Multi GPU support, CUDA refactor, CUDA scratch buffer (#1703)

* CUDA multi GPU + scratch

ggml_cuda_compute_forward

Tensor parallelism

ggml_cuda_add

ggml_cuda_rms_norm

ggml_cuda_silu

CUDA scratch buffer

--main-gpu CLI option

1 files changed, 13 insertions, 3 deletions

diff --git a/llama.h b/llama.h
index 7a64197..dc033b7 100644
--- a/llama.h
+++ b/llama.h
@@ -1,6 +1,13 @@
 #ifndef LLAMA_H
 #define LLAMA_H
 
+#include "ggml.h"
+#ifdef GGML_USE_CUBLAS
+#include "ggml-cuda.h"
+#define LLAMA_MAX_DEVICES GGML_CUDA_MAX_DEVICES
+#else
+#define LLAMA_MAX_DEVICES 1
+#endif // GGML_USE_CUBLAS
 #include <stddef.h>
 #include <stdint.h>
 #include <stdbool.h>
@@ -65,9 +72,12 @@ extern "C" {
     typedef void (*llama_progress_callback)(float progress, void *ctx);
 
     struct llama_context_params {
-        int n_ctx;        // text context
-        int n_gpu_layers; // number of layers to store in VRAM
-        int seed;         // RNG seed, -1 for random
+        int n_ctx;                             // text context
+        int n_batch;                           // prompt processing batch size
+        int n_gpu_layers;                      // number of layers to store in VRAM
+        int main_gpu;                          // the GPU that is used for scratch and small tensors
+        float tensor_split[LLAMA_MAX_DEVICES]; // how to split layers across multiple GPUs
+        int seed;                              // RNG seed, -1 for random
 
         bool f16_kv;     // use fp16 for KV cache
         bool logits_all; // the llama_eval() call computes all logits, not just the last one