ggml: new backend for Virglrenderer API Remoting acceleration (v2) (#18718)

ggml/src/ggml-virtgpu/ggml-backend-reg.cpp

@@ -0,0 +1,137 @@
+#include "ggml-remoting.h"
+#include "ggml-virtgpu.h"
+
+#include <iostream>
+#include <mutex>
+
+static virtgpu * apir_initialize() {
+    static virtgpu * apir_gpu_instance = NULL;
+    static bool      apir_initialized  = false;
+
+    {
+        static std::mutex           mutex;
+        std::lock_guard<std::mutex> lock(mutex);
+
+        if (apir_initialized) {
+            return apir_gpu_instance;
+        }
+
+        apir_gpu_instance = create_virtgpu();
+        if (!apir_gpu_instance) {
+            GGML_ABORT("failed to initialize the virtgpu");
+        }
+
+        apir_initialized = true;
+    }
+
+    return apir_gpu_instance;
+}
+
+static int ggml_backend_remoting_get_device_count() {
+    virtgpu * gpu = apir_initialize();
+    if (!gpu) {
+        GGML_LOG_WARN("apir_initialize failed\n");
+        return 0;
+    }
+
+    return apir_device_get_count(gpu);
+}
+
+static size_t ggml_backend_remoting_reg_get_device_count(ggml_backend_reg_t reg) {
+    UNUSED(reg);
+
+    return ggml_backend_remoting_get_device_count();
+}
+
+static std::vector<ggml_backend_dev_t> devices;
+
+ggml_backend_dev_t ggml_backend_remoting_get_device(size_t device) {
+    GGML_ASSERT(device < devices.size());
+    return devices[device];
+}
+
+static void ggml_backend_remoting_reg_init_devices(ggml_backend_reg_t reg) {
+    if (devices.size() > 0) {
+        GGML_LOG_INFO("%s: already initialized\n", __func__);
+        return;
+    }
+
+    virtgpu * gpu = apir_initialize();
+    if (!gpu) {
+        GGML_LOG_ERROR("apir_initialize failed\n");
+        return;
+    }
+
+    static bool initialized = false;
+
+    {
+        static std::mutex           mutex;
+        std::lock_guard<std::mutex> lock(mutex);
+        if (!initialized) {
+            for (int i = 0; i < ggml_backend_remoting_get_device_count(); i++) {
+                ggml_backend_remoting_device_context * ctx       = new ggml_backend_remoting_device_context;
+                char                                   desc[256] = "API Remoting device";
+
+                ctx->device      = i;
+                ctx->name        = GGML_REMOTING_FRONTEND_NAME + std::to_string(i);
+                ctx->description = desc;
+                ctx->gpu         = gpu;
+
+                ggml_backend_dev_t dev = new ggml_backend_device{
+                    /* .iface   = */ ggml_backend_remoting_device_interface,
+                    /* .reg     = */ reg,
+                    /* .context = */ ctx,
+                };
+                devices.push_back(dev);
+            }
+            initialized = true;
+        }
+    }
+}
+
+static ggml_backend_dev_t ggml_backend_remoting_reg_get_device(ggml_backend_reg_t reg, size_t device) {
+    UNUSED(reg);
+
+    return ggml_backend_remoting_get_device(device);
+}
+
+static const char * ggml_backend_remoting_reg_get_name(ggml_backend_reg_t reg) {
+    UNUSED(reg);
+
+    return GGML_REMOTING_FRONTEND_NAME;
+}
+
+static const ggml_backend_reg_i ggml_backend_remoting_reg_i = {
+    /* .get_name         = */ ggml_backend_remoting_reg_get_name,
+    /* .get_device_count = */ ggml_backend_remoting_reg_get_device_count,
+    /* .get_device       = */ ggml_backend_remoting_reg_get_device,
+    /* .get_proc_address = */ NULL,
+};
+
+ggml_backend_reg_t ggml_backend_virtgpu_reg() {
+    virtgpu * gpu = apir_initialize();
+    if (!gpu) {
+        GGML_LOG_ERROR("virtgpu_apir_initialize failed\n");
+        return NULL;
+    }
+
+    static ggml_backend_reg reg = {
+        /* .api_version = */ GGML_BACKEND_API_VERSION,
+        /* .iface       = */ ggml_backend_remoting_reg_i,
+        /* .context     = */ gpu,
+    };
+
+    static bool initialized = false;
+    if (initialized) {
+        return &reg;
+    }
+    initialized = true;
+
+    ggml_backend_remoting_reg_init_devices(&reg);
+
+    GGML_LOG_INFO("%s: initialized\n", __func__);
+
+    return &reg;
+}
+
+GGML_BACKEND_DL_IMPL(ggml_backend_virtgpu_reg)