[cpu][ci] Add CPU Attention Tests for Neon Backend (#30347)

Signed-off-by: Fadi Arafeh <fadi.arafeh@arm.com>

tests/kernels/attention/test_cpu_attn.py

@@ -7,7 +7,8 @@ import math
 import pytest
 import torch
 
-from vllm.platforms import current_platform
+from vllm.platforms import CpuArchEnum, current_platform
+from vllm.v1.attention.backends.cpu_attn import _get_attn_isa
 
 if not current_platform.is_cpu():
     pytest.skip("skipping CPU-only tests", allow_module_level=True)
@@ -36,6 +37,21 @@ SEQ_LENS = [  # (q_len, kv_len)
 ]
 
 
+def get_attn_isa(
+    block_size: int | None = None,
+    dtype: torch.dtype | None = None,
+):
+    if block_size and dtype:
+        return _get_attn_isa(dtype, block_size)
+    else:
+        if current_platform.get_cpu_architecture() == CpuArchEnum.ARM:
+            return "neon"
+        elif torch._C._cpu._is_amx_tile_supported():
+            return "amx"
+        else:
+            return "vec"
+
+
 # rand number generation takes too much time, cache rand tensors
 @functools.lru_cache(maxsize=128, typed=False)
 def tensor_cache(
@@ -452,6 +468,49 @@ def test_varlen_with_paged_kv_normal_vec16(
     )
 
 
+@pytest.mark.parametrize("seq_lens", SEQ_LENS)
+@pytest.mark.parametrize("num_heads", NUM_HEADS)
+@pytest.mark.parametrize("head_size", HEAD_SIZES)
+@pytest.mark.parametrize("block_size", [96, 128])
+@pytest.mark.parametrize("sliding_window", SLIDING_WINDOWS)
+@pytest.mark.parametrize("dtype", QTYPES)
+@pytest.mark.parametrize("soft_cap", [None])
+@pytest.mark.parametrize("num_blocks", NUM_BLOCKS)
+@pytest.mark.parametrize("use_alibi", [False])
+@pytest.mark.parametrize("use_sink", [False])
+@pytest.mark.parametrize("isa", ["neon"])
+@pytest.mark.skipif(
+    current_platform.get_cpu_architecture() != CpuArchEnum.ARM,
+    reason="Not an Arm CPU.",
+)
+def test_varlen_with_paged_kv_normal_neon(
+    seq_lens: list[tuple[int, int]],
+    num_heads: tuple[int, int],
+    head_size: int,
+    sliding_window: int | None,
+    dtype: torch.dtype,
+    block_size: int,
+    soft_cap: float | None,
+    num_blocks: int,
+    use_alibi: bool,
+    use_sink: bool,
+    isa: str,
+) -> None:
+    varlen_with_paged_kv(
+        seq_lens=seq_lens,
+        num_heads=num_heads,
+        head_size=head_size,
+        sliding_window=sliding_window,
+        dtype=dtype,
+        block_size=block_size,
+        soft_cap=soft_cap,
+        num_blocks=num_blocks,
+        use_alibi=use_alibi,
+        use_sink=use_sink,
+        isa=isa,
+    )
+
+
 @pytest.mark.parametrize("seq_lens", SEQ_LENS)
 @pytest.mark.parametrize("num_heads", NUM_HEADS)
 @pytest.mark.parametrize("head_size", [96])
@@ -462,9 +521,7 @@ def test_varlen_with_paged_kv_normal_vec16(
 @pytest.mark.parametrize("num_blocks", NUM_BLOCKS)
 @pytest.mark.parametrize("use_alibi", [False])
 @pytest.mark.parametrize("use_sink", [False])
-@pytest.mark.parametrize(
-    "isa", ["amx"] if torch._C._cpu._is_amx_tile_supported() else ["vec"]
-)
+@pytest.mark.parametrize("isa", [get_attn_isa()])
 def test_varlen_with_paged_kv_softcap(
     seq_lens: list[tuple[int, int]],
     num_heads: tuple[int, int],
@@ -503,9 +560,7 @@ def test_varlen_with_paged_kv_softcap(
 @pytest.mark.parametrize("num_blocks", NUM_BLOCKS)
 @pytest.mark.parametrize("use_alibi", [True])
 @pytest.mark.parametrize("use_sink", [False])
-@pytest.mark.parametrize(
-    "isa", ["amx"] if torch._C._cpu._is_amx_tile_supported() else ["vec"]
-)
+@pytest.mark.parametrize("isa", [get_attn_isa()])
 def test_varlen_with_paged_kv_alibi(
     seq_lens: list[tuple[int, int]],
     num_heads: tuple[int, int],
@@ -544,9 +599,7 @@ def test_varlen_with_paged_kv_alibi(
 @pytest.mark.parametrize("num_blocks", NUM_BLOCKS)
 @pytest.mark.parametrize("use_alibi", [False])
 @pytest.mark.parametrize("use_sink", [True])
-@pytest.mark.parametrize(
-    "isa", ["amx"] if torch._C._cpu._is_amx_tile_supported() else ["vec"]
-)
+@pytest.mark.parametrize("isa", [get_attn_isa()])
 def test_varlen_with_paged_kv_sink(
     seq_lens: list[tuple[int, int]],
     num_heads: tuple[int, int],