Solo5: change nic interface and avoid copy

Author: alfreb

api/hw/nic.hpp

@@ -101,7 +101,8 @@ namespace hw {
 
     virtual ~Nic() {}
 
-    virtual void upstream_received_packet(uint8_t *data, int len) = 0;
+    /** Trigger a read from buffers, pusing any packets up the stack */
+    virtual void poll() = 0;
 
   protected:
     /**

api/kernel/solo5_manager.hpp

@@ -28,15 +28,15 @@
 
 class Solo5_manager {
 private:
-  using Device_registry = std::unordered_map<PCI::classcode_t, std::vector<hw::PCI_Device>>;
+  using Device_registry = std::unordered_map<PCI::classcode, std::vector<hw::PCI_Device>>;
 
 public:
-  template <PCI::classcode_t CLASS>
+  template <PCI::classcode CLASS>
   static hw::PCI_Device& device(const int n) noexcept {
     return devices_[CLASS][n];
   };
 
-  template <PCI::classcode_t CLASS>
+  template <PCI::classcode CLASS>
   static size_t num_of_devices() noexcept {
     return devices_[CLASS].size();
   }

src/drivers/solo5net.cpp

@@ -63,6 +63,8 @@ void Solo5Net::transmit(net::Packet_ptr pckt) {
     // explicitly release the data to prevent destructor being called
     net::Packet* pckt = tail.release();
     uint8_t *buf = pckt->buf();
+
+    printf("Solo5 writing packet %i bytes \n", pckt->size());
     solo5_net_write_sync(buf, pckt->size());
 
     tail = std::move(next);
@@ -87,21 +89,33 @@ Solo5Net::create_packet(int link_offset)
 }
 
 std::unique_ptr<Packet>
-Solo5Net::recv_packet(uint8_t* data, uint16_t size)
+Solo5Net::recv_packet()
 {
   auto buffer = solo5_bufstore.get_buffer();
   auto* pckt = (net::Packet*) buffer.addr;
-
+  int size = MTU_;
   new (pckt) net::Packet(0, size, MTU_, &solo5_bufstore);
   uint8_t *buf = pckt->buf();
-  memcpy(buf, data, size);
-  return net::Packet_ptr(pckt);
+  memset(buf, 0, size);
+  // Populate the packet buffer with new packet, if any
+  if (solo5_net_read_sync(buf, &size) == 0) {
+    // Adjust packet size to match received data
+    //printf("Solo5 data size: %i \n", size);
+    if (size) {
+      pckt->set_data_end(size);
+      //printf("Solo5 Packet size: %i \n", pckt->size());
+      return net::Packet_ptr(pckt);
+    }
+  }
+  printf("Solo5 didn't get data. Size: %i \n", size);
+  return nullptr;
 }
 
-void Solo5Net::upstream_received_packet(uint8_t *data, int len)
+void Solo5Net::poll()
 {
-  auto pckt_ptr = recv_packet(data, len);
-  Link::receive(std::move(pckt_ptr));
+  auto pckt_ptr = recv_packet();
+  if (pckt_ptr != nullptr)
+    Link::receive(std::move(pckt_ptr));
 }
 
 void Solo5Net::deactivate()

src/drivers/solo5net.hpp

@@ -47,9 +47,7 @@ class Solo5Net : public net::Link_layer<net::Ethernet> {
   /** Mac address. */
   const MAC::Addr& mac() const noexcept override
   {
-    char *smac = solo5_net_mac_str();
-    MAC::Addr mac(smac);
-    return mac;
+    return MAC::Addr(solo5_net_mac_str());
   }
 
   uint16_t MTU() const noexcept override
@@ -74,16 +72,19 @@ class Solo5Net : public net::Link_layer<net::Ethernet> {
     return 0;
   }
 
-  net::Packet_ptr create_packet(int);
-  void move_to_this_cpu() {};
+  net::Packet_ptr create_packet(int) override;
+
+  void move_to_this_cpu() override {};
 
   void deactivate() override;
 
-  void upstream_received_packet(uint8_t *data, int len) override;
+  void flush() override {};
+
+  void poll() override;
 
 private:
 
