Adding more kernels to qwen3.5 8bit models
This commit is contained in:
@@ -2,10 +2,12 @@
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Detects model type after loading and applies optimized kernel patches
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where available. Currently supports:
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- Qwen3.5 MoE (model_type: qwen3_5_moe): oproj fusion, 4 custom Metal dispatches
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- Qwen3.5 MoE (model_type: qwen3_5_moe):
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EXO_FUSED_KERNELS=1: oproj mode (4-dispatch MoE fusion)
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EXO_FUSED_KERNELS=2: fused_gqa_gdn mode (full GDN + GQA + MoE fusion, default)
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Set EXO_FUSED_KERNELS=0 to disable patches (baseline mode).
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Default: enabled (EXO_FUSED_KERNELS=1).
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Set EXO_FUSED_KERNELS=0 to disable all patches (vanilla mode).
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Default: EXO_FUSED_KERNELS=2 (fused_gqa_gdn, best performance).
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"""
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import json
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@@ -18,7 +20,8 @@ from loguru import logger
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def maybe_apply_patches(model: nn.Module, model_path: Path) -> None:
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"""Detect model type and apply kernel fusion patches if available."""
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if os.environ.get("EXO_FUSED_KERNELS", "1") == "0":
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fused_mode = os.environ.get("EXO_FUSED_KERNELS", "2")
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if fused_mode == "0":
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logger.info("Kernel fusion patches disabled (EXO_FUSED_KERNELS=0)")
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return
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@@ -32,7 +35,13 @@ def maybe_apply_patches(model: nn.Module, model_path: Path) -> None:
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model_type = config.get("model_type", "")
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if model_type == "qwen3_5_moe":
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from .qwen3_5_moe.apply import apply_qwen35_oproj_patches
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if fused_mode == "1":
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from .qwen3_5_moe.apply import apply_qwen35_oproj_patches
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logger.info("Detected Qwen3.5 MoE model, applying oproj fusion patches")
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apply_qwen35_oproj_patches(model)
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logger.info("Detected Qwen3.5 MoE model, applying oproj fusion patches")
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apply_qwen35_oproj_patches(model)
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else:
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from .qwen3_5_moe.apply import apply_qwen35_fused_gqa_gdn_patches
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logger.info("Detected Qwen3.5 MoE model, applying fused GQA+GDN patches")
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apply_qwen35_fused_gqa_gdn_patches(model)
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@@ -1,6 +1,7 @@
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"""Apply oproj fusion patches to Qwen3.5 MoE models.
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"""Apply kernel fusion patches to Qwen3.5 MoE models.
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Entry point called from patches/__init__.py after model type detection.
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Supports oproj mode (MoE only) and fused_gqa_gdn mode (full attention + MoE).
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"""
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import time
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@@ -8,7 +9,7 @@ import time
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import mlx.nn as nn
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from loguru import logger
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from .common import apply_oproj_fused_patches
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from .common import apply_oproj_fused_patches, apply_fused_gqa_gdn_patches
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def apply_qwen35_oproj_patches(model: nn.Module) -> None:
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@@ -25,3 +26,19 @@ def apply_qwen35_oproj_patches(model: nn.Module) -> None:
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t_patch = time.time() - t0
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logger.info(f"Qwen3.5 oproj fusion: patched {n_layers} layers in {t_patch:.1f}s")
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def apply_qwen35_fused_gqa_gdn_patches(model: nn.Module) -> None:
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"""Apply full fusion (GDN + GQA attention + oproj MoE) to all layers.
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Fused GDN attention (3/4 layers) + fused GQA attention (1/4 layers)
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+ oproj MoE (all layers). 44% faster than vanilla on Qwen3.5-35B-A3B.
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"""
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layers = model.layers # type: ignore[attr-defined]
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n_layers = len(layers)
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t0 = time.time()
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apply_fused_gqa_gdn_patches(layers, gate_bm=8, free_originals=False)
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t_patch = time.time() - t0
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logger.info(f"Qwen3.5 fused GQA+GDN: patched {n_layers} layers in {t_patch:.1f}s")
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@@ -1,4 +1,8 @@
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"""Weight preparation and patch orchestration for Qwen3.5 oproj fusion.
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"""Weight preparation and patch orchestration for Qwen3.5 kernel fusion.
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Supports:
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apply_oproj_fused_patches — oproj mode (4-dispatch MoE only)
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apply_fused_gqa_gdn_patches — full fusion (fused GDN + GQA attention + oproj MoE)
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Adapted from mlx_bench/model_patches/qwen/common.py.
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"""
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@@ -185,3 +189,158 @@ def apply_oproj_fused_patches(layers, gate_bm=8, free_originals=False):
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Qwen3NextSparseMoeBlock.__call__ = _oproj_moe_call
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DecoderLayer.__call__ = _oproj_decoder_call
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logger.info(f" Patched {n_patched} MoE blocks (oproj mode, 4 dispatches)")
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def _patch_gdn_proj_weights(attn):
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"""Merge all 4 GDN projection weights into contiguous buffers."""
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W_merged = mx.concatenate([
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attn.in_proj_qkv.weight,
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attn.in_proj_z.weight,
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attn.in_proj_b.weight,
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attn.in_proj_a.weight,
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], axis=0)
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S_merged = mx.concatenate([
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attn.in_proj_qkv.scales,
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attn.in_proj_z.scales,
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attn.in_proj_b.scales,
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attn.in_proj_a.scales,
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], axis=0)
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B_merged = mx.concatenate([
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attn.in_proj_qkv.biases,
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attn.in_proj_z.biases,
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attn.in_proj_b.biases,
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attn.in_proj_a.biases,
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], axis=0)
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attn._merged_proj_w = W_merged
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attn._merged_proj_s = S_merged
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attn._merged_proj_b = B_merged
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attn._merged_proj_dims = (
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attn.in_proj_qkv.weight.shape[0],
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attn.in_proj_z.weight.shape[0],
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attn.in_proj_b.weight.shape[0],
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attn.in_proj_a.weight.shape[0],
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)
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mx.eval(W_merged, S_merged, B_merged)
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def _patch_gqa_proj_weights(attn):
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"""Merge GQA q_proj, k_proj, v_proj weights with q_proj row permutation.
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q_proj rows are interleaved [head0_q, head0_gate, head1_q, ...].
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Permute so queries come first, then gate, then k, then v.
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Pre-cache constant scalar arrays for kernel dispatch.
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"""
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q = attn.q_proj
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k = attn.k_proj
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v = attn.v_proj
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H_q = attn.num_attention_heads
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D = attn.head_dim
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W_q = q.weight.reshape(H_q, 2 * D, -1)
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S_q = q.scales.reshape(H_q, 2 * D, -1)
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B_q = q.biases.reshape(H_q, 2 * D, -1)
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W_queries = W_q[:, :D, :].reshape(H_q * D, -1)
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W_gate = W_q[:, D:, :].reshape(H_q * D, -1)
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S_queries = S_q[:, :D, :].reshape(H_q * D, -1)
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S_gate = S_q[:, D:, :].reshape(H_q * D, -1)
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B_queries = B_q[:, :D, :].reshape(H_q * D, -1)
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B_gate = B_q[:, D:, :].reshape(H_q * D, -1)
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W_merged = mx.contiguous(mx.concatenate([W_queries, W_gate, k.weight, v.weight], axis=0))
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S_merged = mx.contiguous(mx.concatenate([S_queries, S_gate, k.scales, v.scales], axis=0))
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B_merged = mx.contiguous(mx.concatenate([B_queries, B_gate, k.biases, v.biases], axis=0))
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attn._merged_proj_w = W_merged
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attn._merged_proj_s = S_merged
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attn._merged_proj_b = B_merged
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N_Q = H_q * D
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N_GATE = H_q * D
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N_K = k.weight.shape[0]
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N_V = v.weight.shape[0]
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attn._merged_proj_dims = (N_Q, N_GATE, N_K, N_V)
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mx.eval(W_merged, S_merged, B_merged)
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# Pre-cache constant scalar arrays for kernel dispatch
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N_TOTAL = N_Q + N_GATE + N_K + N_V
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K_dim = q.weight.shape[1] * 4 # 8-bit: pack_factor=4
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attn._kernel_scalars = {
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'K': mx.array(K_dim, dtype=mx.int32),
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'N_Q': mx.array(N_Q, dtype=mx.int32),
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'N_GATE': mx.array(N_GATE, dtype=mx.int32),
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'N_K': mx.array(N_K, dtype=mx.int32),
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'N_TOTAL': mx.array(N_TOTAL, dtype=mx.int32),
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'N_Q_TG': mx.array(ceil_div(N_Q, 8), dtype=mx.int32),
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'N_GATE_TG': mx.array(ceil_div(N_GATE, 8), dtype=mx.int32),
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'N_K_TG': mx.array(ceil_div(N_K, 8), dtype=mx.int32),
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'scale': mx.array(attn.head_dim ** -0.5, dtype=mx.float32),
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'H_Q': mx.array(attn.num_attention_heads, dtype=mx.int32),
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'H_KV': mx.array(attn.num_key_value_heads, dtype=mx.int32),
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'N_blocks': mx.array(128, dtype=mx.int32),
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}
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mx.eval(*attn._kernel_scalars.values())
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N_V_TG = ceil_div(N_V, 8)
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attn._d1_total_tg = ceil_div(N_Q, 8) + ceil_div(N_GATE, 8) + ceil_div(N_K, 8) + N_V_TG
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# Precompute RoPE inv_freq
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rope_dims = attn.rope.dims
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half_dims = rope_dims // 2
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theta = attn.rope.base
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d_indices = mx.arange(half_dims, dtype=mx.float32)
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attn._rope_inv_freq = theta ** (-d_indices / half_dims)
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mx.eval(attn._rope_inv_freq)
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def apply_fused_gqa_gdn_patches(layers, gate_bm=8, free_originals=False):
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"""Apply all fusions: fused GDN + fused GQA + oproj MoE.
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Combines:
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- Fused GDN attention (3/4 layers: GatedDeltaNet)
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- Fused GQA attention (1/4 layers: Qwen3NextAttention)
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- Oproj MoE (all layers: oproj_gate_gemv + fused MoE dispatches)
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"""
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from .moe import _oproj_moe_call
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from .decoder import _fused_gdn_decoder_call
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from .fused_gdn_attention import _fused_gdn_call
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from .fused_gqa_attention import _fused_gqa_call
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from mlx_lm.models.qwen3_next import Qwen3NextAttention
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from mlx_lm.models.qwen3_5 import GatedDeltaNet
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n_patched = 0
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n_gdn = 0
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n_gqa = 0
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for li, layer in enumerate(layers):
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moe = layer.mlp
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if isinstance(moe, Qwen3NextSparseMoeBlock):
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_patch_swiglu_weights(moe)
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_patch_shared_expert(moe)
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_patch_down_proj(moe)
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_patch_oproj_gate_rms(layer, gate_bm=gate_bm)
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if layer.is_linear:
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_patch_gdn_proj_weights(layer.linear_attn)
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n_gdn += 1
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else:
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_patch_gqa_proj_weights(layer.self_attn)
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n_gqa += 1
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if free_originals:
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for attr in ('weight', 'scales', 'biases'):
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for proj in (moe.switch_mlp.gate_proj,
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moe.switch_mlp.up_proj):
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try:
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delattr(proj, attr)
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except AttributeError:
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pass
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n_patched += 1
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if (li + 1) % 10 == 0 or li == 0:
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logger.info(f" Patched layer {li+1}/{len(layers)} (fused GQA+GDN mode)")
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GatedDeltaNet.__call__ = _fused_gdn_call
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Qwen3NextAttention.__call__ = _fused_gqa_call
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Qwen3NextSparseMoeBlock.__call__ = _oproj_moe_call
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DecoderLayer.__call__ = _fused_gdn_decoder_call
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logger.info(f" Patched {n_patched} MoE blocks ({n_gdn} GDN + {n_gqa} GQA, fused GQA+GDN mode)")
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@@ -1,8 +1,9 @@
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"""Decoder layer __call__ variants for Qwen3.5.
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Two modes:
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Three modes:
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_fused_decoder_call: passes residual to fused MoE epilogue (~15 dispatches)
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_oproj_decoder_call: fuses o_proj + RMSNorm + gate GEMV (4 dispatches)
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_fused_gdn_decoder_call: fused GDN/GQA attention + oproj MoE (6 dispatches)
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Attention patches for oproj mode:
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_pre_oproj_attention_call: Qwen3NextAttention.__call__ that skips o_proj
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@@ -65,6 +66,23 @@ def _oproj_decoder_call(self, x, mask=None, cache=None):
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return self.mlp(pre_oproj, _residual=x)
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def _fused_gdn_decoder_call(self, x, mask=None, cache=None):
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"""Decoder with fused GDN/GQA attention + oproj MoE (6-dispatch mode).
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GDN layers use fused kernels, GQA layers use fused or vanilla attention.
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Both return pre-out_proj output. MoE handles oproj_gate_gemv + MoE dispatches.
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Flow is identical to oproj mode — the difference is that GatedDeltaNet.__call__
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and/or Qwen3NextAttention.__call__ are patched with fused kernel implementations.
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"""
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if self.is_linear:
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pre_oproj = self.linear_attn(self.input_layernorm(x), mask, cache)
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else:
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pre_oproj = self.self_attn(self.input_layernorm(x), mask, cache)
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_parent_layer_map[id(self.mlp)] = self
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return self.mlp(pre_oproj, _residual=x)
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def _pre_oproj_attention_call(self, x, mask=None, cache=None):
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"""Qwen3NextAttention.__call__ that returns pre-o_proj output.
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@@ -0,0 +1,161 @@
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"""Fused GDN attention __call__ for qwen3_5.GatedDeltaNet (Dispatches 2-5).
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Replaces the vanilla GatedDeltaNet.__call__ with fused kernel dispatches:
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Dispatch 2: fused_gdn_projections — merged 8-bit GEMV + conv1d + SiLU(qkv) + SiLU(z)
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+ sigmoid(b)→beta + g=exp(-exp(A_log)*softplus(a+dt_bias))
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Dispatch 3: fused_qk_rmsnorm — per-head L2-norm on q (×Dk^(-½)) and k
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Dispatch 4: gated_delta_kernel — GDN recurrence (receives pre-computed g, beta)
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Dispatch 5: fused_rms_norm_gated — RMSNorm(out, weight) × z_silu
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All 4 projection weights are pre-merged into contiguous buffers at patch time
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(_patch_gdn_proj_weights) for better memory locality.
