If the datapath actions exceed the maximum size of a Netlink attribute
(about 64 kB), then previously we would assert-fail (before commit
542024c4c3d36 "ofproto-dpif-xlate: Suppress oversize datapath actions.")
or just drop all of them (after that commit). This commit makes OVS cope
by slow-pathing the flow and executing all of its actions in userspace.
Signed-off-by: Ben Pfaff <b...@nicira.com>
---
lib/dpif.c | 4 +++-
ofproto/ofproto-dpif-xlate.c | 11 ++++++-----
2 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/lib/dpif.c b/lib/dpif.c
index b284e13..ed84f5f 100644
--- a/lib/dpif.c
+++ b/lib/dpif.c
@@ -1183,6 +1183,8 @@ dpif_execute__(struct dpif *dpif, const struct
dpif_execute *execute)
* OVS_ACTION_ATTR_USERSPACE actions it passes the packet through to the dpif
* implementation.
*
+ * This works even if 'actions_len' is too long for a Netlink attribute.
+ *
* Returns 0 if successful, otherwise a positive errno value. */
int
dpif_execute(struct dpif *dpif,
@@ -1198,7 +1200,7 @@ dpif_execute(struct dpif *dpif,
execute.actions = actions;
execute.actions_len = actions_len;
execute.packet = buf;
- execute.needs_help = needs_help;
+ execute.needs_help = needs_help || nl_attr_oversized(actions_len);
return dpif_execute__(dpif, &execute);
}
diff --git a/ofproto/ofproto-dpif-xlate.c b/ofproto/ofproto-dpif-xlate.c
index 4fb0d5e..ec83db7 100644
--- a/ofproto/ofproto-dpif-xlate.c
+++ b/ofproto/ofproto-dpif-xlate.c
@@ -49,6 +49,7 @@
#include "vlog.h"
COVERAGE_DEFINE(xlate_actions);
+COVERAGE_DEFINE(xlate_actions_oversize);
VLOG_DEFINE_THIS_MODULE(ofproto_dpif_xlate);
@@ -2832,11 +2833,11 @@ xlate_actions__(struct xlate_in *xin, struct xlate_out
*xout)
if (nl_attr_oversized(ctx.xout->odp_actions.size)) {
/* These datapath actions are too big for a Netlink attribute, so we
- * can't execute them. */
- static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
-
- VLOG_ERR_RL(&rl, "discarding oversize datapath actions");
- ofpbuf_clear(&ctx.xout->odp_actions);
+ * can't hand them to the kernel directly. dpif_execute() can execute
+ * them one by one with help, so just mark the result as SLOW_ACTION to
+ * prevent the flow from being installed. */
+ COVERAGE_INC(xlate_actions_oversize);
+ ctx.xout->slow |= SLOW_ACTION;
}
ofpbuf_uninit(&ctx.stack);
--
1.7.10.4
_______________________________________________
dev mailing list
dev@openvswitch.org
http://openvswitch.org/mailman/listinfo/dev