-  std::unique_ptr<net::Packet> recv_packet(uint8_t* data, uint16_t sz);
+  std::unique_ptr<net::Packet> recv_packet();
   /** Stats */
   uint64_t& packets_rx_;
   uint64_t& packets_tx_;

src/drivers/virtionet.hpp

@@ -166,7 +166,7 @@ class VirtioNet : Virtio, public net::Link_layer<net::Ethernet> {
 
   void move_to_this_cpu() override;
 
-  void upstream_received_packet(uint8_t *data, int len) override {}
+  void poll() {}
 
 private:
 

src/drivers/vmxnet3.hpp

@@ -78,7 +78,7 @@ class vmxnet3 : public net::Link_layer<net::Ethernet>
 
   void move_to_this_cpu() override;
 
-  void upstream_received_packet(uint8_t *data, int len) override {}
+  void poll() override {}
 
 private:
   void msix_evt_handler();

src/platform/x86_solo5/os.cpp

@@ -203,8 +203,8 @@ void OS::start(char* _cmdline, uintptr_t mem_size)
 
 void OS::event_loop()
 {
-  uint8_t *data = (uint8_t *) malloc(1520);
-  assert(data);
+  //uint8_t *data = (uint8_t *) malloc(1520);
+  //assert(data);
 
   while (power_) {
     int rc;
@@ -219,24 +219,19 @@ void OS::event_loop()
     // for the next immediate timer to fire (the first from the "scheduled" list
     // of timers?)
     rc = solo5_poll(solo5_clock_monotonic() + 500000ULL); // now + 0.5 ms
-    if (rc == 0) {
-      Timers::timers_handler();
-    } else {
-      int len = 1520;
-      memset(data, 0, 1520);
-
-      if (solo5_net_read_sync(data, &len) == 0) {
-        // XXX: packet is copied by upstream_received_packet (slow!)
-        for(auto& nic : hw::Devices::devices<hw::Nic>()) {
-          nic->upstream_received_packet(data, len);
-          break;
-        }
-      }
+    Timers::timers_handler();
+    if (rc) {
+
+      //int len = 1520;
+      //memset(data, 0, 1520);
 
+      for(auto& nic : hw::Devices::devices<hw::Nic>()) {
+        nic->poll();
+        break;
+      }
     }
   }
 
-  free(data);
 
   MYINFO("Stopping service");
   Service::stop();
@@ -300,20 +295,12 @@ void OS::block(){
   if (rc == 0) {
     Timers::timers_handler();
   } else {
-    int len = 1520;
-    uint8_t *data = (uint8_t *) malloc(1520);
-    assert(data);
-    memset(data, 0, 1520);
 
-    if (solo5_net_read_sync(data, &len) == 0) {
-      // make sure packet is copied
-      for(auto& nic : hw::Devices::devices<hw::Nic>()) {
-        nic->upstream_received_packet(data, len);
-        break;
-      }
+    for(auto& nic : hw::Devices::devices<hw::Nic>()) {
+      nic->poll();
+      break;
     }
 
-    free(data);
   }
 
   // Decrement level

src/platform/x86_solo5/platform.cpp

@@ -30,3 +30,5 @@ void SMP::global_lock() noexcept {}
 void SMP::global_unlock() noexcept {}
 int SMP::cpu_id() noexcept { return 0; }
 int SMP::cpu_count() noexcept { return 1; }
+void SMP::signal(int) { }
+void SMP::add_task(SMP::task_func, int) { };

src/platform/x86_solo5/start.asm

@@ -18,7 +18,6 @@
 global __multiboot_magic
 global __multiboot_addr
 global set_stack
-global get_cpu_ebp
 
 %define  MB_MAGIC   0x1BADB002
 %define  MB_FLAGS   0x3  ;; ALIGN + MEMINFO
@@ -49,7 +48,3 @@ set_stack:
   mov esp, 0xA0000
   mov ebp, esp
   call kernel_start
-
-get_cpu_ebp:
-    mov eax, ebp
-    ret