resource: Move vector of queues into io_queue_topology

The io_queue_topology describes "numerical" topology -- the
numbers of queues and groups and their mappings to each other.
Later this info is materialized into device_io_topology by
creating vectors of queues and groups.

There's no real need in this split. The io_queue_topology can
just create the needed vectors with no objects in them, so
that later queues and groups are put into _it_ instead of on
the device_io_topology.

This is step scylladb#1 -- move vector of queues into io_queue_topology.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>

include/seastar/core/resource.hh

@@ -64,7 +64,7 @@ struct memory {
 // This will allow us to easily find who is the IO coordinator for a given
 // node without a trip to a remote CPU.
 struct io_queue_topology {
-    unsigned nr_queues;
+    std::vector<io_queue*> queues;
     std::vector<unsigned> shard_to_group;
     unsigned nr_groups;
 
@@ -85,7 +85,6 @@ struct resources {
 };
 
 struct device_io_topology {
-    std::vector<io_queue*> queues;
     struct group {
         std::shared_ptr<io_group> g;
         unsigned attached = 0;
@@ -94,7 +93,7 @@ struct device_io_topology {
     std::vector<group> groups;
 
     device_io_topology() noexcept = default;
-    device_io_topology(const io_queue_topology& iot) noexcept : queues(iot.nr_queues), groups(iot.nr_groups) {}
+    device_io_topology(const io_queue_topology& iot) noexcept : groups(iot.nr_groups) {}
 };
 
 resources allocate(configuration c);

src/core/reactor.cc

@@ -3917,12 +3917,12 @@ void smp::configure(boost::program_options::variables_map configuration, reactor
             group = iog.g;
         }
 
-        topology.queues[shard] = new io_queue(std::move(group), engine()._io_sink);
+        io_info.queues[shard] = new io_queue(std::move(group), engine()._io_sink);
         seastar_logger.debug("attached {} queue to {} IO group", shard, group_idx);
     };
 
-    auto assign_io_queue = [&devices_topology] (shard_id shard_id, dev_t dev_id) {
-        io_queue* queue = devices_topology[dev_id].queues[shard_id];
+    auto assign_io_queue = [&ioq_topology] (shard_id shard_id, dev_t dev_id) {
+        io_queue* queue = ioq_topology[dev_id].queues[shard_id];
         engine()._io_queues.emplace(dev_id, queue);
     };
 

src/core/resource.cc

@@ -31,6 +31,7 @@
 #include <limits>
 #include "cgroup.hh"
 #include <seastar/util/log.hh>
+#include <seastar/core/io_queue.hh>
 
 #include <boost/range/adaptor/map.hpp>
 #include <boost/range/algorithm/copy.hpp>
@@ -249,7 +250,7 @@ io_queue_topology::~io_queue_topology() {
 }
 
 io_queue_topology::io_queue_topology(io_queue_topology&& o)
-    : nr_queues(std::exchange(o.nr_queues, 0))
+    : queues(std::move(o.queues))
     , shard_to_group(std::move(o.shard_to_group))
     , nr_groups(std::exchange(o.nr_groups, 0))
 { }
@@ -412,7 +413,7 @@ allocate_io_queues(hwloc_topology_t& topology, std::vector<cpu> cpus, std::unord
     };
 
     auto cpu_sets = distribute_objects(topology, num_io_groups);
-    ret.nr_queues = cpus.size();
+    ret.queues.resize(cpus.size());
     ret.nr_groups = 0;
 
     // First step: distribute the IO queues given the information returned in cpu_sets.
@@ -639,7 +640,7 @@ allocate_io_queues(configuration c, std::vector<cpu> cpus) {
     io_queue_topology ret;
 
     unsigned nr_cpus = unsigned(cpus.size());
-    ret.nr_queues = nr_cpus;
+    ret.queues.resize(nr_cpus);
     ret.shard_to_group.resize(nr_cpus);
     ret.nr_groups = 1;