[PATCH] arm: armv7: perf: fix armv7 ref-cycles error

gregkh at linuxfoundation.org gregkh at linuxfoundation.org
Wed Oct 8 06:31:47 PDT 2014


On Wed, Oct 08, 2014 at 10:17:41AM +0100, Will Deacon wrote:
> On Wed, Oct 08, 2014 at 04:06:12AM +0100, zhangzhiqiang wrote:
> > hi all,
> > ----------------------------------------
> > 
> > ref-cycles event is specially to Intel core, but can still used in arm architecture
> > with the wrong return value with 3.10 stable. for instance:
> > 
> >  perf stat -e ref-cycles sleep 1
> > 
> >  Performance counter stats for 'sleep 1':
> > 
> >   	0 ref-cycles
> > 
> >        1.002381916 seconds time elapsed
> > 
> > this patch fix the bug and make it return NOT SUPPORTED
> > distinctly.
> > 
> > In upstream this bug has been fixed by other way(not primary for the bug), which changes more than one file
> > and more than 1000 lines. the primary commit is 6b7658ec8a100b608e59e3cde353434db51f5be0.
> > besides we can not simply cherry-pick.
> 
> I thought I saw Greg pick this up the other day?

Yes, it's in 3.16.4, did I do something wrong by accepting it?

confused,

greg k-h



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