Update virtio-loopback adapter - Add priority featureHEADmaster

Add scheduling mechanism for virtio interrupts and
messages. This mechanism can be used to prioritize
one virtio-device's requests over the other by
setting the args "credits=" and "priority=" into
the adapter's arguments.

Change-Id: Id322c21b87b41317153b649191d9e7e66d2fb317
Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>

5 files changed, 72 insertions, 10 deletions

diff --git a/include/vhost_user_loopback.h b/include/vhost_user_loopback.h
index 8b0294f..25f9a25 100644
--- a/include/vhost_user_loopback.h
+++ b/include/vhost_user_loopback.h
@@ -239,6 +239,9 @@ typedef struct Device {
     int device_index;
     int requires_socket;
     int client_socket;
+    bool priority_enabled;
+    int credits;
+    int priority_group;
 } Device;
 
 typedef struct adapter_dev {
diff --git a/include/virtio_loopback.h b/include/virtio_loopback.h
index e3f4a78..878bd4f 100644
--- a/include/virtio_loopback.h
+++ b/include/virtio_loopback.h
@@ -493,10 +493,11 @@ typedef struct virtio_device_info_struct {
     unsigned long version;
     unsigned long device_id;
     unsigned long vendor;
-
+    bool priority_enabled;      
+    unsigned long credits;
+    unsigned long priority_group;
 } virtio_device_info_struct_t;
 
-
 /* Negotiation structs */
 
 typedef struct { int counter; } atomic_t;
diff --git a/src/adapter/adapter.c b/src/adapter/adapter.c
index 55de251..3d65ce3 100644
--- a/src/adapter/adapter.c
+++ b/src/adapter/adapter.c
@@ -123,7 +123,7 @@ static void client(Device *device)
     len = sizeof(client_sockaddr);
     rc = connect(device->client_socket, (struct sockaddr *) &client_sockaddr, len);
     if (rc == -1) {
-        printf("CONNECT ERROR: Check the \"-s\" parameter\n");
+        printf("CONNECT ERROR: Check the \"socket\" parameter: %s\n", sock_path);
         close(device->client_socket);
         exit(1);
     }
diff --git a/src/adapter/parser.c b/src/adapter/parser.c
index 0300baa..2a3914a 100644
--- a/src/adapter/parser.c
+++ b/src/adapter/parser.c
@@ -70,6 +70,24 @@ static int check_queue_size(const char *queue_size_str) {
     return (queue_size > 0) && ((queue_size & (queue_size - 1)) == 0);
 }
 
+static int check_credits(const char *credits_str) {
+    if (!is_number(credits_str)) {
+        return 0;
+    }
+    int credits = atoi(credits_str);
+    // Check if the queue_size is a power of 2
+    return (credits > 0);
+}
+
+static int check_priority(const char *priority_str) {
+    if (!is_number(priority_str)) {
+        return 0;
+    }
+    int priority = atoi(priority_str);
+    // Check if the queue_size is a power of 2
+    return (priority > 0);
+}
+
 // Function to check if the socket path is valid
 static int check_socket(const char *socket_path) {
     if (socket_path == NULL || strlen(socket_path) == 0) {
@@ -93,6 +111,7 @@ static int check_socket(const char *socket_path) {
 
 // Function to check if the device name is valid and get its index
 static int check_device_name(const char *device_name, int *device_index, int *requires_socket) {
+
     for (unsigned int i = 0; i < num_adapter_devices; i++) {
         if (strcmp(device_name, adapter_devices[i]) == 0) {
             *device_index = i;
@@ -101,7 +120,7 @@ static int check_device_name(const char *device_name, int *device_index, int *re
             for (unsigned int j = 0; j < num_vhu_devices; j++) {
                 if (strcmp(device_name, vhu_devices[j]) == 0) {
                     *requires_socket = 1;
-                    break;
+                    return 1;
                 }
             }
             return 1;  // Valid device name
@@ -112,11 +131,15 @@ static int check_device_name(const char *device_name, int *device_index, int *re
 
 static int parse_device_arg(const char *arg, Device *device) {
 
-	char *token;
+    char *token;
+    bool socket_provided = false;
 
     // Initialize with default values
     device->queue_num = DEFAULT_QUEUE_NUM;
     device->queue_size = DEFAULT_QUEUE_SIZE;
+    device->credits = 10;
+    device->priority_enabled = false;
+    device->priority_group = 1;
 
     // Extract device name
     token = strtok((char *)arg, ",");
@@ -126,6 +149,7 @@ static int parse_device_arg(const char *arg, Device *device) {
 
