netdev-dpdk: Add new DPDK RFC 4115 egress policer

This patch adds a new policer to the DPDK datapath based on RFC 4115's
Two-Rate, Three-Color marker. It's a two-level hierarchical policer
which first does a color-blind marking of the traffic at the queue
level, followed by a color-aware marking at the port level. At the end
traffic marked as Green or Yellow is forwarded, Red is dropped. For
details on how traffic is marked, see RFC 4115.

This egress policer can be used to limit traffic at different rated
based on the queues the traffic is in. In addition, it can also be used
to prioritize certain traffic over others at a port level.

For example, the following configuration will limit the traffic rate at a
port level to a maximum of 2000 packets a second (64 bytes IPv4 packets).
100pps as CIR (Committed Information Rate) and 1000pps as EIR (Excess
Information Rate). High priority traffic is routed to queue 10, which marks
all traffic as CIR, i.e. Green. All low priority traffic, queue 20, is
marked as EIR, i.e. Yellow.

ovs-vsctl --timeout=5 set port dpdk1 qos=@myqos -- \
  --id=@myqos create qos type=trtcm-policer \
  other-config:cir=52000 other-config:cbs=2048 \
  other-config:eir=52000 other-config:ebs=2048  \
  queues:10=@dpdk1Q10 queues:20=@dpdk1Q20 -- \
  --id=@dpdk1Q10 create queue \
    other-config:cir=41600000 other-config:cbs=2048 \
    other-config:eir=0 other-config:ebs=0 -- \
  --id=@dpdk1Q20 create queue \
    other-config:cir=0 other-config:cbs=0 \
    other-config:eir=41600000 other-config:ebs=2048 \

This configuration accomplishes that the high priority traffic has a
guaranteed bandwidth egressing the ports at CIR (1000pps), but it can also
use the EIR, so a total of 2000pps at max. These additional 1000pps is
shared with the low priority traffic. The low priority traffic can use at
maximum 1000pps.

Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Ian Stokes <ian.stokes@intel.com>

3 files changed, 421 insertions, 15 deletions

diff --git a/Documentation/topics/dpdk/qos.rst b/Documentation/topics/dpdk/qos.rst
index c0aec5d88..103495415 100644
--- a/Documentation/topics/dpdk/qos.rst
+++ b/Documentation/topics/dpdk/qos.rst
@@ -33,6 +33,9 @@ datapath. These are referred to as *QoS* and *Rate Limiting*, respectively.
 QoS (Egress Policing)
 ---------------------
 
+Single Queue Policer
+~~~~~~~~~~~~~~~~~~~~
+
 Assuming you have a :doc:`vhost-user port <vhost-user>` transmitting traffic
 consisting of packets of size 64 bytes, the following command would limit the
 egress transmission rate of the port to ~1,000,000 packets per second::
@@ -49,6 +52,46 @@ To clear the QoS configuration from the port and ovsdb, run::
 