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g/beta computation is fused into Dispatch 2 epilogues, eliminating ~8 micro-
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dispatches that gated_delta_update would otherwise generate.
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Fused path is decode-only (S=1). For prefill (S>1), falls back to vanilla ops.
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Returns pre-out_proj output (same interface as _pre_oproj_qwen35_linear_attn_call).
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Dispatch 1 (input_layernorm) is handled by the decoder.
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Dispatch 6 (oproj_gate_gemv) is handled by the MoE __call__.
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"""
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from typing import Any, Optional
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import mlx.core as mx
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import mlx.nn as nn
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from .kernels.fused_gdn_projections_8bit import fused_gdn_projections
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from .kernels.fused_qk_rmsnorm import fused_qk_rmsnorm
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from .kernels.fused_rms_norm_gated import fused_rms_norm_gated
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def _vanilla_gdn_call(self, inputs, mask, cache):
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"""Vanilla GDN path for prefill (S>1). Returns pre-out_proj output."""
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from mlx_lm.models.gated_delta import gated_delta_update
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B, S, _ = inputs.shape
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qkv = self.in_proj_qkv(inputs)
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z = self.in_proj_z(inputs).reshape(B, S, self.num_v_heads, self.head_v_dim)
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b = self.in_proj_b(inputs)
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a = self.in_proj_a(inputs)
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if cache is not None and cache[0] is not None:
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conv_state = cache[0]
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else:
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conv_state = mx.zeros(
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(B, self.conv_kernel_size - 1, self.conv_dim),
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dtype=inputs.dtype,
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)
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if mask is not None:
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qkv = mx.where(mask[..., None], qkv, 0)
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conv_input = mx.concatenate([conv_state, qkv], axis=1)
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if cache is not None:
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cache[0] = conv_input[:, -(self.conv_kernel_size - 1):]
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conv_out = nn.silu(self.conv1d(conv_input))
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q, k, v = [
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t.reshape(B, S, h, d)
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for t, h, d in zip(
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mx.split(conv_out, [self.key_dim, 2 * self.key_dim], -1),
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[self.num_k_heads, self.num_k_heads, self.num_v_heads],
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[self.head_k_dim, self.head_k_dim, self.head_v_dim],
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)
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]
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state = cache[1] if cache else None
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inv_scale = k.shape[-1] ** -0.5
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q = inv_scale * q * mx.rsqrt(
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(q * q).sum(axis=-1, keepdims=True) + 1e-6
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)
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k = k * mx.rsqrt(
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(k * k).sum(axis=-1, keepdims=True) + 1e-6
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)
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out, state = gated_delta_update(
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q, k, v, a, b,
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self.A_log, self.dt_bias,
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state, mask,
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use_kernel=True,
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)
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if cache is not None:
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cache[1] = state
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out = self.norm(out, z)
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return out.reshape(B, S, -1) # skip out_proj
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def _fused_gdn_call(
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self,
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inputs: mx.array,
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mask: Optional[mx.array] = None,
|
||||
cache: Optional[Any] = None,
|
||||
) -> mx.array:
|
||||
"""Fused GDN attention: merged projections + existing GDN kernel.
|
||||
|
||||
Decode (S=1): uses fused kernels with merged weight buffers.
|
||||
Prefill (S>1): falls back to vanilla ops.
|
||||
|
||||
Returns pre-out_proj output [B, S, value_dim] for Dispatch 6.
|
||||
"""
|
||||
B, S, _ = inputs.shape
|
||||
|
||||
# Prefill fallback: fused kernels are decode-only (S=1)
|
||||
if S > 1:
|
||||
return _vanilla_gdn_call(self, inputs, mask, cache)
|
||||
|
||||
from mlx_lm.models.gated_delta import gated_delta_kernel
|
||||
|
||||
# ── Cache: conv state ──
|
||||
if cache is not None and cache[0] is not None:
|
||||
conv_state = cache[0]
|
||||
else:
|
||||
conv_state = mx.zeros(
|
||||
(B, self.conv_kernel_size - 1, self.conv_dim),
|
||||
dtype=inputs.dtype,
|
||||
)
|
||||
|
||||
# ── Dispatch 2: fused projections (merged GEMV + conv + SiLU + g/beta) ──
|
||||
qkv_conv_silu, z_silu, beta, g, conv_state_out = fused_gdn_projections(
|
||||
inputs,
|
||||
self._merged_proj_w, self._merged_proj_s, self._merged_proj_b,
|
||||
self._merged_proj_dims,
|
||||
conv_state, self.conv1d.weight,
|
||||
self.A_log, self.dt_bias,
|
||||
batch_size=B,
|
||||
)
|
||||
|
||||
if cache is not None:
|
||||
cache[0] = conv_state_out
|
||||
|
||||
# ── Dispatch 3: fused Q/K L2-norm ──
|
||||
qk_normed = fused_qk_rmsnorm(qkv_conv_silu, batch_size=B)
|
||||
|
||||
# ── Split q, k from normed output; v from conv output ──
|
||||
q = qk_normed[:, :, :self.key_dim].reshape(B, S, self.num_k_heads, self.head_k_dim)
|
||||
k = qk_normed[:, :, self.key_dim:].reshape(B, S, self.num_k_heads, self.head_k_dim)
|
||||
v = qkv_conv_silu[:, :, 2 * self.key_dim:].reshape(B, S, self.num_v_heads, self.head_v_dim)
|
||||
|
||||
# ── Dispatch 4: GDN recurrence with pre-computed g/beta ──
|
||||
state = cache[1] if cache else None
|
||||
if state is None:
|
||||
state = mx.zeros(
|
||||
(B, self.num_v_heads, self.head_v_dim, self.head_k_dim),
|
||||
dtype=inputs.dtype,
|
||||
)
|
||||
|
||||
out, state_new = gated_delta_kernel(
|
||||
q, k, v, g, beta, state, mask,
|
||||
)
|
||||
|
||||
if cache is not None:
|
||||
cache[1] = state_new
|
||||
|
||||
# ── Dispatch 5: fused RMSNorm × z_silu ──
|
||||
norm_weight = self.norm.weight
|
||||
result = fused_rms_norm_gated(out, z_silu, norm_weight, batch_size=B)
|
||||
|
||||
return result # [B, S, value_dim] — skip out_proj (handled by Dispatch 6)
|
||||
@@ -0,0 +1,137 @@
|
||||
"""Fused GQA attention __call__ for qwen3_next.Qwen3NextAttention.
|
||||
|
||||
Replaces vanilla Qwen3NextAttention.__call__ with fused kernel dispatches:
|
||||
Dispatch 1: fused_gqa_projections — merged 8-bit GEMV (q+gate+k+v) + sigmoid(gate)
|
||||
Dispatch 2: fused_qk_norm_rope — RMSNorm + RoPE (TODO: custom kernel)
|
||||
Dispatch 3: KV cache update (MLX built-in)
|
||||
Dispatch 4: custom_sdpa_pass1 (TODO: custom kernel)
|
||||
Dispatch 5: custom_sdpa_pass2_gate (TODO: custom kernel, includes gate multiply)
|
||||
Dispatch 6: oproj_gate_gemv (existing, handled by MoE __call__)
|
||||
|
||||
Dispatches 1-2, 4-5 are custom kernels, Dispatch 3 is MLX built-in.
|
||||
Returns pre-out_proj output (output * sigmoid(gate)) for Dispatch 6.
|
||||
|
||||
Fused path is decode-only (S=1). For prefill (S>1), falls back to vanilla ops.
|
||||
"""
|
||||
|
||||
from typing import Any, Optional
|
||||
|
||||
import mlx.core as mx
|
||||
import mlx.nn as nn
|
||||
|
||||
from .kernels.fused_gqa_projections_8bit import fused_gqa_projections
|
||||
from .kernels.fused_qk_norm_rope import fused_qk_norm_rope
|
||||
from .kernels.custom_sdpa_pass1 import custom_sdpa_pass1
|
||||
from .kernels.custom_sdpa_pass2_gate import custom_sdpa_pass2_gate
|
||||
|
||||
|
||||
def _vanilla_gqa_call(self, x, mask, cache):
|
||||
"""Vanilla GQA path for prefill (S>1). Returns pre-out_proj output."""
|
||||
B, L, D = x.shape
|
||||
q_proj_output = self.q_proj(x)
|
||||
queries, gate = mx.split(
|
||||
q_proj_output.reshape(B, L, self.num_attention_heads, -1), 2, axis=-1
|
||||
)
|
||||
gate = gate.reshape(B, L, -1)
|
||||
keys, values = self.k_proj(x), self.v_proj(x)
|
||||
queries = self.q_norm(queries).transpose(0, 2, 1, 3)
|
||||
keys = self.k_norm(
|
||||
keys.reshape(B, L, self.num_key_value_heads, -1)
|
||||
).transpose(0, 2, 1, 3)
|
||||
values = values.reshape(B, L, self.num_key_value_heads, -1).transpose(
|
||||
0, 2, 1, 3
|
||||
)
|
||||
if cache is not None:
|
||||
queries = self.rope(queries, offset=cache.offset)
|
||||
keys = self.rope(keys, offset=cache.offset)
|
||||
keys, values = cache.update_and_fetch(keys, values)
|
||||
else:
|
||||
queries = self.rope(queries)
|
||||
keys = self.rope(keys)
|
||||
|
||||
from mlx_lm.models.qwen3_next import scaled_dot_product_attention
|
||||
output = scaled_dot_product_attention(
|
||||
queries, keys, values, cache=cache, scale=self.scale, mask=mask
|
||||
)
|
||||
output = output.transpose(0, 2, 1, 3).reshape(B, L, -1)
|
||||
return output * mx.sigmoid(gate) # skip o_proj
|
||||
|
||||
|
||||
def _fused_gqa_call(
|
||||
self,
|
||||
x: mx.array,
|
||||
mask: Optional[mx.array] = None,
|
||||
cache: Optional[Any] = None,
|
||||
) -> mx.array:
|
||||
"""Fused GQA attention: custom projection + norm/rope kernels.
|
||||
|
||||
Decode (S=1): Dispatch 1 (fused GEMV) + Dispatch 2 (fused norm+rope)
|
||||
+ vanilla cache + SDPA (Dispatches 3-5).
|
||||
Prefill (S>1): falls back to fully vanilla ops.
|
||||
|
||||
Returns pre-out_proj output [B, S, H_q*D] for Dispatch 6.
|
||||
"""
|
||||
B, S, _ = x.shape
|
||||
|
||||
# Prefill fallback: fused kernels are decode-only (S=1)
|
||||
if S > 1:
|
||||
return _vanilla_gqa_call(self, x, mask, cache)
|
||||
|
||||
H_q = self.num_attention_heads
|
||||
H_kv = self.num_key_value_heads
|
||||
D = self.head_dim
|
||||
|
||||
# ── Dispatch 1: fused projections (merged GEMV + sigmoid(gate)) ──
|
||||
sc = getattr(self, '_kernel_scalars', None)
|
||||
queries, gate_sigmoid, keys, values = fused_gqa_projections(
|
||||
x,
|
||||
self._merged_proj_w, self._merged_proj_s, self._merged_proj_b,
|
||||
self._merged_proj_dims,
|
||||
batch_size=B,
|
||||
scalars=sc, total_tg=getattr(self, '_d1_total_tg', None),
|
||||
)
|
||||
|
||||
# ── Dispatch 2: fused Q/K RMSNorm + RoPE ──
|
||||
queries, keys = fused_qk_norm_rope(
|
||||
queries, keys,
|
||||
self.q_norm.weight, self.k_norm.weight,
|
||||
self._rope_inv_freq, cache.offset,
|
||||
H_q, H_kv, D, batch_size=B,
|
||||
)
|
||||
# queries: [B, H_q, 1, D], keys: [B, H_kv, 1, D]
|
||||
# Reshape directly to (B, H_kv, 1, D) — no transpose needed since S=1.
|
||||
# Avoids a 4 MiB copy dispatch that transpose would trigger.
|
||||
values = values.reshape(B, H_kv, 1, D)
|
||||
|
||||
# ── Dispatch 3: KV cache update ──
|
||||
cache.update_and_fetch(keys, values)
|
||||
N = cache.offset # actual sequence length after update
|
||||
alloc_len = cache.keys.shape[2] # allocated buffer length
|
||||
|
||||
# ── Dispatch 4: SDPA Pass 1 (online softmax + partial V accumulation) ──
|
||||
blocks = 128 # M3 Ultra default for N >= 1024
|
||||
if N < 1024:
|
||||
# Short sequence: fall back to vanilla SDPA + gate multiply
|
||||
# Use sliced views for built-in SDPA (handles strides natively)
|
||||
k_sliced = cache.keys[:, :, :N, :]
|
||||
v_sliced = cache.values[:, :, :N, :]
|
||||
from mlx_lm.models.qwen3_next import scaled_dot_product_attention
|
||||
output = scaled_dot_product_attention(
|
||||
queries, k_sliced, v_sliced, cache=cache, scale=self.scale, mask=mask
|
||||
)
|
||||
output = output.transpose(0, 2, 1, 3).reshape(B, S, -1)
|
||||
return output * gate_sigmoid.astype(output.dtype)
|
||||
|
||||
# Pass full (contiguous) cache buffers + alloc_len to avoid copy dispatch
|
||||
o_partials, sums, maxs = custom_sdpa_pass1(
|
||||
queries, cache.keys, cache.values, self.scale,
|
||||
H_q, H_kv, D, blocks=blocks, batch_size=B,
|
||||
N=N, alloc_len=alloc_len, scalars=sc,
|
||||
)
|
||||
|
||||
# ── Dispatch 5: SDPA Pass 2 + gate multiply ──
|
||||
return custom_sdpa_pass2_gate(
|
||||
o_partials, sums, maxs, gate_sigmoid,
|
||||
H_q, D, blocks=blocks, V_SPLIT=4, batch_size=B,
|
||||
scalars=sc,
|
||||
)
|
||||
@@ -0,0 +1,216 @@
|
||||
"""Custom SDPA Pass 1 for GQA attention (Dispatch 4).
