network: TC - introduce pfifo_fast

pfifo_fast - three-band first in, first out queue

Please see https://linux.die.net/man/8/tc-pfifo_fast

src/network/networkd-network-gperf.gperf

@@ -280,6 +280,8 @@ DeficitRoundRobinSchedulerClass.Quantum,     config_parse_drr_size,
 PFIFO.Parent,                                config_parse_qdisc_parent,                                QDISC_KIND_PFIFO,              0
 PFIFO.Handle,                                config_parse_qdisc_handle,                                QDISC_KIND_PFIFO,              0
 PFIFO.PacketLimit,                           config_parse_pfifo_size,                                  QDISC_KIND_PFIFO,              0
+PFIFOFast.Parent,                            config_parse_qdisc_parent,                                QDISC_KIND_PFIFO_FAST,         0
+PFIFOFast.Handle,                            config_parse_qdisc_handle,                                QDISC_KIND_PFIFO_FAST,         0
 PFIFOHeadDrop.Parent,                        config_parse_qdisc_parent,                                QDISC_KIND_PFIFO_HEAD_DROP,    0
 PFIFOHeadDrop.Handle,                        config_parse_qdisc_handle,                                QDISC_KIND_PFIFO_HEAD_DROP,    0
 PFIFOHeadDrop.PacketLimit,                   config_parse_pfifo_size,                                  QDISC_KIND_PFIFO_HEAD_DROP,    0

src/network/networkd-network.c

@@ -492,6 +492,7 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                               "DeficitRoundRobinScheduler\0"
                               "DeficitRoundRobinSchedulerClass\0"
                               "PFIFO\0"
+                              "PFIFOFast\0"
                               "PFIFOHeadDrop\0"
                               "FairQueueing\0"
                               "FairQueueingControlledDelay\0"

src/network/tc/fifo.c

@@ -176,3 +176,8 @@ const QDiscVTable pfifo_head_drop_vtable = {
        .tca_kind = "pfifo_head_drop",
        .fill_message = fifo_fill_message,
 };
+
+const QDiscVTable pfifo_fast_vtable = {
+       .object_size = sizeof(FirstInFirstOut),
+       .tca_kind = "pfifo_fast",
+};

src/network/tc/fifo.h

@@ -14,10 +14,12 @@ typedef struct FirstInFirstOut {
 DEFINE_QDISC_CAST(PFIFO, FirstInFirstOut);
 DEFINE_QDISC_CAST(BFIFO, FirstInFirstOut);
 DEFINE_QDISC_CAST(PFIFO_HEAD_DROP, FirstInFirstOut);
+DEFINE_QDISC_CAST(PFIFO_FAST, FirstInFirstOut);
 
 extern const QDiscVTable pfifo_vtable;
 extern const QDiscVTable bfifo_vtable;
 extern const QDiscVTable pfifo_head_drop_vtable;
+extern const QDiscVTable pfifo_fast_vtable;
 
 CONFIG_PARSER_PROTOTYPE(config_parse_pfifo_size);
 CONFIG_PARSER_PROTOTYPE(config_parse_bfifo_size);

src/network/tc/qdisc.c

@@ -27,6 +27,7 @@ const QDiscVTable * const qdisc_vtable[_QDISC_KIND_MAX] = {
         [QDISC_KIND_NETEM] = &netem_vtable,
         [QDISC_KIND_PIE] = &pie_vtable,
         [QDISC_KIND_PFIFO] = &pfifo_vtable,
+        [QDISC_KIND_PFIFO_FAST] = &pfifo_fast_vtable,
         [QDISC_KIND_PFIFO_HEAD_DROP] = &pfifo_head_drop_vtable,
         [QDISC_KIND_SFB] = &sfb_vtable,
         [QDISC_KIND_SFQ] = &sfq_vtable,

src/network/tc/qdisc.h

@@ -19,6 +19,7 @@ typedef enum QDiscKind {
         QDISC_KIND_HTB,
         QDISC_KIND_NETEM,
         QDISC_KIND_PFIFO,
+        QDISC_KIND_PFIFO_FAST,
         QDISC_KIND_PFIFO_HEAD_DROP,
         QDISC_KIND_PIE,
         QDISC_KIND_SFB,