[ovs-dev,v3] ovs-dpctl: Add new command dpctl/ct-[sg]et-sweep-interval.

diff --git a/NEWS b/NEWS
index b6418c36e..1155bfbb1 100644
--- a/NEWS
+++ b/NEWS
@@ -11,6 +11,9 @@  Post-v3.1.0
    - ovs-appctl:
      * Add support for selecting the source address with the
        'ovs-appctl ovs/route/add' command.
+     * New commands "dpctl/{ct-get-sweep-interval,ct-set-sweep-interval}" that
+       allow to get and set, for the userspace datapath, the sweep interval
+       for the conntrack garbage collector.
    - ovs-ctl:
      * Added new options --[ovsdb-server|ovs-vswitchd]-umask=MODE to set umask
        value when starting OVS daemons.  E.g., use --ovsdb-server-umask=0002
diff --git a/lib/conntrack-private.h b/lib/conntrack-private.h
index fae8b3a9b..bb326868e 100644
--- a/lib/conntrack-private.h
+++ b/lib/conntrack-private.h
@@ -224,6 +224,7 @@  struct conntrack {
     struct ipf *ipf; /* Fragmentation handling context. */
     uint32_t zone_limit_seq; /* Used to disambiguate zone limit counts. */
     atomic_bool tcp_seq_chk; /* Check TCP sequence numbers. */
+    atomic_uint32_t sweep_ms; /* Next sweep interval. */
 };
 
 /* Lock acquisition order:
diff --git a/lib/conntrack.c b/lib/conntrack.c
index f86fa26f4..ce8a63de5 100644
--- a/lib/conntrack.c
+++ b/lib/conntrack.c
@@ -320,6 +320,7 @@  conntrack_init(void)
     atomic_count_init(&ct->n_conn, 0);
     atomic_init(&ct->n_conn_limit, DEFAULT_N_CONN_LIMIT);
     atomic_init(&ct->tcp_seq_chk, true);
+    atomic_init(&ct->sweep_ms, 20000);
     latch_init(&ct->clean_thread_exit);
     ct->clean_thread = ovs_thread_create("ct_clean", clean_thread_main, ct);
     ct->ipf = ipf_init();
@@ -1480,6 +1481,21 @@  set_label(struct dp_packet *pkt, struct conn *conn,
 }
 
 
+int
+conntrack_set_sweep_interval(struct conntrack *ct, uint32_t ms)
+{
+    atomic_store_relaxed(&ct->sweep_ms, ms);
+    return 0;
+}
+
+uint32_t
+conntrack_get_sweep_interval(struct conntrack *ct)
+{
+    uint32_t ms;
+    atomic_read_relaxed(&ct->sweep_ms, &ms);
+    return ms;
+}
+
 static size_t
 ct_sweep(struct conntrack *ct, struct rculist *list, long long now)
     OVS_NO_THREAD_SAFETY_ANALYSIS
@@ -1504,7 +1520,7 @@  ct_sweep(struct conntrack *ct, struct rculist *list, long long now)
 static long long
 conntrack_clean(struct conntrack *ct, long long now)
 {
-    long long next_wakeup = now + 20 * 1000;
+    long long next_wakeup = now + conntrack_get_sweep_interval(ct);
     unsigned int n_conn_limit, i;
     size_t clean_end, count = 0;
 
diff --git a/lib/conntrack.h b/lib/conntrack.h
index b064abc9f..524ec0acb 100644
--- a/lib/conntrack.h
+++ b/lib/conntrack.h
@@ -139,6 +139,8 @@  int conntrack_set_maxconns(struct conntrack *ct, uint32_t maxconns);
 int conntrack_get_maxconns(struct conntrack *ct, uint32_t *maxconns);
 int conntrack_get_nconns(struct conntrack *ct, uint32_t *nconns);
 int conntrack_set_tcp_seq_chk(struct conntrack *ct, bool enabled);
+int conntrack_set_sweep_interval(struct conntrack *ct, uint32_t ms);
+uint32_t conntrack_get_sweep_interval(struct conntrack *ct);
 bool conntrack_get_tcp_seq_chk(struct conntrack *ct);
 struct ipf *conntrack_ipf_ctx(struct conntrack *ct);
 struct conntrack_zone_limit zone_limit_get(struct conntrack *ct,
diff --git a/lib/ct-dpif.c b/lib/ct-dpif.c
index d3b2783ce..0c4b2964f 100644
--- a/lib/ct-dpif.c
+++ b/lib/ct-dpif.c
@@ -368,6 +368,20 @@  ct_dpif_del_limits(struct dpif *dpif, const struct ovs_list *zone_limits)
             : EOPNOTSUPP);
 }
 
