Re: [patch] perf_event_open.2: Exclude_host/exclude_guest clarification

["Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>]

Hello Joerg,

Ping!

Cheers,

Michael

On 02/17/2015 06:32 AM, Michael Kerrisk (man-pages) wrote:
> Hi Joerg,
> 
> Would you be willing to review/comment on Vince's patch, please.
> 
> Cheers,
> 
> Michael
> 
> On 02/11/2015 08:06 PM, Vince Weaver wrote:
>>
>> This patch relates to the exclude_host and exclude_guest bits added 
>> by the  following commit:
>>
>>    exclude_host, exclude_guest; Linux 3.2
>>         commit a240f76165e6255384d4bdb8139895fac7988799
>>         Author: Joerg Roedel <joerg.roedel@amd.com>
>>         Date:   Wed Oct 5 14:01:16 2011 +0200
>>
>>             perf, core: Introduce attrs to count in either host or guest mode
>>
>>             Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
>>             Signed-off-by: Gleb Natapov <gleb@redhat.com>
>>             Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
>>             Link: http://lkml.kernel.org/r/1317816084-18026-2-git-send-email-gleb@redhat.com
>>             Signed-off-by: Ingo Molnar <mingo@elte.hu>
>>
>> The updated manpage text clarifies that the "exclude_host" and
>> "exclude_guest" perf_event_open() attr bits only apply in the 
>> context of a KVM environment and are currently x86 only.
>>
>> This is a resend of the patch; the previous time I sent it
>> (http://thread.gmane.org/gmane.linux.man/7500) it did not
>> receive any comments.
>>
>> Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
>>
>> diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2
>> index 39c8d8c..1ea56c9 100644
>> --- a/man2/perf_event_open.2
>> +++ b/man2/perf_event_open.2
>> @@ -1006,11 +1006,25 @@ struct sample_id {
>>  .TP
>>  .IR "exclude_host" " (since Linux 3.2)"
>>  .\" commit a240f76165e6255384d4bdb8139895fac7988799
>> -Do not measure time spent in VM host.
>> +When conducting measurements that include processes running
>> +VM instances (i.e. have executed a
>> +.I KVM_RUN
>> +.BR ioctl (2)
>> +) only measure events happening inside a guest instance.
>> +This is only meaningful outside the guests; this setting does
>> +not change counts gathered inside of a guest.
>> +Currently this functionality is x86 only.
>>  .TP
>>  .IR "exclude_guest" " (since Linux 3.2)"
>>  .\" commit a240f76165e6255384d4bdb8139895fac7988799
>> -Do not measure time spent in VM guest.
>> +When conducting measurements that include processes running
>> +VM instances (i.e. have executed a
>> +.I KVM_RUN
>> +.BR ioctl (2)
>> +) do not measure events happening inside guest instances.
>> +This is only meaningful outside the guests; this setting does
>> +not change counts gathered inside of a guest.
>> +Currently this functionality is x86 only.
>>  .TP
>>  .IR "exclude_callchain_kernel" " (since Linux 3.7)"
>>  .\" commit d077526485d5c9b12fe85d0b2b3b7041e6bc5f91
>>
> 
> 


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/