Reinterpret base for meter band types bitmap.

OpenFlow 1.3 says that the band_types member of struct ofp_meter_features
is a bitmap of OFPMBT_* values.  The OFPMBT_* values are 1-based, so
until now, to avoid wasting bit 0, OVS mapped an OFPMBT_* with value 1 to
bit 0, value 2 to bit 1, and so on.  However, according to
http://openvswitch.org/pipermail/dev/2013-July/029666.html,
other OpenFlow implementations directly translate value 1 to bit 1,
value 2 to bit 2, and so on.  This commit changes Open vSwitch to use this
more common interpretation.

A request for clarification of this issue in the OpenFlow standard has been
filed with the ONF Extensibility Working Group as issue EXT-345.

Reported-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>

diff --git a/lib/ofp-print.c b/lib/ofp-print.c
index 21989a9..02d4380 100644 (file)
--- a/lib/ofp-print.c
+++ b/lib/ofp-print.c
@@ -1106,13 +1106,9 @@ ofputil_meter_capabilities_to_name(uint32_t bit)
 static const char *
 ofputil_meter_band_types_to_name(uint32_t bit)
 {
-    /*
-     * Note: Meter band types start from 1.  We assume that the lowest bit
-     * in the band_types corresponds to DROP band type (1).
-     */
     switch (bit) {
-    case 1 << (OFPMBT13_DROP - 1):          return "drop";
-    case 1 << (OFPMBT13_DSCP_REMARK - 1):   return "dscp_remark";
+    case 1 << OFPMBT13_DROP:          return "drop";
+    case 1 << OFPMBT13_DSCP_REMARK:   return "dscp_remark";
     }
 
     return NULL;

diff --git a/tests/ofp-print.at b/tests/ofp-print.at
index 986b931..266af6c 100644 (file)
--- a/tests/ofp-print.at
+++ b/tests/ofp-print.at
@@ -1670,7 +1670,7 @@ AT_SETUP([OFPST_METER_FEATURES reply - OF1.3])
 AT_KEYWORDS([ofp-print OFPT_STATS_REPLY])
 AT_CHECK([ovs-ofctl ofp-print "\
 04 13 00 20 00 00 00 02 00 0b 00 00 00 00 00 00 \
-00 01 00 00 00 00 00 03 00 00 00 0F 10 02 00 00 \
+00 01 00 00 00 00 00 06 00 00 00 0F 10 02 00 00 \
 "], [0], [dnl
 OFPST_METER_FEATURES reply (OF1.3) (xid=0x2):
 max_meter:65536 max_bands:16 max_color:2