+int
+ct_dpif_sweep(struct dpif *dpif, uint32_t *ms)
+{
+    if (*ms) {
+        return (dpif->dpif_class->ct_set_sweep_interval
+                ? dpif->dpif_class->ct_set_sweep_interval(dpif, *ms)
+                : EOPNOTSUPP);
+    } else {
+        return (dpif->dpif_class->ct_get_sweep_interval
+                ? dpif->dpif_class->ct_get_sweep_interval(dpif, ms)
+                : EOPNOTSUPP);
+    }
+}
+
 int
 ct_dpif_ipf_set_enabled(struct dpif *dpif, bool v6, bool enable)
 {
diff --git a/lib/ct-dpif.h b/lib/ct-dpif.h
index 5edbbfd3b..1e265604f 100644
--- a/lib/ct-dpif.h
+++ b/lib/ct-dpif.h
@@ -298,6 +298,7 @@  int ct_dpif_set_limits(struct dpif *dpif, const uint32_t *default_limit,
 int ct_dpif_get_limits(struct dpif *dpif, uint32_t *default_limit,
                        const struct ovs_list *, struct ovs_list *);
 int ct_dpif_del_limits(struct dpif *dpif, const struct ovs_list *);
+int ct_dpif_sweep(struct dpif *dpif, uint32_t *ms);
 int ct_dpif_ipf_set_enabled(struct dpif *, bool v6, bool enable);
 int ct_dpif_ipf_set_min_frag(struct dpif *, bool v6, uint32_t min_frag);
 int ct_dpif_ipf_set_max_nfrags(struct dpif *, uint32_t max_frags);
diff --git a/lib/dpctl.c b/lib/dpctl.c
index 59cc4f58c..3ba40fa8f 100644
--- a/lib/dpctl.c
+++ b/lib/dpctl.c
@@ -2300,6 +2300,65 @@  out:
     return error;
 }
 
+static int
+dpctl_ct_get_sweep(int argc, const char *argv[],
+                   struct dpctl_params *dpctl_p)
+{
+    uint32_t sweep_ms = 0;
+    struct dpif *dpif;
+
+    int error = opt_dpif_open(argc, argv, dpctl_p, 2, &dpif);
+    if (error) {
+        return error;
+    }
+
+    error = ct_dpif_sweep(dpif, &sweep_ms);
+    if (error) {
+        dpctl_error(dpctl_p, error, "failed to get the sweep interval");
+    } else {
+        dpctl_print(dpctl_p, "%"PRIu32, sweep_ms);
+    }
+
+    dpif_close(dpif);
+    return error;
+}
+
+static int
+dpctl_ct_set_sweep(int argc, const char *argv[],
+                   struct dpctl_params *dpctl_p)
+{
+    struct ds ds = DS_EMPTY_INITIALIZER;
+    uint32_t sweep_ms = 0;
+    struct dpif *dpif;
+
+    int error = opt_dpif_open(argc, argv, dpctl_p, 3, &dpif);
+    if (error) {
+        return error;
+    }
+
+    if (!ovs_scan(argv[argc - 1], "%"SCNu32, &sweep_ms) ||
+        sweep_ms == 0) {
+        ds_put_format(&ds, "invalid sweep value");
+        error = EINVAL;
+        goto error;
+    }
+
+    error = ct_dpif_sweep(dpif, &sweep_ms);
+    if (!error) {
+        dpctl_print(dpctl_p, "setting sweep interval successful\n");
+        goto out;
+    }
+
+    ds_put_format(&ds, "failed to set the sweep interval");
+
+error:
+    dpctl_error(dpctl_p, error, "%s", ds_cstr(&ds));
+    ds_destroy(&ds);
+out:
+    dpif_close(dpif);
+    return error;
+}
+
 static int
 ipf_set_enabled__(int argc, const char *argv[], struct dpctl_params *dpctl_p,
                   bool enabled)
@@ -2913,6 +2972,8 @@  static const struct dpctl_command all_commands[] = {
         DP_RO },
     { "ct-get-limits", "[dp] [zone=N1[,N2]...]", 0, 2, dpctl_ct_get_limits,
         DP_RO },
+    { "ct-get-sweep-interval", "[dp]", 0, 1, dpctl_ct_get_sweep, DP_RO },
+    { "ct-set-sweep-interval", "[dp] ms", 1, 2, dpctl_ct_set_sweep, DP_RW },
     { "ipf-set-enabled", "[dp] v4|v6", 1, 2, dpctl_ipf_set_enabled, DP_RW },
     { "ipf-set-disabled", "[dp] v4|v6", 1, 2, dpctl_ipf_set_disabled, DP_RW },
     { "ipf-set-min-frag", "[dp] v4|v6 minfragment", 2, 3,
diff --git a/lib/dpctl.man b/lib/dpctl.man
index 920446e8c..d448596d3 100644
--- a/lib/dpctl.man
+++ b/lib/dpctl.man
@@ -382,6 +382,15 @@  Prints whether TCP sequence checking is enabled or disabled on \fIdp\fR.  Only
 supported for the userspace datapath.
 .
 .TP
+\*(DX\fBct\-set\-sweep\-interval\fR [\fIdp\fR] \fIms\fR
+Sets the sweep interval. Only supported for the userspace datapath.
+.
+.TP
+\*(DX\fBct\-get\-sweep\-interval\fR [\fIdp\fR]
+Prints the current sweep interval in ms. Only supported for the userspace
+datapath.
+.
+.TP
 \*(DX\fBct\-set\-limits\fR [\fIdp\fR] [\fBdefault=\fIdefault_limit\fR] [\fBzone=\fIzone\fR,\fBlimit=\fIlimit\fR]...
 Sets the maximum allowed number of connections in a connection tracking
 zone.  A specific \fIzone\fR may be set to \fIlimit\fR, and multiple zones
diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
index aed2c8fbb..70b953ae6 100644
--- a/lib/dpif-netdev.c
+++ b/lib/dpif-netdev.c
@@ -9317,6 +9317,21 @@  dpif_netdev_ct_get_tcp_seq_chk(struct dpif *dpif, bool *enabled)
     return 0;
 }
 
