Memory pool fix for upstream change about eagle

[xiezhq-hermann]

Motivation

#3986 made substaintial change on memory pool which breaks hierarchical cache, this PR fix the interfaces problem around it.
There are separated PRs fixing other known issues with hierarchical caching, which will be merged later:
Large TP sizes: #4082
MLA support: #4009

Modifications

Primarily interface changes.

Checklist

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