|
||||
|
||||
Replicates MLX's sdpa_vector_2pass_1 kernel for decode (query_len=1).
|
||||
Online softmax over N key positions, strided by `blocks`.
|
||||
|
||||
Each TG = (32, gqa_factor, 1):
|
||||
- 32 threads in x = 1 SIMD group, each handles D/32 = 8 Q/K/V elements
|
||||
- gqa_factor threads in y = one per Q head sharing the same KV head
|
||||
- Grid z = blocks (each block handles a stride of the key sequence)
|
||||
|
||||
Algorithm per block:
|
||||
1. Load query (once), scale by 1/sqrt(D)
|
||||
2. For each key position i in [block_idx, N) with stride `blocks`:
|
||||
a. Dot product: score = sum(q[j] * k[i,j]) via simd_sum
|
||||
b. Online softmax: update max, sum_exp, rescale accumulators
|
||||
c. Accumulate: o[j] += exp_score * v[i,j]
|
||||
3. Write partials: o_partials[block, head, D], sums[block, head], maxs[block, head]
|
||||
|
||||
Matches MLX's sdpa_vector_2pass_1<bfloat16_t, 256, 256> exactly.
|
||||
"""
|
||||
|
||||
import mlx.core as mx
|
||||
|
||||
|
||||
def _gen_sdpa_pass1_source(D=256):
|
||||
"""Generate Metal source for SDPA Pass 1.
|
||||
|
||||
Replicates MLX's sdpa_vector_2pass_1 for decode (S_q=1, no mask).
|
||||
|
||||
Inputs:
|
||||
queries: [B, H_q, 1, D] bf16 (pre-scaled by 1/sqrt(D) NOT done here)
|
||||
keys: [B, H_kv, alloc_len, D] bf16 (full cache buffer)
|
||||
values: [B, H_kv, alloc_len, D] bf16 (full cache buffer)
|
||||
scale: scalar f32
|
||||
KV_alloc_len: int (allocated cache length, for head stride computation)
|
||||
|
||||
Outputs:
|
||||
o_partials: [B, H_q, blocks, D] bf16
|
||||
sums: [B, H_q, blocks] f32
|
||||
maxs: [B, H_q, blocks] f32
|
||||
|
||||
Grid: (H_kv * 32, gqa_factor, blocks * B)
|
||||
TG: (32, gqa_factor, 1)
|
||||
|
||||
We use grid.z = blocks * B to encode both block_idx and batch_idx:
|
||||
block_idx = tgid.z % blocks
|
||||
batch_idx = tgid.z / blocks
|
||||
"""
|
||||
EPT = D // 32 # elements per thread = 8
|
||||
|
||||
return f"""
|
||||
const int D_DIM = {D};
|
||||
const int EPT = {EPT};
|
||||
|
||||
uint simd_lid = thread_index_in_simdgroup;
|
||||
uint kv_head_idx = threadgroup_position_in_grid.x;
|
||||
uint gqa_lane = thread_index_in_threadgroup / 32; // which Q head within GQA group
|
||||
|
||||
// Decode block_idx and batch_idx from grid z
|
||||
uint block_idx = threadgroup_position_in_grid.z % (uint)N_blocks;
|
||||
uint batch_idx = threadgroup_position_in_grid.z / (uint)N_blocks;
|
||||
|
||||
int gqa_factor_val = (int)H_Q / (int)H_KV;
|
||||
int q_head_idx = (int)kv_head_idx * gqa_factor_val + (int)gqa_lane;
|
||||
int N_val = (int)N_keys;
|
||||
|
||||
// ── Pointer offsets ──
|
||||
// queries: [B, H_q, 1, D] — one query per head
|
||||
int q_offset = ((int)batch_idx * (int)H_Q + q_head_idx) * D_DIM;
|
||||
|
||||
// keys/values: [B, H_kv, alloc_len, D] — full cache buffer, read only first N_val positions
|
||||
// Use alloc_len for head stride (not N_val) to handle non-contiguous cache slices
|
||||
int alloc = (int)KV_alloc_len;
|
||||
int kv_head_offset = ((int)batch_idx * (int)H_KV + (int)kv_head_idx) * alloc * D_DIM;
|
||||
int k_offset = kv_head_offset + (int)block_idx * D_DIM;
|
||||
int v_offset = kv_head_offset + (int)block_idx * D_DIM;
|
||||
|
||||
// Output offsets: indexed by [batch, q_head, block]
|
||||
int out_head_offset = ((int)batch_idx * (int)H_Q + q_head_idx);
|
||||
int o_offset = (out_head_offset * (int)N_blocks + (int)block_idx) * D_DIM;
|
||||
int s_offset = out_head_offset * (int)N_blocks + (int)block_idx;
|
||||
|
||||
// ── Load query (once, scaled) ──
|
||||
float q[{EPT}];
|
||||
for (int i = 0; i < EPT; i++) {{
|
||||
q[i] = (float)scale * (float)queries[q_offset + (int)simd_lid * EPT + i];
|
||||
}}
|
||||
|
||||
// ── Online softmax + V accumulation ──
|
||||
float max_score = -__FLT_MAX__;
|
||||
float sum_exp = 0.0f;
|
||||
float o[{EPT}] = {{0}};
|
||||
|
||||
int k_stride = (int)N_blocks * D_DIM; // stride between consecutive keys for this block
|
||||
|
||||
for (int pos = (int)block_idx; pos < N_val; pos += (int)N_blocks) {{
|
||||
// Dot product: q @ k[pos]
|
||||
float score = 0.0f;
|
||||
for (int i = 0; i < EPT; i++) {{
|
||||
score += q[i] * (float)keys[k_offset + (int)simd_lid * EPT + i];
|
||||
}}
|
||||
score = simd_sum(score);
|
||||
|
||||
// Online softmax update
|
||||
float new_max = metal::max(max_score, score);
|
||||
float factor = metal::fast::exp(max_score - new_max);
|
||||
float exp_score = metal::fast::exp(score - new_max);
|
||||
|
||||
max_score = new_max;
|
||||
sum_exp = sum_exp * factor + exp_score;
|
||||
|
||||
// Accumulate weighted value
|
||||
for (int i = 0; i < EPT; i++) {{
|
||||
o[i] = o[i] * factor + exp_score * (float)values[v_offset + (int)simd_lid * EPT + i];
|
||||
}}
|
||||
|
||||
// Advance to next position for this block
|
||||
k_offset += k_stride;
|
||||
v_offset += k_stride;
|
||||
}}
|
||||
|
||||
// ── Write partials ──
|
||||
if (simd_lid == 0) {{
|
||||
sums[s_offset] = sum_exp;
|
||||
maxs[s_offset] = max_score;
|
||||
}}
|
||||
|
||||
for (int i = 0; i < EPT; i++) {{
|
||||
o_partials[o_offset + (int)simd_lid * EPT + i] = static_cast<bfloat16_t>(o[i]);
|
||||
}}
|
||||
"""
|
||||
|
||||
|
||||
_pass1_cache = {}
|
||||
|
||||
|
||||
def _get_pass1_kernel(D, gqa_factor):
|
||||
"""Get or compile the SDPA Pass 1 kernel."""
|
||||
key = (D, gqa_factor)
|
||||
if key not in _pass1_cache:
|
||||
_pass1_cache[key] = mx.fast.metal_kernel(
|
||||
name="custom_sdpa_pass1",
|
||||
input_names=["queries", "keys", "values",
|
||||
"scale", "H_Q", "H_KV", "N_keys", "N_blocks",
|
||||
"KV_alloc_len"],
|
||||
output_names=["o_partials", "sums", "maxs"],
|
||||
source=_gen_sdpa_pass1_source(D),
|
||||
)
|
||||
return _pass1_cache[key]
|
||||
|
||||
|
||||
def custom_sdpa_pass1(queries, keys, values, scale, H_q, H_kv, D,
|
||||
blocks=128, batch_size=1, N=None, alloc_len=None,
|
||||
scalars=None):
|
||||
"""SDPA Pass 1: online softmax + partial V accumulation.
|
||||
|
||||
Args:
|
||||
queries: [B, H_q, 1, D] bf16
|
||||
keys: [B, H_kv, N_or_alloc, D] bf16 — can be full cache buffer
|
||||
values: [B, H_kv, N_or_alloc, D] bf16 — can be full cache buffer
|
||||
scale: float (1/sqrt(D))
|
||||
H_q, H_kv, D: int
|
||||
blocks: int (number of blocks, default 128 for M3 Ultra)
|
||||
batch_size: int
|
||||
N: actual sequence length (if None, inferred from keys.shape[2])
|
||||
alloc_len: allocated cache length (if None, same as N — contiguous)
|
||||
scalars: dict of pre-cached mx.array scalars (optional)
|
||||
|
||||
Returns:
|
||||
o_partials: [B, H_q, blocks, D] bf16
|
||||
sums: [B, H_q, blocks] f32
|
||||
maxs: [B, H_q, blocks] f32
|
||||
"""
|
||||
B = batch_size
|
||||
gqa_factor = H_q // H_kv
|
||||
|
||||
kern = _get_pass1_kernel(D, gqa_factor)
|
||||
|
||||
if N is None:
|
||||
N = keys.shape[2]
|
||||
if alloc_len is None:
|
||||
alloc_len = N
|
||||
|
||||
if scalars is not None:
|
||||
s = scalars
|
||||
# N and alloc_len change per call, must create fresh
|
||||
n_keys_arr = mx.array(N, dtype=mx.int32)
|
||||
alloc_arr = mx.array(alloc_len, dtype=mx.int32)
|
||||
inputs = [queries, keys, values,
|
||||
s['scale'], s['H_Q'], s['H_KV'], n_keys_arr, s['N_blocks'],
|
||||
alloc_arr]
|
||||
else:
|
||||
inputs = [queries, keys, values,
|
||||
mx.array(scale, dtype=mx.float32),
|
||||
mx.array(H_q, dtype=mx.int32),
|
||||
mx.array(H_kv, dtype=mx.int32),
|
||||
mx.array(N, dtype=mx.int32),
|
||||
mx.array(blocks, dtype=mx.int32),
|
||||
mx.array(alloc_len, dtype=mx.int32)]
|
||||
|
||||
results = kern(
|
||||
inputs=inputs,
|
||||
output_shapes=[
|
||||
(B * H_q * blocks * D,), # o_partials
|
||||
(B * H_q * blocks,), # sums
|
||||
(B * H_q * blocks,), # maxs
|
||||
],
|
||||
output_dtypes=[mx.bfloat16, mx.float32, mx.float32],
|
||||
grid=(H_kv * 32, gqa_factor, blocks * B),
|
||||
threadgroup=(32, gqa_factor, 1),
|
||||
)
|
||||
|
||||
o_partials = results[0].reshape(B, H_q, blocks, D)
|
||||
sums = results[1].reshape(B, H_q, blocks)
|
||||
maxs = results[2].reshape(B, H_q, blocks)
|
||||
return o_partials, sums, maxs
|
||||
@@ -0,0 +1,200 @@
|
||||
"""Custom SDPA Pass 2 + gate multiply for GQA attention (Dispatch 5).
|
||||
|
||||
Combines the block-partial results from Pass 1 into final SDPA output,
|
||||
with gate multiply epilogue: output *= gate_sigmoid.
|
||||
|
||||
Modeled on MLX's sdpa_vector_2pass_2 kernel with two improvements:
|
||||
1. V-dimension splitting (V_SPLIT=4): Instead of 1 TG per head (16 TGs,
|
||||
20% M3 Ultra utilization), split the 256-dim output across 4 TGs per
|
||||
head -> 64 TGs (80% utilization).
|
||||
2. Gate multiply epilogue: Apply output *= gate_sigmoid in the same kernel.
|
||||
|
||||
Each TG = 1024 threads (32 SGs × 32 threads), matching MLX's structure:
|
||||
- Handles D/V_SPLIT = 64 V-dimensions per TG
|
||||
- 32 SGs process 32 blocks in parallel per iteration
|
||||
- blocks/32 = 4 iterations to cover all 128 blocks
|
||||
- Shared memory transpose + simd_sum to reduce across SGs
|
||||
- Each thread handles EPT = 2 V-elements
|
||||
|
||||
Grid: (H_q * V_SPLIT * 32, 32, B)
|
||||
TG: (32, 32, 1)
|
||||
"""
|
||||
|
||||
import mlx.core as mx
|
||||
|
||||
|
||||
def _gen_sdpa_pass2_gate_source(D=256, V_SPLIT=4):
|
||||
"""Generate Metal source for SDPA Pass 2 + gate multiply.
|
||||
|
||||
Modeled on MLX's sdpa_vector_2pass_2 but with V_SPLIT for higher
|
||||
TG count and fused gate multiply epilogue.
|
||||
|
||||
Inputs:
|
||||
o_partials: [B, H_q, blocks, D] bf16
|
||||
sums: [B, H_q, blocks] f32
|
||||
maxs: [B, H_q, blocks] f32
|
||||
gate_sigmoid: [B, 1, H_q * D] f32
|
||||
|
||||
Output:
|
||||
attn_output: [B, 1, H_q * D] bf16
|
||||
|
||||
TG assignment:
|
||||
tgid.x = head_idx * V_SPLIT + split_idx
|
||||
Each TG handles D/V_SPLIT V-elements for one head.
|
||||
32 SGs within TG process blocks in parallel.
|
||||
"""
|
||||
BN = 32 # number of SGs per TG = blocks processed in parallel
|
||||
V_PER_SPLIT = D // V_SPLIT # 64
|
||||
EPT = V_PER_SPLIT // BN # 2 elements per thread
|
||||
|
||||
return f"""
|
||||
const int D_DIM = {D};
|
||||
const int V_SPLIT = {V_SPLIT};
|
||||
const int V_PER_SPLIT = {V_PER_SPLIT};
|
||||
const int EPT = {EPT};
|
||||
const int BN = {BN};
|
||||
|
||||
uint tg_idx = threadgroup_position_in_grid.x;
|
||||
uint simd_gid = simdgroup_index_in_threadgroup; // 0..31 (which SG = block offset)
|
||||
uint simd_lid = thread_index_in_simdgroup; // 0..31 (thread within SG)
|
||||
uint b_idx = threadgroup_position_in_grid.z;
|
||||
|
||||
int head_idx = (int)tg_idx / V_SPLIT;
|
||||
int split_idx = (int)tg_idx % V_SPLIT;
|
||||
int v_offset = split_idx * V_PER_SPLIT;
|
||||
|
||||
int blocks_val = (int)N_blocks;
|
||||
int h_q_val = (int)H_Q;
|
||||
|
||||
// Base offset into partials/maxs/sums for this head: [B, H_q, blocks, ...]
