Re: Remove useless pointer advance in StatsShmemInit()

Hi,

On Mon, Aug 18, 2025 at 06:13:05PM +0900, Michael Paquier wrote:
> On Mon, Aug 18, 2025 at 09:04:59AM +0000, Bertrand Drouvot wrote:
> > As StatsShmemInit() is existing code, let's fix it: the pointer is not used after
> > its last advance, so that advance is unnecessary and can be removed.
> > @@ -180,7 +180,6 @@ StatsShmemInit(void)
>
> * provides a small efficiency win.
> */
> ctl->raw_dsa_area = p;
> - p += MAXALIGN(pgstat_dsa_init_size());
> dsa = dsa_create_in_place(ctl->raw_dsa_area,
> pgstat_dsa_init_size(),
> LWTRANCHE_PGSTATS_DSA, NULL);
>
> One could argue that "p" could be removed, moving the
> sizeof(PgStat_ShmemControl) when we set raw_dsa_area, but that's a bit
> cleaner with the extra pointer assignment and the comment for
> pgStatLocal.shmem.

Yeah, that's probably just a matter of taste, but I also prefer keeping the
pointer over just doing:

ctl->raw_dsa_area = (char *) ctl + MAXALIGN(sizeof(PgStat_ShmemControl));

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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