metal : support virtual devices (#18919)

* metal : support virtual devices

* cont : manage buffer type context memory

* metal : add events

* cont : implement cpy_tensor_async

ggml/src/ggml-metal/ggml-metal-device.m

@@ -24,9 +24,6 @@
 static const NSInteger MTLGPUFamilyMetal3_GGML = 5001;
 static const NSInteger MTLGPUFamilyMetal4_GGML = 5002;
 
-// virtual address for GPU memory allocations
-static atomic_uintptr_t g_addr_device = 0x000000400ULL;
-
 #if !GGML_METAL_EMBED_LIBRARY
 // Here to assist with NSBundle Path Hack
 @interface GGMLMetalClass : NSObject
@@ -523,6 +520,9 @@ struct ggml_metal_device {
     ggml_metal_library_t library;
 
     struct ggml_metal_device_props props;
+
+    // virtual address for GPU memory allocations
+    atomic_uintptr_t addr_virt;
 };
 
 //
@@ -618,7 +618,7 @@ void ggml_metal_rsets_free(ggml_metal_rsets_t rsets) {
     free(rsets);
 }
 
-ggml_metal_device_t ggml_metal_device_init(void) {
+ggml_metal_device_t ggml_metal_device_init(int device) {
     ggml_metal_device_t dev = calloc(1, sizeof(struct ggml_metal_device));
 
     assert(dev != NULL);
@@ -632,6 +632,9 @@ ggml_metal_device_t ggml_metal_device_init(void) {
                 GGML_LOG_ERROR("%s: error: failed to create command queue\n", __func__);
             }
 
+            dev->addr_virt = 0x000000400ULL;
+
+            dev->props.device = device;
             dev->props.has_simdgroup_reduction  = [dev->mtl_device supportsFamily:MTLGPUFamilyApple7];
             dev->props.has_simdgroup_reduction |= [dev->mtl_device supportsFamily:MTLGPUFamilyMetal3_GGML];
 
@@ -792,7 +795,8 @@ ggml_metal_device_t ggml_metal_device_init(void) {
                 dev->props.max_working_set_size   = dev->mtl_device.maxBufferLength;
             }
 
-            strncpy(dev->props.name, [[dev->mtl_device name] UTF8String], sizeof(dev->props.name) - 1);
+            snprintf(dev->props.name, sizeof(dev->props.name), "%s%d", "MTL", device);
+            snprintf(dev->props.desc, sizeof(dev->props.desc), "%s", [[dev->mtl_device name] UTF8String]);
 
             dev->library = ggml_metal_library_init(dev);
             if (!dev->library) {
@@ -922,6 +926,59 @@ void ggml_metal_device_rsets_keep_alive(ggml_metal_device_t dev) {
     atomic_store_explicit(&dev->rsets->d_loop, 2*dev->rsets->keep_alive_s, memory_order_relaxed);
 }
 
+struct ggml_metal_event {
+    void * obj; // id<MTLEvent>
+
+    atomic_int value;
+};
+
+void ggml_metal_event_encode_signal(ggml_metal_event_t ev, ggml_metal_cmd_buf_t cmd_buf_raw) {
+    id<MTLEvent> event = (id<MTLEvent>)ev->obj;
+
+    id<MTLCommandBuffer> cmd_buf = (id<MTLCommandBuffer>) cmd_buf_raw;
+
+    [cmd_buf encodeSignalEvent:event value:atomic_fetch_add_explicit(&ev->value, 1, memory_order_relaxed) + 1];
+}
+
+void ggml_metal_event_encode_wait(ggml_metal_event_t ev, ggml_metal_cmd_buf_t cmd_buf_raw) {
+    id<MTLEvent> event = (id<MTLEvent>)ev->obj;
+
+    id<MTLCommandBuffer> cmd_buf = (id<MTLCommandBuffer>) cmd_buf_raw;
+
+    [cmd_buf encodeWaitForEvent:event value:atomic_load_explicit(&ev->value, memory_order_relaxed)];
+}
+
+ggml_metal_event_t ggml_metal_device_event_init(ggml_metal_device_t dev) {
+    id<MTLEvent> event = [dev->mtl_device newEvent];
+
+    ggml_metal_event_t ev = calloc(1, sizeof(struct ggml_metal_event));
+
+    ev->obj = (__bridge void *)event;
+    ev->value = 0;
+
+    return ev;
+}
+
+void ggml_metal_device_event_free(ggml_metal_device_t dev, ggml_metal_event_t ev) {
+    id<MTLEvent> event = ev->obj;
+    [event release];
+
+    free(ev);
+
+    GGML_UNUSED(dev);
+}
+
+void ggml_metal_device_event_synchronize(ggml_metal_device_t dev, ggml_metal_event_t ev) {
+    @autoreleasepool {
+        id<MTLEvent> event = ev->obj;
+
+        id<MTLCommandBuffer> cmd_buf = [dev->mtl_queue commandBuffer];
+        [cmd_buf encodeWaitForEvent:event value:atomic_load_explicit(&ev->value, memory_order_relaxed)];
+        [cmd_buf commit];
+        [cmd_buf waitUntilCompleted];
+    }
+}
+
 void ggml_metal_device_get_memory(ggml_metal_device_t dev, size_t * free, size_t * total) {
     if (@available(macOS 10.12, iOS 16.0, *)) {
         *total = dev->mtl_device.recommendedMaxWorkingSetSize;
@@ -1344,8 +1401,8 @@ ggml_metal_buffer_t ggml_metal_buffer_init(ggml_metal_device_t dev, size_t size,
         res->all_data = ggml_metal_host_malloc(size_aligned);
         res->is_shared = true;
     } else {
-        // use virtual address from g_addr_device counter
-        res->all_data = (void *) atomic_fetch_add_explicit(&g_addr_device, size_aligned, memory_order_relaxed);
+        // use virtual address
+        res->all_data = (void *) atomic_fetch_add_explicit(&dev->addr_virt, size_aligned, memory_order_relaxed);
         res->is_shared = false;
     }
     res->all_size = size_aligned;