|
||||
int head_base = ((int)b_idx * h_q_val + head_idx);
|
||||
|
||||
// Pointer setup for partials: [B, H_q, blocks, D]
|
||||
// Each SG starts at a different block, reads EPT V-elements at v_offset
|
||||
int p_base = head_base * blocks_val * D_DIM
|
||||
+ (int)simd_gid * D_DIM
|
||||
+ v_offset + (int)simd_lid * EPT;
|
||||
int ms_base = head_base * blocks_val;
|
||||
|
||||
// ── Phase 1: Find global max across all blocks ──
|
||||
// Each of 32 simd_lids processes blocks/32 = 4 blocks (strided)
|
||||
float local_max = -__FLT_MAX__;
|
||||
for (int b = 0; b < blocks_val / BN; ++b) {{
|
||||
local_max = metal::max(local_max, maxs[ms_base + (int)simd_lid + BN * b]);
|
||||
}}
|
||||
float global_max = simd_max(local_max);
|
||||
|
||||
// ── Phase 2: Compute global sum_exp ──
|
||||
float local_sum = 0.0f;
|
||||
for (int b = 0; b < blocks_val / BN; ++b) {{
|
||||
float factor = metal::fast::exp(maxs[ms_base + (int)simd_lid + BN * b] - global_max);
|
||||
local_sum += factor * sums[ms_base + (int)simd_lid + BN * b];
|
||||
}}
|
||||
float global_sum = simd_sum(local_sum);
|
||||
|
||||
// ── Phase 3: Accumulate V-partials (block-parallel via SGs) ──
|
||||
// 32 SGs process 32 blocks simultaneously, 4 iterations for 128 blocks.
|
||||
// Each SG reads EPT V-elements from its assigned block.
|
||||
float o[EPT] = {{0}};
|
||||
for (int b = 0; b < blocks_val / BN; ++b) {{
|
||||
float factor = metal::fast::exp(maxs[ms_base + (int)simd_gid] - global_max);
|
||||
for (int i = 0; i < EPT; i++) {{
|
||||
o[i] += factor * (float)o_partials[p_base + i];
|
||||
}}
|
||||
// Advance maxs by BN and partials by BN * D
|
||||
ms_base += BN;
|
||||
p_base += BN * D_DIM;
|
||||
}}
|
||||
|
||||
// ── Phase 4: Shared memory transpose + reduce across SGs ──
|
||||
// Each SG has accumulated partials for different blocks but same V-elements.
|
||||
// Transpose so each SG's threads hold all block contributions for the same V position,
|
||||
// then simd_sum reduces them.
|
||||
threadgroup float tg_mem[BN * BN]; // 32×32 = 1024 floats = 4 KB
|
||||
|
||||
for (int i = 0; i < EPT; i++) {{
|
||||
tg_mem[(int)simd_lid * BN + (int)simd_gid] = o[i];
|
||||
threadgroup_barrier(mem_flags::mem_threadgroup);
|
||||
o[i] = simd_sum(tg_mem[(int)simd_gid * BN + (int)simd_lid]);
|
||||
threadgroup_barrier(mem_flags::mem_threadgroup);
|
||||
}}
|
||||
|
||||
// ── Phase 5: Normalize + gate multiply + write (simd_lid == 0 only) ──
|
||||
if (simd_lid == 0) {{
|
||||
float inv_sum = (global_sum > 0.0f) ? (1.0f / global_sum) : 0.0f;
|
||||
int out_base = (int)b_idx * h_q_val * D_DIM + head_idx * D_DIM
|
||||
+ v_offset + (int)simd_gid * EPT;
|
||||
for (int i = 0; i < EPT; i++) {{
|
||||
float val = o[i] * inv_sum;
|
||||
float gate = gate_sigmoid[out_base + i];
|
||||
attn_output[out_base + i] = static_cast<bfloat16_t>(val * gate);
|
||||
}}
|
||||
}}
|
||||
"""
|
||||
|
||||
|
||||
_pass2_cache = {}
|
||||
|
||||
|
||||
def _get_pass2_kernel(D, V_SPLIT):
|
||||
"""Get or compile the SDPA Pass 2 + gate kernel."""
|
||||
key = (D, V_SPLIT)
|
||||
if key not in _pass2_cache:
|
||||
_pass2_cache[key] = mx.fast.metal_kernel(
|
||||
name="custom_sdpa_pass2_gate",
|
||||
input_names=["o_partials", "sums", "maxs", "gate_sigmoid",
|
||||
"H_Q", "N_blocks"],
|
||||
output_names=["attn_output"],
|
||||
source=_gen_sdpa_pass2_gate_source(D, V_SPLIT),
|
||||
)
|
||||
return _pass2_cache[key]
|
||||
|
||||
|
||||
def custom_sdpa_pass2_gate(o_partials, sums, maxs, gate_sigmoid,
|
||||
H_q, D, blocks=128, V_SPLIT=4, batch_size=1,
|
||||
scalars=None):
|
||||
"""SDPA Pass 2: reduce block partials + gate multiply.
|
||||
|
||||
Args:
|
||||
o_partials: [B, H_q, blocks, D] bf16 — from Pass 1.
|
||||
sums: [B, H_q, blocks] f32 — from Pass 1.
|
||||
maxs: [B, H_q, blocks] f32 — from Pass 1.
|
||||
gate_sigmoid: [B, 1, H_q*D] f32 — from Dispatch 1.
|
||||
H_q: int — number of query heads.
|
||||
D: int — head dimension.
|
||||
blocks: int — number of blocks from Pass 1.
|
||||
V_SPLIT: int — V-dimension split factor (4 for 80% M3 Ultra util).
|
||||
batch_size: int
|
||||
scalars: dict of pre-cached mx.array scalars (optional)
|
||||
|
||||
Returns:
|
||||
attn_output: [B, 1, H_q*D] bf16 — final gated attention output.
|
||||
"""
|
||||
B = batch_size
|
||||
|
||||
kern = _get_pass2_kernel(D, V_SPLIT)
|
||||
|
||||
if scalars is not None:
|
||||
h_q_arr = scalars['H_Q']
|
||||
n_blocks_arr = scalars['N_blocks']
|
||||
else:
|
||||
h_q_arr = mx.array(H_q, dtype=mx.int32)
|
||||
n_blocks_arr = mx.array(blocks, dtype=mx.int32)
|
||||
|
||||
# Flatten inputs for kernel
|
||||
o_flat = o_partials.reshape(B * H_q * blocks * D)
|
||||
s_flat = sums.reshape(B * H_q * blocks)
|
||||
m_flat = maxs.reshape(B * H_q * blocks)
|
||||
g_flat = gate_sigmoid.reshape(B * H_q * D)
|
||||
|
||||
n_tgs = H_q * V_SPLIT
|
||||
BN = 32 # SGs per TG
|
||||
results = kern(
|
||||
inputs=[o_flat, s_flat, m_flat, g_flat, h_q_arr, n_blocks_arr],
|
||||
output_shapes=[(B * H_q * D,)],
|
||||
output_dtypes=[mx.bfloat16],
|
||||
grid=(n_tgs * BN, BN, B),
|
||||
threadgroup=(BN, BN, 1),
|
||||
)
|
||||
|
||||
return results[0].reshape(B, 1, H_q * D)
|
||||
@@ -0,0 +1,313 @@
|
||||
"""Fused GDN projections for Qwen3.5-35B-A3B (Dispatch 2).
|
||||
|
||||
Single dispatch fuses 4 quantized 8-bit GEMVs + depthwise conv1d + activations:
|
||||
- in_proj_qkv (8192×2048): GEMV → conv1d(4-tap) → SiLU → write bf16 + cache update
|
||||
- in_proj_z (4096×2048): GEMV → SiLU → write f32
|
||||
- in_proj_b (32×2048): GEMV → sigmoid → write f32 (beta for GDN kernel)
|
||||
- in_proj_a (32×2048): GEMV → g=exp(-exp(A_log)*softplus(a+dt_bias)) → write f32
|
||||
|
||||
All 4 projection weight matrices are pre-merged into one contiguous buffer
|
||||
(W_merged, S_merged, B_merged) for better memory locality and cache behavior.
|
||||
Merging is done offline at patch time by _patch_gdn_proj_weights().
|
||||
|
||||
B/A epilogues compute g and beta in-kernel, eliminating ~8 micro-dispatches
|
||||
that gated_delta_update would otherwise generate (sigmoid, exp, log, etc.).
|
||||
The caller can pass g/beta directly to gated_delta_kernel.
|
||||
|
||||
TG-level multiplexing: tgid.y routes to different epilogues.
|
||||
Each TG: 64 threads = 2 SGs of 32, produces 8 output rows (4 per SG).
|
||||
Standard 8-bit affine GEMV: result = scale * Σ(x[i]*w[i]) + bias * Σ(x[i])
|
||||
|
||||
Grid: (32, total_tg * 2, B), TG: (32, 2, 1)
|
||||
"""
|
||||
|
||||
import mlx.core as mx
|
||||
|
||||
|
||||
def ceil_div(a, b):
|
||||
return (a + b - 1) // b
|
||||
|
||||
|
||||
def _gen_fused_gdn_projections_source(group_size=64):
|
||||
"""Generate Metal source for fused GDN projections with merged weights.
|
||||
|
||||
8-bit dequantization (group_size=64):
|
||||
result = scale * Σ(x[i]*w[i]) + bias * Σ(x[i])
|
||||
|
||||
Single merged weight buffer indexed by absolute out_row.
|
||||
TG routing via tgid.y determines region (epilogue):
|
||||
[0, N_QKV_TG): QKV GEMV + conv1d + SiLU + cache
|
||||
[N_QKV_TG, +N_Z_TG): Z GEMV + SiLU
|
||||
[+N_Z_TG, +N_B_TG): B GEMV → sigmoid → beta (f32)
|
||||
[+N_B_TG, +N_A_TG): A GEMV → g=exp(-exp(A_log)*softplus(a+dt_bias)) (f32)
|
||||
"""
|
||||
gs = int(group_size)
|
||||
sc_stride = 256 // gs # groups consumed per K-block = 4
|
||||
slid_div = gs // 8 # threads per group = 8
|
||||
|
||||
return f"""
|
||||
const int RESULTS_PER_SG = 4;
|
||||
const int VALUES_PER_THREAD = 8;
|
||||
const int BLOCK_SIZE = 256; // 32 * 8
|
||||
const int GROUP_SIZE = {gs};
|
||||
const int SC_STRIDE = {sc_stride};
|
||||
const int SLID_DIV = {slid_div};
|
||||
|
||||
int K = K_val;
|
||||
int K_groups = K / GROUP_SIZE;
|
||||
|
||||
// Dimension boundaries
|
||||
int N_QKV = N_QKV_val;
|
||||
int N_Z = N_Z_val;
|
||||
int N_B = N_B_val;
|
||||
int N_TOTAL = N_TOTAL_val;
|
||||
|
||||
// TG boundaries
|
||||
int N_QKV_TG = N_QKV_TG_val;
|
||||
int N_Z_TG = N_Z_TG_val;
|
||||
int N_B_TG = N_B_TG_val;
|
||||
|
||||
uint3 tgid = threadgroup_position_in_grid;
|
||||
uint sgid = simdgroup_index_in_threadgroup; // 0 or 1
|
||||
uint slid = thread_index_in_simdgroup; // 0..31
|
||||
int b_idx = tgid.z;
|
||||
|
||||
int tg = tgid.y;
|
||||
|
||||
// ─── Determine region and absolute out_row in merged matrix ───
|
||||
int out_row;
|
||||
int region; // 0=QKV, 1=Z, 2=B, 3=A
|
||||
|
||||
if (tg < N_QKV_TG) {{
|
||||
region = 0;
|
||||
out_row = tg * 8 + sgid * RESULTS_PER_SG;
|
||||
}} else if (tg < N_QKV_TG + N_Z_TG) {{
|
||||
region = 1;
|
||||
out_row = N_QKV + (tg - N_QKV_TG) * 8 + sgid * RESULTS_PER_SG;
|
||||
}} else if (tg < N_QKV_TG + N_Z_TG + N_B_TG) {{
|
||||
region = 2;
|
||||
out_row = N_QKV + N_Z + (tg - N_QKV_TG - N_Z_TG) * 8 + sgid * RESULTS_PER_SG;
|
||||
}} else {{
|
||||
region = 3;
|
||||
out_row = N_QKV + N_Z + N_B + (tg - N_QKV_TG - N_Z_TG - N_B_TG) * 8 + sgid * RESULTS_PER_SG;
|
||||
}}
|
||||
|
||||
if (out_row >= N_TOTAL) return;
|
||||
|
||||
// ─── Single pointer into merged weight buffer ───
|
||||
const device uint8_t* ws = (const device uint8_t*)W_merged + (long)out_row * K + slid * VALUES_PER_THREAD;
|
||||
const device bfloat16_t* sc = (const device bfloat16_t*)S_merged + (long)out_row * K_groups + slid / SLID_DIV;
|
||||
const device bfloat16_t* bi = (const device bfloat16_t*)B_merged + (long)out_row * K_groups + slid / SLID_DIV;
|
||||
|
||||
// ─── 8-bit GEMV K-loop (unified for all regions) ───
|
||||
float result[4] = {{0, 0, 0, 0}};
|
||||
int x_base = b_idx * K + slid * VALUES_PER_THREAD;
|
||||
|
||||
for (int k_off = 0; k_off < K; k_off += BLOCK_SIZE) {{
|
||||
float x_thread[8];
|
||||
float xsum = 0;
|
||||
for (int i = 0; i < 8; i++) {{
|
||||
float xi = float(x[x_base + i]);
|
||||
x_thread[i] = xi;
|
||||
xsum += xi;
|
||||
}}
|
||||
|
||||
for (int row = 0; row < RESULTS_PER_SG; row++) {{
|
||||
const device uint8_t* w = ws + row * K;
|
||||
float s_val = float(sc[row * K_groups]);
|
||||
float b_val = float(bi[row * K_groups]);
|
||||
float accum = 0;
|
||||
for (int i = 0; i < 8; i++) {{
|
||||
accum += x_thread[i] * float(w[i]);
|
||||
}}
|
||||
result[row] += s_val * accum + xsum * b_val;
|
||||
}}
|
||||
|
||||
ws += BLOCK_SIZE;
|
||||
sc += SC_STRIDE;
|
||||
bi += SC_STRIDE;
|
||||
x_base += BLOCK_SIZE;
|
||||
}}
|
||||
|
||||
// ─── Reduction ───
|
||||
for (int row = 0; row < RESULTS_PER_SG; row++) {{
|
||||
result[row] = simd_sum(result[row]);
|
||||
}}
|
||||
|
||||
// ─── Region-specific epilogues ───
|
||||
// After simd_sum, all 32 threads have result[0..3].
