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Subject: Re: [PATCH 05/11] perf intel-pt: Use itrace error flags to suppress
 some errors
From:   Adrian Hunter <adrian.hunter@intel.com>
To:     Andi Kleen <ak@linux.intel.com>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@redhat.com>, linux-kernel@vger.kernel.org
References: <20200709173628.5613-1-adrian.hunter@intel.com>
 <20200709173628.5613-6-adrian.hunter@intel.com>
 <20200709175046.GA1126680@tassilo.jf.intel.com>
 <3271e2cf-490b-5391-19e0-e1b019bfba1f@intel.com>
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Date:   Thu, 9 Jul 2020 21:22:16 +0300
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On 9/07/20 9:13 pm, Adrian Hunter wrote:
> On 9/07/20 8:50 pm, Andi Kleen wrote:
>> On Thu, Jul 09, 2020 at 08:36:22PM +0300, Adrian Hunter wrote:
>>> The itrace "e" option may be followed by a number which has the
>>> following effect for Intel PT:
>>> 	1	Suppress overflow events
>>> 	2	Suppress trace data lost events
>>> The values may be combined by bitwise OR'ing them.
>>>
>>> Suppressing those errors can be useful for testing and debugging
>>> because they are not due to decoding.
>>
>> I suspect it will be useful to more than just decoding and debugging.
>>
>> But the number is not a nice user interface.
>>
>> How about e[....] 
>>
>> like e[ol] 
> 
> Do you mean literally square-brackets? If you were really unlucky you might
> get pathname expansion with that.
> 
>>
>> Also it's a bit unusual that this disables instead of enables, but ok.

What about prefixing each flag with - i.e.

e-o
e-l
e-o-l