma->count--;
- break;
- }
-
- /* Remove the deleted mask pointers from the invalid section. */
- for (i = ma->count; i < ma->max; i++)
- if (mask == ovsl_dereference(ma->masks[i]))
- RCU_INIT_POINTER(ma->masks[i], NULL);
-}
-
int ovs_flow_tbl_init(struct flow_table *table)
{
struct table_instance *ti;
return 0;
free_mask_array:
- kfree((struct mask_array __force *)table->mask_array);
+ kfree(ma);
free_mask_cache:
free_percpu(table->mask_cache);
return -ENOMEM;
mask = rcu_dereference_ovsl(ma->masks[i]);
if (!mask)
- return NULL;
+ continue;
flow = masked_flow_lookup(ti, key, mask, n_mask_hit);
if (flow) { /* Found */
int i;
/* Always called under ovs-mutex. */
- for (i = 0; i < ma->count; i++) {
+ for (i = 0; i < ma->max; i++) {
struct table_instance *ti = ovsl_dereference(tbl->ti);
u32 __always_unused n_mask_hit;
struct sw_flow_mask *mask;
struct sw_flow *flow;
mask = ovsl_dereference(ma->masks[i]);
+ if (!mask)
+ continue;
flow = masked_flow_lookup(ti, match->key, mask, &n_mask_hit);
if (flow && ovs_flow_cmp_unmasked_key(flow, match))
return flow;
return table_instance_rehash(ti, ti->n_buckets * 2);
}
+static void tbl_mask_array_delete_mask(struct mask_array *ma,
+ struct sw_flow_mask *mask)
+{
+ int i;
+
+ /* Remove the deleted mask pointers from the array */
+ for (i = 0; i < ma->max; i++) {
+ if (mask == ovsl_dereference(ma->masks[i])) {
+ RCU_INIT_POINTER(ma->masks[i], NULL);
+ ma->count--;
+ call_rcu(&mask->rcu, rcu_free_sw_flow_mask_cb);
+ return;
+ }
+ }
+ BUG();
+}
+
/* Remove 'mask' from the mask list, if it is not needed any more. */
static void flow_mask_remove(struct flow_table *tbl, struct sw_flow_mask *mask)
{
struct mask_array *ma;
ma = ovsl_dereference(tbl->mask_array);
- /* Shrink the mask array if necessary. */
- if (ma->max > MASK_ARRAY_SIZE_MIN * 2
- && ma->count <= ma->max / 4) {
+ tbl_mask_array_delete_mask(ma, mask);
+ /* Shrink the mask array if necessary. */
+ if (ma->max >= (MASK_ARRAY_SIZE_MIN * 2) &&
+ ma->count <= (ma->max / 3))
tbl_mask_array_realloc(tbl, ma->max / 2);
- ma = ovsl_dereference(tbl->mask_array);
- }
- tbl_mask_array_delete_mask(ma, mask);
- call_rcu(&mask->rcu, rcu_free_sw_flow_mask_cb);
}
}
}
int i;
ma = ovsl_dereference(tbl->mask_array);
- for (i = 0; i < ma->count; i++) {
+ for (i = 0; i < ma->max; i++) {
struct sw_flow_mask *t;
t = ovsl_dereference(ma->masks[i]);
mask = flow_mask_find(tbl, new);
if (!mask) {
struct mask_array *ma;
+ int i;
/* Allocate a new mask if none exsits. */
mask = mask_alloc();
int err;
err = tbl_mask_array_realloc(tbl, ma->max +
- MASK_ARRAY_SIZE_MIN);
+ MASK_ARRAY_SIZE_MIN);
if (err) {
kfree(mask);
return err;
ma = ovsl_dereference(tbl->mask_array);
}
- rcu_assign_pointer(ma->masks[ma->count], mask);
- ma->count++;
+ for (i = 0; i < ma->max; i++) {
+ struct sw_flow_mask *t;
+
+ t = ovsl_dereference(ma->masks[i]);
+ if (!t) {
+ rcu_assign_pointer(ma->masks[i], mask);
+ ma->count++;
+ break;
+ }
+ }
+
} else {
BUG_ON(!mask->ref_count);
mask->ref_count++;
projects / cascardo / ovs.git / blobdiff