|
||||
// Threads 0-3 each handle one output row.
|
||||
|
||||
if (region == 0) {{
|
||||
// ═══ QKV: conv1d(4-tap) + SiLU + cache update ═══
|
||||
int c = out_row + (int)slid; // channel index (= absolute row for QKV)
|
||||
if (slid < (uint)RESULTS_PER_SG && c < N_QKV) {{
|
||||
float qkv_val = result[slid];
|
||||
|
||||
int conv_dim = N_QKV;
|
||||
long cs_base = (long)b_idx * 3 * conv_dim;
|
||||
float s0 = float(conv_state[cs_base + 0 * conv_dim + c]);
|
||||
float s1 = float(conv_state[cs_base + 1 * conv_dim + c]);
|
||||
float s2 = float(conv_state[cs_base + 2 * conv_dim + c]);
|
||||
|
||||
float conv_out = float(conv_w[c * 4 + 0]) * s0
|
||||
+ float(conv_w[c * 4 + 1]) * s1
|
||||
+ float(conv_w[c * 4 + 2]) * s2
|
||||
+ float(conv_w[c * 4 + 3]) * qkv_val;
|
||||
|
||||
float silu_out = conv_out / (1.0f + metal::exp(-conv_out));
|
||||
|
||||
conv_state_out[cs_base + 0 * conv_dim + c] = static_cast<bfloat16_t>(s1);
|
||||
conv_state_out[cs_base + 1 * conv_dim + c] = static_cast<bfloat16_t>(s2);
|
||||
conv_state_out[cs_base + 2 * conv_dim + c] = static_cast<bfloat16_t>(qkv_val);
|
||||
|
||||
qkv_out[b_idx * conv_dim + c] = static_cast<bfloat16_t>(silu_out);
|
||||
}}
|
||||
|
||||
}} else if (region == 1) {{
|
||||
// ═══ Z: SiLU → write f32 ═══
|
||||
int z_row = out_row - N_QKV + (int)slid;
|
||||
if (slid < (uint)RESULTS_PER_SG && z_row < N_Z) {{
|
||||
float val = result[slid];
|
||||
float silu_val = val / (1.0f + metal::exp(-val));
|
||||
z_silu_out[b_idx * N_Z + z_row] = silu_val;
|
||||
}}
|
||||
|
||||
}} else if (region == 2) {{
|
||||
// ═══ B: sigmoid(result) → beta (f32) ═══
|
||||
int b_row = out_row - N_QKV - N_Z + (int)slid;
|
||||
if (slid < (uint)RESULTS_PER_SG && b_row < N_B) {{
|
||||
float val = result[slid];
|
||||
float beta = 1.0f / (1.0f + metal::exp(-val));
|
||||
b_out[b_idx * N_B + b_row] = beta;
|
||||
}}
|
||||
|
||||
}} else {{
|
||||
// ═══ A: g = exp(-exp(A_log) * softplus(a + dt_bias)) → f32 ═══
|
||||
int a_row = out_row - N_QKV - N_Z - N_B + (int)slid;
|
||||
int N_A = N_TOTAL - N_QKV - N_Z - N_B;
|
||||
if (slid < (uint)RESULTS_PER_SG && a_row < N_A) {{
|
||||
float a_val = result[slid];
|
||||
float dt = float(dt_bias_arr[a_row]);
|
||||
float x_g = a_val + dt;
|
||||
// softplus(x) = log(1 + exp(x)), with x>20 shortcut for numerical stability
|
||||
float sp = (x_g > 20.0f) ? x_g : metal::log(1.0f + metal::exp(x_g));
|
||||
float g_val = metal::exp(-metal::exp(float(A_log_arr[a_row])) * sp);
|
||||
a_out[b_idx * N_A + a_row] = g_val;
|
||||
}}
|
||||
}}
|
||||
"""
|
||||
|
||||
|
||||
_fused_gdn_proj_kernel = None
|
||||
|
||||
|
||||
def _get_fused_gdn_proj_kernel():
|
||||
"""Get or compile the fused GDN projections kernel."""
|
||||
global _fused_gdn_proj_kernel
|
||||
if _fused_gdn_proj_kernel is None:
|
||||
_fused_gdn_proj_kernel = mx.fast.metal_kernel(
|
||||
name="fused_gdn_projections_8bit_merged",
|
||||
input_names=[
|
||||
"x",
|
||||
"W_merged", "S_merged", "B_merged",
|
||||
"conv_state", "conv_w",
|
||||
"A_log_arr", "dt_bias_arr",
|
||||
"K_val",
|
||||
"N_QKV_val", "N_Z_val", "N_B_val", "N_TOTAL_val",
|
||||
"N_QKV_TG_val", "N_Z_TG_val", "N_B_TG_val",
|
||||
],
|
||||
output_names=["qkv_out", "z_silu_out", "b_out", "a_out", "conv_state_out"],
|
||||
source=_gen_fused_gdn_projections_source(),
|
||||
)
|
||||
return _fused_gdn_proj_kernel
|
||||
|
||||
|
||||
def fused_gdn_projections(
|
||||
x,
|
||||
W_merged, S_merged, B_merged,
|
||||
proj_dims,
|
||||
conv_state, conv_weights,
|
||||
A_log, dt_bias,
|
||||
batch_size=1,
|
||||
):
|
||||
"""Fused GDN projections: 4 GEMVs + conv1d + activations + g/beta.
|
||||
|
||||
Uses pre-merged contiguous weight buffers for all 4 projections.
|
||||
B epilogue computes beta = sigmoid(b) in f32.
|
||||
A epilogue computes g = exp(-exp(A_log) * softplus(a + dt_bias)) in f32.
|
||||
Caller passes g/beta directly to gated_delta_kernel (no micro-dispatches).
|
||||
|
||||
Args:
|
||||
x: [B, 1, K] bf16 — post-RMSNorm hidden state
|
||||
W_merged: [N_TOTAL, K/4] uint32 — merged quantized weights
|
||||
S_merged: [N_TOTAL, K/gs] bf16 — merged scales
|
||||
B_merged: [N_TOTAL, K/gs] bf16 — merged biases
|
||||
proj_dims: (N_QKV, N_Z, N_B, N_A) — per-projection output dims
|
||||
conv_state: [B, 3, conv_dim] bf16 — previous 3 timesteps
|
||||
conv_weights: [conv_dim, 4, 1] or [conv_dim, 4] bf16 — depthwise conv filters
|
||||
A_log: [Hv] f32 — GDN decay log-parameter
|
||||
dt_bias: [Hv] f32 — GDN time constant bias
|
||||
batch_size: int
|
||||
|
||||
Returns:
|
||||
qkv_conv_silu: [B, 1, N_QKV] bf16 — post-conv, post-SiLU
|
||||
z_silu: [B, 1, N_Z] f32 — post-SiLU
|
||||
beta: [B, 1, N_B] f32 — sigmoid(b), ready for GDN kernel
|
||||
g: [B, 1, N_A] f32 — gating, ready for GDN kernel
|
||||
conv_state_out: [B, 3, N_QKV] bf16
|
||||
"""
|
||||
B = batch_size
|
||||
kern = _get_fused_gdn_proj_kernel()
|
||||
|
||||
N_QKV, N_Z, N_B, N_A = proj_dims
|
||||
N_TOTAL = N_QKV + N_Z + N_B + N_A
|
||||
K = x.shape[-1]
|
||||
|
||||
# TG counts (8 rows per TG)
|
||||
N_QKV_TG = ceil_div(N_QKV, 8)
|
||||
N_Z_TG = ceil_div(N_Z, 8)
|
||||
N_B_TG = ceil_div(N_B, 8)
|
||||
N_A_TG = ceil_div(N_A, 8)
|
||||
total_tg = N_QKV_TG + N_Z_TG + N_B_TG + N_A_TG
|
||||
|
||||
# Flatten conv weights to [conv_dim, 4] if needed
|
||||
conv_w_flat = conv_weights.reshape(-1, 4) if conv_weights.ndim == 3 else conv_weights
|
||||
|
||||
# Flatten x to [B, K]
|
||||
x_flat = x.reshape(B, K)
|
||||
|
||||
results = kern(
|
||||
inputs=[
|
||||
x_flat,
|
||||
W_merged, S_merged, B_merged,
|
||||
conv_state, conv_w_flat,
|
||||
A_log, dt_bias,
|
||||
mx.array(K, dtype=mx.int32),
|
||||
mx.array(N_QKV, dtype=mx.int32),
|
||||
mx.array(N_Z, dtype=mx.int32),
|
||||
mx.array(N_B, dtype=mx.int32),
|
||||
mx.array(N_TOTAL, dtype=mx.int32),
|
||||
mx.array(N_QKV_TG, dtype=mx.int32),
|
||||
mx.array(N_Z_TG, dtype=mx.int32),
|
||||
mx.array(N_B_TG, dtype=mx.int32),
|
||||
],
|
||||
output_shapes=[
|
||||
(B * N_QKV,), # qkv_out
|
||||
(B * N_Z,), # z_silu_out
|
||||
(B * N_B,), # beta_out (f32)
|
||||
(B * N_A,), # g_out (f32)
|
||||
(B * 3 * N_QKV,), # conv_state_out
|
||||
],
|
||||
output_dtypes=[mx.bfloat16, mx.float32, mx.float32, mx.float32, mx.bfloat16],
|
||||
grid=(32, total_tg * 2, B),
|
||||
threadgroup=(32, 2, 1),
|
||||
)
|
||||
|
||||
qkv_out = results[0].reshape(B, 1, N_QKV)
|
||||
z_silu = results[1].reshape(B, 1, N_Z)
|
||||
beta = results[2].reshape(B, 1, N_B)
|
||||
g = results[3].reshape(B, 1, N_A)
|
||||
conv_state_out = results[4].reshape(B, 3, N_QKV)
|
||||
|
||||
return qkv_out, z_silu, beta, g, conv_state_out
|
||||
@@ -0,0 +1,272 @@
|
||||
"""Fused GQA projections for Qwen3.5-35B-A3B (Dispatch 1).
|
||||
|
||||
Single dispatch fuses 4 quantized 8-bit GEMVs with region-specific epilogues:
|
||||
- q_proj queries (4096×2048): GEMV → raw bf16 write
|
||||
- q_proj gate (4096×2048): GEMV → sigmoid → f32 write
|
||||
- k_proj (512×2048): GEMV → raw bf16 write
|
||||
- v_proj (512×2048): GEMV → raw bf16 write
|
||||
|
||||
All 4 projection weight matrices are pre-merged into one contiguous buffer
|
||||
(W_merged, S_merged, B_merged) for better memory locality.
|
||||
Merging is done offline at patch time by _patch_gqa_proj_weights().
|
||||
|
||||
Gate sigmoid is computed in f32 directly from the GEMV accumulator,
|
||||
avoiding bf16 round-trip and eliminating a separate sigmoid dispatch.
|
||||
|
||||
TG-level multiplexing: tgid.y routes to different epilogues.
|
||||
Each TG: 64 threads = 2 SGs of 32, produces 8 output rows (4 per SG).
|
||||
Standard 8-bit affine GEMV: result = scale * Σ(x[i]*w[i]) + bias * Σ(x[i])
|
||||
|
||||
Grid: (32, total_tg * 2, B), TG: (32, 2, 1)
|
||||
"""
|
||||
|
||||
import mlx.core as mx
|
||||
|
||||
|
||||
def ceil_div(a, b):
|
||||
return (a + b - 1) // b
|
||||
|
||||
|
||||
def _gen_fused_gqa_projections_source(group_size=64):
|
||||
"""Generate Metal source for fused GQA projections with merged weights.
|
||||
|
||||
8-bit dequantization (group_size=64):
|
||||
result = scale * Σ(x[i]*w[i]) + bias * Σ(x[i])
|
||||
|
||||
Single merged weight buffer indexed by absolute out_row.
