Re: [COMMITTERS] pgsql: Do all accesses to shared buffer headers through - Mailing list pgsql-hackers

Does any of this need to be backpatched?

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Tom Lane wrote:
> Log Message:
> -----------
> Do all accesses to shared buffer headers through volatile-qualified
> pointers, to ensure that compilers won't rearrange accesses to occur
> while we're not holding the buffer header spinlock.  It's probably
> not necessary to mark volatile in every single place in bufmgr.c,
> but better safe than sorry.  Per trouble report from Kevin Grittner.
> 
> Modified Files:
> --------------
>     pgsql/contrib/pg_buffercache:
>         pg_buffercache_pages.c (r1.4 -> r1.5)
>
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/pg_buffercache/pg_buffercache_pages.c.diff?r1=1.4&r2=1.5)
>     pgsql/src/backend/storage/buffer:
>         bufmgr.c (r1.195 -> r1.196)
>
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/buffer/bufmgr.c.diff?r1=1.195&r2=1.196)
>         freelist.c (r1.52 -> r1.53)
>
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/buffer/freelist.c.diff?r1=1.52&r2=1.53)
>     pgsql/src/include/storage:
>         buf_internals.h (r1.79 -> r1.80)
>         (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/storage/buf_internals.h.diff?r1=1.79&r2=1.80)
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 9: In versions below 8.0, the planner will ignore your desire to
>        choose an index scan if your joining column's datatypes do not
>        match
> 

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