     $ ovs-vsctl destroy QoS vhost-user0 -- clear Port vhost-user0 qos
 
+
+Multi Queue Policer
+~~~~~~~~~~~~~~~~~~~
+
+In addition to the egress-policer OVS-DPDK also has support for a RFC
+4115's Two-Rate, Three-Color marker meter. It's a two-level hierarchical
+policer which first does a color-blind marking of the traffic at the queue
+level, followed by a color-aware marking at the port level. At the end
+traffic marked as Green or Yellow is forwarded, Red is dropped. For
+details on how traffic is marked, see RFC 4115.
+
+This egress policer can be used to limit traffic at different rated
+based on the queues the traffic is in. In addition, it can also be used
+to prioritize certain traffic over others at a port level.
+
+For example, the following configuration will limit the traffic rate at a
+port level to a maximum of 2000 packets a second (64 bytes IPv4 packets).
+100pps as CIR (Committed Information Rate) and 1000pps as EIR (Excess
+Information Rate). High priority traffic is routed to queue 10, which marks
+all traffic as CIR, i.e. Green. All low priority traffic, queue 20, is
+marked as EIR, i.e. Yellow::
+
+    $ ovs-vsctl --timeout=5 set port dpdk1 qos=@myqos -- \
+        --id=@myqos create qos type=trtcm-policer \
+        other-config:cir=52000 other-config:cbs=2048 \
+        other-config:eir=52000 other-config:ebs=2048  \
+        queues:10=@dpdk1Q10 queues:20=@dpdk1Q20 -- \
+         --id=@dpdk1Q10 create queue \
+          other-config:cir=41600000 other-config:cbs=2048 \
+          other-config:eir=0 other-config:ebs=0 -- \
+         --id=@dpdk1Q20 create queue \
+           other-config:cir=0 other-config:cbs=0 \
+           other-config:eir=41600000 other-config:ebs=2048 \
+
+This configuration accomplishes that the high priority traffic has a
+guaranteed bandwidth egressing the ports at CIR (1000pps), but it can also
+use the EIR, so a total of 2000pps at max. These additional 1000pps is
+shared with the low priority traffic. The low priority traffic can use at
+maximum 1000pps.
+
 Refer to ``vswitch.xml`` for more details on egress policer.
 
 Rate Limiting (Ingress Policing)
diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
index fccac64de..5ee9f9fbc 100644
--- a/lib/netdev-dpdk.c
+++ b/lib/netdev-dpdk.c
@@ -26,6 +26,12 @@
 #include <sys/socket.h>
 #include <linux/if.h>
 
+/* Include rte_compat.h first to allow experimental API's needed for the
+ * rte_meter.h rfc4115 functions. Once they are no longer marked as
+ * experimental the #define and rte_compat.h include can be removed.
+ */
+#define ALLOW_EXPERIMENTAL_API
+#include <rte_compat.h>
 #include <rte_bus_pci.h>
 #include <rte_config.h>
 #include <rte_cycles.h>
@@ -329,8 +335,9 @@ struct dpdk_qos_ops {
                                      struct netdev_dpdk_queue_state *state);
 };
 
-/* dpdk_qos_ops for each type of user space QoS implementation */
+/* dpdk_qos_ops for each type of user space QoS implementation. */
 static const struct dpdk_qos_ops egress_policer_ops;
+static const struct dpdk_qos_ops trtcm_policer_ops;
 
 /*
  * Array of dpdk_qos_ops, contains pointer to all supported QoS
@@ -338,6 +345,7 @@ static const struct dpdk_qos_ops egress_policer_ops;
  */
 static const struct dpdk_qos_ops *const qos_confs[] = {
     &egress_policer_ops,
+    &trtcm_policer_ops,
     NULL
 };
 
@@ -2162,9 +2170,9 @@ netdev_dpdk_eth_tx_burst(struct netdev_dpdk *dev, int qid,
 }
 
 static inline bool
-netdev_dpdk_policer_pkt_handle(struct rte_meter_srtcm *meter,
-                               struct rte_meter_srtcm_profile *profile,
-                               struct rte_mbuf *pkt, uint64_t time)
+netdev_dpdk_srtcm_policer_pkt_handle(struct rte_meter_srtcm *meter,
+                                     struct rte_meter_srtcm_profile *profile,
+                                     struct rte_mbuf *pkt, uint64_t time)
 {
     uint32_t pkt_len = rte_pktmbuf_pkt_len(pkt) - sizeof(struct rte_ether_hdr);
 