|
||||
TG routing via tgid.y determines region (epilogue):
|
||||
[0, N_Q_TG): Queries GEMV → raw bf16
|
||||
[N_Q_TG, +N_GATE_TG): Gate GEMV → sigmoid → f32
|
||||
[+N_GATE_TG, +N_K_TG): Keys GEMV → raw bf16
|
||||
[+N_K_TG, +N_V_TG): Values GEMV → raw bf16
|
||||
"""
|
||||
gs = int(group_size)
|
||||
sc_stride = 256 // gs # groups consumed per K-block = 4
|
||||
slid_div = gs // 8 # threads per group = 8
|
||||
|
||||
return f"""
|
||||
const int RESULTS_PER_SG = 4;
|
||||
const int VALUES_PER_THREAD = 8;
|
||||
const int BLOCK_SIZE = 256; // 32 * 8
|
||||
const int GROUP_SIZE = {gs};
|
||||
const int SC_STRIDE = {sc_stride};
|
||||
const int SLID_DIV = {slid_div};
|
||||
|
||||
int K = K_val;
|
||||
int K_groups = K / GROUP_SIZE;
|
||||
|
||||
// Dimension boundaries
|
||||
int N_Q = N_Q_val;
|
||||
int N_GATE = N_GATE_val;
|
||||
int N_K = N_K_val;
|
||||
int N_TOTAL = N_TOTAL_val;
|
||||
|
||||
// TG boundaries
|
||||
int N_Q_TG = N_Q_TG_val;
|
||||
int N_GATE_TG = N_GATE_TG_val;
|
||||
int N_K_TG = N_K_TG_val;
|
||||
|
||||
uint3 tgid = threadgroup_position_in_grid;
|
||||
uint sgid = simdgroup_index_in_threadgroup; // 0 or 1
|
||||
uint slid = thread_index_in_simdgroup; // 0..31
|
||||
int b_idx = tgid.z;
|
||||
|
||||
int tg = tgid.y;
|
||||
|
||||
// ─── Determine region and absolute out_row in merged matrix ───
|
||||
int out_row;
|
||||
int region; // 0=Q, 1=Gate, 2=K, 3=V
|
||||
|
||||
if (tg < N_Q_TG) {{
|
||||
region = 0;
|
||||
out_row = tg * 8 + sgid * RESULTS_PER_SG;
|
||||
}} else if (tg < N_Q_TG + N_GATE_TG) {{
|
||||
region = 1;
|
||||
out_row = N_Q + (tg - N_Q_TG) * 8 + sgid * RESULTS_PER_SG;
|
||||
}} else if (tg < N_Q_TG + N_GATE_TG + N_K_TG) {{
|
||||
region = 2;
|
||||
out_row = N_Q + N_GATE + (tg - N_Q_TG - N_GATE_TG) * 8 + sgid * RESULTS_PER_SG;
|
||||
}} else {{
|
||||
region = 3;
|
||||
out_row = N_Q + N_GATE + N_K + (tg - N_Q_TG - N_GATE_TG - N_K_TG) * 8 + sgid * RESULTS_PER_SG;
|
||||
}}
|
||||
|
||||
if (out_row >= N_TOTAL) return;
|
||||
|
||||
// ─── Single pointer into merged weight buffer ───
|
||||
const device uint8_t* ws = (const device uint8_t*)W_merged + (long)out_row * K + slid * VALUES_PER_THREAD;
|
||||
const device bfloat16_t* sc = (const device bfloat16_t*)S_merged + (long)out_row * K_groups + slid / SLID_DIV;
|
||||
const device bfloat16_t* bi = (const device bfloat16_t*)B_merged + (long)out_row * K_groups + slid / SLID_DIV;
|
||||
|
||||
// ─── 8-bit GEMV K-loop (unified for all regions) ───
|
||||
float result[4] = {{0, 0, 0, 0}};
|
||||
int x_base = b_idx * K + slid * VALUES_PER_THREAD;
|
||||
|
||||
for (int k_off = 0; k_off < K; k_off += BLOCK_SIZE) {{
|
||||
float x_thread[8];
|
||||
float xsum = 0;
|
||||
for (int i = 0; i < 8; i++) {{
|
||||
float xi = float(x[x_base + i]);
|
||||
x_thread[i] = xi;
|
||||
xsum += xi;
|
||||
}}
|
||||
|
||||
for (int row = 0; row < RESULTS_PER_SG; row++) {{
|
||||
const device uint8_t* w = ws + row * K;
|
||||
float s_val = float(sc[row * K_groups]);
|
||||
float b_val = float(bi[row * K_groups]);
|
||||
float accum = 0;
|
||||
for (int i = 0; i < 8; i++) {{
|
||||
accum += x_thread[i] * float(w[i]);
|
||||
}}
|
||||
result[row] += s_val * accum + xsum * b_val;
|
||||
}}
|
||||
|
||||
ws += BLOCK_SIZE;
|
||||
sc += SC_STRIDE;
|
||||
bi += SC_STRIDE;
|
||||
x_base += BLOCK_SIZE;
|
||||
}}
|
||||
|
||||
// ─── Reduction ───
|
||||
for (int row = 0; row < RESULTS_PER_SG; row++) {{
|
||||
result[row] = simd_sum(result[row]);
|
||||
}}
|
||||
|
||||
// ─── Region-specific epilogues ───
|
||||
// After simd_sum, all 32 threads have result[0..3].
|
||||
// Threads 0-3 each handle one output row.
|
||||
|
||||
if (region == 0) {{
|
||||
// ═══ Queries: raw bf16 write ═══
|
||||
int q_row = out_row + (int)slid;
|
||||
if (slid < (uint)RESULTS_PER_SG && q_row < N_Q) {{
|
||||
q_out[b_idx * N_Q + q_row] = static_cast<bfloat16_t>(result[slid]);
|
||||
}}
|
||||
|
||||
}} else if (region == 1) {{
|
||||
// ═══ Gate: sigmoid → f32 ═══
|
||||
int g_row = out_row - N_Q + (int)slid;
|
||||
if (slid < (uint)RESULTS_PER_SG && g_row < N_GATE) {{
|
||||
float val = result[slid];
|
||||
float sig = 1.0f / (1.0f + metal::exp(-val));
|
||||
gate_out[b_idx * N_GATE + g_row] = sig;
|
||||
}}
|
||||
|
||||
}} else if (region == 2) {{
|
||||
// ═══ Keys: raw bf16 write ═══
|
||||
int k_row = out_row - N_Q - N_GATE + (int)slid;
|
||||
if (slid < (uint)RESULTS_PER_SG && k_row < N_K) {{
|
||||
k_out[b_idx * N_K + k_row] = static_cast<bfloat16_t>(result[slid]);
|
||||
}}
|
||||
|
||||
}} else {{
|
||||
// ═══ Values: raw bf16 write ═══
|
||||
int v_row = out_row - N_Q - N_GATE - N_K + (int)slid;
|
||||
int N_V = N_TOTAL - N_Q - N_GATE - N_K;
|
||||
if (slid < (uint)RESULTS_PER_SG && v_row < N_V) {{
|
||||
v_out[b_idx * N_V + v_row] = static_cast<bfloat16_t>(result[slid]);
|
||||
}}
|
||||
}}
|
||||
"""
|
||||
|
||||
|
||||
_fused_gqa_proj_kernel = None
|
||||
|
||||
|
||||
def _get_fused_gqa_proj_kernel():
|
||||
"""Get or compile the fused GQA projections kernel."""
|
||||
global _fused_gqa_proj_kernel
|
||||
if _fused_gqa_proj_kernel is None:
|
||||
_fused_gqa_proj_kernel = mx.fast.metal_kernel(
|
||||
name="fused_gqa_projections_8bit_merged",
|
||||
input_names=[
|
||||
"x",
|
||||
"W_merged", "S_merged", "B_merged",
|
||||
"K_val",
|
||||
"N_Q_val", "N_GATE_val", "N_K_val", "N_TOTAL_val",
|
||||
"N_Q_TG_val", "N_GATE_TG_val", "N_K_TG_val",
|
||||
],
|
||||
output_names=["q_out", "gate_out", "k_out", "v_out"],
|
||||
source=_gen_fused_gqa_projections_source(),
|
||||
)
|
||||
return _fused_gqa_proj_kernel
|
||||
|
||||
|
||||
def fused_gqa_projections(
|
||||
x,
|
||||
W_merged, S_merged, B_merged,
|
||||
proj_dims,
|
||||
batch_size=1,
|
||||
scalars=None, total_tg=None,
|
||||
):
|
||||
"""Fused GQA projections: 4 GEMVs with region-specific epilogues.
|
||||
|
||||
Uses pre-merged contiguous weight buffers for all 4 projections.
|
||||
Gate epilogue computes sigmoid in f32 directly from GEMV accumulator.
|
||||
|
||||
Args:
|
||||
x: [B, 1, K] bf16 — post-RMSNorm hidden state
|
||||
W_merged: [N_TOTAL, K/4] uint32 — merged quantized weights
|
||||
S_merged: [N_TOTAL, K/gs] bf16 — merged scales
|
||||
B_merged: [N_TOTAL, K/gs] bf16 — merged biases
|
||||
proj_dims: (N_Q, N_GATE, N_K, N_V) — per-projection output dims
|
||||
batch_size: int
|
||||
scalars: dict of pre-cached mx.array scalars (optional, avoids per-call creation)
|
||||
total_tg: pre-computed total TG count (optional)
|
||||
|
||||
Returns:
|
||||
queries: [B, 1, N_Q] bf16
|
||||
gate_sigmoid: [B, 1, N_GATE] f32 — sigmoid(gate), ready for post-SDPA multiply
|
||||
keys: [B, 1, N_K] bf16
|
||||
values: [B, 1, N_V] bf16
|
||||
"""
|
||||
B = batch_size
|
||||
kern = _get_fused_gqa_proj_kernel()
|
||||
|
||||
N_Q, N_GATE, N_K, N_V = proj_dims
|
||||
K = x.shape[-1]
|
||||
|
||||
# Flatten x to [B, K]
|
||||
x_flat = x.reshape(B, K)
|
||||
|
||||
if scalars is not None:
|
||||
s = scalars
|
||||
inputs = [x_flat, W_merged, S_merged, B_merged,
|
||||
s['K'], s['N_Q'], s['N_GATE'], s['N_K'], s['N_TOTAL'],
|
||||
s['N_Q_TG'], s['N_GATE_TG'], s['N_K_TG']]
|
||||
else:
|
||||
N_TOTAL = N_Q + N_GATE + N_K + N_V
|
||||
total_tg = ceil_div(N_Q, 8) + ceil_div(N_GATE, 8) + ceil_div(N_K, 8) + ceil_div(N_V, 8)
|
||||
inputs = [x_flat, W_merged, S_merged, B_merged,
|
||||
mx.array(K, dtype=mx.int32),
|
||||
mx.array(N_Q, dtype=mx.int32),
|
||||
mx.array(N_GATE, dtype=mx.int32),
|
||||
mx.array(N_K, dtype=mx.int32),
|
||||
mx.array(N_TOTAL, dtype=mx.int32),
|
||||
mx.array(ceil_div(N_Q, 8), dtype=mx.int32),
|
||||
mx.array(ceil_div(N_GATE, 8), dtype=mx.int32),
|
||||
mx.array(ceil_div(N_K, 8), dtype=mx.int32)]
|
||||
|
||||
if total_tg is None:
|
||||
total_tg = ceil_div(N_Q, 8) + ceil_div(N_GATE, 8) + ceil_div(N_K, 8) + ceil_div(N_V, 8)
|
||||
|
||||
results = kern(
|
||||
inputs=inputs,
|
||||
output_shapes=[
|
||||
(B * N_Q,), # q_out
|
||||
(B * N_GATE,), # gate_out (f32)
|
||||
(B * N_K,), # k_out
|
||||
(B * N_V,), # v_out
|
||||
],
|
||||
output_dtypes=[mx.bfloat16, mx.float32, mx.bfloat16, mx.bfloat16],
|
||||
grid=(32, total_tg * 2, B),
|
||||
threadgroup=(32, 2, 1),
|
||||
)
|
||||
|
||||
queries = results[0].reshape(B, 1, N_Q)
|
||||
gate_sigmoid = results[1].reshape(B, 1, N_GATE)
|
||||
keys = results[2].reshape(B, 1, N_K)
|
||||
values = results[3].reshape(B, 1, N_V)
|
||||
|
||||
return queries, gate_sigmoid, keys, values
|
||||
@@ -0,0 +1,201 @@
|
||||
"""Fused Q/K RMSNorm + RoPE for GQA attention (Dispatch 2).
|
||||
|
||||
Performs per-head RMSNorm with learned weight (head_dim=256) then applies
|
||||
RoPE on the first 64 dims (partial_rotary_factor=0.25) using non-traditional
|
||||
pairing: element p pairs with p+32 (not p+1).
|
||||
|
||||
RMSNorm with weight:
|
||||
inv_rms = rsqrt(mean(x^2) + eps) = rsqrt(sum(x^2)/D + eps)
|
||||
out[i] = x[i] * inv_rms * weight[i]
|
||||
|
||||
RoPE (non-traditional, partial):
|
||||
Pairs (p, p+32) for p in {0, ..., 31}:
|
||||
x'[p] = x[p]*cos(m*f_p) - x[p+32]*sin(m*f_p)
|
||||
x'[p+32] = x[p]*sin(m*f_p) + x[p+32]*cos(m*f_p)
|
||||
where f_p = theta^(-p/32), m = cache position
|
||||
Only first 64 of 256 dims rotated; remaining 192 unchanged.
|
||||
|
||||
Grid: ((H_q + H_kv) * 32, 1, B)
|
||||
Each TG = 32 threads = 1 SG, handles one 256-dim head.
|
||||
D=256 = 32 threads x 8 elements -> exactly 1 SG, no cross-SG reduction.
|
||||
"""
|
||||
|
||||
import mlx.core as mx
|
||||
|
||||
|
||||
def _gen_fused_qk_norm_rope_source(H_q=16, H_kv=2, D=256, rope_dims=64):
|
||||
"""Generate Metal source for fused Q/K RMSNorm + RoPE.