+static int
+dpif_netdev_ct_set_sweep_interval(struct dpif *dpif, uint32_t ms)
+{
+    struct dp_netdev *dp = get_dp_netdev(dpif);
+    return conntrack_set_sweep_interval(dp->conntrack, ms);
+}
+
+static int
+dpif_netdev_ct_get_sweep_interval(struct dpif *dpif, uint32_t *ms)
+{
+    struct dp_netdev *dp = get_dp_netdev(dpif);
+    *ms = conntrack_get_sweep_interval(dp->conntrack);
+    return 0;
+}
+
 static int
 dpif_netdev_ct_set_limits(struct dpif *dpif,
                            const uint32_t *default_limits,
@@ -9668,6 +9683,8 @@  const struct dpif_class dpif_netdev_class = {
     dpif_netdev_ct_get_nconns,
     dpif_netdev_ct_set_tcp_seq_chk,
     dpif_netdev_ct_get_tcp_seq_chk,
+    dpif_netdev_ct_set_sweep_interval,
+    dpif_netdev_ct_get_sweep_interval,
     dpif_netdev_ct_set_limits,
     dpif_netdev_ct_get_limits,
     dpif_netdev_ct_del_limits,
diff --git a/lib/dpif-netlink.c b/lib/dpif-netlink.c
index 55b5b0a85..de0711277 100644
--- a/lib/dpif-netlink.c
+++ b/lib/dpif-netlink.c
@@ -4572,6 +4572,8 @@  const struct dpif_class dpif_netlink_class = {
     NULL,                       /* ct_get_nconns */
     NULL,                       /* ct_set_tcp_seq_chk */
     NULL,                       /* ct_get_tcp_seq_chk */
+    NULL,                       /* ct_set_sweep_interval */
+    NULL,                       /* ct_get_sweep_interval */
     dpif_netlink_ct_set_limits,
     dpif_netlink_ct_get_limits,
     dpif_netlink_ct_del_limits,
diff --git a/lib/dpif-provider.h b/lib/dpif-provider.h
index b8ead8a02..44d799198 100644
--- a/lib/dpif-provider.h
+++ b/lib/dpif-provider.h
@@ -493,6 +493,10 @@  struct dpif_class {
     int (*ct_set_tcp_seq_chk)(struct dpif *, bool enabled);
     /* Get the TCP sequence checking configuration. */
     int (*ct_get_tcp_seq_chk)(struct dpif *, bool *enabled);
+    /* Updates the sweep interval for the CT sweeper */
+    int (*ct_set_sweep_interval)(struct dpif *, uint32_t ms);
+    /* Get the current value of the sweep interval for the CT sweeper */
+    int (*ct_get_sweep_interval)(struct dpif *, uint32_t *ms);
 
 
     /* Connection tracking per zone limit */
diff --git a/tests/ofproto-dpif.at b/tests/ofproto-dpif.at
index 222415ac0..d4d1d9fc1 100644
--- a/tests/ofproto-dpif.at
+++ b/tests/ofproto-dpif.at
@@ -11721,6 +11721,28 @@  AT_CHECK([tail -1 stdout], [0],
 OVS_VSWITCHD_STOP
 AT_CLEANUP
 
+dnl Checks the get/set sweep interval
+AT_SETUP([ofproto-dpif - conntrack - change sweep interval])
+OVS_VSWITCHD_START
+
+# Check the default value.
+AT_CHECK([ovs-appctl dpctl/ct-get-sweep-interval], [0], [dnl
+20000
+])
+
+# Set the interval to 5s.
+AT_CHECK([ovs-appctl dpctl/ct-set-sweep-interval 5000], [0], [dnl
+setting sweep interval successful
+])
+
+# Verify that the previous value has been applied.
+AT_CHECK([ovs-appctl dpctl/ct-get-sweep-interval], [0], [dnl
+5000
+])
+
+OVS_VSWITCHD_STOP
+AT_CLEANUP
+
 AT_SETUP([ofproto - set mtu])
 OVS_VSWITCHD_START