network: TC - introduce fq pie

see https://patchwork.ozlabs.org/patch/1233253/

man/systemd.network.xml

@@ -2823,6 +2823,25 @@ IPv6Token=prefixstable:2002:da8:1::</programlisting></para>
     </variablelist>
   </refsect1>
 
+  <refsect1>
+    <title>[FlowQueuePIE] Section Options</title>
+    <para>The <literal>[FlowQueuePIE]</literal> section manages the queueing discipline
+    (qdisc) of Flow Queue Proportional Integral controller-Enhanced (fq_pie).</para>
+
+    <variablelist class='network-directives'>
+      <xi:include href="tc.xml" xpointer="qdisc-parent" />
+      <xi:include href="tc.xml" xpointer="qdisc-handle" />
+
+      <varlistentry>
+        <term><varname>PacketLimit=</varname></term>
+        <listitem>
+          <para>Specifies the hard limit on the queue size in number of packets. When this limit is reached, incoming packets are
+          dropped. An unsigned integer ranges 1 to 4294967294. Defaults to unset and kernel's default is used.</para>
+        </listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
+
   <refsect1>
     <title>[StochasticFairBlue] Section Options</title>
     <para>The [StochasticFairBlue] section manages the queueing discipline (qdisc) of stochastic fair blue

src/network/meson.build

@@ -127,6 +127,8 @@ sources = files('''
         tc/fq.h
         tc/fq-codel.c
         tc/fq-codel.h
+        tc/fq-pie.c
+        tc/fq-pie.h
         tc/gred.c
         tc/gred.h
         tc/hhf.c

src/network/networkd-network-gperf.gperf

@@ -364,6 +364,9 @@ FairQueueingControlledDelay.TargetSec,       config_parse_fair_queueing_controll
 FairQueueingControlledDelay.IntervalSec,     config_parse_fair_queueing_controlled_delay_usec,         QDISC_KIND_FQ_CODEL,           0
 FairQueueingControlledDelay.CEThresholdSec,  config_parse_fair_queueing_controlled_delay_usec,         QDISC_KIND_FQ_CODEL,           0
 FairQueueingControlledDelay.ECN,             config_parse_fair_queueing_controlled_delay_bool,         QDISC_KIND_FQ_CODEL,           0
+FlowQueuePIE.Parent,                         config_parse_qdisc_parent,                                QDISC_KIND_FQ_PIE,             0
+FlowQueuePIE.Handle,                         config_parse_qdisc_handle,                                QDISC_KIND_FQ_PIE,             0
+FlowQueuePIE.PacketLimit,                    config_parse_fq_pie_packet_limit,                         QDISC_KIND_FQ_PIE,             0
 GenericRandomEarlyDetection.Parent,          config_parse_qdisc_parent,                                QDISC_KIND_GRED,               0
 GenericRandomEarlyDetection.Handle,          config_parse_qdisc_handle,                                QDISC_KIND_GRED,               0
 GenericRandomEarlyDetection.VirtualQueues,   config_parse_generic_random_early_detection_u32,          QDISC_KIND_GRED,               0

src/network/networkd-network.c

@@ -538,6 +538,7 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                         "EnhancedTransmissionSelection\0"
                         "FairQueueing\0"
                         "FairQueueingControlledDelay\0"
+                        "FlowQueuePIE\0"
                         "GenericRandomEarlyDetection\0"
                         "HeavyHitterFilter\0"
                         "HierarchyTokenBucket\0"

