Re: Small code improvement for btree

Masahiko Sawada wrote:

> While hacking the btree code I found two points we can improve in nbtxlog.c.
> 
> @@ -135,7 +135,7 @@ _bt_clear_incomplete_split(XLogReaderState
> *record, uint8 block_id)
>                 Page            page = (Page) BufferGetPage(buf);
>                 BTPageOpaque pageop = (BTPageOpaque)
> PageGetSpecialPointer(page);
> 
> -               Assert((pageop->btpo_flags & BTP_INCOMPLETE_SPLIT) != 0);
> +        Assert(P_INCOMPLETE_SPLIT(pageop) != 0);
>                 pageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT;

Interesting.  We learned elsewhere that it's better to integrate the
"!= 0" test as part of the macro definition; so a
better formulation of this patch would be to change the
P_INCOMPLETE_SPLIT macro and omit the comparison in the Assert.  (See
commit 594e61a1de03 for an example).


> -               LockBuffer(hbuffer, BUFFER_LOCK_SHARE);
> +               LockBuffer(hbuffer, BT_READ);

I think BT_READ and BT_WRITE are useless, and I'd rather get rid of
them ...

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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