ofproto: Store meters using hmap

Currently, meters are stored in a fixed pointer array. It is not
very efficient since the controller, at least in theory, can
pick any meter id (up to the limits to uint32_t), not necessarily
within the lower end of a region, or in close range to each other.
In particular, OFPM_SLOWPATH and OFPM_CONTROLLER meters are specified
at the high region.

Switching to using hmap. Ofproto layer does not restrict
the number of meters that controller can add, nor does it care
about the value of meter_id. Datapth limits the number of meters
ofproto layer can support at run time.

Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Jarno Rajahalme <jarno@ovn.org>

1 files changed, 2 insertions, 5 deletions

diff --git a/ofproto/ofproto-provider.h b/ofproto/ofproto-provider.h
index b7b12cdfd..000326d7f 100644
--- a/ofproto/ofproto-provider.h
+++ b/ofproto/ofproto-provider.h
@@ -109,12 +109,9 @@ struct ofproto {
     /* List of expirable flows, in all flow tables. */
     struct ovs_list expirable OVS_GUARDED_BY(ofproto_mutex);
 
-    /* Meter table.
-     * OpenFlow meters start at 1.  To avoid confusion we leave the first
-     * pointer in the array un-used, and index directly with the OpenFlow
-     * meter_id. */
+    /* Meter table.  */
     struct ofputil_meter_features meter_features;
-    struct meter **meters; /* 'meter_features.max_meter' + 1 pointers. */
+    struct hmap meters;             /* uint32_t indexed 'struct meter *'.  */
 
     /* OpenFlow connections. */
     struct connmgr *connmgr;