From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jesse Gross <jesse@ollama.com>
Date: Thu, 24 Apr 2025 14:48:51 -0700
Subject: [PATCH] ggml: Export GPU UUIDs

This enables matching up devices and information reported by the backend
with tools (e.g. nvidia-smi) and system management libraries (e.g. nvml).
---
 ggml/include/ggml-backend.h      |  1 +
 ggml/src/ggml-cuda/ggml-cuda.cu  | 39 ++++++++++++++++++++++++++++++++
 ggml/src/ggml-metal/ggml-metal.m |  1 +
 3 files changed, 41 insertions(+)

diff --git a/ggml/include/ggml-backend.h b/ggml/include/ggml-backend.h
index 74e46716..48839339 100644
--- a/ggml/include/ggml-backend.h
+++ b/ggml/include/ggml-backend.h
@@ -152,6 +152,7 @@ extern "C" {
     struct ggml_backend_dev_props {
         const char * name;
         const char * description;
+        const char * id;
         size_t memory_free;
         size_t memory_total;
         enum ggml_backend_dev_type type;
diff --git a/ggml/src/ggml-cuda/ggml-cuda.cu b/ggml/src/ggml-cuda/ggml-cuda.cu
index cb0d8528..d6960174 100644
--- a/ggml/src/ggml-cuda/ggml-cuda.cu
+++ b/ggml/src/ggml-cuda/ggml-cuda.cu
@@ -2884,6 +2884,7 @@ struct ggml_backend_cuda_device_context {
     int device;
     std::string name;
     std::string description;
+    std::string id;
 };
 
 static const char * ggml_backend_cuda_device_get_name(ggml_backend_dev_t dev) {
@@ -2896,6 +2897,11 @@ static const char * ggml_backend_cuda_device_get_description(ggml_backend_dev_t
     return ctx->description.c_str();
 }
 
+static const char * ggml_backend_cuda_device_get_id(ggml_backend_dev_t dev) {
+    ggml_backend_cuda_device_context * ctx = (ggml_backend_cuda_device_context *)dev->context;
+    return ctx->id.c_str();
+}
+
 static void ggml_backend_cuda_device_get_memory(ggml_backend_dev_t dev, size_t * free, size_t * total) {
     ggml_backend_cuda_device_context * ctx = (ggml_backend_cuda_device_context *)dev->context;
     ggml_cuda_set_device(ctx->device);
@@ -2910,6 +2916,7 @@ static enum ggml_backend_dev_type ggml_backend_cuda_device_get_type(ggml_backend
 static void ggml_backend_cuda_device_get_props(ggml_backend_dev_t dev, ggml_backend_dev_props * props) {
     props->name        = ggml_backend_cuda_device_get_name(dev);
     props->description = ggml_backend_cuda_device_get_description(dev);
+    props->id          = ggml_backend_cuda_device_get_id(dev);
     props->type        = ggml_backend_cuda_device_get_type(dev);
     ggml_backend_cuda_device_get_memory(dev, &props->memory_free, &props->memory_total);
 
@@ -3458,6 +3465,38 @@ ggml_backend_reg_t ggml_backend_cuda_reg() {
                 CUDA_CHECK(cudaGetDeviceProperties(&prop, i));
                 dev_ctx->description = prop.name;
 
+                #if !defined(GGML_USE_HIP)
+                char id[64];
+                snprintf(id, sizeof(id),
+                    "GPU-%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
+                    (unsigned char)prop.uuid.bytes[0],
+                    (unsigned char)prop.uuid.bytes[1],
+                    (unsigned char)prop.uuid.bytes[2],
+                    (unsigned char)prop.uuid.bytes[3],
+                    (unsigned char)prop.uuid.bytes[4],
+                    (unsigned char)prop.uuid.bytes[5],
+                    (unsigned char)prop.uuid.bytes[6],
+                    (unsigned char)prop.uuid.bytes[7],
+                    (unsigned char)prop.uuid.bytes[8],
+                    (unsigned char)prop.uuid.bytes[9],
+                    (unsigned char)prop.uuid.bytes[10],
+                    (unsigned char)prop.uuid.bytes[11],
+                    (unsigned char)prop.uuid.bytes[12],
+                    (unsigned char)prop.uuid.bytes[13],
+                    (unsigned char)prop.uuid.bytes[14],
+                    (unsigned char)prop.uuid.bytes[15]
+                  );
+                dev_ctx->id = id;
+                #else
+                #ifdef _WIN32
+                char id[16];
+                snprintf(id, sizeof(id), "%d", i);
+                dev_ctx->id = id;
+                #else
+                dev_ctx->id = "GPU-" + std::string(prop.uuid.bytes, 16);
+                #endif
+                #endif
+
                 ggml_backend_dev_t dev = new ggml_backend_device {
                     /* .iface   = */ ggml_backend_cuda_device_interface,
                     /* .reg     = */ &reg,
diff --git a/ggml/src/ggml-metal/ggml-metal.m b/ggml/src/ggml-metal/ggml-metal.m
index 1b56f858..a9eeebc6 100644
--- a/ggml/src/ggml-metal/ggml-metal.m
+++ b/ggml/src/ggml-metal/ggml-metal.m
@@ -5703,6 +5703,7 @@ static enum ggml_backend_dev_type ggml_backend_metal_device_get_type(ggml_backen
 static void ggml_backend_metal_device_get_props(ggml_backend_dev_t dev, struct ggml_backend_dev_props * props) {
     props->name        = ggml_backend_metal_device_get_name(dev);
     props->description = ggml_backend_metal_device_get_description(dev);
+    props->id          = "0";
     props->type        = ggml_backend_metal_device_get_type(dev);
     ggml_backend_metal_device_get_memory(dev, &props->memory_free, &props->memory_total);
     props->caps = (struct ggml_backend_dev_caps) {
