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Subject: Re: [RFC 02/11] perf/core: Data structure to present hazard data
To:     Mark Rutland <mark.rutland@arm.com>
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        yao.jin@linux.intel.com, robert.richter@amd.com,
        kim.phillips@amd.com, maddy@linux.ibm.com,
        Madhavan Srinivasan <maddy@linux.vnet.ibm.com>,
        Ravi Bangoria <ravi.bangoria@linux.ibm.com>
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From:   Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Date:   Tue, 3 Mar 2020 20:01:30 +0530
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On 3/2/20 8:24 PM, Mark Rutland wrote:
>> @@ -870,6 +871,13 @@ enum perf_event_type {
>>   	 *	{ u64			phys_addr;} && PERF_SAMPLE_PHYS_ADDR
>>   	 *	{ u64			size;
>>   	 *	  char			data[size]; } && PERF_SAMPLE_AUX
>> +	 *	{ u8			itype;
>> +	 *	  u8			icache;
>> +	 *	  u8			hazard_stage;
>> +	 *	  u8			hazard_reason;
>> +	 *	  u8			stall_stage;
>> +	 *	  u8			stall_reason;
>> +	 *	  u16			pad;} && PERF_SAMPLE_PIPELINE_HAZ
>>   	 * };
> 
> The existing comment shows the aux data *immediately* after ther
> phys_addr field, where you've placed struct perf_pipeline_haz_data.
> 
> If adding to struct perf_sample_data is fine, this needs to come before
> the aux data in this comment. If adding to struct perf_sample_data is
> not fine. struct perf_pipeline_haz_data cannot live there.
> 
> I suspect the latter is true, but you're getting away with it because
> you're not using both PERF_SAMPLE_AUX and PERF_SAMPLE_PIPELINE_HAZ
> simultaneously.

Right. Thanks for pointing it out. Will change it.

Ravi