Quality enhancement: Immediately interrupt execution when memory OOM

[leo-pony]

…Malloc fails

What this PR does / why we need it?

Protect the scene where the first problem occurs. The execution should be interrupted when the video memory application fails, rather than waiting until an illegal address is accessed.
Test result:

1. Exception throws normally:

Corresponding code:

2. HBM Memory malloc test case successfully:

3. extern launcher test with sleep and weakup:

Does this PR introduce any user-facing change?

NA

How was this patch tested?

NA

• vLLM version: v0.11.0
• vLLM main: vllm-project/vllm@83f478b

[github-actions]

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[gemini-code-assist]

Code Review

This pull request enhances error handling by throwing exceptions upon memory allocation failures, which is a significant improvement over returning null or printing to stderr. This makes failures explicit and prevents potential crashes down the line.

My review focuses on ensuring this new exception-based error handling is robust. I've identified a few critical issues:

• A memory leak and an unchecked malloc in my_malloc.
• Another memory leak in my_free on an error path.
• A misleading error message in my_free due to a copy-paste error.

I've provided code suggestions to address these issues. Once these are fixed, the PR will be in great shape.