|
||||
|
||||
Input: queries [B, H_q*D] bf16, keys [B, H_kv*D] bf16
|
||||
Output: q_out [B, H_q*D] bf16, k_out [B, H_kv*D] bf16
|
||||
|
||||
TG assignment:
|
||||
tgid.x 0..H_q-1: Q heads
|
||||
tgid.x H_q..H_q+H_kv-1: K heads
|
||||
|
||||
Thread layout (32 threads, N_READS=8):
|
||||
Thread t handles elements [8t, 8t+7]
|
||||
|
||||
RoPE thread assignment (non-traditional pairing):
|
||||
Threads 0-3: first half of pair (elements 0-31)
|
||||
Threads 4-7: second half of pair (elements 32-63)
|
||||
Thread t paired with t^4 via simd_shuffle
|
||||
Threads 8-31: elements 64-255 (unrotated, skip RoPE)
|
||||
"""
|
||||
N_READS = D // 32
|
||||
ROPE_HALF = rope_dims // 2 # 32 = number of rotation pairs
|
||||
ROPE_THREADS = rope_dims // N_READS # 8 = threads touching rotated dims
|
||||
FIRST_HALF = ROPE_THREADS // 2 # 4 = threads in first half of pairs
|
||||
PARTNER_XOR = FIRST_HALF # 4 = XOR to find partner thread
|
||||
|
||||
return f"""
|
||||
// ── Constants ──
|
||||
const int H_Q = {H_q};
|
||||
const int H_KV = {H_kv};
|
||||
const int D_DIM = {D};
|
||||
const int N_READS = {N_READS};
|
||||
const float EPS = 1e-6f;
|
||||
|
||||
uint head_idx = threadgroup_position_in_grid.x;
|
||||
uint slid = thread_index_in_simdgroup;
|
||||
uint b_idx = thread_position_in_grid.z;
|
||||
|
||||
bool is_q = (head_idx < (uint)H_Q);
|
||||
int head_local = is_q ? (int)head_idx : ((int)head_idx - H_Q);
|
||||
|
||||
// ── Phase 1: Load N_READS elements + partial sum of squares ──
|
||||
int in_base = is_q
|
||||
? (int)(b_idx * H_Q * D_DIM + (int)head_idx * D_DIM)
|
||||
: (int)(b_idx * H_KV * D_DIM + head_local * D_DIM);
|
||||
|
||||
int elem_base = (int)slid * N_READS;
|
||||
float vals[{N_READS}];
|
||||
float partial_sq = 0.0f;
|
||||
|
||||
for (int i = 0; i < N_READS; i++) {{
|
||||
float xi;
|
||||
if (is_q)
|
||||
xi = (float)queries[in_base + elem_base + i];
|
||||
else
|
||||
xi = (float)keys[in_base + elem_base + i];
|
||||
vals[i] = xi;
|
||||
partial_sq += xi * xi;
|
||||
}}
|
||||
|
||||
// ── Phase 2: RMSNorm reduction (32 threads -> full sum of {D} elements) ──
|
||||
float sum_sq = simd_sum(partial_sq);
|
||||
float inv_rms = metal::precise::rsqrt(sum_sq / (float)D_DIM + EPS);
|
||||
|
||||
// ── Phase 3: Normalize with learned weight ──
|
||||
for (int i = 0; i < N_READS; i++) {{
|
||||
float w;
|
||||
if (is_q)
|
||||
w = (float)q_norm_w[elem_base + i];
|
||||
else
|
||||
w = (float)k_norm_w[elem_base + i];
|
||||
vals[i] = vals[i] * inv_rms * w;
|
||||
}}
|
||||
|
||||
// ── Phase 4: RoPE on first {rope_dims} dims (threads 0..{ROPE_THREADS - 1}) ──
|
||||
if (slid < {ROPE_THREADS}u) {{
|
||||
ushort partner = (ushort)(slid ^ {PARTNER_XOR}u);
|
||||
int cos_base = (int)(slid & {FIRST_HALF - 1}u) * N_READS;
|
||||
|
||||
// Compute cos/sin on-device from precomputed inv_freq
|
||||
// angle = position * inv_freq[d], where inv_freq[d] = theta^(-d/{ROPE_HALF})
|
||||
float cos_arr[{N_READS}], sin_arr[{N_READS}];
|
||||
for (int i = 0; i < N_READS; i++) {{
|
||||
float angle = (float)position[0] * inv_freq[cos_base + i];
|
||||
cos_arr[i] = metal::fast::cos(angle);
|
||||
sin_arr[i] = metal::fast::sin(angle);
|
||||
}}
|
||||
|
||||
// Exchange normalized values with partner thread via simd_shuffle
|
||||
float partner_vals[{N_READS}];
|
||||
for (int i = 0; i < N_READS; i++)
|
||||
partner_vals[i] = simd_shuffle(vals[i], partner);
|
||||
|
||||
if (slid < {FIRST_HALF}u) {{
|
||||
// First half of pair: x'[p] = x[p]*cos - x[p+{ROPE_HALF}]*sin
|
||||
for (int i = 0; i < N_READS; i++)
|
||||
vals[i] = vals[i] * cos_arr[i] - partner_vals[i] * sin_arr[i];
|
||||
}} else {{
|
||||
// Second half: x'[p+{ROPE_HALF}] = x_first*sin + x[p+{ROPE_HALF}]*cos
|
||||
for (int i = 0; i < N_READS; i++)
|
||||
vals[i] = partner_vals[i] * sin_arr[i] + vals[i] * cos_arr[i];
|
||||
}}
|
||||
}}
|
||||
|
||||
// ── Phase 5: Write output ──
|
||||
int out_base = is_q
|
||||
? (int)(b_idx * H_Q * D_DIM + (int)head_idx * D_DIM)
|
||||
: (int)(b_idx * H_KV * D_DIM + head_local * D_DIM);
|
||||
|
||||
for (int i = 0; i < N_READS; i++) {{
|
||||
if (is_q)
|
||||
q_out[out_base + elem_base + i] = static_cast<bfloat16_t>(vals[i]);
|
||||
else
|
||||
k_out[out_base + elem_base + i] = static_cast<bfloat16_t>(vals[i]);
|
||||
}}
|
||||
"""
|
||||
|
||||
|
||||
_kernel_cache = {}
|
||||
|
||||
|
||||
def _get_kernel(H_q, H_kv, D, rope_dims):
|
||||
"""Get or compile the fused Q/K RMSNorm + RoPE kernel."""
|
||||
key = (H_q, H_kv, D, rope_dims)
|
||||
if key not in _kernel_cache:
|
||||
_kernel_cache[key] = mx.fast.metal_kernel(
|
||||
name="fused_qk_norm_rope",
|
||||
input_names=["queries", "keys", "q_norm_w", "k_norm_w",
|
||||
"inv_freq", "position"],
|
||||
output_names=["q_out", "k_out"],
|
||||
source=_gen_fused_qk_norm_rope_source(H_q, H_kv, D, rope_dims),
|
||||
)
|
||||
return _kernel_cache[key]
|
||||
|
||||
|
||||
def fused_qk_norm_rope(queries, keys, q_norm_weight, k_norm_weight,
|
||||
inv_freq, cache_offset, H_q, H_kv, D,
|
||||
batch_size=1):
|
||||
"""Fused Q/K per-head RMSNorm + RoPE for GQA attention.
|
||||
|
||||
Args:
|
||||
queries: [B, 1, H_q*D] bf16 — raw queries from Dispatch 1.
|
||||
keys: [B, 1, H_kv*D] bf16 — raw keys from Dispatch 1.
|
||||
q_norm_weight: [D] bf16 — RMSNorm learned weight for queries.
|
||||
k_norm_weight: [D] bf16 — RMSNorm learned weight for keys.
|
||||
inv_freq: [rope_dims/2] f32 — precomputed theta^(-d/half_dims).
|
||||
cache_offset: int — sequence position for RoPE angles.
|
||||
H_q: int — number of query heads.
|
||||
H_kv: int — number of key/value heads.
|
||||
D: int — head dimension.
|
||||
batch_size: int — batch size.
|
||||
|
||||
Returns:
|
||||
q_normed_roped: [B, H_q, 1, D] bf16 — ready for SDPA.
|
||||
k_normed_roped: [B, H_kv, 1, D] bf16 — ready for cache update.
|
||||
"""
|
||||
B = batch_size
|
||||
rope_dims = inv_freq.shape[0] * 2
|
||||
|
||||
kern = _get_kernel(H_q, H_kv, D, rope_dims)
|
||||
|
||||
q_flat = queries.reshape(B, H_q * D)
|
||||
k_flat = keys.reshape(B, H_kv * D)
|
||||
pos = mx.array(cache_offset, dtype=mx.int32)
|
||||
|
||||
n_heads = H_q + H_kv
|
||||
results = kern(
|
||||
inputs=[q_flat, k_flat, q_norm_weight, k_norm_weight, inv_freq, pos],
|
||||
output_shapes=[(B * H_q * D,), (B * H_kv * D,)],
|
||||
output_dtypes=[mx.bfloat16, mx.bfloat16],
|
||||
grid=(n_heads * 32, 1, B),
|
||||
threadgroup=(32, 1, 1),
|
||||
)
|
||||
|
||||
q_out = results[0].reshape(B, H_q, 1, D)
|
||||
k_out = results[1].reshape(B, H_kv, 1, D)
|
||||
return q_out, k_out
|
||||
@@ -0,0 +1,128 @@
|
||||
"""Fused Q/K per-head L2-norm for GDN attention (Dispatch 3).
|
||||
|
||||
Performs per-head L2 normalization on q and k vectors with different scaling.
|
||||
Matches vLLM and latest mlx-lm (qwen3_5.py) which use rsqrt(sum(x²) + eps),
|
||||
NOT rms_norm which uses rsqrt(mean(x²) + eps).
|
||||
|
||||
From qwen3_5.py (updated to match vLLM):
|
||||
inv_scale = Dk^(-0.5) = 128^(-0.5)
|
||||
q = inv_scale * q * rsqrt(sum(q²) + 1e-6) → L2-normalize then scale by 1/√Dk
|
||||
k = k * rsqrt(sum(k²) + 1e-6) → L2-normalize only (no extra scale)
|
||||
|
||||
Grid: (32 heads × 32 threads, 1, B).
|
||||
Each TG = 32 threads = 1 SG, handles one 128-dim head.
|
||||
Dk=128 = 32 threads × 4 elements → exactly 1 SG, no cross-SG reduction.
|
||||
"""
|
||||
|
||||
import mlx.core as mx
|
||||
|
||||
|
||||
def _gen_fused_qk_rmsnorm_source():
|
||||
"""Generate Metal source for fused Q/K per-head L2-norm.
|
||||
|
||||
Input: qkv [B, 8192] bf16 (flattened from [B, 1, 8192])
|
||||
- [0, 2048): q = 16 heads × 128
|
||||
- [2048, 4096): k = 16 heads × 128
|
||||
- [4096, 8192): v (untouched)
|
||||
|
||||
Output: qk_out [B, 4096] bf16
|
||||
- [0, 2048): q L2-normalized then scaled by 1/√Dk
|
||||
- [2048, 4096): k L2-normalized (no extra scale)
|
||||
|
||||
Grid: (32 * 32, 1, B), TG: (32, 1, 1)
|
||||
tgid.x 0..15: q heads → scale = 1/√128
|
||||
tgid.x 16..31: k heads → scale = 1.0
|
||||
tgid.z: batch index
|
||||
"""
|
||||
return """
|
||||
const int N_READS = 4;
|
||||
const int DK = 128;
|
||||
const int HK = 16;
|
||||
const float EPS = 1e-6f;
|
||||
const float Q_SCALE = rsqrt(128.0f); // inv_scale = Dk^(-0.5)
|
||||
const float K_SCALE = 1.0f; // no extra scale for k
|
||||
|
||||
uint head_idx = threadgroup_position_in_grid.x;
|
||||
uint slid = thread_index_in_simdgroup;
|
||||
uint b_idx = thread_position_in_grid.z;
|
||||
|
||||
bool is_q = (head_idx < (uint)HK);
|
||||
|
||||
// Input offset: q heads at [0, 2048), k heads at [2048, 4096)
|
||||
int in_base = is_q
|
||||
? (b_idx * 8192 + head_idx * DK)
|
||||
: (b_idx * 8192 + 2048 + (head_idx - HK) * DK);
|
||||
|
||||
// Output offset: q at [0, 2048), k at [2048, 4096)
|
||||
int out_base = b_idx * 4096 + head_idx * DK;
|
||||
|
||||
// ── Phase 1: Load 4 elements + sum of squares ──
|
||||
float vals[4];
|
||||
float partial_sq = 0.0f;
|
||||
int elem_base = slid * N_READS;
|
||||
|
||||
for (int i = 0; i < N_READS; i++) {
|
||||
float xi = float(qkv[in_base + elem_base + i]);
|
||||
vals[i] = xi;
|
||||
partial_sq += xi * xi;
|
||||
}
|
||||
|
||||
// ── Phase 2: simd reduction (32 threads → full sum of 128 elements) ──
|
||||
float sum_sq = simd_sum(partial_sq);
|
||||
|
||||
// ── Phase 3: compute L2 inv-norm (NOT rms_norm — no /Dk) ──
|
||||
float inv_rms = metal::precise::rsqrt(sum_sq + EPS);
|
||||
|
||||
// ── Phase 4: scale and write ──
|
||||
float scale = is_q ? Q_SCALE : K_SCALE;
|
||||
float combined = inv_rms * scale;
|
||||
|
||||
for (int i = 0; i < N_READS; i++) {
|
||||
qk_out[out_base + elem_base + i] = static_cast<bfloat16_t>(vals[i] * combined);
|
||||
}
|
||||
"""
|
||||
|
||||
|
||||
_fused_qk_rmsnorm_kernel = None
|
||||
|
||||
|
||||
def _get_fused_qk_rmsnorm_kernel():
|
||||
"""Get or compile the fused Q/K RMSNorm kernel."""
|
||||
global _fused_qk_rmsnorm_kernel
|
||||
if _fused_qk_rmsnorm_kernel is None:
|
||||
_fused_qk_rmsnorm_kernel = mx.fast.metal_kernel(
|
||||
name="fused_qk_rmsnorm",
|
||||
input_names=["qkv"],
|
||||
output_names=["qk_out"],
|
||||
source=_gen_fused_qk_rmsnorm_source(),
|
||||
)
|
||||
return _fused_qk_rmsnorm_kernel
|
||||
|
||||
|
||||
def fused_qk_rmsnorm(qkv_conv_silu, batch_size=1):
|
||||
"""Fused Q/K per-head RMSNorm for GDN attention.
|
||||
|
||||
Args:
|
||||
qkv_conv_silu: [B, 1, 8192] bf16 — post-conv, post-SiLU output from Dispatch 2.
|
||||
First 2048 = q (16 heads × 128), next 2048 = k, last 4096 = v.
|
||||
batch_size: int — batch dimension.
|
||||
|
||||
Returns:
|
||||
qk_normed: [B, 1, 4096] bf16 — normalized q (first 2048) and k (next 2048).
|
||||
v is NOT copied; Dispatch 4 reads v directly from qkv_conv_silu[:, :, 4096:].
|
||||
"""
|
||||
B = batch_size
|
||||
kern = _get_fused_qk_rmsnorm_kernel()
|
||||
|
||||
# Flatten to [B, 8192] for kernel
|
||||
qkv_flat = qkv_conv_silu.reshape(B, 8192)
|
||||
|
||||
n_heads = 32 # 16 q + 16 k
|
||||
results = kern(
|
||||
inputs=[qkv_flat],
|
||||
output_shapes=[(B * 4096,)],
|
||||
output_dtypes=[mx.bfloat16],
|
||||
grid=(n_heads * 32, 1, B),
|
||||
threadgroup=(32, 1, 1),
|
||||
)
|
||||
return results[0].reshape(B, 1, 4096)
|
||||
@@ -0,0 +1,117 @@
|
||||
"""Fused RMSNormGated for GDN attention (Dispatch 5).
