Re: Fix spinlock usage in UnpinBuffer() - Mailing list pgsql-patches

From Tom Lane
Subject Re: Fix spinlock usage in UnpinBuffer()
Date
Msg-id 21361.1135799789@sss.pgh.pa.us
Whole thread Raw
In response to Fix spinlock usage in UnpinBuffer()  (Qingqing Zhou <zhouqq@cs.toronto.edu>)
Responses Re: Fix spinlock usage in UnpinBuffer()
List pgsql-patches
Qingqing Zhou <zhouqq@cs.toronto.edu> writes:
> There is no LWLock protecting the spinlock in UnpinBuffer(),

I don't believe this is necessary, and if it is necessary the patch
is wrong anyway.  Because the code uses _NoHoldoff, there won't be
any check of InterruptPending in that segment of code.  Furthermore,
any callers who don't have their own interrupt holdoff in force are
probably broken --- it's unlikely that the state of bufmgr is globally
correct if the caller of UnpinBuffer loses control.

Exactly which path of control are you worried about?

            regards, tom lane

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