[DTrace-devel] [PATCH v2] Do not use :: in IPv6 addresses without zero-collapsing

[Kris Van Hees]

On Tue, Sep 05, 2023 at 06:07:16PM -0400, Eugene Loh via DTrace-devel wrote:
> Reviewed-by: Eugene Loh <eugene.loh at oracle.com>
> 
> (I didn't get the patch post in my inbox.)
> 
> Anyhow, minor comments:
> 
> The text in the commit message:
>     Rather than adding a special
>     case in the output generation code for this, this patch adds a branch to
>     a code block that simply outputs 8 words, separated by ':'.
> is not needed since that mainly explains this implementation vis-a-vis a
> different implementation we are dropping.  The code itself is sufficiently
> clear.

Sure.

> There is a "zero-cord" that should be "zero-word."

Thanks.

> For the "full" loop, another option is to make the loop go 8 iterations. 
> Then back %r9 up by 1 before Ldone.  (There are arguments for and against
> that choice.)

Subtracting values from map_value pointers often leads to trouble in the BPF
verifier (especially on older kernels), so I try to avoid that as much as I
can.  It sometimes causes it to get confused.  I think that in this case, the
kernels we work with probably handle it correctly because it is using constant
values, but yes.  I could have gone either way, probably.

	Kris