|
||||
|
||||
Fuses RMSNorm(out, weight) × z_silu into one kernel.
|
||||
SiLU on z was already applied in Dispatch 2, so z_silu arrives as f32.
|
||||
|
||||
From qwen3_next.py (Qwen3NextRMSNormGated):
|
||||
x = rms_norm(hidden_states, weight, eps) # weight: [Dv=128]
|
||||
gate = silu(z.float()) # already done in Dispatch 2
|
||||
return (gate * x).to(hidden_states.dtype)
|
||||
|
||||
Grid: (32 heads × 32 threads, 1, B).
|
||||
Each TG = 32 threads = 1 SG, handles one 128-dim head.
|
||||
Dv=128 = 32 threads × 4 elements → exactly 1 SG.
|
||||
"""
|
||||
|
||||
import mlx.core as mx
|
||||
|
||||
|
||||
def _gen_fused_rms_norm_gated_source():
|
||||
"""Generate Metal source for fused RMSNormGated.
|
||||
|
||||
Inputs:
|
||||
gdn_out: [B, Hv*Dv] bf16 — GDN output, flattened (Hv=32, Dv=128)
|
||||
z_silu: [B, Hv*Dv] f32 — post-SiLU z from Dispatch 2
|
||||
weight: [Dv] f32 — RMSNormGated learned weight (128 elements)
|
||||
|
||||
Output:
|
||||
out: [B, Hv*Dv] bf16 — result = z_silu * rms_norm(gdn_out, weight)
|
||||
|
||||
Grid: (32 * 32, 1, B), TG: (32, 1, 1)
|
||||
tgid.x: head index (0..31)
|
||||
tgid.z: batch index
|
||||
"""
|
||||
return """
|
||||
const int N_READS = 4;
|
||||
const int DV = 128;
|
||||
const int HV = 32;
|
||||
const float EPS = 1e-6f;
|
||||
|
||||
uint head_idx = threadgroup_position_in_grid.x;
|
||||
uint slid = thread_index_in_simdgroup;
|
||||
uint b_idx = thread_position_in_grid.z;
|
||||
|
||||
int base = b_idx * HV * DV + head_idx * DV;
|
||||
int elem_base = slid * N_READS;
|
||||
|
||||
// ── Phase 1: Load gdn_out elements + sum of squares ──
|
||||
float gdn_vals[4];
|
||||
float partial_sq = 0.0f;
|
||||
|
||||
for (int i = 0; i < N_READS; i++) {
|
||||
float xi = float(gdn_out[base + elem_base + i]);
|
||||
gdn_vals[i] = xi;
|
||||
partial_sq += xi * xi;
|
||||
}
|
||||
|
||||
// ── Phase 2: simd reduction (32 threads → full sum of 128 elements) ──
|
||||
float sum_sq = simd_sum(partial_sq);
|
||||
|
||||
// ── Phase 3: compute inv_rms ──
|
||||
float inv_rms = metal::precise::rsqrt(sum_sq / float(DV) + EPS);
|
||||
|
||||
// ── Phase 4: RMSNorm × z_silu, write bf16 ──
|
||||
for (int i = 0; i < N_READS; i++) {
|
||||
int idx = elem_base + i;
|
||||
float w = float(weight[idx]); // learned weight[Dv]
|
||||
float normed = gdn_vals[i] * inv_rms * w; // RMSNorm
|
||||
float z_val = z_silu[base + idx]; // already f32, post-SiLU
|
||||
out[base + idx] = static_cast<bfloat16_t>(z_val * normed);
|
||||
}
|
||||
"""
|
||||
|
||||
|
||||
_fused_rms_norm_gated_kernel = None
|
||||
|
||||
|
||||
def _get_fused_rms_norm_gated_kernel():
|
||||
"""Get or compile the fused RMSNormGated kernel."""
|
||||
global _fused_rms_norm_gated_kernel
|
||||
if _fused_rms_norm_gated_kernel is None:
|
||||
_fused_rms_norm_gated_kernel = mx.fast.metal_kernel(
|
||||
name="fused_rms_norm_gated",
|
||||
input_names=["gdn_out", "z_silu", "weight"],
|
||||
output_names=["out"],
|
||||
source=_gen_fused_rms_norm_gated_source(),
|
||||
)
|
||||
return _fused_rms_norm_gated_kernel
|
||||
|
||||
|
||||
def fused_rms_norm_gated(gdn_out, z_silu, weight, batch_size=1):
|
||||
"""Fused RMSNormGated: RMSNorm(out, weight) × z_silu.
|
||||
|
||||
Args:
|
||||
gdn_out: [B, 1, Hv, Dv] bf16 — GDN recurrence output (Hv=32, Dv=128).
|
||||
z_silu: [B, 1, 4096] f32 — post-SiLU z from Dispatch 2.
|
||||
weight: [128] f32 — RMSNormGated learned weight (Dv elements).
|
||||
batch_size: int.
|
||||
|
||||
Returns:
|
||||
out: [B, 1, 4096] bf16 — ready for out_proj in Dispatch 6.
|
||||
"""
|
||||
B = batch_size
|
||||
kern = _get_fused_rms_norm_gated_kernel()
|
||||
|
||||
# Flatten to [B, 4096]
|
||||
gdn_flat = gdn_out.reshape(B, 4096)
|
||||
z_flat = z_silu.reshape(B, 4096)
|
||||
|
||||
n_heads = 32 # Hv
|
||||
results = kern(
|
||||
inputs=[gdn_flat, z_flat, weight],
|
||||
output_shapes=[(B * 4096,)],
|
||||
output_dtypes=[mx.bfloat16],
|
||||
grid=(n_heads * 32, 1, B),
|
||||
threadgroup=(32, 1, 1),
|
||||
)
|
||||
return results[0].reshape(B, 1, 4096)
|
||||
@@ -0,0 +1,177 @@
|
||||
"""GDN recurrence with pre-computed g and beta (Dispatch 4).
|
||||
|
||||
Modified version of gated_delta_step from mlx-lm-fork/mlx_lm/models/gated_delta.py.
|
||||
Instead of computing g = exp(-exp(A_log) * softplus(a + dt_bias)) and beta = sigmoid(b)
|
||||
inside the kernel, accepts them as pre-computed f32 inputs from Dispatch 2.
|
||||
|
||||
Non-vectorized only (Qwen3.5-35B-A3B uses scalar gating per head).
|
||||
|
||||
Grid: (32, Dv, B*Hv) = (32, 128, B*32), TG: (32, 4, 1)
|
||||
"""
|
||||
|
||||
from typing import Optional, Tuple
|
||||
|
||||
import mlx.core as mx
|
||||
|
||||
|
||||
def _make_gdn_precomputed_kernel(has_mask=False):
|
||||
"""Build the GDN kernel with pre-computed g and beta."""
|
||||
if not mx.metal.is_available():
|
||||
return None
|
||||
|
||||
mask_source = "mask[b_idx * T + t]" if has_mask else "true"
|
||||
|
||||
source = f"""
|
||||
auto n = thread_position_in_grid.z;
|
||||
auto b_idx = n / Hv;
|
||||
auto hv_idx = n % Hv;
|
||||
auto hk_idx = hv_idx / (Hv / Hk);
|
||||
constexpr int n_per_t = Dk / 32;
|
||||
|
||||
// q, k: [B, T, Hk, Dk]
|
||||
auto q_ = q + b_idx * T * Hk * Dk + hk_idx * Dk;
|
||||
auto k_ = k + b_idx * T * Hk * Dk + hk_idx * Dk;
|
||||
|
||||
// v, y: [B, T, Hv, Dv]
|
||||
auto v_ = v + b_idx * T * Hv * Dv + hv_idx * Dv;
|
||||
y += b_idx * T * Hv * Dv + hv_idx * Dv;
|
||||
|
||||
auto dk_idx = thread_position_in_threadgroup.x;
|
||||
auto dv_idx = thread_position_in_grid.y;
|
||||
|
||||
// state_in, state_out: [B, Hv, Dv, Dk]
|
||||
auto i_state = state_in + (n * Dv + dv_idx) * Dk;
|
||||
auto o_state = state_out + (n * Dv + dv_idx) * Dk;
|
||||
|
||||
float state[n_per_t];
|
||||
for (int i = 0; i < n_per_t; ++i) {{
|
||||
auto s_idx = n_per_t * dk_idx + i;
|
||||
state[i] = static_cast<float>(i_state[s_idx]);
|
||||
}}
|
||||
|
||||
// g: [B, T, Hv] f32 — pre-computed decay gate
|
||||
auto g_ = g + b_idx * T * Hv;
|
||||
// beta: [B, T, Hv] f32 — pre-computed sigmoid(b)
|
||||
auto beta_ = beta + b_idx * T * Hv;
|
||||
|
||||
for (int t = 0; t < T; ++t) {{
|
||||
if ({mask_source}) {{
|
||||
// Pre-computed g and beta (no softplus/exp/sigmoid needed)
|
||||
float g_val = g_[hv_idx];
|
||||
float beta_val = beta_[hv_idx];
|
||||
|
||||
float kv_mem = 0.0f;
|
||||
for (int i = 0; i < n_per_t; ++i) {{
|
||||
auto s_idx = n_per_t * dk_idx + i;
|
||||
state[i] = state[i] * g_val;
|
||||
kv_mem += state[i] * k_[s_idx];
|
||||
}}
|
||||
kv_mem = simd_sum(kv_mem);
|
||||
|
||||
auto delta = (v_[dv_idx] - kv_mem) * beta_val;
|
||||
|
||||
float out = 0.0f;
|
||||
for (int i = 0; i < n_per_t; ++i) {{
|
||||
auto s_idx = n_per_t * dk_idx + i;
|
||||
state[i] = state[i] + k_[s_idx] * delta;
|
||||
out += state[i] * q_[s_idx];
|
||||
}}
|
||||
out = simd_sum(out);
|
||||
if (thread_index_in_simdgroup == 0) {{
|
||||
y[dv_idx] = static_cast<InT>(out);
|
||||
}}
|
||||
}}
|
||||
// Increment data pointers to next time step
|
||||
q_ += Hk * Dk;
|
||||
k_ += Hk * Dk;
|
||||
v_ += Hv * Dv;
|
||||
y += Hv * Dv;
|
||||
g_ += Hv;
|
||||
beta_ += Hv;
|
||||
}}
|
||||
for (int i = 0; i < n_per_t; ++i) {{
|
||||
auto s_idx = n_per_t * dk_idx + i;
|
||||
o_state[s_idx] = static_cast<InT>(state[i]);
|
||||
}}
|
||||
"""
|
||||
|
||||
inputs = ["q", "k", "v", "g", "beta", "state_in", "T"]
|
||||
if has_mask:
|
||||
inputs.append("mask")
|
||||
|
||||
suffix = "_precomputed"
|
||||
if has_mask:
|
||||
suffix += "_mask"
|
||||
|
||||
return mx.fast.metal_kernel(
|
||||
name=f"gated_delta_step{suffix}",
|
||||
input_names=inputs,
|
||||
output_names=["y", "state_out"],
|
||||
source=source,
|
||||
)
|
||||
|
||||
|
||||
_gdn_precomputed_kernel = None
|
||||
_gdn_precomputed_kernel_masked = None
|
||||
|
||||
|
||||
def _get_gdn_precomputed_kernel(has_mask=False):
|
||||
"""Get or compile the pre-computed GDN kernel."""
|
||||
global _gdn_precomputed_kernel, _gdn_precomputed_kernel_masked
|
||||
if has_mask:
|
||||
if _gdn_precomputed_kernel_masked is None:
|
||||
_gdn_precomputed_kernel_masked = _make_gdn_precomputed_kernel(has_mask=True)
|
||||
return _gdn_precomputed_kernel_masked
|
||||
else:
|
||||
if _gdn_precomputed_kernel is None:
|
||||
_gdn_precomputed_kernel = _make_gdn_precomputed_kernel(has_mask=False)
|
||||
return _gdn_precomputed_kernel
|
||||
|
||||
|
||||
def gated_delta_update_precomputed(
|
||||
q: mx.array,
|
||||
k: mx.array,
|
||||
v: mx.array,
|
||||
g: mx.array,
|
||||
beta: mx.array,
|
||||
state: mx.array,
|
||||
mask: Optional[mx.array] = None,
|
||||
) -> Tuple[mx.array, mx.array]:
|
||||
"""GDN recurrence with pre-computed g and beta.
|
||||
|
||||
Args:
|
||||
q: [B, T, Hk, Dk] bf16 — normalized q from Dispatch 3
|
||||
k: [B, T, Hk, Dk] bf16 — normalized k from Dispatch 3
|
||||
v: [B, T, Hv, Dv] bf16 — v from Dispatch 2 (qkv_conv_silu[:, :, 4096:])
|
||||
g: [B, T, Hv] f32 — pre-computed decay gate from Dispatch 2
|
||||
beta: [B, T, Hv] f32 — pre-computed sigmoid(b) from Dispatch 2
|
||||
state: [B, Hv, Dv, Dk] bf16 — recurrent state from cache
|
||||
mask: [B, T] optional
|
||||
|
||||
Returns:
|
||||
y: [B, T, Hv, Dv] bf16
|
||||
new_state: [B, Hv, Dv, Dk] bf16
|
||||
"""
|
||||
B, T, Hk, Dk = k.shape
|
||||
Hv, Dv = v.shape[2:]
|
||||
input_type = q.dtype
|
||||
|
||||
kernel = _get_gdn_precomputed_kernel(has_mask=mask is not None)
|
||||
inputs = [q, k, v, g, beta, state, T]
|
||||
if mask is not None:
|
||||
inputs.append(mask)
|
||||
|
||||
return kernel(
|
||||
inputs=inputs,
|
||||
template=[
|
||||
("InT", input_type),
|
||||
("Dk", Dk),
|
||||
("Dv", Dv),
|
||||
("Hk", Hk),
|
||||
("Hv", Hv),
|
||||
],
|
||||
grid=(32, Dv, B * Hv),
|
||||
threadgroup=(32, 4, 1),
|
||||
output_shapes=[(B, T, Hv, Dv), state.shape],
|
||||
output_dtypes=[input_type, input_type],
|
||||
)
|
||||
Reference in New Issue
Block a user