     // Check if the device name is valid and get the index and socket requirement
     if (!check_device_name(token, &device->device_index, &device->requires_socket)) {
+	printf("no device recognised\n");
         return -1;  // Invalid device name
     }
     strncpy(device->device_name, token, MAX_NAME_LENGTH - 1);
@@ -137,10 +161,12 @@ static int parse_device_arg(const char *arg, Device *device) {
             const char *socket_path = token + 7; // Skip "socket="
             if (device->requires_socket) {
                 if (!check_socket(socket_path)) {
+                    fprintf(stderr, "Error: Socket path: %s is invalid\n", socket_path);
                     return -1;  // Invalid socket path
                 }
                 strncpy(device->socket, socket_path, MAX_SOCKET_LENGTH - 1);
                 device->socket[MAX_SOCKET_LENGTH - 1] = '\0';  // Ensure null termination
+                socket_provided = true;
             } else {
                 // If device does not allow socket, return an error
                 fprintf(stderr, "Error: Socket path is not allowed for device: %s\n", device->device_name);
@@ -158,17 +184,43 @@ static int parse_device_arg(const char *arg, Device *device) {
                 return -1;  // Invalid queue_size
             }
             device->queue_size = atoi(queue_size_str); // Skip "queue_size="
+        } else if (strncmp(token, "credits=", 8) == 0) {
+            const char *credits_str = token + 8;
+            if (!check_credits(credits_str)) {
+                return -1;  // Invalid queue_size
+            }
+            device->credits = atoi(credits_str);
+            device->priority_enabled = true;
+        } else if (strncmp(token, "priority=", 9) == 0) {
+            const char *priority_str = token + 9;
+            if (!check_priority(priority_str)) {
+                return -1;  // Invalid queue_size
+            }
+            device->priority_group = atoi(priority_str);
+            device->priority_enabled = true;
         } else {
+            printf("Error: there is no argument: \"%s\"\n", token);
             return -1;  // Unknown parameter
         }
     }
 
+    /* Overall check */
+    if (device->requires_socket & !socket_provided) {
+        printf("No socket is provided\n");
+        return -1;
+    }
+
     return 0;
 }
 
 int parse_args(int argc, char *argv[]) {
     int device_count = 0;
 
+    if (argc == 0) {
+        printf("No device available\n");
+	return -1;
+    }
+
     // Iterate over the command line arguments
     for (int i = 1; i < argc; i++) {
         if (strcmp(argv[i], "-device") == 0) {
@@ -176,19 +228,17 @@ int parse_args(int argc, char *argv[]) {
                 if (parse_device_arg(argv[i + 1], &devices[device_count]) == 0) {
                     device_count++;
                 } else {
-                    fprintf(stderr, "Error: Failed to parse device argument: %s\n", argv[i + 1]);
-                    return EXIT_FAILURE;
+                    return -1;
                 }
                 i++; // Skip next argument as it's already processed
             } else {
                 fprintf(stderr, "Error: Missing or too many device arguments.\n");
-                return EXIT_FAILURE;
+                return -1;
             }
         }
     }
 
-    // Output parsed devices
-    printf("Parsed %d devices:\n", device_count);
+    // If everything parsed syccessfully, uutput parsed devices
     for (int i = 0; i < device_count; i++) {
         printf("Device %d:\n", i + 1);
         printf("  Device index: %d\n", devices[i].device_index);
@@ -196,6 +246,11 @@ int parse_args(int argc, char *argv[]) {
         printf("  Socket: %s\n", devices[i].socket);
         printf("  Queue Num: %d\n", devices[i].queue_num);
         printf("  Queue Size: %d\n", devices[i].queue_size);
+        printf("  Priority: %d\n", devices[i].priority_enabled);
+	if (devices[i].priority_enabled) {
+            printf("      Credits: %d\n", devices[i].credits);
+            printf("      Group: %d\n", devices[i].priority_group);
+	}
     }
 
     return device_count;
diff --git a/src/lib/virtio_loopback.c b/src/lib/virtio_loopback.c
index 6f84bc3..9016188 100644
--- a/src/lib/virtio_loopback.c
+++ b/src/lib/virtio_loopback.c
@@ -1107,6 +1107,9 @@ void virtio_dev_init(VirtIODevice *vdev, const char *name,
     adev->device_info.version = 0x1;
     adev->device_info.device_id = device_id;
     adev->device_info.vendor = 0x554d4551;
+    adev->device_info.priority_enabled = adev->device_params->priority_enabled;
+    adev->device_info.credits = (unsigned long)adev->device_params->credits;
+    adev->device_info.priority_group = (unsigned long)adev->device_params->priority_group;
 
     vdev->use_guest_notifier_mask = true;
 }