Re: [Qemu-devel] [PATCH v3 01/11] util/qht: Document memory ordering assumptions

[Paolo Bonzini]

On 13/07/2016 01:19, Emilio G. Cota wrote:
> I wouldn't put those comments in the source--seqlock callers should
> know what they're doing, and what barriers seqlocks imply.

In general I'd agree with you, however in this case the "begin" calls
are what implements QHT's guarantee *for the caller*, so I think it's
worth having the comments.  In other words, if for any reason you do
anything before the read_begin and write_begin you still have to provide
barrier semantics.  It's not an explanation, it's a protection against
future mistakes.

There's no need for such comment at read_retry and write_end callsites,
though.

Also, it's spelled "guarantee". :)
Paolo


> I'm OK with stating what the implied ordering is in the header
> file, though.