@@ -2173,10 +2181,10 @@ netdev_dpdk_policer_pkt_handle(struct rte_meter_srtcm *meter,
 }
 
 static int
-netdev_dpdk_policer_run(struct rte_meter_srtcm *meter,
-                        struct rte_meter_srtcm_profile *profile,
-                        struct rte_mbuf **pkts, int pkt_cnt,
-                        bool should_steal)
+srtcm_policer_run_single_packet(struct rte_meter_srtcm *meter,
+                                struct rte_meter_srtcm_profile *profile,
+                                struct rte_mbuf **pkts, int pkt_cnt,
+                                bool should_steal)
 {
     int i = 0;
     int cnt = 0;
@@ -2186,8 +2194,8 @@ netdev_dpdk_policer_run(struct rte_meter_srtcm *meter,
     for (i = 0; i < pkt_cnt; i++) {
         pkt = pkts[i];
         /* Handle current packet */
-        if (netdev_dpdk_policer_pkt_handle(meter, profile,
-                                           pkt, current_time)) {
+        if (netdev_dpdk_srtcm_policer_pkt_handle(meter, profile,
+                                                 pkt, current_time)) {
             if (cnt != i) {
                 pkts[cnt] = pkt;
             }
@@ -2209,8 +2217,9 @@ ingress_policer_run(struct ingress_policer *policer, struct rte_mbuf **pkts,
     int cnt = 0;
 
     rte_spinlock_lock(&policer->policer_lock);
-    cnt = netdev_dpdk_policer_run(&policer->in_policer, &policer->in_prof,
-                                  pkts, pkt_cnt, should_steal);
+    cnt = srtcm_policer_run_single_packet(&policer->in_policer,
+                                          &policer->in_prof,
+                                          pkts, pkt_cnt, should_steal);
     rte_spinlock_unlock(&policer->policer_lock);
 
     return cnt;
@@ -4480,9 +4489,9 @@ egress_policer_run(struct qos_conf *conf, struct rte_mbuf **pkts, int pkt_cnt,
     struct egress_policer *policer =
         CONTAINER_OF(conf, struct egress_policer, qos_conf);
 
-    cnt = netdev_dpdk_policer_run(&policer->egress_meter,
-                                  &policer->egress_prof, pkts,
-                                  pkt_cnt, should_steal);
+    cnt = srtcm_policer_run_single_packet(&policer->egress_meter,
+                                          &policer->egress_prof, pkts,
+                                          pkt_cnt, should_steal);
 
     return cnt;
 }
@@ -4496,6 +4505,326 @@ static const struct dpdk_qos_ops egress_policer_ops = {
     .qos_run = egress_policer_run
 };
 
