CUDA: route batch>=4 quantized matmul to MMQ on AMD MFMA hardware

ggml/src/ggml-cuda/ggml-cuda.cu

@@ -2569,6 +2569,7 @@ static void ggml_cuda_mul_mat(ggml_backend_cuda_context & ctx, const ggml_tensor
             use_mul_mat_q           = use_mul_mat_q             && ggml_cuda_should_use_mmq(src0->type, cc, src1->ne[1], /*n_experts=*/0);
             use_mul_mat_f           = use_mul_mat_f             && ggml_cuda_should_use_mmf(src0->type, cc, warp_size, src0->ne, src0->nb, src1->ne[1], /*mul_mat_id=*/false);
             use_mul_mat_vec_f       = use_mul_mat_vec_f         && ggml_cuda_should_use_mmvf(src0->type, cc, src0->ne, src0->nb, src1->ne[1]);
+            use_mul_mat_vec_q       = use_mul_mat_vec_q         && ggml_cuda_should_use_mmvq(src0->type, cc, src1->ne[1]);
             any_gpus_with_slow_fp16 = any_gpus_with_slow_fp16   || !fast_fp16_hardware_available(cc);
         }
     } else {
@@ -2577,6 +2578,7 @@ static void ggml_cuda_mul_mat(ggml_backend_cuda_context & ctx, const ggml_tensor
         use_mul_mat_q           = use_mul_mat_q             && ggml_cuda_should_use_mmq(src0->type, cc, src1->ne[1], /*n_experts=*/0);
         use_mul_mat_f           = use_mul_mat_f             && ggml_cuda_should_use_mmf(src0->type, cc, warp_size, src0->ne, src0->nb, src1->ne[1], /*mul_mat_id=*/false);
         use_mul_mat_vec_f       = use_mul_mat_vec_f         && ggml_cuda_should_use_mmvf(src0->type, cc, src0->ne, src0->nb, src1->ne[1]);
+        use_mul_mat_vec_q       = use_mul_mat_vec_q         && ggml_cuda_should_use_mmvq(src0->type, cc, src1->ne[1]);
         any_gpus_with_slow_fp16 = any_gpus_with_slow_fp16   || !fast_fp16_hardware_available(cc);
     }
 

ggml/src/ggml-cuda/mmvq.cu

@@ -271,6 +271,53 @@ int get_mmvq_mmid_max_batch(ggml_type type, int cc) {
     return MMVQ_MAX_BATCH_SIZE;
 }
 
+bool ggml_cuda_should_use_mmvq(enum ggml_type type, int cc, int64_t ne11) {
+    if (GGML_CUDA_CC_IS_CDNA(cc)) {
+        if (GGML_CUDA_CC_IS_CDNA1(cc)) {
+            switch (type) {
+                case GGML_TYPE_Q4_0:
+                case GGML_TYPE_Q4_1:
+                    return ne11 <= 7;
+                case GGML_TYPE_Q5_1:
+                    return ne11 <= 7;
+                case GGML_TYPE_Q8_0:
+                    return ne11 <= 6;
+                case GGML_TYPE_Q2_K:
+                    return ne11 <= 4;
+                case GGML_TYPE_Q3_K:
+                    return ne11 <= 3;
+                case GGML_TYPE_Q4_K:
+                    return ne11 <= 2;
+                case GGML_TYPE_Q5_K:
+                    return ne11 <= 3;
+                case GGML_TYPE_Q6_K:
+                    return ne11 <= 4;
+                case GGML_TYPE_IQ1_S:
+                    return ne11 <= 5;
+                case GGML_TYPE_IQ2_XXS:
+                case GGML_TYPE_IQ3_S:
+                case GGML_TYPE_IQ4_XS:
+                    return ne11 <= 6;
+                default:
+                    return ne11 <= MMVQ_MAX_BATCH_SIZE;
+            }
+        }
+        switch (type) { // tuned for CDNA2
+            case GGML_TYPE_Q2_K:
+                return ne11 <= 5;
+            case GGML_TYPE_Q3_K:
+            case GGML_TYPE_Q4_K:
+            case GGML_TYPE_Q5_K:
+                return ne11 <= 3;
+            case GGML_TYPE_Q6_K:
+                return ne11 <= 5;
+            default:
+                return ne11 <= MMVQ_MAX_BATCH_SIZE;
+        }
+    }
+    return ne11 <= MMVQ_MAX_BATCH_SIZE;
+}
+
 // Device constexpr: returns the max batch size for the current arch+type at compile time.
 template <ggml_type type>
 static constexpr __device__ int get_mmvq_mmid_max_batch_for_device() {

ggml/src/ggml-cuda/mmvq.cuh

@@ -2,6 +2,8 @@
 
 #define MMVQ_MAX_BATCH_SIZE 8 // Max. batch size for which to use MMVQ kernels.
 
+bool ggml_cuda_should_use_mmvq(enum ggml_type type, int cc, int64_t ne11);
+
 // Returns the maximum batch size for which MMVQ should be used for MUL_MAT_ID,
 // based on the quantization type and GPU architecture (compute capability).
 int get_mmvq_mmid_max_batch(ggml_type type, int cc);