Cherry pick skinny gemms (#544)

* enable skinny gemm for bs4

Signed-off-by: charlifu <charlifu@amd.com>

* add cache to on_mi250_mi300

Signed-off-by: charlifu <charlifu@amd.com>

---------

Signed-off-by: charlifu <charlifu@amd.com>
Co-authored-by: charlifu <charlifu@amd.com>

Author: gshtras

vllm/model_executor/layers/utils.py

@@ -84,7 +84,7 @@ def rocm_unquantized_gemm(x: torch.Tensor,
     m = weight.shape[0]
     cu_count = current_platform.get_cu_count()
 
-    if m > 8 and 0 < n < 4:
+    if m > 8 and 0 < n <= 4:
         out = ops.wvSplitK(weight, x_view, cu_count)
         return out.view(*x.shape[:-1], weight.shape[0])
     elif m % 4 == 0 and n == 1 and k <= 8192:

vllm/platforms/rocm.py

@@ -104,6 +104,7 @@ def device_id_to_physical_device_id(device_id: int) -> int:
         return device_id
 
 
+@cache
 def on_mi250_mi300() -> bool:
     GPU_ARCH = torch.cuda.get_device_properties("cuda").gcnArchName
     return any(arch in GPU_ARCH for arch in ["gfx90a", "gfx942"])