+/* trtcm-policer details */
+
+struct trtcm_policer {
+    struct qos_conf qos_conf;
+    struct rte_meter_trtcm_rfc4115_params meter_params;
+    struct rte_meter_trtcm_rfc4115_profile meter_profile;
+    struct rte_meter_trtcm_rfc4115 meter;
+    struct netdev_queue_stats stats;
+    struct hmap queues;
+};
+
+struct trtcm_policer_queue {
+    struct hmap_node hmap_node;
+    uint32_t queue_id;
+    struct rte_meter_trtcm_rfc4115_params meter_params;
+    struct rte_meter_trtcm_rfc4115_profile meter_profile;
+    struct rte_meter_trtcm_rfc4115 meter;
+    struct netdev_queue_stats stats;
+};
+
+static void
+trtcm_policer_details_to_param(const struct smap *details,
+                               struct rte_meter_trtcm_rfc4115_params *params)
+{
+    memset(params, 0, sizeof *params);
+    params->cir = smap_get_ullong(details, "cir", 0);
+    params->eir = smap_get_ullong(details, "eir", 0);
+    params->cbs = smap_get_ullong(details, "cbs", 0);
+    params->ebs = smap_get_ullong(details, "ebs", 0);
+}
+
+static void
+trtcm_policer_param_to_detail(
+    const struct rte_meter_trtcm_rfc4115_params *params,
+    struct smap *details)
+{
+    smap_add_format(details, "cir", "%"PRIu64, params->cir);
+    smap_add_format(details, "eir", "%"PRIu64, params->eir);
+    smap_add_format(details, "cbs", "%"PRIu64, params->cbs);
+    smap_add_format(details, "ebs", "%"PRIu64, params->ebs);
+}
+
+
+static int
+trtcm_policer_qos_construct(const struct smap *details,
+                            struct qos_conf **conf)
+{
+    struct trtcm_policer *policer;
+    int err = 0;
+
+    policer = xmalloc(sizeof *policer);
+    qos_conf_init(&policer->qos_conf, &trtcm_policer_ops);
+    trtcm_policer_details_to_param(details, &policer->meter_params);
+    err = rte_meter_trtcm_rfc4115_profile_config(&policer->meter_profile,
+                                                 &policer->meter_params);
+    if (!err) {
+        err = rte_meter_trtcm_rfc4115_config(&policer->meter,
+                                             &policer->meter_profile);
+    }
+
+    if (!err) {
+        *conf = &policer->qos_conf;
+        memset(&policer->stats, 0, sizeof policer->stats);
+        hmap_init(&policer->queues);
+    } else {
+        free(policer);
+        *conf = NULL;
+        err = -err;
+    }
+
+    return err;
+}
+
+static void
+trtcm_policer_qos_destruct(struct qos_conf *conf)
+{
+    struct trtcm_policer_queue *queue, *next_queue;
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+
+    HMAP_FOR_EACH_SAFE (queue, next_queue, hmap_node, &policer->queues) {
+        hmap_remove(&policer->queues, &queue->hmap_node);
+        free(queue);
+    }
+    hmap_destroy(&policer->queues);
+    free(policer);
+}
+
+static int
+trtcm_policer_qos_get(const struct qos_conf *conf, struct smap *details)
+{
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+
+    trtcm_policer_param_to_detail(&policer->meter_params, details);
+    return 0;
+}
+
+static bool
+trtcm_policer_qos_is_equal(const struct qos_conf *conf,
+                           const struct smap *details)
+{
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+    struct rte_meter_trtcm_rfc4115_params params;
+
+    trtcm_policer_details_to_param(details, &params);
+
+    return !memcmp(&params, &policer->meter_params, sizeof params);
+}
+
+static struct trtcm_policer_queue *
+trtcm_policer_qos_find_queue(struct trtcm_policer *policer, uint32_t queue_id)
+{
+    struct trtcm_policer_queue *queue;
+    HMAP_FOR_EACH_WITH_HASH (queue, hmap_node, hash_2words(queue_id, 0),
+                             &policer->queues) {
+        if (queue->queue_id == queue_id) {
+            return queue;
+        }
+    }
+    return NULL;
+}
+
+static inline bool
+trtcm_policer_run_single_packet(struct trtcm_policer *policer,
+                                struct rte_mbuf *pkt, uint64_t time)
+{
+    enum rte_color pkt_color;
+    struct trtcm_policer_queue *queue;
+    uint32_t pkt_len = rte_pktmbuf_pkt_len(pkt) - sizeof(struct rte_ether_hdr);
+    struct dp_packet *dpkt = CONTAINER_OF(pkt, struct dp_packet, mbuf);
+
+    queue = trtcm_policer_qos_find_queue(policer, dpkt->md.skb_priority);
+    if (!queue) {
+        /* If no queue is found, use the default queue, which MUST exist. */
+        queue = trtcm_policer_qos_find_queue(policer, 0);
+        if (!queue) {
+            return false;
+        }
+    }
+
+    pkt_color = rte_meter_trtcm_rfc4115_color_blind_check(&queue->meter,
+                                                          &queue->meter_profile,
+                                                          time,
+                                                          pkt_len);
+
+    if (pkt_color == RTE_COLOR_RED) {
+        queue->stats.tx_errors++;
+    } else {
+        queue->stats.tx_bytes += pkt_len;
+        queue->stats.tx_packets++;
+    }
+
+    pkt_color = rte_meter_trtcm_rfc4115_color_aware_check(&policer->meter,
+                                                     &policer->meter_profile,
+                                                     time, pkt_len,
+                                                     pkt_color);
+
+    if (pkt_color == RTE_COLOR_RED) {
+        policer->stats.tx_errors++;
+        return false;
+    }
+
+    policer->stats.tx_bytes += pkt_len;
+    policer->stats.tx_packets++;
+    return true;
+}
+
+static int
+trtcm_policer_run(struct qos_conf *conf, struct rte_mbuf **pkts, int pkt_cnt,
+                  bool should_steal)
+{
+    int i = 0;
+    int cnt = 0;
+    struct rte_mbuf *pkt = NULL;
