[ovs-dev] [PATCH] upcall: Simplify enable_ufid debug option.

[Joe Stringer]

We previously tracked the debug enable/disable of UFID in each udpif,
and allowed the ovs-appctl debug option to turn on UFID features even if
the datapath doesn't support it.

This commit shifts the enable_ufid debug flag to a single flag, and
provides a helper to determine whether UFID features should be used on a
per-udpif basis.

Suggested-by: Andy Zhou <azhou at nicira.com>
Signed-off-by: Joe Stringer <joestringer at nicira.com>
---
 ofproto/ofproto-dpif-upcall.c |   33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/ofproto/ofproto-dpif-upcall.c b/ofproto/ofproto-dpif-upcall.c
index 6feaa75..4a7a829 100644
--- a/ofproto/ofproto-dpif-upcall.c
+++ b/ofproto/ofproto-dpif-upcall.c
@@ -294,6 +294,7 @@ static void upcall_uninit(struct upcall *);
 static upcall_callback upcall_cb;
 
 static atomic_bool enable_megaflows = ATOMIC_VAR_INIT(true);
+static atomic_bool enable_ufid = ATOMIC_VAR_INIT(true);
 
 struct udpif *
 udpif_create(struct dpif_backer *backer, struct dpif *dpif)
@@ -573,6 +574,15 @@ udpif_flush_all_datapaths(void)
     }
 }
 
+static bool
+udpif_use_ufid(struct udpif *udpif)
+{
+    bool enable;
+
+    atomic_read_relaxed(&enable_ufid, &enable);
+    return enable && ofproto_dpif_get_enable_ufid(udpif->backer);
+}
+
 
 static unsigned long
 udpif_get_n_flows(struct udpif *udpif)
@@ -742,7 +752,7 @@ udpif_revalidator(void *arg)
             if (!udpif->reval_exit) {
                 bool terse_dump;
 
-                atomic_read_relaxed(&udpif->enable_ufid, &terse_dump);
+                terse_dump = udpif_use_ufid(udpif);
                 udpif->dump = dpif_flow_dump_create(udpif->dpif, terse_dump);
             }
         }
@@ -1684,7 +1694,7 @@ delete_op_init__(struct udpif *udpif, struct ukey_op *op,
     op->dop.u.flow_del.key_len = flow->key_len;
     op->dop.u.flow_del.ufid = flow->ufid_present ? &flow->ufid : NULL;
     op->dop.u.flow_del.stats = &op->stats;
-    atomic_read_relaxed(&udpif->enable_ufid, &op->dop.u.flow_del.terse);
+    op->dop.u.flow_del.terse = udpif_use_ufid(udpif);
 }
 
 static void
@@ -1696,7 +1706,7 @@ delete_op_init(struct udpif *udpif, struct ukey_op *op, struct udpif_key *ukey)
     op->dop.u.flow_del.key_len = ukey->key_len;
     op->dop.u.flow_del.ufid = ukey->ufid_present ? &ukey->ufid : NULL;
     op->dop.u.flow_del.stats = &op->stats;
-    atomic_read_relaxed(&udpif->enable_ufid, &op->dop.u.flow_del.terse);
+    op->dop.u.flow_del.terse = udpif_use_ufid(udpif);
 }
 
 static void
@@ -2007,7 +2017,7 @@ upcall_unixctl_show(struct unixctl_conn *conn, int argc OVS_UNUSED,
         size_t i;
 
         atomic_read_relaxed(&udpif->flow_limit, &flow_limit);
-        atomic_read_relaxed(&udpif->enable_ufid, &ufid_enabled);
+        ufid_enabled = udpif_use_ufid(udpif);
 
         ds_put_format(&ds, "%s:\n", dpif_name(udpif->dpif));
         ds_put_format(&ds, "\tflows         : (current %lu)"
@@ -2075,11 +2085,7 @@ static void
 upcall_unixctl_disable_ufid(struct unixctl_conn *conn, int argc OVS_UNUSED,
                            const char *argv[] OVS_UNUSED, void *aux OVS_UNUSED)
 {
-    struct udpif *udpif;
-
-    LIST_FOR_EACH (udpif, list_node, &all_udpifs) {
-        atomic_store(&udpif->enable_ufid, false);
-    }
+    atomic_store_relaxed(&enable_ufid, false);
     unixctl_command_reply(conn, "Datapath dumping tersely using UFID disabled");
 }
 
@@ -2091,12 +2097,9 @@ static void
 upcall_unixctl_enable_ufid(struct unixctl_conn *conn, int argc OVS_UNUSED,
                           const char *argv[] OVS_UNUSED, void *aux OVS_UNUSED)
 {
-    struct udpif *udpif;
-
-    LIST_FOR_EACH (udpif, list_node, &all_udpifs) {
-        atomic_store(&udpif->enable_ufid, true);
-    }
-    unixctl_command_reply(conn, "Datapath dumping tersely using UFID enabled");
+    atomic_store_relaxed(&enable_ufid, true);
+    unixctl_command_reply(conn, "Datapath dumping tersely using UFID enabled "
+                                "for supported datapaths");
 }
 
 /* Set the flow limit.
-- 
1.7.10.4