enable_kv_cache_reuse don't work on Qwen L40

[yeshihai]

@yeshihai could you follow this guide to do your experiment?

Originally posted by @dominicshanshan in #2894

I followed the guide to conduct my experiment, but it didn't seem to work as expected. I initially set up everything according to the documentation. I understand you suggested checking the setup once more, which I did, but the issue persists. Could you kindly point out if there is anything I might have overlooked? I have tried to adhere to the instructions as closely as possible. Thank you for your assistance.

[ming-wei]

Does Qwen L40 use alternating sliding window attention (alternating between full attention layers and sliding window layers)?

If yes, this issue may be related to #2912. Please check #2912 (comment).