+    uint64_t current_time = rte_rdtsc();
+
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+
+    for (i = 0; i < pkt_cnt; i++) {
+        pkt = pkts[i];
+
+        if (trtcm_policer_run_single_packet(policer, pkt, current_time)) {
+            if (cnt != i) {
+                pkts[cnt] = pkt;
+            }
+            cnt++;
+        } else {
+            if (should_steal) {
+                rte_pktmbuf_free(pkt);
+            }
+        }
+    }
+    return cnt;
+}
+
+static int
+trtcm_policer_qos_queue_construct(const struct smap *details,
+                                  uint32_t queue_id, struct qos_conf *conf)
+{
+    int err = 0;
+    struct trtcm_policer_queue *queue;
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+
+    queue = trtcm_policer_qos_find_queue(policer, queue_id);
+    if (!queue) {
+        queue = xmalloc(sizeof *queue);
+        queue->queue_id = queue_id;
+        memset(&queue->stats, 0, sizeof queue->stats);
+        queue->stats.created = time_msec();
+        hmap_insert(&policer->queues, &queue->hmap_node,
+                    hash_2words(queue_id, 0));
+    }
+    if (queue_id == 0 && smap_is_empty(details)) {
+        /* No default queue configured, use port values */
+        memcpy(&queue->meter_params, &policer->meter_params,
+               sizeof queue->meter_params);
+    } else {
+        trtcm_policer_details_to_param(details, &queue->meter_params);
+    }
+
+    err = rte_meter_trtcm_rfc4115_profile_config(&queue->meter_profile,
+                                                 &queue->meter_params);
+
+    if (!err) {
+        err = rte_meter_trtcm_rfc4115_config(&queue->meter,
+                                             &queue->meter_profile);
+    }
+    if (err) {
+        hmap_remove(&policer->queues, &queue->hmap_node);
+        free(queue);
+        err = -err;
+    }
+    return err;
+}
+
+static void
+trtcm_policer_qos_queue_destruct(struct qos_conf *conf, uint32_t queue_id)
+{
+    struct trtcm_policer_queue *queue;
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+
+    queue = trtcm_policer_qos_find_queue(policer, queue_id);
+    if (queue) {
+        hmap_remove(&policer->queues, &queue->hmap_node);
+        free(queue);
+    }
+}
+
+static int
+trtcm_policer_qos_queue_get(struct smap *details, uint32_t queue_id,
+                            const struct qos_conf *conf)
+{
+    struct trtcm_policer_queue *queue;
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+
+    queue = trtcm_policer_qos_find_queue(policer, queue_id);
+    if (!queue) {
+        return EINVAL;
+    }
+
+    trtcm_policer_param_to_detail(&queue->meter_params, details);
+    return 0;
+}
+
+static int
+trtcm_policer_qos_queue_get_stats(const struct qos_conf *conf,
+                                  uint32_t queue_id,
+                                  struct netdev_queue_stats *stats)
+{
+    struct trtcm_policer_queue *queue;
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+
+    queue = trtcm_policer_qos_find_queue(policer, queue_id);
+    if (!queue) {
+        return EINVAL;
+    }
+    memcpy(stats, &queue->stats, sizeof *stats);
+    return 0;
+}
+
+static int
+trtcm_policer_qos_queue_dump_state_init(const struct qos_conf *conf,
+                                        struct netdev_dpdk_queue_state *state)
+{
+    uint32_t i = 0;
+    struct trtcm_policer_queue *queue;
+    struct trtcm_policer *policer = CONTAINER_OF(conf, struct trtcm_policer,
+                                                 qos_conf);
+
+    state->n_queues = hmap_count(&policer->queues);
+    state->cur_queue = 0;
+    state->queues = xmalloc(state->n_queues * sizeof *state->queues);
+
+    HMAP_FOR_EACH (queue, hmap_node, &policer->queues) {
+        state->queues[i++] = queue->queue_id;
+    }
+    return 0;
+}
+
+static const struct dpdk_qos_ops trtcm_policer_ops = {
+    .qos_name = "trtcm-policer",
+    .qos_construct = trtcm_policer_qos_construct,
+    .qos_destruct = trtcm_policer_qos_destruct,
+    .qos_get = trtcm_policer_qos_get,
+    .qos_is_equal = trtcm_policer_qos_is_equal,
+    .qos_run = trtcm_policer_run,
+    .qos_queue_construct = trtcm_policer_qos_queue_construct,
+    .qos_queue_destruct = trtcm_policer_qos_queue_destruct,
+    .qos_queue_get = trtcm_policer_qos_queue_get,
+    .qos_queue_get_stats = trtcm_policer_qos_queue_get_stats,
+    .qos_queue_dump_state_init = trtcm_policer_qos_queue_dump_state_init
+};
+
 static int
 netdev_dpdk_reconfigure(struct netdev *netdev)
 {
diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml
index 0ec726c39..c43cb1aa4 100644
--- a/vswitchd/vswitch.xml
+++ b/vswitchd/vswitch.xml
@@ -4441,6 +4441,19 @@ ovs-vsctl add-port br0 p0 -- set Interface p0 type=patch options:peer=p1 \
           in performance will be noticed in terms of overall aggregate traffic
           throughput.
         </dd>
+        <dt><code>trtcm-policer</code></dt>
+        <dd>
+          A DPDK egress policer algorithm using RFC 4115's Two-Rate,
+          Three-Color marker. It's a two-level hierarchical policer
+          which first does a color-blind marking of the traffic at the queue
+          level, followed by a color-aware marking at the port level. At the
+          end traffic marked as Green or Yellow is forwarded, Red is dropped.
+          For details on how traffic is marked, see RFC 4115.
+
+          If the ``default queue'', 0, is not configured it's automatically
+          created with the same <code>other_config</code> values as the
+          physical port.
+        </dd>
       </dl>
     </column>
 