src/network/tc/fq-pie.c

@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: LGPL-2.1+
+ * Copyright © 2020 VMware, Inc. */
+
+#include <linux/pkt_sched.h>
+
+#include "alloc-util.h"
+#include "conf-parser.h"
+#include "fq-pie.h"
+#include "netlink-util.h"
+#include "parse-util.h"
+#include "string-util.h"
+
+static int fq_pie_fill_message(Link *link, QDisc *qdisc, sd_netlink_message *req) {
+        FlowQueuePIE *fq_pie;
+        int r;
+
+        assert(link);
+        assert(qdisc);
+        assert(req);
+
+        fq_pie = FQ_PIE(qdisc);
+
+        r = sd_netlink_message_open_container_union(req, TCA_OPTIONS, "fq_pie");
+        if (r < 0)
+                return log_link_error_errno(link, r, "Could not open container TCA_OPTIONS: %m");
+
+        if (fq_pie->packet_limit > 0) {
+                r = sd_netlink_message_append_u32(req, TCA_FQ_PIE_LIMIT, fq_pie->packet_limit);
+                if (r < 0)
+                        return log_link_error_errno(link, r, "Could not append TCA_FQ_PIE_PLIMIT attribute: %m");
+        }
+
+        r = sd_netlink_message_close_container(req);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Could not close container TCA_OPTIONS: %m");
+
+        return 0;
+}
+
+int config_parse_fq_pie_packet_limit(
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                unsigned section_line,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+
+        _cleanup_(qdisc_free_or_set_invalidp) QDisc *qdisc = NULL;
+        FlowQueuePIE *fq_pie;
+        Network *network = data;
+        int r;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        r = qdisc_new_static(QDISC_KIND_FQ_PIE, network, filename, section_line, &qdisc);
+        if (r == -ENOMEM)
+                return log_oom();
+        if (r < 0)
+                return log_syntax(unit, LOG_WARNING, filename, line, r,
+                                  "More than one kind of queueing discipline, ignoring assignment: %m");
+
+        fq_pie = FQ_PIE(qdisc);
+
+        if (isempty(rvalue)) {
+                fq_pie->packet_limit = 0;
+
+                qdisc = NULL;
+                return 0;
+        }
+
+        r = safe_atou32(rvalue, &fq_pie->packet_limit);
+        if (r < 0) {
+                log_syntax(unit, LOG_WARNING, filename, line, r,
+                           "Failed to parse '%s=', ignoring assignment: %s",
+                           lvalue, rvalue);
+                return 0;
+        }
+
+        qdisc = NULL;
+
+        return 0;
+}
+
+const QDiscVTable fq_pie_vtable = {
+        .object_size = sizeof(FlowQueuePIE),
+        .tca_kind = "fq_pie",
+        .fill_message = fq_pie_fill_message,
+};

src/network/tc/fq-pie.h

@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: LGPL-2.1+
+ * Copyright © 2020 VMware, Inc. */
+#pragma once
+
+#include "conf-parser.h"
+#include "qdisc.h"
+
+typedef struct FlowQueuePIE {
+        QDisc meta;
+
+        uint32_t packet_limit;
+} FlowQueuePIE;
+
+DEFINE_QDISC_CAST(FQ_PIE, FlowQueuePIE);
+extern const QDiscVTable fq_pie_vtable;
+
+CONFIG_PARSER_PROTOTYPE(config_parse_fq_pie_packet_limit);

src/network/tc/qdisc.c

@@ -23,6 +23,7 @@ const QDiscVTable * const qdisc_vtable[_QDISC_KIND_MAX] = {
         [QDISC_KIND_ETS] = &ets_vtable,
         [QDISC_KIND_FQ] = &fq_vtable,
         [QDISC_KIND_FQ_CODEL] = &fq_codel_vtable,
+        [QDISC_KIND_FQ_PIE] = &fq_pie_vtable,
         [QDISC_KIND_GRED] = &gred_vtable,
         [QDISC_KIND_HHF] = &hhf_vtable,
         [QDISC_KIND_HTB] = &htb_vtable,

src/network/tc/qdisc.h

@@ -16,6 +16,7 @@ typedef enum QDiscKind {
         QDISC_KIND_ETS,
         QDISC_KIND_FQ,
         QDISC_KIND_FQ_CODEL,
+        QDISC_KIND_FQ_PIE,
         QDISC_KIND_GRED,
         QDISC_KIND_HHF,
         QDISC_KIND_HTB,
@@ -91,6 +92,7 @@ CONFIG_PARSER_PROTOTYPE(config_parse_qdisc_handle);
 #include "ets.h"
 #include "fifo.h"
 #include "fq-codel.h"
+#include "fq-pie.h"
 #include "fq.h"
 #include "gred.h"
 #include "hhf.h"

test/fuzz/fuzz-network-parser/directives.network

@@ -471,3 +471,7 @@ PriorityMap=
 Parent=
 Handle=
 PacketLimit=
+[FlowQueuePIE]
+Parent=
+Handle=
+PacketLimit=