From ad5280255ba6e37dd11cf697bd7145d2a90213ff Mon Sep 17 00:00:00 2001
From: Wentao Ye <44945378+yewentao256@users.noreply.github.com>
Date: Thu, 6 Aug 2026 04:48:36 -0400
Subject: [PATCH] [GLM Perf] DSv32/glm use skip topk for MTP case, 2.0x kernel
 performance improvement (#50904)

---
 vllm/models/deepseek_v32/amd/rocm.py  | 7 ++++---
 vllm/models/deepseek_v32/attention.py | 6 +++---
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/vllm/models/deepseek_v32/amd/rocm.py b/vllm/models/deepseek_v32/amd/rocm.py
index b71fc9ddfc..e1abe93571 100644
--- a/vllm/models/deepseek_v32/amd/rocm.py
+++ b/vllm/models/deepseek_v32/amd/rocm.py
@@ -167,7 +167,7 @@ class DeepseekV32MLAAttention(DeepseekV32Attention):
         assert isinstance(slot_mapping, dict)
         mla_slot = slot_mapping.get(self.layer_name)
 
-        if self.indexer is not None:
+        if self.indexer is not None and not self.skip_topk:
             has_indexer = True
             indexer_k_norm_w = self.indexer.k_norm.weight
             indexer_k_norm_bias = self.indexer.k_norm.bias
@@ -222,7 +222,7 @@ class DeepseekV32MLAAttention(DeepseekV32Attention):
 
         ql_nope, q_pe = self._compute_ql_nope(q_c)
 
-        if self.indexer is not None:
+        if self.indexer is not None and not self.skip_topk:
             index_q = self.indexer.wq_b(q_c)[0]
             index_q = index_q.view(-1, self.indexer.n_head, self.indexer.head_dim)
         else:
@@ -244,7 +244,8 @@ class DeepseekV32MLAAttention(DeepseekV32Attention):
             quantize_mqa=self._fp8_kv,
         )
 
-        self._run_indexer(q_c, index_q_fp8, index_weights_out)
+        if self.indexer is not None and not self.skip_topk:
+            self._run_indexer(q_c, index_q_fp8, index_weights_out)
 
         if attn_metadata is None:
             output.zero_()
diff --git a/vllm/models/deepseek_v32/attention.py b/vllm/models/deepseek_v32/attention.py
index 79d350b1bc..705db45f59 100644
--- a/vllm/models/deepseek_v32/attention.py
+++ b/vllm/models/deepseek_v32/attention.py
@@ -372,7 +372,7 @@ class DeepseekV32Attention(MLAAttention):
         assert isinstance(slot_mapping, dict)
         mla_slot = slot_mapping.get(self.layer_name)
 
-        if self.indexer is not None:
+        if self.indexer is not None and not self.skip_topk:
             has_indexer = True
             indexer_k_norm_w = self.indexer.k_norm.weight
             indexer_k_norm_bias = self.indexer.k_norm.bias
@@ -430,7 +430,7 @@ class DeepseekV32Attention(MLAAttention):
         q_nope = q_nope.transpose(0, 1)
         ql_nope = torch.bmm(q_nope, self.W_UK_T).transpose(0, 1)
 
-        if self.indexer is not None:
+        if self.indexer is not None and not self.skip_topk:
             index_q = self.indexer.wq_b(q_c)[0]
             index_q = index_q.view(-1, self.indexer.n_head, self.indexer.head_dim)
         else:
@@ -452,7 +452,7 @@ class DeepseekV32Attention(MLAAttention):
             quantize_mqa=self._fp8_query,
         )
 
-        if self.indexer is not None:
+        if self.indexer is not None and not self.skip_topk:
             sparse_attn_indexer(
                 q_c,
                 self.indexer.k_cache.prefix,