Re: define pg_structiszero(addr, s, r)

Hi,

On Thu, Oct 31, 2024 at 09:59:35AM +0900, Michael Paquier wrote:
> On Thu, Oct 31, 2024 at 07:55:45AM +1100, Peter Smith wrote:
> > +/*
> > + * Test if a memory region starting at p and of size len is full of zeroes.
> > + */
> > +static inline bool
> > +pg_mem_is_all_zeros(const void *ptr, size_t len)
> >
> > The function comment should say 'ptr' instead of 'p', right?
>
> Yes.

Thank you both for looking at it. Agree, done in the new version attached.

> +static inline bool
> +pg_mem_is_all_zeros(const void *ptr, size_t len)
>
> While we're talking about wordsmithing things, I would not choose
> "mem" for this routine, just stick to "memory". There is not much in
> the code that does memory-specific things like what you are proposing
> here. Still, this would be more consistent with the macros for memory
> barriers at least. Hence, "pg_memory_is_all_zeros()" makes more
> sense?

That makes sense to me, done that way in the attached.

> The location of memutils.h is sensible.

Thanks for sharing your thoughts on it.

> + if (pg_mem_is_all_zeros(pagebytes , (BLCKSZ / sizeof(size_t))))
>
> Extra space not required after pagebytes.

Fat finger here, thanks!

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com