@@ -4508,6 +4521,27 @@ ovs-vsctl add-port br0 p0 -- set Interface p0 type=patch options:peer=p1 \
         bytes/tokens of the packet. If there are not enough tokens in the cbs
         bucket the packet will be dropped.
       </column>
+      <column name="other_config" key="eir" type='{"type": "integer"}'>
+        The Excess Information Rate (EIR) is measured in bytes of IP
+        packets per second, i.e. it includes the IP header, but not link
+        specific (e.g. Ethernet) headers. This represents the bytes per second
+        rate at which the token bucket will be updated. The eir value is
+        calculated by (pps x packet data size).  For example assuming a user
+        wishes to limit a stream consisting of 64 byte packets to 1 million
+        packets per second the EIR would be set to to to 46000000. This value
+        can be broken into '1,000,000 x 46'. Where 1,000,000 is the policing
+        rate for the number of packets per second and 46 represents the size
+        of the packet data for a 64 byte ip packet.
+      </column>
+      <column name="other_config" key="ebs" type='{"type": "integer"}'>
+        The Excess Burst Size (EBS) is measured in bytes and represents a
+        token bucket. At a minimum this value should be be set to the expected
+        largest size packet in the traffic stream. In practice larger values
+        may be used to increase the size of the token bucket. If a packet can
+        be transmitted then the ebs will be decremented by the number of
+        bytes/tokens of the packet. If there are not enough tokens in the cbs
+        bucket the packet might be dropped.
+      </column>
     </group>
 
     <group title="Configuration for linux-sfq">