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Subject: Re: [RFC][PATCH 4/5] tracing/filters: Provide basic regex support
From: Peter Zijlstra <peterz@infradead.org>
To: Tom Zanussi <tzanussi@gmail.com>
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Date: Fri, 07 Aug 2009 10:11:33 +0200
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On Thu, 2009-08-06 at 23:14 -0500, Tom Zanussi wrote:

> This a nice new feature - I considered doing it (not complete regexp
> support, just * in strings) for the original patch, but ran out of time
> - glad you added it.
> 
> I still think it makes sense to have some basic support for * in the
> regular filter file, so I'd vote for getting rid of the filter_regex
> file for now and just adding * support with the antislash escape to the
> regular filter file.  If you later wanted to add more full-fledged
> regexp support and it didn't make sense to do it in the regular filter
> file, then you could go crazy and add the filter_regex later...

I'll have to second this, /debug doesn't provide an ABI and having
multiple ways of expressing filters is just a pain.

I'm thinking of adding this filter capability to the perf tracepoints by
passing along a filter expression, having multiple ways of writing this
expression is just going to cause confusion.