I have a high level question:
Since mask can be moved around in the array without causing problem,
when deleting a mask, why not simply move the highest
element over?
On Mon, Apr 7, 2014 at 3:00 PM, Pravin <pshe...@nicira.com> wrote:
> From: Pravin Shelar <pshe...@nicira.com>
>
> Along with flow-table rehashing OVS can compact masks array. This
> allows us to calculate highest index for mask array.
>
> Signed-off-by: Pravin B Shelar <pshe...@nicira.com>
> ---
> datapath/flow_table.c | 24 ++++++++++++++++++++----
> datapath/flow_table.h | 2 +-
> 2 files changed, 21 insertions(+), 5 deletions(-)
>
> diff --git a/datapath/flow_table.c b/datapath/flow_table.c
> index 5665cfc..b2c0497 100644
> --- a/datapath/flow_table.c
> +++ b/datapath/flow_table.c
> @@ -230,6 +230,7 @@ static struct mask_array *tbl_mask_array_alloc(int size)
>
> new->count = 0;
> new->max = size;
> + new->hi_index = 0;
>
> return new;
> }
> @@ -252,6 +253,8 @@ static int tbl_mask_array_realloc(struct flow_table *tbl,
> int size)
> new->masks[new->count++] = old->masks[i];
> }
> }
> +
> + new->hi_index = new->count;
> rcu_assign_pointer(tbl->mask_array, new);
>
> if (old)
> @@ -260,6 +263,17 @@ static int tbl_mask_array_realloc(struct flow_table
> *tbl, int size)
> return 0;
> }
>
> +static void tbl_mask_array_compact(struct flow_table *tbl)
> +{
> + struct mask_array *ma;
> + int size;
> +
> + ma = ovsl_dereference(tbl->mask_array);
> +
> + size = roundup(ma->count, MASK_ARRAY_SIZE_MIN);
> + tbl_mask_array_realloc(tbl, size);
> +}
> +
> int ovs_flow_tbl_init(struct flow_table *table)
> {
> struct table_instance *ti;
> @@ -521,7 +535,7 @@ static struct sw_flow *flow_lookup(struct flow_table *tbl,
> int i, c;
>
> c = 0;
> - for (i = 0; i < ma->max; i++) {
> + for (i = 0; i < ma->hi_index; i++) {
> struct sw_flow_mask *mask;
>
> mask = rcu_dereference_ovsl(ma->masks[i]);
> @@ -631,7 +645,7 @@ static void flow_mask_remove(struct flow_table *tbl,
> struct sw_flow_mask *mask)
> int i;
>
> ma = ovsl_dereference(tbl->mask_array);
> - for (i = 0; i < ma->max; i++) {
> + for (i = 0; i < ma->hi_index; i++) {
> if (mask == ovsl_dereference(ma->masks[i])) {
> RCU_INIT_POINTER(ma->masks[i], NULL);
> ma->count--;
> @@ -688,7 +702,7 @@ static struct sw_flow_mask *flow_mask_find(const struct
> flow_table *tbl,
> int i;
>
> ma = ovsl_dereference(tbl->mask_array);
> - for (i = 0; i < ma->max; i++) {
> + for (i = 0; i < ma->hi_index; i++) {
> struct sw_flow_mask *t;
>
> t = ovsl_dereference(ma->masks[i]);
> @@ -736,8 +750,9 @@ static int flow_mask_insert(struct flow_table *tbl,
> struct sw_flow *flow,
>
> t = ovsl_dereference(ma->masks[i]);
> if (!t) {
> - rcu_assign_pointer(ma->masks[i], mask);
> ma->count++;
> + ma->hi_index = i + 1;
> + rcu_assign_pointer(ma->masks[i], mask);
> break;
> }
> }
> @@ -777,6 +792,7 @@ int ovs_flow_tbl_insert(struct flow_table *table, struct
> sw_flow *flow,
> if (new_ti) {
> rcu_assign_pointer(table->ti, new_ti);
> table_instance_destroy(ti, true);
> + tbl_mask_array_compact(table);
> table->last_rehash = jiffies;
> }
> return 0;
> diff --git a/datapath/flow_table.h b/datapath/flow_table.h
> index ee86953..cf898ba 100644
> --- a/datapath/flow_table.h
> +++ b/datapath/flow_table.h
> @@ -43,7 +43,7 @@ struct mask_cache_entry {
>
> struct mask_array {
> struct rcu_head rcu;
> - int count, max;
> + int count, max, hi_index;
> struct sw_flow_mask __rcu *masks[];
> };
>
> --
> 1.7.9.5
>
> _______________________________________________
> dev mailing list
> dev@openvswitch.org
> http://openvswitch.org/mailman/listinfo/dev
_______________________________________________
dev mailing list
dev@openvswitch.org
http://openvswitch.org/mailman/listinfo/dev
