From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christian Borntraeger <borntraeger@de.ibm.com>
Subject: trace points and ABI
Date: Wed, 06 Jun 2012 14:55:19 +0200
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Cc: Marcelo Tossati <mtosatti@redhat.com>,
	Jens Freimann <jfrei@linux.vnet.ibm.com>,
	Cornelia Huck <cornelia.huck@de.ibm.com>,
	Heinz Graalfs <graalfs@linux.vnet.ibm.com>,
	KVM <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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On 24/04/12 14:04, Avi Kivity wrote:
>> @@ -74,6 +74,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
>>  	{ "instruction_sigp_restart", VCPU_STAT(instruction_sigp_restart) },
>>  	{ "diagnose_10", VCPU_STAT(diagnose_10) },
>>  	{ "diagnose_44", VCPU_STAT(diagnose_44) },
>> +	{ "diagnose_9c", VCPU_STAT(diagnose_9c) },
>>  	{ NULL }
>>  };
>>  
> 
> We're switching to tracepoints instead of homebrewed statistics.  It's
> in feature-removal-schedule.txt already.  It's okay to add them now, but
> please prepare for their removal.
> 

Avi,

Do you consider these tracepoints itself ABI or not?

we are preparing some patches that add trace points in addition to
a: these stats
b: our debug feature

If this is not ABI, then we could work on these trace points step by step,
e.g. first use the existing stat/debug as trace point places, then combine,
add or remove  trace points later on if necessary.

Christian