I'll continue reviewing this, but here's some feedback on the first two
patches:
v2-0001-aio-Add-some-error-checking-around-pinning.patch:
I wonder if the extra assertion in LockBufHdr() is worth the overhead.
It won't add anything without assertions, of course, but still. No
objections if you think it's worth it.
v2-0002-hio-Release-extension-lock-before-initializing-pa.patch:
Looks as far as it goes. It's a bit silly that we use RBM_ZERO_AND_LOCK,
which zeroes the page, and then we call PageInit to zero the page again.
RBM_ZERO_AND_LOCK only zeroes the page if it wasn't in the buffer cache
previously, but with P_NEW, that is always true.
- Heikki