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Date:   Wed, 26 Apr 2023 23:12:15 +0900
From:   Masami Hiramatsu (Google) <mhiramat@kernel.org>
To:     Alan Maguire <alan.maguire@oracle.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        "Masami Hiramatsu (Google)" <mhiramat@kernel.org>, corbet@lwn.net,
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        linux-kselftest@vger.kernel.org
Subject: Re: [PATCH tracing 0/3] tracing: support > 8 byte filter predicates
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On Wed, 26 Apr 2023 09:51:00 +0100
Alan Maguire <alan.maguire@oracle.com> wrote:

> On 25/04/2023 18:20, Steven Rostedt wrote:
> > On Tue, 25 Apr 2023 18:15:03 +0100
> > Alan Maguire <alan.maguire@oracle.com> wrote:
> > 
> >> that's a great idea; what would be the most consistent ftrace syntax
> >> for this do you think? I noticed that hist triggers append a modifier
> >> to the field name so would something like
> >>
> >> "dst.ipv6 == ::1"
> > 
> > Yeah, I think just having ":" in the name without quotes can help the filter
> > know that it's a ipv6 id.
> > 
> > Hmm, although we may want to do the same for mac addresses. But we can
> > determine the difference by the field size. If it's 6 bytes, it's a mac, if
> > it's 128 bits, then ipv6.
> >
> 
> good idea! so what about the following
> 
> - 16 byte field with ':'; convert from IPv6 address before memcmp()ing
> - 6 byte field with ':'; convert from MAC address before memcmp()ing
> - 4 byte field with '.'; convert from IPv4 address before memcmp()ing
> - 0x prefix, any other size; basic memcmp

This looks good to me :)

Thanks!

> 
> ? Thanks!
> 
> Alan
>  
> > -- Steve
> > 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>