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
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